Saturday, November 30, 2019

Engineering Process Productivity Improvement - Process Charts - Industrial Engineering Analysis



Frank Gilbreth proposed the method of process charts to study and improve processes.

In the subsequent days, two process charts became important.

1. Operation Process Chart for study and improvement of material transformation operations and inspections.

2. Flow Process Chart that studies flow of the materials, components and finished item across operations, inspections, temporary delay points and permanent storage places. Transportation and stacking the material between work benches, inspection benches and storage/delay places, and even material handling to load and unload work pieces, work holding equipment, and tools are also transport and handling operations. Flow process chart can depict all types of flow, delay (store), and handling material.

Flow process chart shows five types of activities.

Operation
Inspection
Transportation
Temporary Delay
Permanent Storage.

Each of these activities can be analyzed using industrial engineering methods and studies.

More activities can be added to process charts to include more items needing analysis. Energy and information are two such items which are to be added to process charts.


Shigeo Shingo explained very well how Toyota Production System emerged from the process improvement based on flow process chart. He strongly stated the fact that Toyota Production System is the excellent output from industrial engineering promoted by Japan Management Association for many years.

Read Shigeo Shingo's explanation

Toyota Production System Industrial Engineering (TPS IE) Part 1


In each activity there are machine activities and manual activities.  Machine activities can be studied under machine work study (process industrial engineering) and manual activities using human effort industrial engineering (human work study).


Machine Work Study - Study Areas

Aspects of Machine to be Studied


Advanced Machine Availability
Replacement
Condition of the Machine (Repair & Overhaul Need)
Improvement of the Machine
Accessories
Cutting Tools
Machine Speeds
Setup Procedure
Upkeep of the machine by operator
Power consumption
Breakdowns analysis
Data Generation and Analysis

https://nraoiekc.blogspot.com/2019/11/machine-work-study-study-areas-2018.html



Industrial Engineering Analysis of Main Transformation Operation


The tools  and equipment used to perform the operation needs to analysed logically. The following questions are the sort that will lead to suggested improvements:

1. Is the machine tool best suited to the performance of the operation of all tools available?

2. Would the purchase of a better machine be justified?

3. Can the work be held in the machine by other means to better advantage?

4. Should a vise be used?

5. Should a jig be used?

6. Should clamps be used?

7. Is the jig design good from a motion-economy standpoint?

8. Can the part be inserted and removed quickly from the jig?

9. Would quick-acting cam-actuated tightening mechanisms be desirable on vise, jig, or clamps?

10. Can ejectors for automatically removing part when vise or jig is opened be installed?

11. Is chuck of best type for the purpose?

12. Would special jaws be better?

13. Should a multiple fixture be provided?

14. Should duplicate holding means be provided so that one may be loaded while machine is making a cut on a part held in the other?

15. Are the cutters proper?

16. Should high-seed steel or cemented carbide be used?

17. Are tools properly ground?

18. Is the necessary accuracy readily obtainable with tool and fixture equipment available?

10. Are hand tools pre-positioned ?

20. Are hand tools best suited to purpose?

21. Will ratchet, spiral, or power-driven tools save time?

22. Are all operators provided with the same tools?

23. Can a special tool be made to improve the operation?

24. If accurate work is necessary, are proper gages or other measuring instruments provided?

25. Are gages or other measuring instruments checked for accuracy from time to time?


Processing Operations Improvement - Illustrations - Shigeo Shingo's Book on IE Study of TPS 

Examples in the book

Manufacturing operations can be improved by alternatives related to proper melting or forging temperatures, cutting speeds or tool selection.

Examples related to vacuum molding, plating and plastic resin drying are given in the book.

Eliminating Flashing in Castings (Die)
Flashing in die castings occurs due to escape of air.
Removing the air in mould with a vacuum pump eliminated flashing.

Removing Foam in High-Speed Plating
Spraying or showering the surface to be painted resulted in a 75% reduction.


Drying Plastic Resin
Letting the resin dry a little at a time by allowing it to float to the surface resulted in a 75% reduction of electric power consumption.


Engineering/Technology Knowledge

Gideon Halevi, Process and Operation Planning, Kluwer Academic Publishers


Industrial Engineering Analysis of Inspections

Analysis of Inspection Operations

Shingo said normal inspection is judgment inspection.
It separates good and defective items.
Rework done on defective items if possible
Informative inspection asks for process improvement.
It is like medical examination that leads to treatment.


Statistical Process Control
SPC is sampling based informative inspection. But Shingo says even it is not sufficient to assure zero defects.

To assure zero defects we need to inspect every item but at low cost per item.

Shingo’s Suggestions
Informative Inspections

Self Inspection
Successive Inspection
Enhanced Self Inspection – Inspection enhanced with devices  - poka-yoke

Example  – Vacuum Cleaner Packing
Cleaner along with attachments and leaflets to be packed.
When a leaflet is taken from the pile,  a limit switch is operated.
When attachments are taken from the container, a limit switch is operated.
Then only, the full package is allowed to be sealed.
Principle
The purpose of inspection is prevention of the defect.
Quality can be assured when it is built in at the process and when inspection provides immediate and accurate feedback at the source to prevent the defective item to go further.
Self Inspection
It provides the most immediate feedback to the operator.
He can improve the process and also rework on the item.
Disadvantage inherent.
There is potential for lack of objectivity.
He may accept items that ought to be rejected.
Successive Inspection
The operator inspects the item for any defect in the previous operation before processing it.
Shingo says, when this was introduced defects dropped to 0.016% in Moriguchi Electric Company in television production
Inspection enhanced by Poka Yoke
Human operation and inspection can still make errors unintentionally.
Poka Yoke will take care of such errors.
Ex: Left and right covers are to be made from similar components with a hole in different places.
The press was fitted with a poka yoke which does right cover pressing only when the hole is in proper place.
Source Inspection
This is answering the question: What is the source of the defect in the process/operation?
Two types proposed.
Vertical
Horizontal
Source Inspection – Vertical, Horizontal
Vertical source inspection traces problems back through the process flow to identify and control conditions external to the operation that affect quality.
Horizontal source inspection identifies and controls conditions within an operation that affect quality.
Poka-yoke Inspection Methods
Poka-yoke achieves 100% inspection through mechanical or physical control.
Poka-yoke can either be used as a control or a warning.
As a control it stops the process so the problem can be corrected.
As a warning, a buzzer or flashing lamp alerts the worker to a problem that is occurring.


Industrial Engineering Analysis of Transportation


Analysis of Transport Operations

Transport within the plant is a cost that does not add value.
Hence real improvement of the process eliminates the transport function as much as possible.
This involves improving the layout of process.

Ex – 7. Transport Improvement
Tokai Iron Works – process layout -  presses, bending machines, embossing
Layout Change: Flow based layout.
A 60 cm wide belt conveyor with ten presses on either side.
WIP reduced. Production time shortened. Delays disappeared.
200% increase in productivity.
Principle
Only after opportunities for layout improvement have been exhausted should the unavoidable transport work that remains be improved through mechanization.




Industrial Engineering Analysis of Delays 


Eliminating - Storage Operations (Delay)


Process Delay – Permanent storage – Whole lot is waiting
Lot Delays – Temporary storage – One item is being processed. Other items in the lot waiting.
Another classification is storage on the factory floor and storage in a controlled store.
Eliminating - Storage Operations (Delay)
There are three types of accumulations between processes:

E storage - resulting from unbalanced flow between processes  (engineering)
C storage - buffer or cushion stock to avoid delay in subsequent processes due to machine breakdowns or rejects (control)
S storage - safety stock; overproduction beyond what is required for current control purposes

Eliminating E-Storage

E-storage is due to engineering/planning/design of the production-distribution  system
This can be eliminated through leveling quantities, which refers to balancing flow between high and low capacity processes and synchronization.

Leveling would mean running high-capacity machines at less than 100% capacity, in order to match flow with lower capacity machines that are already running at 100% on short interval basis.
At Toyota, the quantity to be produced is determined solely by order requirements (Takt time).

Principle
Presence of high capacity machines should not be used to justify large lot processing and resulting inventory.
Process capacity should serve customer requirements/production requirements and should not determine them
synchronization.
The lots especially one piece lot is processed without delay in a flow.
It is efficient production scheduling that ensures that once quantities are leveled (output is matched), inventories do not pile at any stage due to scheduling conflicts.
Synchronize the entire process flow.


Eliminating C storage - Cushion

Cushion stocks compensate for:
machine breakdowns,
defective products,
downtime for tool and die changes and
sudden changes in production scheduling.

Eliminate Cushion Storage
Prevent machine breakdowns:
Determining the cause of machine failure at the time it occurs, even if it means shutting down the line temporarily.
Total Productive Maintenance movement.

Eliminate Cushion Storage
Zero Defect Movement.
Total quality management.
Use better inspection processes:
Self Inspection.
Successive Inspection.
Enhancement to inspection through Poka Yoke
Eliminate Cushion Storage
Eliminate Lengthy setups and tool changes
Implement SMED to eliminate long set-up times and tool changes
Running smaller batch sizes to allow for quick changes in production plans

Eliminate Cushion Storage
Absorb Change in Production Plan
Running smaller batch sizes allows for quick changes in production plans without disturbing flow production to significant extent.

Eliminating Safety (S) storage

Safety stock is kept not to take care of any predicted problem but to provide additional security
It may guard against delivery delays, scheduling errors, indefinite production schedules, etc.
Ex. 10 Delivery to stores
In example 2.10 Shingo mentions a company wherein vendors supply to store and from store components are supplied to assembly line.
Shingo suggested that vendors should directly supply the day’s requirements to assembly floor and in case of any problem, components in the store can be used.
Less Need for Safety Stock Observed
That practice led to the observation that very less safety stock is needed in the store.

Shingo recommends keeping a small controlled stock that is only used when the daily or hourly scheduled delivery fails or falls behind.
In case of unexpected defects also it can be used.


The safety stock can then be replenished when the scheduled materials arrive, but the supply of materials due for the process go directly to the line, rather than normally going into storage first.
This is the essence of the just-in-time supply method.


Eliminating lot delays
While lots are processed, the entire lot, except for the one piece being processed, is in storage (is idle).
The greatest reduction in production time can be achieved when transport lot sizes are reduced to just one; the piece that was just worked on.

