Tuesday, December 31, 2024

Applied Industrial Engineering - Industrial Engineering 4.0 - Online Course Module

New Industrial Engineering Online Book for 2025.

Modern Industrial Engineering - A Book of Online Readings. PDF File.

Now on Academia-Edu Platform.

https://www.academia.edu/126612353/Modern_Industrial_Engineering_A_Book_of_Online_Readings 


Modules  of Industrial Engineering ONLINE Course

Modules

Applied Industrial Engineering - IE in Various Branches of Industrial Engineering

Industrial engineering is primarily an engineering discipline with productivity orientation. It major application is in incremental improvement of processes that give benefit within one year and hence it became closely allied with management in increasing profits, reducing costs and providing the company with the potential to reduce prices and increase profit. Hence Taiichi Ohno said industrial engineering is profit engineering. If a company is not using IE, it is losing an opportunity.

The application of industrial engineering is in processes of all engineering branches. Engineering activities like product design, production, maintenance of machines in factories, and service of consumer items are important engineering activities. In addition material handling and storage also involve engineering. Unfortunately, industrial engineering profession has not given enough attention to makes its presence in various engineering branches visible and systemic. Only limited attempts were done to create textbooks that discuss IE in specific engineering branches.

Industrial Engineering in Chemical Engineering


Industrial Engineering in Civil Engineering

Industrial Engineering in Computer Engineering and Information Technology

Industrial Engineering in Electrical Engineering

Industrial Engineering in Electronics Engineering

Industrial Engineering in Health Care

Information Systems Industrial Engineering - Information Systems Engineering

Industrial Engineering in Textile Engineering

Applied Industrial Engineering in New Technologies

IE in New Technologies - IE with New Technologies


Implementation of  Industrial Engineering Principles and Techniques in New Technologies (Engineering Processes) and Business Processes

Lesson 433


Lesson 434

435
Industrial Engineering in Data Center Design and Processes


436


437


438


439
Electric Batteries and Productivity Applications. - Productivity and Industrial Engineering (IE) in Battery Manufacturing


441
Productivity Automation Engineering - Automation and Productivity

A Good Example of Applied IE - Improving Processes using New Technologies

Industry 4.0 Technology and Manual Assembly
By Amanda Aljinovic
March 15, 2023

Digital work instructions, cobots, radio frequency identification (RFID), augmented reality (AR) and other Industry 4.0 technologies can help. These technologies are designed to provide cognitive and physical support to people on the assembly line.  How can engineers decide when such technologies are a worthwhile investment?

In a case study, industry 4.0 technologies application in a gear-box assembly line was studied.

Seven Industry 4.0 technologies were considered: RFID, digital work instructions, pick-to-light technology, AR, cobots, automated guided vehicles, and ergonomic manipulators.



Four quantitative criteria were used to rank the technologies: total investment cost, worker effort, workspace utilization and cycle time reduction. 

RFID is one of the most important technologies for identifying and tracking assemblies in a production system. It provides precise information about the locations or states of goods in real-time and serves as a capstone for the establishment of the IoT within production.

Digital instructions are proven to reduce the assembly time and errors with complex assemblies.

Pick-to-light systems use LEDs on racks or shelves to show assemblers where to pick parts for an assembly and how many to retrieve. The lights guide assemblers through each step in the process. These systems are often connected with warehouse management systems.

AR also offers the possibility of significant improvement in cycle time, error rate, mental strain, worker focus.

Cobots are particularly desirable when people are confronted with heavy loads and repetitive, tedious activities. People can share the same workspace with the cobots, allowing managers to allocate tasks in a more flexible, efficient way.

AGVs can eliminate the need for people to transport parts and assemblies to and from the assembly line.

The ergonomic manipulator is an electronic device developed to improve ergonomics at the fifth assembly workstation. The device reduces the amount of physical effort needed to handle heavy components that must be mounted to the gearbox.

This article is a summary of a research paper co-authored by Aljinovic, Nikola Gjeldum, Ph.D., Boženko Bilic, Ph.D., and Marko Mladineo, Ph.D. 


Industrial Engineering 4.0


442

Industrial Engineering 4.0 - IE in the Era of Industry 4.0

New
Training the Next Industrial Engineers and Managers about Industry 4.0.
Arriel Benis, Sofia Amador Nelke, Michael Winokur 
Sensors (Basel). 2021 Apr 21;21(9):2905. doi: 10.3390/s21092905

Excerpts

As a modern discipline, Industrial Engineering and Management (IEM) is at the crossroad of many fields such as engineering and technology, formal and natural science and management science, and human sciences.

Industrial engineering is commonly defined as a domain attending to developing and improving different kinds of business and industrial tasks, e.g., describing a modus operando; and handling milestones of a production. Offering an up-to-date and cutting-edge curriculum is challenging. It is required to consider the curriculum of other engineering specialties to give the students the ability to communicate and be productive with other specialists efficiently. Furthermore, as IEM is a very dynamic field and with the continuous development of new technologies, the students’ training must fit industry needs both locally and globally. 

This section focuses on four courses in the IEM curriculum at HIT and the graduation project that are at the heart of the educational requirements of the fourth Industrial Revolution:

Introduction to algorithmic and Python (Python);

Computer Integrated Manufacturing (CIM);

Introduction to Internet of Things (IoT);

Models of Business Intelligence (MBI);

These four courses and the graduation capstone project (GP) are linked to one another and are a part of the third and fourth years of the curriculum. 





443
Industry 4.0 - A Note for Industrial Engineers for Industrial Engineering 4.0 (IE 4.0) 

444
Augmented Reality - Exploration


445
Autonomous Robots - A Note for Industrial Engineers for Industrial Engineering 4.0 (IE 4.0)

446
Data Analytics Period in Productivity Improvement - Productivity Engineering and Management

447
Cloud Computing - Engineering Economic and Financial Analysis

448
IoT Technology - Exploration - Industrial Engineering Point of View

449
Simulation and Forecasting - A Note for Industrial Engineers for Industrial Engineering 4.0 (IE 4.0)

Specific Industries and Technologies

456
Productivity and IE in Tire Manufacturing - Applied Industrial Engineering

457
Industrial Engineering in Health Care

458
Productivity Engineering of Tractors and Agriculture - Smart/Intelligent/Autonomous/IoT Tractors

459
Industrial Engineering of Welding Processes





460
Productivity and IE in Printed Circuit Board Manufacturing

461
Die Casting Productivity - Bibliography

462
Productivity Success Story - Coca Cola

463
Productivity and IE in Motor and Generator Manufacturing

464
Productivity and IE in Motor Vehicle Metal Stamping

465
Productivity and IE in Screw, Nut, and Bolt Manufacturing

466
Productivity and IE in Spring Manufacturing

467
Productivity and IE in Iron and Steel Forging

468
Productivity and IE in Automobile Manufacturing

469
Productivity in Machine Shops - Industrial Engineering and Lean Thinking

470
Productivity and IE in Paint, Coating, and Adhesive Manufacturing

471 
Productivity and IE in Motorcycle and Scooter Manufacturing

472
Productivity and IE in Pharmaceutical and Medicine Manufacturing

473
Grinding - Productivity Science and Productivity Engineering - Opportunities for 2020 and Beyond

474
Productivity and IE in Dies , Jig, and Fixture Manufacturing
 
475
Productivity and IE in Apparel Manufacturing

476
Productivity and IE in Electronic Assembly Manufacturing

477
Productivity and IE in Iron and Steel Pipe and Tube Manufacturing

478

Bosch Automotive - Bursa - Industrial Engineering 4.0 - WEF - McKinsey Light House Plant

Deployed  AI use cases such as close loop process control for hydro-erosion, and upskilling 100% of the workforce.  

They reduced unit manufacturing cost by 9% and improved OEE by 9%.

479
CEAT - Halol, India Plant - Industrial Engineering 4.0 - WEF - McKinsey Light House Plant.

CEAT deployed Fourth Industrial Revolution use cases like advanced analytics to optimize cycle times and digitalization of operator’s touchpoints. 

The site reduced cycle times by 20%, process scrap by 46%, and energy consumption by 15% . 
Overall, this resulted in approximately a 2.5 times increase in export and OEM sales in two years.

480
4. Dr Reddy's - Hyderabad Plant - Industrial Engineering 4.0 - WEF - McKinsey Light House Plant

The site deployed 40+ 4IR use cases by operating in garage mode and leveraging IIoT & democratized platform for advanced analytics. 

It improved manufacturing cost by 43% while proactively enhancing quality and reducing energy by 41%.

481
5. .Ericsson - Lewisville Plant - Industrial Engineering 4.0 - WEF - McKinsey Light House Plant

The use of digital twins led to substantial enhancements: a 25% increase in throughput and a 50% reduction in unplanned downtimes.