SMED
Using SMED (single-minute exchange of dies), set up time is decreased so large lot sizes are no longer necessary to achieve machine operating efficiencies.
SMED facilitates one item lot sizes.


Layout Improvement - Flow
Transportation changes can be accomplished through flow  layout and using gravity feed Chutes which result in shorter production cycles and decreases in transport man-hours.

Reducing Cycle Time
Generally, semi-processed parts are held between processes 80% of the time in a production cycle time.
It quantity leveling is used and synchronization of flow is created, the cycle time can be reduced by 80%.
By shifting to small lot sizes will further reduce cycle time.


TPS – Reduction of Delays or Storage
Methods of reducing production time delays (JIT) is the foundation of Toyota Production System.
It clearly brings down production cycle time and thereby offers small order to delivery time.



Industrial Engineering Analysis of Storage


Storage/Warehouse Improvement

Conventional warehouses: Simple, yet effective
As the industry continues unprecedented transformation, some of the classic approaches still hold up.
Josh Bond, Senior Editor · October 14, 2019
https://www.logisticsmgmt.com/article/conventional_warehouses_simple_yet_effective

Improving Your Manufacturing Operations Using Warehouse Automation 
June 27, 2019
Blog post written by John Hinchey, VP of Sales for Westfalia Technologies, Inc., a leading provider of logistics solutions for plants, warehouses and distribution centers.
https://scm.ncsu.edu/scm-articles/article/improving-your-manufacturing-operations-using-warehouse-automation

Proposing a new framework for lean warehousing: first experimental validations
Conference Paper,   2017

Lean warehousing plays a significant role in order to achieve lower costs of logistics operations and increase flexibility and efficiency in  supply chains.  . This paper proposes a novel lean warehousing framework combining three well-known lean tools and presents the first outcomes of its validation campaign. It discusses the framework application to a raw material and component warehouse of an international company in the automotive sector. Results show that time savings up to 36% might be achieved in receiving, put away, and picking operations, bringing significant economic benefits in terms of labour, service level, and warehouse space.
https://www.researchgate.net/publication/329588949_Proposing_a_new_framework_for_lean_warehousing_first_experimental_validations













Friday, November 29, 2019

SMT Machine - Production Line - Machine Work Study - Machine Productivity Improvement



Increasing efficiency of SMT

SMT is a system engineering project that involves components and their packaging and tape form, PCB, materials and accessories, design, manufacturing technology and production process, equipment and spare parts, tooling, inspection and management. Production technology, only focusing on a certain link or a certain number of links, can not achieve a good sense of good operation. In the past, some enterprises have a misunderstanding of understanding, and it is considered that the placement equipment is used well and SMT is running well. The actual situation is not so simple, all the links that make up SMT are interrelated.

The design process is not a traditional design idea. It requires technical decision makers and designers to understand and use SMT from a deep level, familiar with equipment and processes, and use and promote SMT on new products and technologies.

http://www.wisdommobi.com/wdgweb_content-63800.html
Included first in Process Planning - Bibliography
https://manufacturing-videos.blogspot.com/2019/08/process-planning-bibliography.html


SMT (surface mount technology) component placement systems, commonly called pick-and-place machines or P&Ps, are robotic machines which are used to place surface-mount devices (SMDs) onto a printed circuit board (PCB). They are used for high speed, high precision placing of broad range of electronic components, like capacitors, resistors, integrated circuits onto the PCBs which are in turn used in computers, consumer electronics as well as industrial, medical, automotive, military and telecommunications equipment.
https://en.wikipedia.org/wiki/Pick-and-place_machine


How does SMT electronics assembly work?
01.08.2014

Electronics manufacturing using surface-mount technology (SMT) simply means that electronic components are assembled with automated machines that place components on the surface of a board (printed circuit board, PCB).
https://www.eso-electronic.com/en/knowledge-base/manufacturing/how-does-smt-electronics-assembly-work/


(SMT) Line Productivity Improvement


Intelligent IoT Connected SMT System
Intelligent Factory
IoT/M2M Integration system - System allows linking our SMT machines to equipment made by other companies and give all-around high productivity in the mounting process.
https://global.yamaha-motor.com/business/smt/software/ifactory/


High Speed YAMAHA SMT Production Line
YAMAHA SMT Assembly line
YAMAHA PCB Assembly line
YAMAHA SMT production line
YAMAHA PCB production line
Product description: High Speed YAMAHA SMT Production Line, with 2 High speed Yamaha Z LEX YSM20R and 1 multifunciton Yamaha YSM10,
Mounting speed can reach 200000 CPH. Really fast for Mobile phone, LED light production,
https://www.flason-smt.com/product/High-Speed-YAMAHA-SMT-Production-Line.html


Smart SMT Lines
Production – Maximum performance, maximum quality
Let your SMT lines run non-stop and gain a competitive advantage through maximum productivity and quality.
https://www.asm-smt.com/en/products/workflows/production/

Improving printed circuit board surface mount technology (SMT) line productivity with preventative maintenance and cause and effect analysis
By Lee Whiteman
https://www.ventureoutsource.com/contract-manufacturing/printed-circuit-board-surface-mount-technology-SMT-line-productivity-preventative-maintenance-cause-effect-analysis


Line Efficiency and Assembly Environment Benchmarking Study,CEERIS Report

The number of components assembled per pick-and-place machine per staffed hour averages 2,340 for the entire sample. It reaches 2,480 at OEMs and is 2,300 at CMs.
http://smt.iconnect007.com/index.php/article/52474/--line-efficiency-and-productivity-measures/52477/?skin=smt

SMT LINE OPTIMISATION
Our team will assist you to achieve the highest level of productivity, achieving the best CPH, UPH, and yield through our proposed solutions.
2019
https://trans-tec.com/support/smt-line-optimisation/

LINE BALANCING AND PRODUCTIVITY IMPROVEMENTS IN ELECTRONICS ASSEMBLY USING MODELING AND SIMULATION TECHNIQUES
Author: S. Manian Ramkumar
Company: Rochester Institute of Tech.
Date Published: 2/5/2002   Conference: Pan Pacific Symposium
https://www.smta.org/knowledge/proceedings_abstract.cfm?PROC_ID=935

Create an Optimized SMT Production Plan




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4 March 2017

How to make a PCB prototyping with UV soldermask - STEP by STEP
1,668,835 views•19 Nov 2016
wegstr.com
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Making PCB with 3D printer and permanent marker
820,335 views•29 Mar 2015
Lamja Electronics
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FreePCB is used to create PCB layout and a gerber-file. Flatcam is used to generate g-code for  K8200 3D-printer. A sharp metal rod is then used for removing the ink from the copper clad, and then it was etched with ferric chloride.

Comments:
I think using photoresist film is better, cheap and efficient than this

i think using a laser printer is pretty easy honestly.
Laser cutter? Maybe not on Cu.

you will be faster if u use a PCB with foto active skinn and then make a print with UV light. Tought u use it to remove all copper, what would make sense, about then is no chemical need.

can u mod it to be a cnc machine? it sounds nicer.

why not just print stencil with marker, instead of scratching it with rod?

G code needs improvement. g code generator is not working right.  No reason that needs to do so many z retracts for this.  Too much time up & down, not enough time contact & move.

It is taking more time than other pcb milling machines. The first trace is made 5-6 rounds around that to make it right.

Why not let the printer draw the circuits with a Marker modification? you save much more ink and its cheaper? thanks

 this would not function as an actual PCB. If I am missing something please let me know.

Don't bother etching with ferric in a bath..just take a sponge and rubber gloves..apply straight onto the board and rub for 1 minute...use denatured alcohol to remove ink. I got a stepcraft cnc and will use that to drill out the holes AND plot the design.

For small PCBs, its not worth the time to design and build a PCB, when I can wire it up and solder it in less than an hour.



SMT Process Description

17 Steps
http://www.news.newburyelectronics.co.uk/newbury-blog/guide-to-pcba-process/


https://www.eso-electronic.com/en/knowledge-base/manufacturing/how-does-smt-electronics-assembly-work/

https://www.seeedstudio.com/blog/2019/07/10/9-must-know-pcb-assembly-pcba-equipment/  - Machines



2016
http://stiusa.com/news/sti-acquires-new-high-speed-flexible-mounter/
mounts 20,900 chips per hour.







Industrial Engineering and Lean Manufacturing Concept


The persons in leadership roles in industrial engineering discipline have failed industrial engineering discipline.  Peter Drucker, the management guru highlighted the issue. They have not augmented industrial engineering discipline adequately and ceded ground to other professional associations mainly because they pursued short term incomes following the latest successful fad without developing the IE discipline through appropriate research and method development and improvement efforts.

IE is very broad in its foundation purpose to contribute to any technology developed in any engineering branch. Similary is it has the mandate to respond to any development in management or in any social science. Developments in other subjects strengthen IE. They do not weaken its purpose or practice.

Lean Has Failed!
Jim Womack in  Planet Lean


On the occasion of  the 20th anniversary of the founding of the Lean Enterprise Institute and the 10th anniversary of the Lean Global Network  – Womack said that he was thinking about the original promise of the lean movement  created by the books "The Machine That Changed the World in 1990" and "Lean Thinking in 1996.“

Failures of lean is an idea in that thinking.

The article by Michel Baudin discusses the issue further.
https://michelbaudin.com/2017/09/03/where-lean-has-failed-jim-womack-planet-lean/


I made a comment on it. I have taken important points from others comments and replies. You can read full comments from the above Baudin's post.

Narayana Rao KVSS
SEPTEMBER 11, 2017 @ 10:00 PM
Comment on LinkedIn:

I attended the 2017 Annual Conference of IISE and presented Principles of Industrial Engineering. Lean systems as systems having 50% or 100% productivity advantage was a correct description for what TPS achieved in comparison to other earlier productive organizations. It is a wrong strategy to ignore the earlier productivity improvement discipline “industrial engineering’ altogether. The lean movement would have succeeded to a more extent if industrial engineers were included in the strategic thrust right from the start. Yes, still what Womack says is right. The lean transformation of systems giving a significant boost to productivity has to be continued by finding root causes for the delay in transformation projects and lower than expected results.

A reply by  Ashok Motwani


Where is an evidence that industrial engineering was ignored when Lean ‘movement’ was started and was part of some strategy?