482
6. Foxconn - Shenzen Plant - Industrial Engineering 4.0 - WEF - McKinsey Light House Plant


Shenzhen factory uses computer-controlled autonomous manufacturing in the dark, basically without assembly line workers in the production of electrical equipment components used in smartphones. It is  equipped with an automated optimization system for Machine Learning and AI devices, an intelligent self-maintenance system, and an intelligent real-time monitoring system. 

The factory’s production efficiency has been increased by 30%  and the inventory cycle reduced by 15%.


483
7. GlaxoSmithKline (GSK) Hertfordshire Plant - Industrial Engineering 4.0

The GSK plant has applied advanced technologies throughout its manufacturing operation, using advanced analytics and neural networks.  This has improved line speeds at the site by 21%, cut downtime, increased yields, and delivered an OEE (overall Equipment effectiveness) improvement of 10%.

GSK has applied deep-learning image recognition to detect quality defects, and is using artificial intelligence to optimise machine throughput. 

By implementing digital twin technologies, it has boosted capacity by 13%, while cycle time monitoring and the use of digital visualisation tools have cut cycle times by 9%.

484
8. Haier - Hefei Plant - Industrial Engineering 4.0 - Industry 4.0 WEF-McKinsey Lighthouse


Haier’s Hefei air conditioner factory applied advanced algorithms, digital twins, knowledge graphs and other cutting-edge technologies in the research and development (R&D), production and testing of household central AC systems, resulting in a 33% increase in energy efficiency, a 58% drop in the defect rate, a 49% increase in labour productivity and a 22% drop in unit manufacturing costs.

485
9. Ingrasys - Taoyuan, Taiwan Plant - Industrial Engineering 4.0 - WEF - McKinsey Light House Plant

By deploying AI use cases across order forecasting, warehouse and production scheduling, product design, quality and assembly-testing domains, Foxconn Industrial Internet’s Taiwan factory has achieved a 73% increase in production efficiency, a 97% reduction in product defects, a 21% reduction in lead time and a 39% decrease in unit manufacturing costs.


486
10. Johnson & Johnson - Industrial Engineering - Productivity Improvement Activities - Industry 4.0 Lighthouse Plant

Johnson Xi’an replaced its manual facility with a Fourth Industrial Revolution-enabled new factory in 2019. This facility includes digital twins for technology transfer and material handling, intelligent automation of continued process verification (CPV) and batch execution processes. 

This has shortened the product transfer time by 64% during site relocation and has enabled a 60% decrease in non-conformance, while improving productivity by 40%, operating costs by 24% and GHG emissions by 26%.


487
11. K-Water - Hwaseong - REPUBLIC OF KOREA - Industrial Engineering 4.0 - WEF - McKinsey Light House Plant

K-water launched a next-generation AI water treatment plant to reduce production costs, improve responsiveness and reduce human error. It is being scaled across 40+ other sites.

It has helped K-water to reduce its chemical usage by 19%, improve labour efficiency by 42% and reduce power consumption by 10%.

488
12. LONGi Solar - Jiaxing Plant - Industrial Engineering 4.0 - WEF - McKinsey Light House Plant

Jiaxing site implemented more than 30 Fourth Industrial Revolution use cases, using AI and advanced analytics to boost manufacturing operations. 

The site achieved a 28% reduction in unit manufacturing costs, a 43% cut in yield loss and an 84% decrease in production lead time within one year, while also lowering energy consumption by 20%.

489
13. Mondelēz - Beijing Plant - Industrial Engineering 4.0 - WEF - McKinsey Light House Plant
Mondelez - Sricity

Mondelēz Beijing implemented 38 Fourth Industrial Revolution use cases, such as an AI-powered dough-making lights-off workshop and gas consumption optimization by machine learning. As a result, Mondelēz Beijing has achieved a 28% net revenue growth and 53% increase in labour productivity while reducing GHG emissions by 24% and food waste by 29%.


490
14. Novo Nordisk - Hillerød Plant - Industrial Engineering 4.0 - WEF - McKinsey Light House Plant

Novo Nordisk has invested in digitalization, automation and advanced analytics, building a robust Industrial Internet of Things operating system to be scaled across their manufacturing footprint, increasing equipment efficiency and productivity by 30%.

491
16. Procter & Gamble - Takasaki Plant - Industrial Engineering 4.0 - WEF - McKinsey Light House Plant

The site implemented Fourth Industrial Revolution use cases such as data flow integration, digital twin, machine learning across end-to-end value chain (from R&D to customers). 

As a a result, the innovation lead time accelerated by 72%, shutdown days for trial were reduced by 21%, and order horizon from customers improved 14-fold.

The plant leverages 4IR capabilities such as data science, AI and machine learning across end-to-end value chain from R&D to retail customers. Altogether, it has been improving productivity and enabling faster reaction to market needs while growing production capability.


492
17. Quaker Houghton - Industrial Engineering 4.0 - Intelligent Die Casting

493
19. S   Schneider Electric - Hyderabad

Over four years, the plant reduced its energy consumption by 59 per cent, improved waste optimisation by 64 per cent, decreased CO2 emissions by 61 per cent, and reduced water consumption by 57 per cent.

To improve energy efficiency and thereby reduce CO2 emissions, the Hyderabad team focused on the highest energy consumers in the plant: air compressors and chillers. An IoT-enabled device, Equaliser 4.0, was installed to regulate the compressors, thereby improving their efficiency. For the chillers, a data-driven energy management system with closed-loop control was fitted to constantly monitor and adjust energy consumption in real-time, optimising energy efficiency.

494
20. T  The Coca-Cola Company - Ballina

The site implemented digital, and analytics use cases. As a result, it improved cost by 16% while expanding its SKU portfolio by 30%

495
21. U  Unilever - Sonepat

Unilever Sonepat implemented 30+ Fourth Industrial Revolution use cases in its E2E supply chain. Top use cases included boiler and spray dryer process twins, as well as customer data-informed no-touch production planning and inventory optimization. 

This improved service by 18%, forecast accuracy by 53%, conversion cost by 40% and Scope 1 carbon footprint by 88%.

496
23. W   Western Digital - Bang Pa-In

497
26. Z   Zymergen - Emeryville

Biotechnology firm Zymergen brought robotics and artificial intelligence (AI) to bioengineering labs, traditionally highly manual sites. 

Innovation rates soared, allowing Zymergen to use bioengineering for products previously were not feasible.



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498
Course End Summary - Part 1 - IEKC IE Online Course - Engineering in Industrial Engineering

499
Course End Summary - Part 2 - IEKC IE Online Course - Support from Non-Engineering Subjects



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1. Additive Manufacturing Productivity


Assembly Design Framework for Additive Manufacturing Based on Axiomatic Design Concept
https://www.xcdsystem.com/iise/abstract/File7673/UploadFinalPaper_2655.pdf
Yosep Oh, University at Buffalo; Sara Behdad, University at Buffalo, SUNY

Abstract:

AM productivity

According to the design for assembly (DFA) concept, design features should be integrated into a few physical parts to reduce design complexity.  However, building up a single product can have some negative effects on the AM productivity by increasing buildup time and cost. In this paper, a design framework using the assembly concept is proposed with the aim of letting the AM productivity reach an allowable level. The design framework is developed based on an Axiomatic Design (AD) approach, where AM productivity elements including buildup time, assembly time and the amount of support are considered as non-functional requirements (nFRs). The AM productivity is assessed by the Information Axiom to choose the best design. The proposed design framework can help engineers design and evaluate AM products.

Interesting references cited in the paper

* Thomas, D.S. and Gilbert, S.W., 2014, Costs and Cost Effectiveness of Additive Manufacturing - A Literature Review and Discussion, NIST.
* Oh, Y. and Behdad, S., 2016, Assembly Based Part Design to Improve the Additive Manufacturing
Productivity: Process Time, Cost and Surface Roughness, ASME IDETC, Charlotte, NC, USA.
* Zhang, Y., Bernard, A., Gupta, R.K. and Harik, R., 2014, Evaluating the Design for Additive Manufacturing: A Process Planning Perspective, Procedia CIRP, 21, 144–150.
* Thompson, M.K., 2013, Improving the Requirements Process in Axiomatic Design Theory, CIRP Annals - Manufacturing Technology, 62, 115–118.