My reply Narayana Rao KVSS
SEPTEMBER 11, 2017 @ 10:11 PM


Yes. The books on lean by Womack actually criticized IE. They did not interpret lean as an advance in IE or productivity movement. They did not recommend adding lean section in IE. They recommended a separate lean promotion office without any reference to IE department. In the Pittsburgh conference, I actually heard from professional IEs, that they were ignored by the lean movement.

Michel Baudin replied

There are many types of engineering involved with manufacturing, but essentially ignored by the bulk of the “Lean movement.” Under the Lean flag,  people like Art Smalley or JT Black and myself. did not ignore them.

Process engineers work on the physics and chemistry of the manufacturing process in laboratories; manufacturing engineers on process planning in the factory or shop floor. industrial engineers  work on the shop floor to improve the process on a continuous basis to reduce costs further.

Social scientists downplay the engineering dimension of TPS because they don’t understand it.

Lonnie Wilson then commented

I am amazed that Womack and other academics who studied rather than implemented Lean have become such thought leaders. "I would add that the key is to understand it. That understanding comes from actually doing it….and doing it as a manager within a company, rather than doing is as a consultant at arms length…"

REPLY
Michel Baudin
Good managers don’t always make good consultants and vice versa. The two are different professions, best suited for different personalities and require different skill sets.

In manufacturing, before becoming consultants, I think people should first put in 5 to 10 years as engineers or managers in a manufacturing company after coming out of school. If they are comfortable in that environment and adept at managing their careers in it, they are better off staying and rising through the ranks.




Machine Cost and Work Measurement - Time and Cost Estimates for Metal Forming Processes





Estimation of Forging Cost and Time



Material Estimation for the Forging

Expected Losses in Forging


The losses expected in forging are:

(i) Scale loss.
(ii) Flash loss.
(iii) Tonghold loss.
(iv) Sprue loss.
(v) Shear loss.


(i) Scale loss

When the material used in forging, iron is heated at a high temperature in atmospheric conditions a thin film of iron oxide is formed all round the surface of the heated metal.  The iron oxide film falls from the surface of the metal on being beaten up by the hammer. This is termed scale loss and it depends upon the surface area, heating time and the type of material. For forgings under 5 kg, the loss is 7.5 per cent of the net weight, and for forgings from 5 to 12.5 kg and over an addition of 6 per cent and 5 per cent of the net weight is expected as the scale loss.

(ii) Flash loss

This is a loss related to die forging or machine forging.

There is a certain quantity of metal which comes between the flat surfaces of the two dies after
the die cavity has been filled in. This material equal to the area of the flat surface is a wastage. For
finding the flash loss, the circumference is determined which multiplied by cross-sectional area of
flash will give the volume of the flash. The volume multiplied by material density gives the flash loss. Generally, it is taken as 3 mm thick and 2 mm wide all round the circumference.


(iii) Tonghold loss

This is the loss of material due to a projection at one end of the forging to be used for holding it
with a pair of tongs and turning it round and round to give the required cross section in drop forging.
About 1.25 cm and 2.5 cm of the size of the bar is used for tonghold. The tonghold loss is equal to
the volume of the protections. For example, the tonghold volume loss for a bar of 2 cm diameter and tonghold length 2 cm will be  (π/4)*2(cube) =   1.25 cm(cube)


(iv) Sprue loss

The connection between the forging and tonghold is called the sprue or runner. The material loss
due to this portion of the metal used as a contact is called sprue loss. The sprue must be heavy
enough to permit lifting the workpiece out of the impression die without bending. The sprue loss is
generally 7.5 per cent of the net weight.



(v) Shear loss

In forging, the long bars or billets are cut into required length by means of a sawing machine.
The material consumed in the form of saw-dust or pieces of smaller dimensions left as defective
pieces is called shear loss. This is usually taken as 5% of the net weight.


Thus nearly 15 to 20% of the net weight of metal is lost during forging. The expected loss of material has to  be added to the net weight to get the gross weight of the material.


Forging Cost


The cost of a forged component consists of following elements:
(i) Cost of direct materials.
(ii) Cost of direct labour.
(iii) Direct expenses such as due to cost of die and cost of press.
(iv) Overheads.


(I) Direct material cost

Cost of direct materials used in the manufacture of a forged component are calculated by first determing the net weight based on component drawing and then adding expected losses.


(i) The net weight of forging

Net weight of the forged component is calculated from the drawings by first calculating the
volume and then multiplying it by the density of the metal used.
Net weight = Volume of forging × Density of metal.


(ii) Gross weight
Gross weight is the weight of forging stone required to make the forged component. Gross
weight is calculated by adding expected losses.

Gross weight = Net weight + Material loss in the process.

In case of smith or hand forging, only scale loss and shear loss are to be added to net weight but
in case of die forging other machine related losses are also to be taken into account. 

(iii) Diameter and length of stock
The greatest section of forging gives the diameter of stock to be used and
Length of stock = (Gross weight)/[ Sectional area of stock× Density of material]

(iv) The cost of direct metal is calculated by multiplying the gross weight by price of
the raw material
Direct material cost = Gross weight × Price/kg.


(II) Direct labour cost

Direct labour cost = t × l
Where t = Time for forging per piece (in hrs)
l = Labour rate per hour

No general formula is given in books for forging. It has to be estimated internally using time study data of the past.


(III) Direct expenses
Direct expenses include the expenditure incurred on dies and other equipment, cost of using
machines and any other items, which can be directly identified with a particular product.

The method
of apportioning die cost and machine cost:


Apportioning of die cost Let cost of die = Rs. x
No. of components than can be produced using this die be  y components
Cost of die/component = Rs. x/y

Apportioning of machine (press) cost

Let cost of press = Rs. A
 Life of press be n years

 Life of press in hours = B =  n × 12 × 4 × 5 × 8 = 1920 n hours
(Assuming  12 months in a year, 4 weeks in a month, 5 days a week, 8 hours of working per day, 
Hourly machine price cost of production = A/B
No. of components produced per hour = N
Cost of using press per component = A/ (BN) Rs.

This excludes cost of power consumed and other consumables.


(IV) Overheads expenses

The overheads include supervisory charges, depreciation of plant and machinery, consumables,
power and lighting charges, office expenses etc. The overheads can be  expressed as percentage
of direct labour cost or machine hours.

The total cost of forging is calculated by adding the direct material cost, direct labour cost, direct
expenses and overhead.

Three hundred pieces of the bolt are to be made from 25 mm diameter rod. The head has to be 40 mm dia.  The length of the head is 22mm and the length of the remaining bolt is 113 mm. Find the
length of material required for forging by upsetting. What length of the rod is required if 4% of the length goes as scrap?


Volume of head of the bolt = (π/4)* D(square)* L

D = 40 mm
L = 22 mm
=  (π/4)* 40(square)*22  =   27,646 mm(cube)

Length of material required for making the head
= Volume/area of the blank  being used
In the problem the dia. of the blank used is 25 mm

Area =  (π/4)* 25(square)  =  490.6 mm

∴ Length of bar = 27,632/490.6 =  56.35 mm

Total length required for forming = 56.35 + 113 = 169.35 mm
Length of rod required for making 300 bolts = 169.35*300/1000     =   50.8 metre

Considering loss 4%,
Total length required = (50.8 + .4) × 50.8 = 71.12 metre

Thursday, November 28, 2019

80 - 20 Rule in Industrial Engineering - 80% Engineering - 20% Human Motions and Movements



"Industrial Engineering is System Efficiency Engineering and Human Effort Engineering."  - Narayana Rao.



Actually system efficiency engineering is sufficient description for industrial engineering scope and activity. But human effort engineering is added to highlight the fact that all among all engineering branches industrial engineering has the maximum focus on human effort in engineering systems. The role of man in machine system is studied in detail and engineering of the effort is done so that it is effective as per the requirement of the machine operation and efficient and comfortable to the operator;. 


Industrial engineering is 80% Engineering - 20% Human Motions and Movements




Industrial engineering is 80% Engineering


Industrial engineering adds value in  organizations through engineering changes that it identifies, develops, and installs in engineering systems in products, components, materials, machines, methods (machine operation steps specifications), energy related aspects and information system.

We can say industrial engineering is done on Inputs - Process - Output.


Industrial engineering is intensive engineering.


Engineering changes identified by industrial engineers demand use of engineering intensively and creatively to develop the engineering solution and implement it. It is in areas of complete product design, component design, material specification, machine specification, machine accessories and tooling specification, machine work holding specification, machine operation specification, mechanical handling of the material, maintaining atmospheric conditions in the shop and work cells, energy input and utilization, information generation, processing, storage, communication and action etc.

The study of human motions and movements and the time taken to make those motions does occupy only around 20% or less of industrial engineers' effort. 80% of the activities are in the area of engineering.

Effective and successful Industrial engineering practice requires engineers of highest calibre as in the role of industrial engineering they have to use full engineering knowledge to locate engineering change opportunities that will enhance productivity in any element of the engineering system. In comparison, core engineers can specialize in design of specific machine components and work on the topic for many years in their service. Not so in industrial engineering. From day one, industrial engineer has to remember much bigger set of engineering knowledge, keep abreast of technical developments and make effort to absorb them into the technology as fast as possible. 

Industrial engineering is continuous engineering of products and processes.


Industrial engineers work on the shop floor along with operating engineers and do engineering changes on a continuous basis and improve the products and processes  so that they are more productive and less costly and thus make sure that market grows for the product on a continuous basis. They do take care of many complaints of operators regarding process difficulties and make sure that process improvement is continuous.


We can say: What is IE?


Industrial engineering is Gemba based (現場)  continuous engineering of products and processes to increase productivity/efficiency/cost reduction.


Industrial Engineering - Principles and Practice

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Wednesday, November 27, 2019

Industrial Engineering Accompanied by Cost Estimating




Industrial Engineering is System Efficiency Engineering. - Narayana Rao


It makes engineering changes to products and processes to increase their efficiency - increase their productivity which means reduction in costs.

In some defence related engineering/production organizations, industrial engineering department is given the responsibility of preparing cost estimates to support marketing activity also apart from preparing cost budgets for production departments and processes. It is a rational way of organizing and industrial engineering discipline has the required activities in place in theory to support cost estimation for marketing purposes. So, we can say industrial engineering departments have the necessary data and activities in place to support marketing related cost estimation and also production budget related cost estimation.

In this connection the following modified explanation of industrial engineering given in the web site https://www.myaccountingcourse.com/accounting-dictionary/industrial-engineering-method is worth knowing.

What is the Industrial Engineering Method?

Definition: Industrial engineering method is a physical way of examining the relationship between cost drivers and costs by analyzing the inputs coming into the company, the outputs that are created, and the work that goes into the process. In other words, it is a detailed look at the entire production process and how that process affects the costs of an organization.

What Does Industrial Engineering Method Mean?
What is the definition of industrial engineering method? Regardless of the specifics of a manufacturing process, units go in and outputs are created at a manufacturing company. When there is a physical relation between those inputs and outputs, analyzing that relationship can help managers to examine and control costs. Industrial engineering measurements related to productivity and cost help in this. Time taken by machines and men is directly related to productivity of resources and cost of output. Therefore time studies that measure  how much direct machinery time and manpower time  is needed to produce a certain amount of output are conducted by industrial engineers. Time study is also the basic measurement for efficiency improvement. Reducing the machine hours and labour hours based on engineering modifications is the focus of industrial engineering. Hence every industrial engineering project or study begins with a time study, cost study, and productivity study. When an industrial engineering project is completed, its benefits are indicated by once doing a time study, cost study and productivity study. As an intermediate stage, estimates of time, cost and productivity are made by industrial engineers.

The site gives the example of a large business that manufactures curtains with some being cloth, dye, thread, machine hours, and labor, and output being  the finished curtain. Industrial engineering identifies the  physical relationships between the inputs and the output. It will measure or determine  how much of each input produces a certain amount of output (partial productivity of the input). For example, the finding that  it takes two hours of direct labor to produce twenty square feet of curtain is a useful piece of information.

Summary Definition
Definition of Industrial Engineering Method: It is a way of comparing cost drivers and objects to see how the company can make its operations more efficient.


What are the Basic Steps for Industrial Engineering + Cost Estimation



Understanding Processes and Costs


Receiving and Maintaining Product Designs and Process Plans
Receiving Cost Reports - Periodical Reports and Product Orderwise Reports, Productivity Reports


Analyzing Processes and Costs


Preparing Process Charts and Product Charts based on Shop Observation and Study in standard IE Charts and Diagrams. Analyzing Cost Information and Productivity Reports

Product Improvement, Process Improvement and Cost Reduction

Product Improvement, Process Improvement


Product Industrial Engineering
_________________________

_________________________

Process Industrial Engineering

_________________________


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Preparing new material requirement specifications and resource requirement specifications for products and processes and inputs. Time estimates or measurements prepared.

Preparing Cost estimates and doing Cost measurement after Improvement


Preparing Cost Estimates for Supporting Marketing Efforts/Quotations/Bids



Product Cost Estimates and Supporting Process Cost Estimates are done using the latest reduced costs. When feedback is given by marketing on these bids at various stages, they are studied and understood. The process repeats with the first step.




Engineering Cost Estimating
(http://acqnotes.com/acqnote/tasks/engineering-cost-estimating  Defense acquisition made easy site)



The Engineering Cost Estimating method builds the overall cost estimate by summing detailed estimates done at lower levels of the Work Breakdown Structure (WBS). It’s a technique where the system being costed is broken down into lower-level components (such as parts or assemblies), each of which is costed separately for direct labor, direct material, and other costs. The estimates for direct labor hours are done using analyses of engineering drawings, standard time data and contractor or industry-wide standards.

Engineering estimates for direct material have to be made for  raw materials and purchase parts based on drawings and "make or buy" decision. The remaining elements of cost (overheads including specific items such as quality control) may be expressed in terms of the direct labor and material costs. The  cost estimates at lower component level  are aggregated or totaled and hence the method is called “bottoms-up” estimate). The use of engineering estimates requires extensive knowledge of a system’s (and its components’) characteristics both product design and process plan, and lots of detailed time study and cost study data.

Because of the high level of detail, each step of the work flow should be identified, measured, and tracked, and the results for each outcome should be summed to make the point estimate.

The  advantages to the Engineering Cost Estimating method include:

The estimator’s ability to determine exactly what the estimate includes and whether anything was overlooked,
That it gives good insight into major cost contributors, and
The details of one product can be transferred to other products.

To do engineering estimating, the product specification must be prepared at component level.
All product and process changes also must be communicated to IE department so that they are  reflected in the estimate


More detailed are available in

Defense Acquisition Guidebook (DAG)
GAO Cost Estimating and Assessment Guide
NASA Cost Estimating Handbook – 2008


https://www.degruyter.com/view/j/eng.2016.6.issue-1/eng-2016-0002/eng-2016-0002.xml

https://www.researchgate.net/publication/223817612_Cost_estimation_in_mechanical_production_The_Cost_Entity_approach_applied_to_integrated_product_engineering

https://onlinelibrary.wiley.com/doi/10.1002/9780470172339.ch88  Ch 88 of IE Handbook Salvendy

https://www.sciencedirect.com/science/article/abs/pii/S0925527305001465

https://hal.archives-ouvertes.fr/hal-00732117/document

http://journals.sfu.ca/ijietap/index.php/ijie/article/view/285/209

https://books.emeraldinsight.com/page/detail/Cost-Engineering-and-Pricing-in-Autonomous-Manufacturing-Systems/

https://books.google.co.in/books?id=6rK1UtCXk5cC&printsec=frontcover#v=onepage&q&f=false



Cost Engineering  Definition of AACE

Cost Engineering is the application of scientific principles and techniques to problems of estimation; cost control; business planning and management science; profitability analysis; project management; and planning and scheduling.

Total Cost Management
Total cost management is that area of engineering practice where engineering judgment and experience are used in the application of scientific principles and techniques to problems of business and program planning; cost estimating; economic and financial analysis; cost engineering; program and project management; planning and scheduling; cost and schedule performance measurement, and change control.

Simply stated, it is a systematic approach to managing cost throughout the life cycle of any enterprise, program, facility, project, product, or service. This is accomplished through the application of cost engineering and cost management principles, proven methodologies, and the latest technology in support of the management process.

http://web.aacei.org/about-aace/what-is-cost-engineering
Cost Engineering: New Profession - https://www.jstor.org/stable/pdf/40225654.pdf




Saturday, November 23, 2019

BEL - Industrial Engineering Department




INDUSTRIAL ENGINEERING DEPARTMENT
INDUSTRIAL ENGINEERING MANAGER
RESPONSIBILITIES AND DUTIES

Analyse and evaluate efficient working of all projects and administer all processes and methods according to required supply standards and systems.

 Assist to organize and approve all labour and supply cost annually and prepare reports to measure all labour performance. 

Analyse all product costs and assist to reduce all negative variance on same and prepare strategies to reduce labour and wastage in all engineering projects.

 Assist Industrial Engineering department to design business plans and develop salary for all employees and prepare all required reports on weekly and monthly basis and manage all communication with production management.

Develop salary model budgets for all industrial engineering processes and provide support to all world class manufacturing facilities and analyse all waste elimination plans and develop appropriate factory flow analysis on processes. 

Maintain and update knowledge for all manufacturing engineering processes and design all processes for manpower and associate program and monitor all productivity and ensure compliance to all safety standards.

Evaluate and perform investigation on all variances for all planned and actual results for industrial processes and maintain track of all information and ensure integrity of all results for processes.

Supervise reporting processes on everyday basis and manage everyday activities and ensure adherence to all fiscal budgets and prepare strategic models.

https://vdocuments.mx/summer-internship-report-bharat-electronics-ltd.html


https://www.slideshare.net/bhaumikamber/bharat-electronics-limited-bel-training-report


https://www.slideshare.net/vishalkumargupta/bel-project-report

https://www.slideshare.net/RaghwendraKushwaha/training-report-bel-gzb

Friday, November 22, 2019

T/R Module - Transmitter - Receiver Module



https://www.microwaves101.com/encyclopedias/transmit-receive-modules


 The classic T/R module that made high-performance X-band phased arrays possible cost on the order of $1000 each, which prevented widespread adoption of the technology. Various efforts by DARPA have attempted to bring the price down to $100.


GaN-based Components for Transmit/Receive Modules
in Active Electronically Scanned Arrays
Mike Harris, Robert Howard and Tracy Wallace
Georgia Tech Research Institute, 925 Dalney Street, Atlanta, GA 30332
Email: mike.harris  at the rate gtri.gatech.edu
CS MANTECH Conference, May 13th - 16th, 2013, New Orleans, Louisiana, USA

For  a fixed power level, a GaN MMIC can be 1/3-1/4 the size of  an equivalent power GaAs MMIC.  Raytheon has found that, if the  finished GaN wafer (including material) costs 2X that of  GaAs, but yet the GaN MMIC is 1/3-1/4 the size of the GaAs MMIC, the resulting GaN solution is only 50-66% the dollars per RF watt generated (To be checked with data in Sturdivant's book).



https://www.radartutorial.eu/08.transmitters/Transmitter%20Modules%20of%20an%20Active%20Antenna.en.html

https://www.microwavejournal.com/articles/28121-an-alternative-to-using-mmics-for-tr-module-manufacture?v=preview

https://www.researchgate.net/publication/224652232_Design_of_TR_module_for_the_wideband_active_array_antenna

https://www.tandfonline.com/doi/abs/10.1080/02726343.2016.1158617?scroll=top&needAccess=true&journalCode=uemg20




Optimization

https://ec.europa.eu/jrc/en/publication/eur-scientific-and-technical-research-reports/optimization-techniques-mimo-radar-antenna-systems


https://www.hindawi.com/journals/mpe/2014/946817/


BEL facility Bengaluru

Automated Transmit/Receive Module Assembly Line consisting of die-attach & wire-bonding lines to increase the X-Band TR Modules production capacity.