2. Biomanufacturing (Biotechnology) Productivity

Productivity in Biomanufacturing

Researchers are examining the possibility of taking  advantage of the natural differences in productivity among cells that are used in biomanufacturing. They foster mutations to create genetic variability and then use microchips to analyze the behavior of individual cells, choosing the most prolific for larger-scale production.

https://www.technologyreview.com/s/424695/why-is-biomanufacturing-so-hard/
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3. Productivity and Nanotech

Productive Nanotech Systems
https://www.foresight.org/roadmaps/Nanotech_Roadmap_2007_main.pdf

Related

OSRAM Boosts LED Chip Productivity With Nanotechnology
Aug 27, 2014
https://www.nanowerk.com/nanotechnology-news/newsid=37099.php

4. Electric Batteries and Productivity Applications


Productivity and Industrial Engineering (IE) in Battery Manufacturing
https://nraoiekc.blogspot.com/2014/02/productivity-and-ie-in-battery.html

Nano One Enhances Pilot Productivity and Files a New Patent

Vancouver B.C. Dr. Stephen Campbell, Principal Scientist at Nano One Materials, today announced that Nano One has filed a patent related to yield improvements in its process for the manufacture of lithium metal oxide cathode materials for use in advanced lithium ion batteries.
August 2017

https://nanoone.ca/nano-one-enhances-pilot-productivity-files-new-patent/
---------

5. IoT and Productivity

McKinsey Global Institute Report
THE INTERNET OF THINGS: MAPPING THE VALUE BEYOND THE HYPE
JUNE 2015
You can donwload the report from the web
(Link)


How the Internet of Things will reshape future production systems
By Vineet Gupta and Rainer Ulrich
September 2017
https://www.mckinsey.com/business-functions/operations/our-insights/how-the-internet-of-things-will-reshape-future-production-systems


6. New Technology and Equipment for Productivity

PONSSE INTRODUCES NEW TECHNOLOGY FOR PRODUCTIVITY AND ERGONOMICS
Virtual reality (VR) training simulator.
http://www.ponsse.com/fr/media-archive/nouvelles/ponsse-introduces-new-technology-for-productivity-and-ergonomics

How Does Technology Affect Productivity?
Apr 9, 2014

 AIM's March 2014 Business Confidence Survey asked two questions.
1. "Has technology allowed your company to produce more goods or provide more services than a decade ago with the same or fewer employees?
2. Can you quantify the economic effect?"


62 percent of the employers who responded said "yes" to the first question.

Among them only some could quantify the benefits. The gains reported in productivity were in  the 10-25 percent range. At the limits,  one manufacturer doubled output without adding workers, and a non-profit service provider more than tripled productivity.

Regarding profit improvement, some manufacturers remarked  that productivity improvements did not strengthen their bottom lines due to downward pressure on prices.  Some  companies in services industries cited offsetting costs from new regulations.
https://blog.aimnet.org/AIM-IssueConnect/bid/103010/How-Does-Technology-Affect-Productivity

Trend 5: Technology enables greater productivity in infrastructure industry
https://home.kpmg.com/xx/en/home/insights/2017/01/trend-5-technology-increases-productivity-risk.html
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7. Productivity in Hotels

New JW Marriott hotel rides on technology for productivity
25 March 2017

The 634-room luxury hotel has "taken the initiative to implement new technologies and processes to improve the efficiency of its operations, as well as the overall guest experience" One of the systems  is the (hotel's) use of the Knowledge Touch rostering system to better manage and allocate manpower during peak periods by analysing business volume and needs. the hotel has also adopted Radio Frequency Identification (RFID) technology to track and replace worn-out items such as linen in hotel rooms and  has freed up valuable manpower for more productive uses .
http://www.asiahoreca.com/news/1164711/new-jw-marriott-hotel-rides-on-technology-for-productivity

JW Marriott Resort Saves $100K with Push-to-Talk Tech
12/09/2010
https://hospitalitytech.com/jw-marriott-resort-saves-100k-push-talk-tech


8. Industrial Engineering with New Materials
Engineering Materials for Cost Reduction
https://www.imetllc.com/engineering-materials-for-cost-reduction/

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9. Smart Manufacturing for Electronics Products
https://www.plm.automation.siemens.com/media/global/it/Siemens-PLM-Smart-manufacturing-for-electronics-wp_tcm56-57766.pdf

10. Inspection in the age of smart manufacturing
Tom Austin-Morgan, 05 November 2018
http://www.eurekamagazine.co.uk/design-engineering-features/technology/inspection-in-the-age-of-smart-manufacturing/192747/

Related
Smart Inspection Systems: Techniques and Applications of Intelligent Vision
Duc T. Pham, R J Alcock
Elsevier, 09-Dec-2002 - Technology & Engineering - 240 pages
https://books.google.co.in/books?id=i7EMwG0Cqk4C


Ud. 31.12.2024,  16..5.2024,  10.4.2023, 24.5.2022, 5.5.2022,  22.4.2022,  9.3.2022
Pub 30.5.2021
Posted by at 8 comments:
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Monday, December 30, 2024

Effort Rating or Pace Rating in Stop Watch Time Study

Effort Rating or Pace Rating Standard in Stop Watch Time Study. 3 miles per hour. Do you agree.

How many repetitions with 3 kg dumbbells can be done in 8 hours?


Doubt - Is 3 Miles per Hour Work Pace Standard Validated?


 Is Walking a Full Marathon in Eight Hours and  Fifteen minutes  the Work Standard as per Work Measurement

The standard pace for working is taken as 3 miles per hour or 5 km per hour in work measurement.

The above pace means that a worker can walk a full marathon every day comfortably. How many walk a full marathon even once in a year? Is this 3 mph standard validated scientifically by work measurement engineers?


Opinions and Statements by Writers on Work Measurement



Standard Pace

Presgrave thought the speed of motion of a man walking at 3 miles per hour on a level area or a man dealing a deck of cards into four equal piles in a half minute might be considered as representative of the normal speed. The speed of motions observed during these operations would be considered to be the standard for all operations. To make this representation more positive (and uniform), motion pictures would be made of an operator performing the specified operation. The film then becomes the constant yardstick from which reference can be made frequently or as desired.   Nadler commented that, this yardstick is like a meter definition. The yardstick defined by Presgrave is only like a measuring device. The yardstick itself was not standardized.

Nadler commented that within the limits of present knowledge, the concepts of this system up to this point represent the best practical answers.[1]

Presgrave [2] in chapter 13 discussed the appropriateness of taking  walking at three miles per hour speed as the standard for time study purposes. He also mentioned the standard of dealing a pack of card in 0.5 minutes.

Eskilson [3] came out with an equation that related the distance moved and the time taken with the acceleration.
D = (1/2)(a) (0.27T)2 + a(0.49T)(0.49T) + (1/2)(a) (0.27T)2

Barnes suggested that to demonstrate rating inside a company, some simple operations from the company or plant which can be performed by anyone should be selected. They must be standardized and the time for doing those jobs at normal pace has to be established ( 3 miles per hour walking is used as the standard yardstick). Then motion pictures are made of various operators and the tempo in percent of normal should be established. These films are to be shown to time study analysts as well as to others. By getting trained with these films even operators can do the rating apart from the time study analyst. (Page 300)

Interesting content on pace rating by ergonomists
Gregory Bedny, Waldemar Karwowski, Inna Bedny


A Survey of Performance Rating Research in Work Measurement
1988 MS Thesis, Kansas State University
http://ia601205.us.archive.org/35/items/surveyofperforma00devo/surveyofperforma00devo.pdf

https://archive.org/stream/surveyofperforma00devo/surveyofperforma00devo_djvu.txt

Original Knol - http://knol.google.com/k/narayana-rao/effort-rating-or-pace-rating-in-stop/ 2utb2lsm2k7a/ 3907


Ud. 30.12.2024, 22.3.2022, 25.1.2022,  8.1.2022
Pub 19.4.2012
Posted by at No comments:
Labels: ,

Sunday, December 29, 2024

Machines - Equipment Selection - Facilities Industrial Engineering

 

Open Access

Multi-Criteria Decision-Making for Machine Selection in Manufacturing and Construction: Recent Trends

by Asmaa M. Hagag , Laila S. Yousef  and Tamer F. Abdelmaguid.

Mathematics 2023, 11(3), 631; https://doi.org/10.3390/math11030631

https://www.mdpi.com/2227-7390/11/3/631


MCDM Methods for Selection of Handling Equipment in Logistics: A Brief Review

Alma Jusufbašić

 Vol. 1 No. 1 (2023): Spectrum of Engineering and Management Sciences

https://www.sems-journal.org/index.php/sems/article/view/2


To be summarized.

https://www.csemag.com/articles/14-aspects-to-consider-in-equipment-selection/


14 aspects to consider in equipment selection

Mechanical engineers should consider these key aspects when specifying systems for a building owner.