T/R Module Design


T/R-module technologies today and possible evolutions
Conference Paper (PDF Available) · November 2009
https://www.researchgate.net/publication/224127103_TR-module_technologies_today_and_possible_evolutions

APPLICATION NOTE
LTCC T/R X-Band Module With a Phased-Array Antenna
This application example describes the steps to design a transmit/receive (T/R) module with a 2x2 phased-array antenna operating in the 8-12 GHz frequency range. Several innovative capabilities within the NI AWR software are highlighted, including multi-technology and circuit/system co-simulation, as well as phased-array modeling.

https://www.awr.com/resource-library/ltcc-tr-x-band-module-phased-array-antenna

Thursday, November 21, 2019

Prof. Rick Sturdivant - T/R Modules



Rick Sturdivant, Ph.D.
Assistant Professor, Department of Engineering and Computer Science
Adjunct Professor, Department of Mathematics, Physics, and Statistics
https://www.apu.edu/clas/faculty/ricksturdivant/


https://www.mtt.org/profile/rick-sturdivant/


He is a recognized expert in the field of Transmit/Receive (T/R) modules and phased arrays. Sturdivant has been awarded seven U.S. patents and has four pending.

Sturdivant is the author/co-author of several books and book chapters, including: RF and Microwave Microelectronics Packaging II (Springer Publishing, 2017); Transmit Receive Modules for Radar and Communication Systems (Artech House, 2015); Hands On Guide To Heat Transfer For Microwave and Millimeter-wave Elect. (​ebook, 2015); Microwave and Millimeter-wave Electronic Packaging (Artech House, 2013); and RF and Microwave Electronic Packaging, Chapter 1 (Springer Publishing, 2010).

Wednesday, November 20, 2019

MMIC Technology - Cost Estimation and Reduction - Industrial Engineering - Articles and Cases



_______________

_______________
https://www.youtube.com/watch?v=-iRnDxCSUNI
Oct 2016


MMICs - Monolithic microwave integrated circuits


Cost models attribute 50 to 75% of cost AESA (active electronically scanned array ) to antenna. Within antenna 50% of the cost is attributed to T/R modules./

AESAs have a price of $175 million for array face. Hence the price of T/R modules in an AESA can be $44 million to $65 million. Ground based arrays can have 25,000 T/R modues. Hence each T/R module may have a price of $1760 to $2600. MMICs account for 50% of the TR module cost.

Overall yields of 60 to 70% are considered normal from wafer to MMICs.

GaAS PHEMT or GaN HEMT

Within $1760, the MMIC may cost $700, HPA $350 and rest purchased items and assembly cost.
Touch labor has to be contained below $262 per module.

Breakup of T/R module cost:

MMIC: 40%
Purchased part: 20%
Assembly : 15%
Test: 10%
Qualification: 15%

So MMIC: 40% of 1750 = $700. 50% of it is high power amplifier (HPA) = $350.

Raytheon supported low cos flat panel X-band array using COTS type PCBs and demonstrated four TR channels on a common SiGe BiCMOS substrate at a reported T/R channel cost of $4.
https://books.google.co.in/books?id=jESPCwAAQBAJ&pg=PA205#v=onepage&q&f=false

Cost Factors of Fabricating a MMIC wafer

Labor -  11% of the Manufacturing Cost
Machine related consumables and energy - 43%  of   the Manufacturing Cost
Depreciation - 10%
Taxes - 10%
SG&A - 15%
Profit - 11%

Machine related consumables and energy - 43%  of   the Manufacturing Cost  include cost of consumables, spare parts, materials (including cleanroom garments, wipes, face masks and tweezers) production control and facilities (power, deionized water and gas scrubbers).







NEWS RELEASE:

 Plextek RFI unveils phased array GaN MMIC reference design

CAMBRIDGE, UK: 13 July 2016 —Plextek RFI, a UK design house specialising in microwave and millimetre-wave IC design, has announced a new reference design for a GaN power amplifier (PA) MMIC for use in X-band active phased array radar applications.

“Active phased arrays require numerous PAs, which need to have high efficiency, and to have a small size and relatively low cost,” said Liam Devlin, CEO of Plextek RFI. “Our new design has a die size of only 1.5mm x 2mm, which means around 2,300 PAs can be fabricated on a single 4-inch (100mm) diameter wafer. This makes the cost very competitive compared with other commercially-available MMICs offering this level of RF output power.”

The X-band GaN PA MMIC covers 9.0 – 11.5GHz and delivers 7W (+38.5dBm) of RF output power from a +29dBm input, with a Power Added Efficiency (PAE) of 42%. This means that it can be driven by readily available GaAs parts when used as the output PA stage.

Plextek RFI designed the MMIC using Keysight ADS 2015, and it was manufactured by UMS on its 0.25µm gate length GaN-on-SiC process (GH25).

“As the IC is designed and manufactured in Europe, it will have the added advantage of not being subject to US export control,” added Liam Devlin.
https://www.plextekrfi.com/about-us/press/

How to save money by using custom design GaAs MMICs
August 23, 2010 | Liam Devlin, Plextek Ltd
https://www.plextekrfi.com/wp-content/uploads/custom_gaas_mmics.pdf

Same as above in a different link
https://www.electronicsweekly.com/news/business/finance/can-custom-designed-mmics-reduce-microwave-systems-costs-2013-10/

https://en.wikipedia.org/wiki/Monolithic_microwave_integrated_circuit

Practical MMIC Design
Steve Marsh
Copyright: 2006
Pages: 376
https://us.artechhouse.com/Practical-MMIC-Design-P1009.aspx

MMIC Design Techniques for Low-Cost High-Volume Commercial Modules
Abstract:
This paper presents several MMIC design techniques that focus on module cost reduction and general MMIC component requirements relative to point-to-point and point-to-multipoint terrestrial, as well as two-way satellite, low-cost high-volume communication module needs. Currently, MMIC vendors concentrate on improving performance and reducing MMIC cost. Low-cost high-volume modules impose additional requirements relating to MMIC compatibility with module volume production processes. The MMIC design techniques discussed include: circuit compaction, use of external support components, maximizing symmetry, reduction of external connections, compatibility with automatic bonding machines, compatibility with automatic pick-and-place machines, and standardizing RF probe types. General MMIC requirements relative to module needs for both terrestrial and satellite communication links are also discussed.
Published in: 2003 33rd European Microwave Conference
Date of Conference: 2-10 Oct. 2003
https://ieeexplore.ieee.org/document/4143160

Design GaAs MMICs for best price and performance values
Atkinson, Bobby
Though the manufacturing advantages of monolithic integration and the emergence of GaAs foundaries have resulted in low-cost GaAs MMIC technology, further cost reduction can be achieved by using a foundary's standard line of circuit cells. By using a PC-based workstation with CAD software, it is possible, however, to fabricate a custom MMIC design for $10,000 or less. As an example, this low-cost approach was applied to the design and fabrication of a Ku-band oscillator. Criteria useful for selecting a good foundary are outlined, and attention is focused on MMIC computer-aided-engineering tools. A design process on an Apollo-based MMIC workstation is described and compared with that on a PC-based workstation, and protocols for exchanging data between PCs and mainframes are outlined.


Publication:
Microwaves & RF (ISSN 0745-2993), vol. 30, Feb. 1991, p. 93, 94, 96, 98, 99.
 Pub Date: February 1991
https://ui.adsabs.harvard.edu/abs/1991MicWa..30...93A/abstract



Suppliers

MMIC (Monolithic microwave integrated circuit) devices offering includes ultra-wide band (UWB) power amplifiers (PA), low noise amplifier (LNA), mixers and gain blocks, drive amps, IF ICs, dividers, discrete devices and switches and other RF ICs, available in variety of package sizes or Bare Die to fit your requirements.


Our MMIC products offer substantial advantages such as ESD 4,000 volt, MSL 1, high quality and uniformity, enhanced band width 10MHz to 65GHz, 100% lead-free green products (RoHS compliant), higher performance, temperature compensated bias circuit, friendly packaging, MTBF over 100 years and more.
https://www.hypertech.co.il/product/mmic-devices/


https://www.custommmic.com/news/rounding-up-our-best-gan-rf-power-amplifier-mmics/


https://www.northropgrumman.com/BusinessVentures/Microelectronics/Products/Pages/GaNPowerAmplifiers.aspx

https://www.qorvo.com/innovation/technology/gan

http://rfhic.com/img/Guide.pdf


Research

The ilities of a system are often called life cycle properties.
settings
Packageability as an ‘Ility’ for Systems Engineering
by Rick L. Sturdivant 1,* andEdwin K. P. Chong
Systems 2017, 5(4), 48; https://doi.org/10.3390/systems5040048
https://www.mdpi.com/2079-8954/5/4/48/htm

Yi-Qun Hu, Hao Luo, Yong-Heng Shang and Fa-Xin Yu, 2014. Design of a Highly Integrated Front-End K-Band TR Module Based on LTCC Technology for Phased-Array System. Information Technology Journal, 13: 165-170.
https://scialert.net/fulltext/?doi=itj.2014.165.170

Automatized synthesis of microwave monolitic integrated circuits with spatial and astronomy applications
Start date 1 January 2007  End date  31 December 2008

Objective
In designing MMICs, the hardest problem is to select MMIC's schematic and topology to satisfy performance specifications. This task needs very qualified designers that know electronics, microwaves and technology. The MMIC design is now based on the multiple simulation and optimization of different circuit variants, such the process is very labor- and time-consuming and may lead to non-optimal solutions. This project focuses on investigating and developing methods and software for the direct synthesis of passive and active MMICs from circuit requirements. The project will be based on the new high-frequency network synthesis approaches. The methods and software developed will allow the automatic or interactive determination of MMIC's schematic and topology directly from requirements using exact models of MMIC elements. For implementing the proposed approach to MMIC design, fast MMIC element models will be constructed for specific MMIC production processes. It is planned to build fast polynomial and neuro-network models firstly for GaAs OMMIC ED02AH process and then for another GaAs, InP, SiGe or CMOS European processes that will be selected by partner teams. Within this project, it is supposed to implemented several tools for interactive and automatic synthesis of MMIC passive and active microwave circuits: LOCUS, a tool for the "visual" design of passive matching/compensated networks, GENESYN, a GA-based tool for the synthesis of matching networks, and GENEAMP, a tool for the automatic synthesis of transistor amplifiers using GAs. Also, it is planned to develop two additional software tools: SHIFTER for designing phase shifters, and IMCON for designing negative impedance converters with application to microwave active filters. It is planned to integrate MMIC synthesis tools in such the popular simulators as Microwave Office and ADS. This task supposes the careful estimation and validation of techniques, software tools, and MMIC element models developed. For this, the design and implementation of several extreme-quality MMICs with using these techniques and tools (such as low-noise and power amplifiers, phase shifters, impedance converters, and active filters) are planned. In particular, MMIC designs for spatial, astronomy and low-noise applications will include several designs with OMMIC (GaAs), NGC Indium Phosphide (InP) and WIN (GaAs). Also, as these III/V processes have difficulty meeting the cost targets and high integration density, Silicon processes will therefore be investigated with AMS and IHP (www.ihp-microelectronics.com) in a SiGe process with frequency > 200 GHz but also with UMC in a CMOS process. The designs will be based on the SOC concept integrating amplifying and filtering functions (active filters) on a single ship. In designing negative impedance converters and active filters, the specific original design techniques of XLIM group based on the "impedance profile" will be used.