BY SETH PEARCE, PE, SOUTHLAND ENERGY, GARDEN GROVE, CALIF. APRIL 18, 2016


Equipment selection for a mechanical engineer is as much an art of application as a science of technology. Today, refinements to manufacturing, increasingly advanced controls, and changing end-user needs determine both the science of technology and the roster of equipment for selection. ) Over the past 15 years, a strong increase in customer needs  such as risk, aesthetics, longevity, maintenance, and efficiency, have added complexity to the determinants that need to be evaluated in equipment selection.


Demystifying the “wants” and “needs”


 The typical pattern involves building owners and/or end users simply expressing their “wants,” from robust to redundant to inexpensive. Difficulty can arise when these wants are discussed and prioritized against the needs identified to drive evaluation aspects. Core aspects exist that often are purely technical variables that require evaluation and satisfaction. Regardless, the subjective or intangible wants should not be ignored because of difficulties in quantifying the value. Instead, they should be distilled into needs and evaluated as key aspects in equipment selection.

Owners typically desire brand names and advanced equipment that will integrate into their building system, but they want it to be inexpensive to buy and operate and easy to replace. Brand equity is not so much a need as it is a method of ensuring a reputable warranty, parts availability, proven application, and a wide field of technicians able to service the equipment. 

While inexpensive is a want, the first cost or perhaps total cost of ownership is the need. For example, heat pumps are not very expensive to buy and install, but they do require invasive and time-consuming maintenance (versus a fan coil or variable air volume box); and they become loud and clunky over time. So would noise criterion levels or minimal interruption of the benefitted space trump costs? Not absolutely, but relatively to a point. Those needs must be emphasized and prioritized as necessary for evaluation in equipment selection.

Creating the roadmap for equipment evaluation

The best roadmap is the lifecycle cost analysis (LCCA) approach and its sum total of satisfying aspects. A total cost-of-ownership approach that identifies needs and assigns values to be evaluated can balance the limitations of first-cost considerations on total comfort, satisfaction, and long-term costs. To perform this, engineers must be able to specify the best equipment for a design as well as be subject matter experts on constructibility, operations, maintenance, human behavior, economics, and manufacturing. One challenge is identifying aspects for consideration. This diverse knowledge is necessary to create the roadmap for equipment evaluation.

The single greatest pressure on any evaluation is typically cost, and more commonly first cost. The first cost is comprised of the capital costs to design, furnish, and install a specific piece of equipment, and it is affected by project speed. Engineers are the subject matter experts that select based on the criterion to be evaluated, not only first cost.

In many instances, an owner structures and selects engineering firms, architects, and contractors to satisfy first cost. Therefore, there is no better arbitrator than the engineer to educate, evaluate, and recommend the selection of equipment that considers all aspects rather than only first cost. The engineer must have a good grasp of these aspects for equipment selection in the factors of their evaluation.


Factors of evaluation

A multitude of varying factors exist for every project and owner, including but not limited to:

First cost: Budgets are a strong consideration, and engineers must limit the equipment options to meet first-cost requirements. The total cost of installation including time, material, infrastructure, and opportunity costs must be evaluated.

Suitability: Equipment selection must be suitable to the application and building. For example, variable refrigerant flow or chilled beams are technologies that either do or do not work well. An example of unsuitability is chilled water in a data center. It is efficient at moving heat, but the presence of water (even with containment) is a risk that must be evaluated.

Constructability due to schedule, lead time, start-up/commission-ability: Aspects such as equipment procurement or tradesman installation time must be evaluated. For example, a piece of equipment that requires a highway shutdown so it can be transferred to the site will have an impact, as will the job site if the equipment must be moved via crane into place. Also, consider whether a piece of equipment can reside in the factory for an extra week if the construction schedule is unexpectedly impacted. Additionally, once the project is launched and commissioned, can the equipment sit unoccupied and not used for 3 months before occupancy?

Ease and cost of operations and maintenance: Do the evaluated equipment-selection aspects account for how preventive maintenance technicians will access the equipment? How accessible are the filters? Does special attention need to be placed on the design of the strainer locations? If the reversing valve fails in year eight, how dire will the beneficial space be to replace it? Are the economizer/outside-air dampers easy to access for maintenance?

Total cost of ownership: This entails first cost and all other major fixed and variable costs associated with the lifetime of the equipment evaluated at net-present value (NPV) against alternatives for selection. This aspect allows engineers to look at incremental factors, such as the benefit of variable frequency drives (VFDs) on the condenser water pumps or whether 1/10 less kW/ton material affects the NPV versus alternatives.

Experience and reputation of the equipment manufacturer: This aspect examines the potential of sourcing partners for equipment. Engineers, owners, and contractors have preferred partners. These manufacturers have gained favor through positive experiences. An engineer must understand the needs and be wary of marketing or prejudiced specifications.

Impact on other building design elements (size, location, interference): Engineers refer to this as coordination, or developing a method of evaluating the coordination with mechanical, electrical, plumbing (MEP), and other system design and installation. Engineers evaluate the risk of change orders, time delays, and other impacts in equipment selection that must be foreseen. For example, the contractor may have to reroute or core a hole in the floor because elevator hydraulic lines are already in the proposed path for the chilled-water supply and return.

Noise criteria (NC): This is a key aspect to be evaluated. Different scales for different frequencies of noise should be understood and evaluated, especially if equipment starts and stops routinely. Engineers must understand ambient noise, and come in under recommended or specified NC targets.

Lifespan: The average age of commercial or school buildings is slightly more than 40 years. Mechanical systems with proper maintenance can last more than 20 years, and others even longer Evaluating the requisite lifespan is an important aspect of equipment selection. A chiller can easily provide service for 15 years, while cooling tower life varies. A new programmable thermostat may need to be replaced in 8 years due to persistent button pushing. Realistic evaluation is important to achieve the project needs and secure return on investment; it affects total cost of ownership assumptions greatly.

Energy benefits (code requirements, energy efficiency, or value of the property): These types of evaluation variables are abstract and can be difficult to quantify, albeit not to be over-looked. A curious example exists in the Bank of America Tower in New York City, which is a notoriously energy-consumptive building despite having achieved the highest U.S. Green Building Council LEED certification available. Still, the building attracts major environmental-advocating tenets, demonstrating the value of its purported energy benefits.

Scalability, staging, and modularity of equipment: This involves aspects of future planning and optimum use. A cooling unit that runs near full load reaches peak efficiencies and likely achieves good investment economy of scale. However, the same unit that runs at part load does less so. And a unit that short-cycles may not be ideally efficient or cost-effective, but necessary. For projects with phased development and occupancy, perhaps evaluate for what is needed soon and consider scaling. For owner projects with wildly varying load requirements, consider evaluating the equipment needs to satisfy only 85% of those needs. For projects such as data centers with abrupt and rapid expansion needs, consider evaluating what equipment will work over time with the equipment selected now, and vice versa.

Redundancy and failure-node risk: Evaluate areas where weakest-link scenarios arise. There may be value in robust equipment in areas where a failure could lead to difficulties in the facilities. For example, valves, chillers, and pumps associated with a large thermal-energy storage system may require special consideration because the failure of any point therein could result in a facility unable to meet cooling requirements early the next afternoon.

Environmental health attributes : These evaluation criteria should be evaluated with owners, factory reps, and other authorities having jurisdiction (AHJ) requirements. For example, R-123 refrigerant has been a phenomenal performer through a wide range of compressor load levels, but it is unfavorable by some who cite its potential damage to the environment if leaked. Contrary, ammonia refrigerant is specialized and deadly, but favored by a few for its unique properties and relative friendliness to the environment.

Safety: This is an area every engineer must consider in equipment selection. What is safe to construct, operate, and maintain must be evaluated. For example, discussions with owners and contractors over what and where with regard to safety concerns can integrate project delivery and increase health and safety.

Every project is different, and equipment-selection aspects for evaluation must be specifically developed to meet each project’s unique needs and complexity. The main factors for evaluation can vary from a half dozen to hundreds. An engineer working on equipment selection can methodically develop that criterion and evaluate it to provide optimum choices.


Calculation of factors

Once identified from the project needs, key aspects an engineer should evaluate in equipment selection can be summarized in the simple math of weighted scoring, then mapped to money in LCCA, and reinforced for posterity in logic statements. The process assigns reasonable quantities to be evaluated to the variety of aspects. This transforms subjective qualities of a project’s needs to numerical analysis, considered the “art” of the process. An engineer can consider abstract wants and distill those into concrete needs, which are prioritized with weighting and used in a scorecard for equipment selection.