The benefits and challenges of using GaN technology in AESA radar systems
MARIO LAMARCHE, MERCURY SYSTEMS


Google Books


Pseudomorphic HEMT Technology and Applications
R.L. Ross, Stefan P. Svensson, Paolo Lugli
Springer Science & Business Media, 06-Dec-2012 - Science - 350 pages

PHEMT devices and their incorporation into advanced monolithic integrated circuits is the enabling technology for modern microwave/millimeter wave system applications. Although still in its infancy, PHEMT MIMIC technology is already finding applications in both military and commercial systems, including radar, communication and automotive technologies. The successful team in a globally competitive market is one in which the solid-state scientist, circuit designer, system engineer and technical manager are cognizant of those considerations and requirements that influence each other's function.
This book provides the reader with a comprehensive review of PHEMT technology, including materials, fabrication and processing, device physics, CAD tools and modelling, monolithic integrated circuit technology and applications. Readers with a broad range of specialities in one or more of the areas of materials, processing, device physics, circuit design, system design and marketing will be introduced quickly to important basic concepts and techniques. The specialist who has specific PHEMT experience will benefit from the broad range of topics covered and the open discussion of practical issues. Finally, the publication offers an additional benefit, in that it presents a broad scope to both the researcher and manager, both of whom must be aware and educated to remain relevant in an ever-expanding technology base.
https://books.google.co.in/books?id=En71CAAAQBAJ



Wafer Cost - Estimation and Historical Record


Lecture 5: Cost, Price, and Price for Performance - BNRG
http://bnrg.eecs.berkeley.edu/~randy/Courses/CS252.S96/Lecture05.pdf

Cost per Wafer
http://smithsonianchips.si.edu/ice/cd/CEICM/SECTION2.pdf

Tuesday, November 19, 2019

Machines and Tools Related Methods Efficiency Analysis - Machine Work Study


Machine Work Study - Machines and Tools Related Efficiency/Productivity Analysis


The machines, accessories and tools  used to perform the operation needs to analysed logically to identify process improvement opportunities to increase productivity and engineering has to be done to modify the process to use new equipment, accessories, tools and modified equipment, accessories or tools.

_______________

_______________


_______________

________________

Some Questions regarding Machines, Tools and Equipment - Introduction

Can a foot device be arranged so that an operation now performed by hand can be done by foot?
Are raw materials properly placed? Are there racks for pans of material and containers for smaller parts? Can the parts be secured without searching and selecting? Are the most frequently
used parts placed in the most convenient location? Are the handling methods and equipment satisfactory? Would a roller or a belt conveyer facilitate handling? Can the parts be placed aside by means of a chute?


Is the design of the apparatus the best from the viewpoint of manufacturing economy? Can the design be changed to facilitate machining or assembly without affecting the quality of the apparatus? Are tools designed so as to insure minimum manipulation time? Can eccentric clamps or ejectors be used?
Is the job on the proper machine? Are the correct feeds and speeds being used?  Would a bench of special design be bettor than a standard bench? Is the work area properly laid out?

Such questions examine th emachines, equipment and related aspects.


Relation of Machine Work Study - Industrial Engineering  to Quality. Industrial Engineering and a method of it, machine work study focus primarily on  eliminating waste and reducing costs. In so doing, it is imperative that nothing should be done to impair the quality of the finished product or
its saleability. F.W. Taylor particularly stated it explicitly and also in product industrial engineering method, value engineering L.D. Miles stated it explicitly.  Industrial engineers exist and do their work to enhance the competitive position of his company's products, he quite naturally must take a keen interest in the factor of quality. Products of superior quality outsell products of inferior quality, other things being equal; hence, an improvement in quality is always desirable and efforts to preserve it are made by IEs.  Industry engineer is quite likely to discover ways of making the product better. In  addition, because he eventually sets up working methods that are easy, efficient methods, and because he trains all operators to follow those methods, a higher and more uniform quality of workmanship results than where each operator is left to develop methods for himself. As a result, therefore, methods study either of machine work or human work tends to raise the quality of the finished product.



Industrial engineers examines every detail in the engineering system or production system,  that is likely to affect operating time and cost. Experience leads to the recognition of the points at which the greatest possibilities for improvement lie, and the major part of the study will be made on them.

In a machine shop, the term "setup" is loosely used throughout industry to signify the workplace layout, the adjusted machine tool, or the elemental operations performed to get ready to do the job and to tear down after the job has been done. More exactly, the arrangement of -the material, tools, and supplies that is made preparatory to doing the job may be referred to as the " workplace layout." Any tools, jigs, and fixtures located in a definite position for the purpose of doing a job may be referred to as "being set up'  or as "the setup." The operations that precede and follow the performing of the repetitive elements of the job during which the workplace layout or setup is first made and
subsequently cleared away may be called "make-ready" and "put-away" operations. For the sake of clearness, the more exact phraseology will be used throughout this book, although the workplace layout, the setup, and the make-ready and putaway operations are all considered under item 6 on the analysis sheet.

The workplace layout and the setup, or both, are important because they largely determine the method and motions that must be followed to do the job. If the workplace layout is improperly made, longer motions than should be necessary will be required to get materials and supplies. It is not uncommon to find a layout arranged so that it is necessary for the operator to take a step or two every time he needs material, when a slight and entirely practical rearrangement of the workplace layout
would make it possible to reach all material, tools, and supplies from one position. Such obviously energy-wasting layouts are encountered frequently where methods studies have not been made and when encountered serve to emphasize the importance of and the necessity for systematic operation Analysis.

The manner in which the make-ready and put-away operations are performed is worthy of study, particularly if manufacturing quantities are small, necessitating frequent changes hi layouts and setups. On many jobs involving only a few pieces, the time required for the make-ready and put-away operations is greater than the time required to do the actual work. The importance of studying carefully these no-nrepetitive operations is therefore apparent. When it can be arranged, it is often advisable to have certain men perform the make-ready and put-away operations and others do the work. The setup men become skilled at making workplace layouts and setups, just as the other men
become skilled at the more repetitive work. In addition, on machine work it is usually possible to supply them with a standard tool kit for use in making setups, thus eliminating many trips
to the locker or to the toolroom.

The tool equipment used on any operation is most important, and it is worthy of careful study. Repetitive jobs are usually tooled up efficiently, but there are many opportunities for savings
through the use of well-designed tools on small-quantity work which are often overlooked. For example, if a wrench fits a given nut and is strong enough for the work it is to do, usually
little further attention is given to it. There are many kinds of wrenches, however. The list includes monkey wrenches, openend wrenches, self-adjusting wrenches, socket wrenches, ratchet wrenches, and various kinds of power-driven wrenches. The time required to tighten the same nut with each type of wrench is different. The more efficient wrenches cost more, of course, but for each application there is one wrench that can be used with greater over-all economy than any other. Therefore, it pays to study wrench equipment in all classes of work. The same remarks apply to other small tools.

Jigs, fixtures, and other holding devices too often are designed without thought of the motions that will be required to operate them. Unless a job is very active, it may not pay to redesign an inefficient device, but the factors that cause it to be inefficient may be brought to the attention of the tool designer so that future designs will be improved.


Under the head of "Setup," a description is given of the workplace layout and the arrangement of tools, fixtures, and so on. This description may be written if the setup is simple, but a photograph will be found more useful and infinitely clearer if the arrangement is at all complex. It would require several hundred words, for example, to describe the workplace layout pictured in Fig. 44, and even then it would be difficult to visualize the layout in its entirety. The picture tells the story at a glance and shows clearly the arrangement of the workplace at the time of the analysis.


When the machine setup is being considered, the tool equipment also is examined. The tools and the setup are so closely related that it is difficult to separate them, and nothing is gained by attempting to do so. In examining the setup of the milling machine, it is noted at once that a standard vise and a special side cutter are used. A description of these items of tool equipment is therefore recorded. Often, when tool equipment is examined with thoughts of job improvement uppermost in mind,
suggestions for improving the tool equipment will immediately occur to the analyst. These should be recorded as they arise, even though they may reoccur during the consideration of items 7 and 9. It is better to duplicate the small amount of writing involved than to risk the possibility of overlooking a good idea.



More Detailed Questions on Machine, Equipment and  Tools



The tools  and equipment used to perform the operation needs to analysed logically. The following questions are the sort that will lead to suggested improvements:

1. Is the machine tool best suited to the performance of the operation of all tools available?

2. Would the purchase of a better machine be justified?

3. Can the work be held in the machine by other means to better advantage?

4. Should a vise be used?

5. Should a jig be used?

6. Should clamps be used?

7. Is the jig design good from a motion-economy standpoint?

8. Can the part be inserted and removed quickly from the jig?

9. Would quick-acting cam-actuated tightening mechanisms be desirable on vise, jig, or clamps?

10. Can ejectors for automatically removing part when vise or jig is opened be installed?

11. Is chuck of best type for the purpose?

12. Would special jaws be better?

13. Should a multiple fixture be provided?

14. Should duplicate holding means be provided so that one may be loaded while machine is making a cut on a part held in the other?

15. Are the cutters proper?

16. Should high-seed steel or cemented carbide be used?

17. Are tools properly ground?

18. Is the necessary accuracy readily obtainable with tool and fixture equipment available?

10. Are hand tools pre-positioned ?

20. Are hand tools best suited to purpose?

21. Will ratchet, spiral, or power-driven tools save time?

22. Are all operators provided with the same tools?

23. Can a special tool be made to improve the operation?

24. If accurate work is necessary, are proper gages or other measuring instruments provided?

25. Are gages or other measuring instruments checked for accuracy from time to time?

Because of the wide variety of tools available for different kinds of work, this list could be extended almost indefinitely with specific questions. Foundries, forge shops, processing industries, assembly plants, and so on all have different kinds of tools, and different questions might be asked in each case. The list given above, drawn up principally and by no means completely for machine work, will indicate the kind of searching, suggestive questions that should be asked. A special list might well be drawn up by each individual plant to cover the kind of tools that might be advantageously applied upon its own work.


Equipment.—A study of existing equipment may suggest changes and improvements or repairs. Machine operations should be those which combine economy with uniformity of standard quality. Standard times and methods are dependent upon standardization of machines within each class (using the best machines for operations), and the maintenance of normal conditions with respect to their upkeep. (https://nraoiekc.blogspot.com/2019/07/operation-study-arthur-g-anderson-1928.html)

Tools:  For the most part,  it may be said that the tools do function properly from the standpoint of the finished job. But from a productivity angle, industrial engineer has to examine the productivity possible from the existing tool and has to compare it with productivity possible from alternative tools to decide the appropriate alternative. Industrial engineers have to receive information regarding new tools from purchase department, representatives of organizations selling tools, consultants and technical literature being procured by the company. Industrial engineers have to monitor technology and engineering developments on a continuous basis and have to set up libraries for their departments or there have to sections within the company library for industrial engineering materials.

Similarly,  whether, the jigs and fixtures etc. function properly from a motion-economy standpoint is subject to evaluation by industrial engineers. The tool designer is usually more concerned with making a tool that will do a certain job than he is with the motions that will be required to operate it. Therefore, unless he has made a study of the principles of methods engineering or has had the importance of motion economy impressed upon him in some other way, it is probably safe to say that the motions required to operate the tool are the last thing he thinks of.

There can be alternative work holding methods  that require less  time to use.  The common machine vise takes a lot of time set up the work piece.  The quick-acting vise is far superior. On machining operations where the cutting time is short, it will save 20 to 40 per cent of the total operation time. The jaws of the vise are cam-actuated. They are tightened by moving the two levers in opposite directions which conforms to the principles of motion economy. They hold securely without hammering on the levers. They are adjustable to a variety, of sizes of work. In short, they possess many real advantages over the standard vise.

Suggestions that will improve the quickness of operation of tools should be made to tool designers as they are conceived. If they are presented with a summary of the yearly saving in dollars and cents that they will effect, interest in better tool design from a use-time standpoint will be aroused. Tool designers as a group are clever and ingenious, and if the importance of reducing the time required to operate tools is clearly demonstrated, they will be able to assist materially toward this end by producing more suitable designs.

Hand Tools. Too little attention to the hand tools used upon even the more repetitive operations. There is choice available in even simple hand tool as a screw driver from productivity point of view.  Screw drivers vary widely in design, and some are more suitable than others. Screw drivers come in a number of different styles. There are the solid screw drivers, the ratchet screw drivers, the spiral screw drivers, and the various types of power-driven screw drivers. Even the variation among screw drivers of a given type is tremendous. They vary in size, of course, but in addition they vary in about every other way imaginable. The handles vary in diameter, length, cross section, shape, and nature of gripping surface. Points are wide, narrow, blunt, sharp, taper toward the point like a wedge, or are narrower right above the point than at the point. A lately introduced type has a special point to fit a special screw head which offers many advantages. When all these factors are considered, the choice of the screw driver is important from efficiency or productivity point of view. 

There is a screw driver that is better for a given application.  For medium work with the conventional screw-head if a solid screw driver is to be used, the one with the largest cylindrical handle which can be comfortably grasped by the operator should be chosen. The handle should, of course, be fluted to prevent slipping. The diameter of the handle will vary with the size of the operator's hand, but two or three standard sizes are sufficient for most hands. The diameter of the handle should be large, because the larger the handle within the limits of the human hand, the more easily can a given torque be applied. To prevent slipping, the point should not be wedge-shaped but should be slightly larger at the point than just above it. 

If many screws have to be driven, a ratchet, spiral, or power-driven screw driver can often be used to good advantage. If many screws of the same size are to be driven, a piece of hardened tubing slipped over the end of the screw-driver point will make it much easier to locate the screw driver in the slot.

The same sort of searching analysis can be made for every type of hand tool used. Wrenches, hammers, chisels, saws, scissors, knives, pliers, and drills all come in a great variety of styles. Standardization on a limited number of the better styles within a plant will tend to prevent the use of the more inefficient tools. Tests must be made to determine which styles are actually the most efficient. Time taken for the element is the decision criterion.

Judgment must be used, of course, in determining the amount of time that can economically be spent in analyzing the tools used on any one job. Unless a job is highly repetitive, it will not pay to try to discover the best screw driver for that particular job. Instead, the whole subject of hand tools including screw drivers may be investigated in a general way, and good tools may be adopted for standard use. The tool supply should be plentiful, for it is not uncommon to see operators not only using the wrong size of tool, but also using a chisel for a hammer or a screw driver for a crude chisel merely because the proper tool is not available. An insufficient supply of proper tools may reduce the amount expended for tools, but it will prove costly in the long run.


Setup - Workplace Layout

The order in which tools are set up in a turret lathe, for example, will determine the order in which the various machining operations are performed. The position in which material is placed with respect to the point of use will determine the class and the length of the motions required to secure it.

Before any work can be done, certain preliminary or "make ready" operations must be performed. These include such elements as getting tools and drawings, getting material and instructions, and setting up the machine or laying out material and tools about the workplace. When the operation itself has been completed, certain clean up or "put-away" elements must be done such as putting away tools and drawings, removing finished material, and cleaning up the workplace or machine.



Questions on "Make-ready" and "Put-away" Elements. The procedure followed to perform the
'make-ready' and "putaway" elements may carry the operator away from his workplace and should be questioned closely. In small-quantity lot work, these operations may consume more time than productive operation work. The necessity for trips to other parts of the department should be minimized.

Questions which will lead to suggestions for improvement of "Make-ready" and "Put-away" Elements  are:

1. How is the job assigned to the operator (job card or ticket issue to operator)?
2. Is the procedure such that the operator is ever without a job to do (delays in giving job ticket)?
3. How are instructions imparted to the operator?
4. How is material secured?
5. How are drawings and tools secured?
6. How are the times at which the job is started and finished checked?
7. What possibilities for delays occur at drawing room, toolroom, storeroom, or time clerk's office?
8. If operator makes his own setup, would economies be gained by providing special setup men?
9. Could a supply boy get tools, drawings, and material?
10. Is the layout of the operator Js locker or tool drawer orderly so that no time is lost searching for tools or equipment?
11. Are the tools that the operator uses in making his setup adequate?
12. Is the machine set up properly?
13. Is the machine adjusted for proper feeds and speeds?
14. Is machine in repair, and are belts tight and not slipping?
15. If vises, jigs, or fixtures are used, are they securely clamped to the machine?
16. Is the order in which the elements of the operation are performed correct?
17. Does the workplace layout conform to the principles that govern effective workplace layouts?
18. Is material properly positioned?
19. Are tools prepositioned?
20. Are the first few pieces produced checked for correctness by anyone other than the operator?
21. What must be done to complete operation and put away all equipment used?
22. Can trip to return tools to toolroom be combined with trip to get tools for next job?
23. How thoroughly should workplace be cleaned?
24. What disposal is made of scrap, short ends, or defective parts?
25. If operation is performed continuously, are preliminary operations of a preparatory nature necessary the first thing in the morning?
26. Are adjustments to equipment on a continuous operation made by the operator?
27. How is material supply replenished?
28. If a number of miscellaneous jobs are done, can similar jobs be grouped to eliminate certain setup elements?
29. How are partial setups handled?
30. Is the operator responsible for protecting workplace overnight by covering it or locking up valuable material?


It may be seen that an analysis of "make-ready " and "put-away" operations covers a rather wide field. Some are related to operator work also. But they are mentioned here as they form part of set up and make ready the equipment step.  Some of the steps are standard for every job; and after it has been thoroughly analyzed for one job and improved as much as possible, it need not be considered so carefully again.  Therefore, the subject should receive a thorough analysis at least once, and preferably so that irregularities will not be permitted to creep in and become standard practice more often, say at least every 6 months.



Make Ready - Allocation of Jobs and Giving Instructions


The methods followed in giving out jobs differ widely throughout industry. Some procedure for telling an operator what job he is to work upon next must be provided. In some cases, material to be processed is placed near the work stations of a number of operators. The operators go to the material and themselves select the jobs they wish to do. This procedure has certain serious disadvantages. Some jobs are more desirable from the operator's standpoint than others. They may be easier or lighter or cleaner,  some jobs may carry looser rates than others, thus permitting higher earnings for a given expenditure of effort. If the operators are allowed to pick their own jobs, those who have stronger characters or are physically superior are likely to get the best jobs, and the weaker must take what is left. The least desirable jobs will be slighted altogether as long as there is any other work to do, which causes these jobs to lag and become overdue. There is no assurance that the operators will get the jobs for which they are best suited, considering the group as a whole.
Where the group system is used, these difficulties are minimized, but principally because the group leader assumes a function of management and hands out the work to the members of his group. The group knows that sooner or later it will have to handle all jobs sent to it, and so there is less tendency to slight undesirable work. In the interests of good performance as a group, the skilled men will do the more difficult jobs, leaving the easier tasks to the new or less skilled men. In short, the entire
situation is changed; when the group system is used, the selection of jobs may be left to the workers themselves.


Another common procedure is for the foreman to assign jobs. The foreman knows the work, and he knows his men. Therefore, he is in a good position to distribute the work so that it will be performed most effectively. The chief difficulty with this arrangement is that the modern foreman is so loaded
with duties and responsibilities that he often does not have time to plan his work properly. In moments of rush activity, instead of always having several jobs ahead of each operator, he is likely
to assign jobs only when men run out of work. When a man comes to him for a job, he is likely to glance at the available work and assign the first job he sees that he thinks the operator can do. It may not be the one best suited to the operator; perhaps even more important, it may not be the job that fits most important from a delivery standpoint.


With regard to this last point, in order to get work through the shop on schedule, the planning or production department must work closely with the foreman. Usually, chasers or expediters call to the attention of the foreman the job that is required next. If there are only a few rush jobs, the foreman may be able to have them completed as desired. In times of peak activity, however, when the shop is overloaded, all jobs become rush jobs. Each expediter has a long list of jobs to be completed at once.
Considerable pressure is brought to bear upon the foreman to get out this job and that, and he is likely to find himself devoting time to detailed production activities that could better be spent on taking steps to relieve the congestion.