An example can be illustrated in three owner “wants”: a cutting-edge working environment, budget conformity, and reasonable operating costs. This could be described as cool, quiet, unobtrusive, inexpensive, efficient, and low-maintenance; or three wants summarized in six needs. Of those, five are subjective and one is objective because inexpensive typically correlates to a number. Once prioritized, these rank as inexpensive, cool, quiet, efficient, low-maintenance, and unobtrusive. In selection, engineers must find the least expensive equipment that will be cool and quiet enough; but once satisfied, every additional dollar for extra cooling or added quiet is a luxury. However, additional benefits in efficiency and low maintenance, even at the expense of low cost, can be evaluated to find an ideal cost/benefit ratio. After that, degrees of obtrusive can be weighed at the expense of the other needs and a final selection can be made. In the real world, there will be another half dozen purely technical requirements included in the selection, but the point can be seen: methodically eat this elephant, one bite at a time.

The biggest difficulty in evaluating so many characteristics in complex projects is the overwhelming degrees of freedom. Linear algebra offers advanced means to reconcile huge interrelated equations, but equipment selection is best served by a simpler routine. The design engineer should identify as many aspects that should be evaluated as possible, but only evaluate a dozen or fewer factors in equipment selection. Reviewing the big list frequently while limiting the number of parties involved provides good perspective on overall priorities, and many synergetic criteria are actually met by coincidence. Reviewing a significant list of evaluation criteria also enhances creative thinking and ensures selected equipment does not have a fatal failure for critical considerations not reviewed in a purely limited evaluation.

The limited aspects chosen for evaluation in equipment selection can be applied to different design options, or simply different brand names of equipment. Simple weighted scoring can potentially identify ideal equipment, and a LCCA can validate or re-evaluate that potential. Choose a realistic discount rate, relative to the owner’s approximate return on investment or cost of money. Select realistic escalation rates for energy, labor, or equipment. Assign annual occurrences, such as large overhauls or other anticipated repairs or replacements. The net-present or net-future values from a LCCA will ensure the total costs associated with a particular equipment selection have been considered. Comparing alternative LCCAs for different potential equipment pieces is fast and routine, but the output is very telling.

Once a conclusion is reached on a particular equipment selection, document a summary of the evaluation, the peer contenders, and three reasons the selected equipment was chosen. In circumstances where others will be procuring, if options between equipment choices will still be made, it is important to rank two to five of the highest evaluated equipment, with short comments why.


The key aspects that mechanical engineers need to consider in equipment selection are nuanced. It can be as simple or complex as necessary, but regardless, it must be comprehensive. An excellent understanding of owners’ wants is required, in combination with a good network of experience and peers to draw upon, and a methodological system of scoring and evaluation. It requires an engineer to communicate efficiently and reinforce conclusions, and should result in ongoing collaboration with the owner to ensure desired attributes are captured. Both the right and left brain will be activated to achieve both the art and science of evaluating abstract conditions and technical applications. It requires financial sensitivity and analysis. Most of all, a good foundation in engineering is needed, along with common sense and the ability to understand how important these nuanced selections are to achieve many years of comfort, safety, and performance.


Seth Pearce is director of design and development for Southland Energy, a division of Southland Industries. In this role, he helps to de­velop and implement solutions to conserve energy, waste, and water; integrate gener­ation; and incorporate renewable energy.


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https://machinethug.com/factor-affecting-selection-of-construction-equipment/





Factor Affecting Selection of Construction Equipment

BLOG / BY SUNDERVEER RAJPUT

Construction equipment or Heavy Equipment selection is difficult just because of the main only reason costing of the machine. A small amount of investment does not require much attention. While you are doing investment with the bigger amount you need to focus on that investment in need to check all angles of that. The advantages and disadvantages of equipment will clear you what exactly steps you need to take.


We will point out all factors which really matter your decision making in the purchase decision.


Table of Contents

1. Requirement of Equipment

2. Operating Cost of Equipment

3. Owning Cost

4. Suitable for Construction Project

5. Labour Consideration

6. Selection of Machinery

7. Brand and Model

8. Availability of Spare Parts

9. Economic life of Construction Equipment

10. Unit Cost of Production

1. Requirement of Equipment

Really you required that equipment or you can get it done your work without that equipment also because many time company or individual do the investment that not even necessary. It commonly happens that for certain single work you buy that equipment due to the nonavailability of equipment in the market on a rental basis. So be sure that without that machine can you get done your work.   


2. Operating Cost of Equipment

Before you make a decision check the operating cost of equipment. Elephant feeding cost is higher than the buying cost. If the Operating cost of the machine higher than the investment please check the ROI.


Operating Cost includes transportation, labour costs, Electricity Cost, Fuel Consumption, Operator cost need to check in excel what is per month, or yearly costing. Do you get the real benefit of what you are looking for?


3. Owning Cost

Owning cost is different than the operating cost. Owning costs consider buying costs. An investment made on the purchase of machinery. Owing cost includes the EMI Costing, Financier yearly fees, purchase price. You need to check both costing operating + owning. Does both these cost allow you to buy machinery?


4. Suitable for Construction Project

Does your investment suitable to project for what you are making an investment. The wrong decision puts you in the problem. As you require the EOT crane but made the decision buy of a tower crane. A wrong decision will make more costing or even not fulfill your requirement. So be sure if don’t have technical knowledge then take the help of consultancy they will help you out to make the right decision.


Don’t take advice from manufacturer sales guys they always guide you in which they have more profit. Try to take help from where you get unbiased help.


5. Labour Consideration

Does your investment impact on labour? If so take decision wisely calculate the investment costing against the labour costing. Check the Union reaction also it might happen that one machine investment lay off all the labour from the company. So the decision should be such that everyone happy and even its favour to the company also.


6. Selection of Machinery

The selection of machinery is another factor needs to check very seriously. The machine should be advanced technology-enabled. Give you more productive results at minimum operating costs. Machinery manufacturer dealers or service persons should near you so that the anytime service need can be fulfilled. Maintenance costs should be lower as compared to other competitive machinery manufacturers. Compare the financial benefits of the manufacturer who give you more benefits in terms of advance and credit.  


7. Brand and Model

 Select brand and model that is most demanded in the market because if in future if you need to rent it out so you get the good rental income from your heavy equipment. Out of the many models and brands take care of the resale value also of equipment. Is there any policy of buyback from the manufacturer if not then ask to have it before finalizing the equipment. Compare the model of 2 or more brands with the same capacity as Hitachi Ex 210 & Komatsu PC210.


8. Availability of Spare Parts

Do spare parts are easily available for your constriction equipment? If spare parts are not easily available in the market will cost you in the future and it can stop your working project site and impact on your income. The single seal of a cylinder can stop your whole project site work.  


9. Economic life of Construction Equipment

The economic life of the machine will give you recover the cost as per the financial as well as the market value. Be clear with economic life until when the machine gives you income and also consider the resale value of the machine.    


10. Unit Cost of Production

Be clear with a unit cost of production so you have an idea what charges you should ask when you have a contract per cubic based project. Project-based work give more benefit as compare to rental base. Before you buy any of the equipment ask for sale a person per hour maintenance cost of equipment. Like JCB operating cost per hour is 42 rupees. The same all other equipment has its own unit cost of production.


Whether construction equipment or any other equipment factor affecting selection of construction equipment processes will more or less the same. So clear with all points if doubt on someone please ask in below comment box.  


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Time Study for Machines - Machine Time Estimation - Actual Measurement - Improvement

 

TIME STUDY AS A METHOD FOR MEASURING MACHINERY PERFORMANCE

By T. J. MURRAY and E. MEYER

South African Sugar Association Experiment Statiqn, Mount Edgecombe 4300

Proceedings of The South African Sugar Technologists' Association -June 1982

https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=dbcd6083039806b5b89465c298aaa00de6909726



Time study is a method of measuring work done by man and machine. Time study can be used to establish machinery performance standards and to measure actual productivity for comparison with pre-determined standards. 


https://jingxinwang.forestry.wvu.edu/files/d/e3e83f21-f011-4916-9b39-e1af07a30de6/production2.pdf

Elemental Time Studies • Elemental time studies record times for machine activities:– from continuous observation of the machine – for a longer period of time • Machine time is divided into elements.


• Each element: – has clearly recognizable starting and ending points– allows consistent timing in the field




Very Interesting


Time Study Standards

STANDARDS FOR TIME STUDIES FOR THE SOUTH AFRICAN FOREST INDUSTRY



5.0 Machine Element Standardisation

5.1 Standardised Element Lists by Machine

5.1.1 Harvesting Machines:

Chainsaw:

Harvester:

Feller-buncher:

Skidder/agricultural tractor with winch or drawbar (a-frame or other):

Skidder (grapple):

Forwarder:

Loader (either tracked or wheeled):

Processor:

Truck (timber transport):

Yarder:

Mulchers and Destumpers:

5.1.2 Silviculture Machines:

Auger, mechanical:

Clearing saw, mechanical:

Disc, tractor drawn:

Mulcher, self-propelled or tractor-drawn:

Planter, tractor-drawn or machine mounted:

Pitting machine, Multi-pit:

Pitting machine, Single-pit:

Pruner:

Sprayer, tractor drawn or machine mounted

Stump removing saw, self-propelled:


https://www.forestproductivity.co.za/document2/#5.0


The question and data missing - What are the machine speeds possible? What is the machine speed used?










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Work Measurement - Nadler's Description



Gerald Nadler described the process of work measurement under the following chapters.

20. Concepts and Problems of Standards Setting
21. Recording Conditions and Method
22. Timing
23. Pace Comparison
24. Difficulty comparison
25. Allowances
26. Standard Data
27. Applying and Controlling Standards

Industrial Need for Standards

1. Balance of work
2. Equipment Requirements
3. Manpower Requirements
4. Production Planning
5. Cost Planning
6. Production Control
7. Cost Control
8. Wage Incentives

What is Standards Setting?

Standards setting techniques determine the time an operation or element of an operation, performed with a given method under given job conditions, should take; when worked on by an operator with the necessary skill and given sufficient training to perform the operation properly, working at the pace, maintainable througout the day, week etc., specified as equivalent to the work necessary to earn base pay; and when all the operator's required activity and needs are provided for. This amount of time is called the allowed or standard time.

Methods of Standard Setting

1. Time Study: Study of operation while it is being performed.
2. Standard Data: Determining standard for an operation by reference to information from earlier studies on similar jobs jobs having similar elements, collected and arranged properly.

Factors in Time Study

1. Given Method
2. Job Conditions
3. Time for Operation or Element

In a time study operation time is to be measured and along with it the pace of the operator and difficulty of of the operation are also to be measured.

Nadler comes out with a concept called Factor X which if it improves reduces the time required to do an element. All the items influencing Factor X can be summed up as the operator's psychological, physiological, and sociological relation to his environment and operation.

Recording Conditions and Method

Allowed time or standard time is associated with a given method.

The steps involved in recording conditions and method are:

1. Get permission of the foreman and cooperation of the operator
2. Observe the method
3. Record all conditions surrounding the operation
4. Make a rough breakdown of the operation - Regular occurrences and irregular occrrences
5. Break the work into elements
 a. Elements have therbligs as much alike as possible
 b. Have a definite end point
 c. Are  as short as possible, compatible with accuracy of the measuring instrument
      With a stop watch 0.03 to 0.04 minute can be measured.
      With motion films times up to 1/16 second  can be measured. But practically less than 0.01 minute are not used.
 d. Separate machine time and manual time
  e. Separate constant elements and variable elements
6. Detail each element
7. Put all information in final form

Timing

Timing techniques or Instruments

1. Electronic Devices
2. Motion pictures
3. Paper-tape recording machines
4. Stop watches
5. Sweep second wrist watch
6. Occurrence study (Work sampling)
7. Wall clock
8. Operator records time

The Timing Procedure

1. Check training record of the operators and select the operator
2. Check the method: To make sure operator is using the same method that is recorded in the recording step of the time study.
3. The analyst must have proper position to observe the end point of every element.
4. How many readings?
A graphical aid was given by Lehrer and Moder in Journal of Industrial Engineering, February 1953.
Mathematical treatment is also given by Nadler (pp. 370-378)
5. Timing machine controlled elements: Even though they can be calculated timing them is advised.
6. Record all occurrences, irregular elements, unexpected events etc.
7. Measure of central tendency for the element

Pace Comparison

After discussing measuring time, Nadler discusses measurement of Factor X. He said any of them can be discussed first. Time study is supposed to determine the amount of time an operation should take for any average operator. Hence, observation of any operator for determining the allowed time must be related in some way to a concept which will provide standard time. Factor X is conceptualized to have effect on observed time.

Two factors are to be evaluated in doing time study.

1. How is the operator's performance in comparison to performance other members of his group, or plant or operators in general?
2. How does the job being studied compare in terms of difficulty with other operations in the plant?

The answers to these two questions help adjusting the observed values to get standard value.

Does Factor X decrease with time? Nadler answers this question with no. Factor X does not decrease with time, but late in the day, operators take more timeouts is the answer of Nadler.

Factor X needs to be measured for each element. But it may not be possible unless element has a time measurement of 0.5 minute or higher.

Review of Factor X measuring techniques: Nadler presented a review of Factor X measuring techniques.
1. Over-all Evaluation
2. Good Performance
3. Mathematical or Statistical Manipulation of Time Data
4. Skill and Effort
5. Speed
6. Speed with 100 Per Cent Film
7. Speed Measurements with 100 Per Cent Step Film, Separated from Job Difficulty Measurements
8 Acceleration,Velocity, and Deceleration of Body Motions Measurements,with Universal Operator Performance Analyzer and Recorder (UNOPAR),Separated from Job Difficulty Measurements.

Nadler also discussed the issue of validating the pace measurements or Factor X measurements.


Source: Gerald Nadler, Motion and Time Study, McGraw-Hill Book Company, Inc, New York, 1955


Ud. 29,12,2024
Pub. 19.4.2012

Original Knol - http://knol.google.com/k/narayana-rao/work-measurement-nadler-s-description/ 2utb2lsm2k7a/ 2668
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Saturday, December 28, 2024

Work Measurement - ILO Work Study Book Explanation

Work measurement professionals have to focus on machine time estimation also. Also, they have to focus on developing productivity science based on measurements that they are taking.   My comment in work measurement Linkedin group.




The term "work measurement",  is  a term used to describe a family of techniques, any one of which can be used to measure work.

Work measurement is concerned with investigating, reducing and subsequently eliminating ineffective time, that is time during which no effective work is being performed, whatever the cause.

Work measurement, as the name suggests, provides management with a means of measuring the time taken in the performance of an operation or series of operations in such a way that ineffective time is shown up and can be separated from effective time. In this way its existence, nature and extent become known where previously they were concealed within the total.

One of the surprising things about plants where work measurement or any other waste elimination has not need been employed is the amount of ineffective time whose very existence is unsuspected — or which is accepted as "the usual thing" and something inevitable that no one can do much about — that is built into the process. Once the existence of ineffective time has been revealed and the reasons for it tracked down, steps can usually be taken to reduce it.

The above explanation of work measurement does not get emphasis in practice. 

Taylor's Time Study as it is popularly known is used for identifying the best way doing different elements of an job. It is more appropriate to term it "Process Time Reduction Study."

(F.W. Taylor's Time Study - 1912 - Taylor's Process Time Reduction Study
https://nraoiekc.blogspot.com/2019/09/fw-taylor-explanation-of-time-study-1912.html

Time Study - 1903 Explanation by F.W. Taylor - Process Time Reduction Study
https://nraoiekc.blogspot.com/2013/08/time-study-by-fw-taylor.html)

Work measurement has another role to play. It can  be used to set standard times for carrying out the work, so that, if any ineffective time does creep in later, it will immediately be shown up as an excess over the standard time and will thus be brought to the attention of management.

This role of work measurement to set standard time got all the emphasis in book by Barnes and also in the ILO Book. Readers have to note the shortcoming.

Method study reveals shortcomings of design, material, equipment, its accessories, cutting tools and method of manufacture, and, as such, affects mainly technical decisions.  Work measurement is more likely to show up short comings on the part of management  and the motions,  movements and idle time  of the workers.

On the basis of work measurement, the elimination of ineffective time due to management shortcomings must precede any attack on the ineffective time within the control of the workers.


Utility - Uses of  work measurement:


(1) To compare the efficiency of alternative methods. Other conditions being equal, the method which takes the least time will be the best method.
(2) To balance the work of members of teams, in association with multiple activity charts, so that, as nearly as possible, each member has a task taking an equal time to perform (gang process chart) .
(3) To determine, in association with worker and machine multiple activity charts, the number of machines an operative can run .

The time standards, once set, may then be used:
(4) To provide the basis for production planning and control for the choice of a better layout and for process planning, and for establishing just-in-time inventory control systems .
(5) To provide information that can enable estimates to be made for tenders, selling prices and delivery dates.
(6) To set standards of machine utilization and labour performance which can be used for any of the above purposes and as a basis for incentive schemes.

To use as basis for incentive schemes, the appropriate definition of work measurement is, "Work measurement is the application of techniques designed to establish the time for a qualified worker to carry out a task at a defined rate of working."

(7) To provide information for labour-cost control and to enable standard costs to be fixed and maintained.

The basic procedure

SELECT the work to be studied.

RECORD all the relevant data relating to the circumstances in which the work is being done, the methods and the elements of activity in them.

EXAMINE the recorded data and the detailed breakdown critically to ensure that the most effective method and motions are being used and that unproductive and foreign elements are separated from productive elements.