In most up-to-date plants, the foreman is regarded as a very important man. He is called into conferences and meetings and often participates in educational programs. He is, therefore, away from his department at intervals and, if he has the responsibility of giving out jobs, must give out enough work to last until he returns. If he is called away suddenly or is unexpectedly detained, operators will run out of work. Then they either lose considerable time and hence money which creates dissatisfaction, or they help themselves to another job. If this latter practice is countenanced in a time of emergency, there is a danger that it will soon develop into a standard practice. If men get their own
jobs, the foreman is relieved of a certain amount of work and, if he is otherwise overloaded, may tend to allow operators to select their work with increasing frequency, until all the advantages gained by having the foremen hand out work are lost. The decisions with respect to the order in which jobs are to be put through the shop are made by the planning or production department. Since they know in what order jobs are wanted, it would, therefore, appear that a representative of this department should cooperate closely with the foreman in giving out the work. The foreman may specify the men who are to work on each job when the orders first reach his department, and a dispatch clerk may give the work to the assigned men in the order of its importance from a delivery standpoint. This arrangement is followed in a number of plants.In  typical dispatching station system under the control of the production department, time tickets for each operation on each job are made out in a central planning department and are marked with the date the operation should be completed. The dispatcher arranges these time tickets in his dispatch board. Each group of machines within the department is assigned a pocket  the dispatch board, and each pocket has three subdivisions.

The time tickets are received considerably in advance of the material. They are first filed in a subdivision of the proper machine pockets called the "work ahead " division. The number of tickets in the "work ahead" divisions at any time gives a rough idea of the load on the shop. When material for a given job enters the department, the dispatcher is notified. He then moves the time ticket for the first operation from the "work ahead" division to the "work ready " division. The time tickets in the latter pocket then show the jobs that are actually ready to be worked upon. When an operator completes one job, he goes to the dispatcher's station and turns in the ticket for that job. The dispatcher then gives him another job by taking the time ticket from the "work ready" division and handing it to him. He selects always the ticket marked with the date nearest to the current date and thus gets the work done in the desired order.

When the operator has received notification in one way or another of the job he is to do, he must next secure drawings, tools, and material. The way in which this is done also varies widely. In some cases, the operator must hunt everything for himself. In others, he goes to a tool- or drawing-room window
and waits while an attendant gets what he requires. In still other cases, everything is brought to him, and he does not have to leave his work station. The exact procedure that is followed will depend upon existing conditions; but if it is possible to work out an economical system for furnishing the operator with what he needs at his work station, it is desirable to do so. Besides reducing costs, this procedure increases the amount of time the equipment is utilized and thus increases the productive capacity of the plant. Often a low-rated worker can do the errands of the operators and bring tools, drawings, and materials.

Where the group system is used and no supply boy is available, the group leader commonly gets all necessary supplies and tools. By getting the necessary items for several jobs at one time, he is
able to effect economies.

A conveyer system can be employed and the jobs may be dispatched by the production department in the order wanted, and all material, tools, and drawings can be sent out at the same time on the conveyer. Thus the amount of time spent by the operator in getting ready to make the setup  is reduced to a minimum.

The manner in which instructions are furnished with regard to how the job should be done is worthy of careful consideration. In many cases, no instructions at all are given. The operator is supposed to be familiar enough with the work to know how to do it. If not, he may ask the foreman. When no definite instructions are given or when the foreman gives only brief general advice, the method that the operator follows is likely to be one of his own devising which may or may not be effective. The fact that in so many cases different operators follow different methods in doing the same operation may be traced directly to insufficient instruction. To secure effective performance, the best method must first be worked out and then taught.

Some plants employ instructors or demonstrators to perform the teaching function. If these men know the best methods themselves and are good teachers, good results will be secured. Too often, however, the instructor is merely an experienced operator who knows only such methods as he himself used before he was promoted. Even though he was a highly skilled operator, the chances of his knowing and being able to impart a knowledge of the best methods are small, unless he has received additional
training himself in the principles of methods engineering. If he is a machine instructor, he is likely to teach feeds and speeds and the best way to grind tools, mentioning only briefly, if at all, the arrangement of the workplace and the motions that should be used.

Feeds, speeds, and the grinding of tools all are important, of course, but they constitute only part of the method. A lathe operator, for example, was engaged in turning shafts in an engine lathe. Each shaft had to be stamped with a number. The operator would remove a finished shaft from his lathe, turn to a bench, stamp the number, set aside the shaft, pick up another, and return to his machine. The turning required a long cut under power feed. A much better method is as follows: While a cut is being taken, the operator gets the next shaft to be machined; he places it on the machine ways in a convenient position; as soon as the cut is taken, he removes the finished shaft and inserts the other; he starts the cut and then while the machine is running, stamps and lays aside the finished shaft. Thus, the machine runs nearly continuously, and idle time on the part of both the operator and the machine is reduced.  Instruction in some manner with regard not only to feeds and speeds but also with
regard to the proper motion sequence would be necessary to correct his difficulty.

Instruction sheets can be used to instruct operators and, under certain conditions, their use is not too costly.

Setup.

The setup of the machine and of any tools, jigs, or fixtures used should be studied in detail. The correctness and the adequacy of the setup should first be considered, followed by a brief review of the methods employed to make it. The correct setup is fixed by the nature of the operation, the nature of the part, the requirements of the job, and the mechanical features of the machine. Sometimes, it is possible to do a job in more than one way, and care should be taken to ascertain
that the best way is being used.

Many ingenious ways are tried to extend the time for doing a job during the course of a time study. Some changes are done in setup like belts may be loosened so that they slip under load, or a carbon steel cutter may be used in place of a higher speed alloy. In one incident of a time study  on a milling-machine operation, the operator loosened the bolts slightly that held the vise to the machine table. When the cut was taken, the vise very slowly slid along the surface of the table, and of course, the time for taking the cut was extended. The time-study engineer, checked the feed and length of cut and  found a discrepancy between his data and what the cutting time should be. It was difficult to detect at first where the trouble lay, but the vise eventually reached a point where it was noticeably out of position. Then it was  reset it properly, and then restudied the job. Therefore industrial engineers have to examine the setuup and described it adequately in the standard process sheet.

When the setup is being made, certain tools are usually required. These should be suitable for the purpose. If each operator must make his own setup, he should be provided with the necessary tools. If only one or two wrenches are furnished to a group of 10 operators, for example, the time lost in hunting the wrenches and in waiting for a chance to use them will usually far offset the cost of additional equipment. If setup men are employed to setup machines ahead of the operators, their setup work is to them fairly repetitive work, because they are performing the same elements day after day. It will therefore be desirable to treat it as such and to furnish the setup men with special-purpose quick-acting tools.


The Workplace Layout.

The improvement of the layout of the workplace of the industrial worker is too often overlooked as
a means for effecting operating economies. The layout of the workplace partly determines the method the operator must follow in doing a given task, and it almost wholly determines the motions he must employ.  For this reason, the principles which affect workplace layouts will be discussed briefly.

Two general concepts underlie workplace layouts. The first has to do with the classes of motions that a human being can make. There are five general classes, as follows:

1. Finger motions.
2. Finger and wrist motions.
3. Finger, wrist, and forearm motions.
4. Finger, wrist, forearm, and upper-arm motions.
5. Finger, wrist, forearm, upper-arm, and body motions.

It is usually stated that motions of the lower classes can be made more quickly and with less expenditure of effort than in motions of the higher classes.

The arc which bounds the maximum working area is traced by the fingers when the arm, fully extended, is. pivoted about the shoulder.

The principles of efficient work areas should be applied to all lines of work, for they are universal. It is customary to think of them in connection with bench operations; but they can and should be applied to the arrangement of tools and materials around machines or on work such as molding, forging, and the like, and to the arrangement of levers, hand wheels, and so on, when designing machine-tool equipment.

In work place layout, one of the most glaring faults commonly encountered lies in the arrangement
of containers of raw and finished material. If the placement is left to the operators, a body motion will often be used for getting or laying aside material, because the operator sets the material containers on the floor or the bench or in some other place that is available but not particularly convenient. Industrial engineers can design an arrangement that minimizes motions and fatigue and thus save time and increase productivity.



Put Away. The put-away elements usually consume less time than the make-ready elements. Tools are put away, the setup is torn down, and the workplace is more or less thoroughly cleaned up. Usually, some of the put-away elements can be combined with some of the make-ready elements for the next operation. Tools for one operation, for example, may be returned to the tool room when the tools for the next operation are obtained. The procedure that will prove most economical for the put-away
elements will depend to a large extent upon the manner in which the make-ready elements are performed. Where a number of similar operations are performed on a machine, it is sometimes possible to use 'the same or part of the same setup on two or more jobs. A part that is common to
several assemblies may be ordered separately for each and appear on several different orders. If these orders are grouped, one setup will care for them all. Again, in milling-machine work, for example, it may be possible to use the same cutter for several different jobs. The elements of "get cutter from
toolroom; "place cutter on machine, "remove cutter from machine/ and "return cutter to toolroom" will thus be performed but once for the several jobs.


Where possibilities of this sort exist, provision should be made when setting up the make-ready and put-away routine so that the economies will be made. If the operator does not know what job he is to do next, if he must completely tear down his setup before going for another job, and if neither the foreman nor the dispatcher attempts to group similar jobs, advantage cannot be taken of partial setups. This is wasteful, of course, and every attempt should be made to secure the benefit of partial setups. Whether or not the operator is paid for the complete setup or only for that part which he actually makes depends upon the difficulty in controlling setups and upon whether or not the saving is due to the operator's own initiative.  In either case, more time is available for productive work which is a distinct gain.






Source: Operation Analysis by Maynard & Stegemerten, 1939
Full Knol Book - Method Study: Methods Efficiency Engineering - Knol Book

Modern Developments in Tools

2001

Duraspin Screw Fastening System increases productivity by 31%.
https://www.rsmeans.com/consulting/Senco.pdf


Updated 19 November 2019, 31 July 2019,  5 June 2019, 17 February 2019,  4 July 2015
First published 23 Nov 2011