MEASURE the quantity of work involved in each element, in terms of time, using the appropriate work measurement technique.

COMPILE the standard time for the operation, which in the case of stop-watch time study will include time allowances to cover relaxation, personal needs, etc.

DEFINE precisely the series of activities and method of operation for which the time has been compiled and issue the time as standard for the activities and methods specified.

The techniques of work measurement

Principal techniques

  • time study;
  • structured estimating;
  • standard data.
  • predetermined time standards (PTS);
  • work sampling;



CHAPTER 21 Time study: Selecting and timing the job


1. Selecting the job

Some possible reasons for ding a time study are:

(1) The job  is a new one (new product, component, operation or set of activities).
(2) A change in material or method of working has been made and a new time standard is required.
(3) A complaint has been received  about the time standard for an operation.
(4) A particular operation appears to be a "bottleneck" holding up subsequent operations.
(5) Standard times are required before an incentive scheme is introduced.
(6) The output of an equipment is low, and it therefore becomes necessary to investigate the method of its use.
(7) The job needs studying as a preliminary to making a method study, or to compare the efficiency of two proposed methods.
(8) The cost of a particular job appears to be excessive.

If the purpose of the study is the setting of performance standards, it should not normally be undertaken until method study has been used to establish and define the most satisfactory way of doing the job.

A distinction is made in time study practice between what are termed representative workers and qualified workers. A representative worker is one whose skill and performance is the average of the group under consideration, and who is not necessarily a qualified worker. The concept of the qualified worker is an important one in time study. This person is defined as follows:

"A qualified worker is one who has acquired the skill, knowledge and other attributes to carry out the work in hand to satisfactory standards of quantity, quality and safety."

If a new method has been installed, the worker must be allowed plenty of time to settle down before timing starts. It takes quite a long time for an operative to adapt and to reach a maximum steady speed. Depending on the duration and intricacy of the operation, it may be necessary to allow a job to
run for days or even weeks before it is ready to be timed for the purpose of setting standards. In the same way, the work done by new operatives should never be used for timing until they have grown thoroughly accustomed to their jobs.

The study person's exact position will be determined by the type of operation being studied, but the position generally recommended is to one side of the operative, slightly to the rear and about 2 metres away.

The study board and watch should be held well up in line with the job, to make reading the watch and recording easy while maintaining continuous observation.

On no account should any attempt be made to time the operative without his or her knowledge, from a concealed position or with the watch in the pocket. It is dishonest and, in any case, someone is sure to see and the news will spread like wildfire. Work study should have nothing to hide.

Time study demands intense concentration and alertness, especially when timing very short "elements" or "cycles" (defined later in this chapter), and it is generally agreed that this is better attained when standing.

Steps in making a time study


When the work to be measured has been selected, the making of a time study usually consists of the following eight steps:

(1) Obtaining and recording all the information available about the job, the operative and the surrounding conditions, which is likely to affect the carrying out of the work.
(2) Recording a complete description of the method, breaking down the operation into "elements".
(3) Examining the detailed breakdown to ensure that the most effective method and motions are being used, and determining the sample size.
(4) Measuring with a timing device (usually a stop-watch) and recording the time taken by the operative to perform each "element" of the operation.
(5) At the same time, assessing the effective speed of working of the operative relative to the observer's concept of the rate corresponding to standard rating.
(6) Extending the observed times to "basic times".
(7) Determining the allowances to be made over and above the basic time for the operation.
(8) Determining the "standard time" for the operation.



Checking the Method


Before proceeding with the study, it is important to check the method being used by the operative. If the study is for the purpose of setting a time standard, a method study should already have been made and a written standard practice sheet completed. In this case it is simply a question of comparing what is actually being done with what is specified on the sheet. If the study is being made as the result of a complaint from workers that they are unable to attain the output set by a previous study, their methods must be very carefully compared with that used when the original study was made. It will often be found in such cases that the operatives are not carrying out the work as originally specified: they may be using different tools, a different machine setup or different speeds and feeds, temperatures, rates of flow or whatever the requirements of the process may be, or additional work may have crept in. It may be that the cutting tools are worn, or have been sharpened to incorrect profiles. Times obtained when observing work carried out with worn tools or incorrect process conditions should not be used for the compilation of time standards.

In highly repetitive short cycle work, such as work on a conveyor band (light assembly, packing biscuits, sorting tiles), changes in method may be much more difficult to detect, since they may involve changes in the movements of the arms and hands of the operative ("motion patterns") which can be observed only with difficulty by the naked eye and require special apparatus to analyse.


Breaking the job into elements


An element is a distinct part of a specified job selected for convenience of observation, measurement and analysis

A work cycle is the sequence of elements which are required to perform a job or yield a unit of production. The sequence may sometimes include occasional elements

A work cycle starts at the beginning of the first element of the operation or activity and continues to the same point in a repetition of the operation or activity. That is the start of the second cycle.

A detailed breakdown into elements is necessary:

(1) To ensure that productive work (or effective time) is separated from unproductive activity (or ineffective time).
(2) To permit the rate of working to be assessed more accurately than would be possible if the assessment were made over a complete cycle. The operative may not work at the same pace throughout the cycle, and may tend to perform some elements more quickly than others.
(3) To enable the different types of element (see below) to be identified and distinguished, so that each may be accorded the treatment appropriate to its type.
(4) To enable elements involving a high degree of fatigue to be isolated and to make the allocation of fatigue allowances more accurate.
(5) To facilitate checking the method so that the subsequent omission or insertion of elements may be detected quickly. This may become necessary if at a future date the time standard for the job is queried.
(6) To enable a detailed work specification to be produced.
(7) To enable time values for frequently recurring elements, such as the operation of machine controls or loading and unloading work pieces from fixtures, to be extracted and used in the compilation of standard data.


Types of elements 


Eight types of element are distinguished: repetitive, occasional, constant, variable, manual, machine, governing, and foreign elements. 


A repetitive element is an element which occurs in every work cycle of an operation.
Examples: the element of picking up a part prior to an assembly operation; the element of locating a workpiece in a holding device; putting aside a finished component or assembly.

An occasional element is an element which does not occur in every work cycle of an operation but which may occur at regular or irregular intervals.
Examples: adjusting the tension, or machine setting; receiving instructions from the supervisor. The occasional element is useful work and a part of the job. It will be incorporated in the final standard time for the job.

A constant element is an element for which the basic time remains constant whenever it is performed.
Examples: switch on machine; gauge diameter; screw on and tighten nut; insert a particular cutting tool into machine.

A variable element is an element for which the basic time varies in relation to some characteristics of the product, equipment or process, e.g. dimensions, weight, quality, etc.
Examples: saw logs with handsaw (time varies with hardness and diameter); sweep floor (varies with area); push trolley of parts to next shop (varies with distance).

A manual element is an element performed by a worker.

A machine element is an element performed automatically by any process, physical, chemical or otherwise that, once started, cannot be influenced by a worker except to terminate it prematurely.
Examples: anneal tubes, fire tiles; form glass bottles; press car body shell
to shape; most actual cutting elements on machine tools.

A governing element is an element occupying a longer time within a work cycle than that of any other element which is being performed concurrently.
Examples: turn diameter on a lathe, while gauging from time to time; boil kettle of water, while setting out teapot and cups; develop photographic negative, while agitating the solution occasionally.

A foreign element is an element observed which does not form a part of  the operation(s) being studied
Examples: in furniture manufacture, sanding the edge of a board before planing has been completed; degreasing a part that has still to be machined further.

It will be clear from the definitions given above that a repetitive element may also be a constant element, or a variable one. Similarly, a constant element may also be repetitive or occasional; an occasional element may be constant or variable, and so on, for the categories are not mutually exclusive.

Deciding on the elements


There are some general rules concerning the way in which a job should be broken down into elements. They include the following:

Elements should be easily identifiable, with definite beginnings and endings so that, once established, they can be repeatedly recognized. These beginnings and endings can often be recognized by a sound (e.g. the stopping of a machine, unlocking a catch of a jig, putting down a tool) or by a change of direction of hand or arm. They are known as the "break points" and should be clearly described on the study sheet. A break point is thus the instant at which one element in a work cycle ends and another begins.

Elements should be as short as can be conveniently timed by a trained observer. The smallest practical unit that can be timed with a stop-watch,  is generally considered to be about 0.04 min. (2.4 sec). For less highly trained observers it may be 0.07 to 0.10 min. Very short elements should, if possible, be next to longer elements for accurate timing and recording. Long manual elements should be rated about every 0.33 min. (20 sec).

As far as possible, elements — particularly manual ones — should be chosen so that they represent naturally unified and recognizably distinct segments of the operation. For example, consider the action of reaching for a wrench, moving it to the work and positioning it to tighten a nut. It is possible to identify the actions of reaching, grasping, moving to the work piece, shifting the wrench in the hand to the position giving the best grip for turning it, and positioning. The worker will probably perform all these as one natural set of motions rather than as a series of independent acts. It is better to treat the group as a whole, defining the element as "get wrench" or "get and position wrench" and to time the whole set of motions which make up the group, than to select a break point at, say, the
instant the fingers first touch the wrench, which would result in the natural group of motions being divided between two elements. 

Manual elements should be separated from machine elements. This may sometimes be difficult for short cycles. However, although manual and machine time may run concurrently it may be necessary to measure them separately to derive standard data. Machine time with automatic feeds or fixed speeds can be calculated and used as a check on the stop-watch data.

Hand time is normally completely within the control of the operative.

Constant elements should be separated from variable elements.

Elements which do not occur in every cycle (i.e. occasional and foreign elements) should be timed separately from those that do. The necessity for a fine breakdown of elements depends largely on the
type of manufacturing, the nature of the operation and the results desired.

Assembly operations in the light electrical and radio industries, for example, generally have short cycle operations with very short elements. The importance of the proper selection, definition and description of elements must again be emphasized. The amount of detail in the description will depend on a number of factors, for instance:

Small batch jobs which occur infrequently require less detailed element descriptions than long-running, high-output lines.

Movement from place to place generally requires less description than hand and arm movements.

Elements should be checked through a number of cycles and written down before timing begins.




CHAPTER 22

Time study: Rating


The procedures described in this chapter represent sound current practice.  They will certainly provide the reader with a sound basic system which will be suitable for most general applications, and one which can later be refined if the particular nature of certain special operations requires a modification of the system, so as to rate something other than effective speed.

In one study it was noted that it was only after some 8,000 cycles of practice that the times taken by workers began to approach a constant figure — which was itself half the time they took when they first tried the operation. Thus time standards set on the basis of the rate of working of inexperienced workers could turn out to be quite badly wrong, if the job is one with a long learning period. Some jobs, of course, can be learned very quickly.

Rating is the assessment of the worker's rate of working relative to the observer's concept of the rate corresponding to standard pace

Standard performance is the rate of output which qualified workers will naturally achieve without over-exertion as an average over the working day or shift, provided that they know and adhere to the specified method and provided that they are motivated to apply themselves to their work. This performance is denoted as 100 on the standard rating and performance scales

The rate of working most generally accepted in the United Kingdom and the United States as corresponding to the standard rating is equivalent to the speed of motion of the limbs of a man of average physique walking without a load in a straight line on level ground at a speed of 4 miles an hour (6.4 kilometres per hour). This is a brisk, business-like rate of walking, which a man of the right physique and well accustomed to walking might be expected to maintain, provided that he took appropriate rest pauses every so often. This pace has been selected, as a result of long experience, as providing a suitable benchmark to correspond to a rate of working which would enable the average qualified worker who is prepared to apply himself to his task to earn a fair bonus by working at that rate, without there being any risk of imposing on him any undue strain that would affect his health, even over a long period of time. (As a matter of interest, a man walking at 4 miles an hour (6.4 km/hr.) appears to be moving with some purpose or destination in mind: he is not sauntering, but on the other hand he is not hurrying. People hurrying, to catch a train for instance, often walk at a considerably faster pace before breaking out into a trot or a run, but it is a pace which they would not wish to keep up for very long.)


It should be noted, however, that the "standard pace" applies to Europeans and North Americans working in temperate conditions; it may not be a proper pace to consider standard in other parts of the world. In general, however, given workers of proper physique, adequately nourished, fully trained and suitably motivated, there seems little evidence to suggest that different standards for rates of working are needed in different localities, though the periods of time over which workers may be expected to average the standard pace will vary very widely with the environmental conditions. At the very least, the standard rate as described above provides a theoretical datum line with which comparisons of performance in different parts of the world could be made in order to determine whether any adjustment may be necessary. 

Another accepted example of working at the standard rate is dealing a pack of 52 playing cards in 0.375 minutes.


When time standards are used as a basis for payment by results, many union-management agreements stipulate that the time standards should be such that a representative or average qualified worker on incentive pay can earn 20-35 per cent above the time rate by achieving the standard performance. If these workers have no target to aim at and no incentive to make them desire a higher output, they will (apart from any time consciously wasted) tolerate the intrusion of small amounts of ineffective time, often seconds or fractions of seconds between and within elements of work. In this way they may easily reduce their performance over an hour or so to a level well below that of the standard performance. If, however, they are given enough incentive to make them want to increase their output, they will get rid of these small periods of ineffective time, and the gaps between their productive movements will narrow. This may also alter the pattern of their movements.

Judgement of walking pace is only used for training work study persons in the first stages; it bears very little resemblance to most of the jobs that have to be rated. It has been found better to use films or live demonstrations of industrial operations.

Confidence in the accuracy of one's rating can be acquired only through long experience and practice on many types of operation — and confidence is essential to a work study person.

The effective speed of the operation has to be rated. Ineffective movements are to be identified and removed. Judgement of effective speed can only be acquired through experience and knowledge of the operations being observed.

It is very easy for an inexperienced study person either to be fooled by a large number of rapid movements into believing that an operative is working at a high rate or to underestimate the rate of working of the skilled operative whose apparently slow movements are very economical of motion.

Should effort be rated, and if so, how? The problem arises as soon as it becomes necessary to study jobs other than very light work where little muscular effort is required. Effort is very difficult to rate. The result of exerting effort is usually only seen in the speed.

The amount of effort which has to be exerted and the difficulty encountered by the operative is a matter for the study person to judge in the light of experience with the type of job. For example, if an operative has to lift a heavy mould from the filling table, carry it across the working area and put it on the ground near the ladle, only experience will tell the observer whether the speed at which it is being done is normal, above normal or subnormal. Those who had never studied operations involving the carrying of heavy weights would have great difficulty in making an assessment the first time they saw such an operation.

Factors affecting the rate of working

Variations in actual times for a particular element may be due to factors outside or within the control of the worker. Those outside this control may be:


  • variations in the quality or other characteristics of the material used, although they may be within the prescribed tolerance limits;
  • changes in the operating efficiency of tools or equipment within their useful life;
  • minor and unavoidable changes in methods or conditions of operation;
  • variations in the mental attention necessary for the performance of certain of the elements;
  • changes in climatic and other surrounding conditions such as light, temperature, etc.


These can generally be accounted for by taking a sufficient number of studies to ensure that a representative sample of times is obtained.

Factors within the operative's control may be:


  • acceptable variations in the quality of the product;
  • variations due to the individual's ability;
  • variations due to the attitude of mind, especially the attitude to the organization for which he or she works.


The factors within the worker's control can affect the times of similarly described elements of work by affecting:

  • the pattern of the worker's movements;
  • the individual working pace;
  • both, in varying proportions.


The study person must therefore have a clear idea of the pattern of movement which a qualified worker should follow, and of how this pattern may be varied to meet the range of conditions which that worker may encounter. Highly repetitive work likely to run for long periods should have been studied in detail through the use of refined method study techniques, and the worker should have been suitably trained in the patterns of movement appropriate to each element.

The optimum pace at which the worker will work depends on:


  • the physical effort demanded by the work;
  • the care required on the part of the worker;
  • training and experience.


Greater physical effort will tend to slow up the pace. The ease with which the effort is made will also influence the pace. For example, an effort made in conditions where operatives cannot exert their strength in the most convenient way will be made much more slowly than one of the same magnitude in which they can exert their strength in a straightforward manner (for instance, pushing a car with one hand through the window on the steering-wheel, as opposed to pushing it from behind). Care must be taken to distinguish between slowing up due to effort and slowing up due to fatigue.


Scales of rating


There are several scales of rating in use, the most common of which are those designated the 60-80, 75-100 and 100-133 scales. The British Standard scale,  0-100 scale,  is  used in this book. It is  essentially a restatement of the 75-100 scale.

In the 60-80, 75-100 and 100-133 scales, the lower figure in each instance was defined as the rate of working of an operative on time rates of pay; and the higher, in each case one-third higher, corresponded to the rate of working we have called the standard rate, that of qualified workers who are suitably motivated to apply themselves to their work, as for instance by an incentive scheme. The underlying assumption was that workers on incentive perform, on average, about one-third more effectively than those who are not. This assumption has been well substantiated by practical experience over many years, but it is largely irrelevant in the construction of a rating scale. All the scales are linear. There is therefore no need to denote an intermediate point between zero and the figure chosen to represent the standard rating as we have defined it. Whichever scale is used, the final time standards derived should be equivalent, for the work itself does not change even though different scales are used to assess the rate at which it is being carried out.

The newer 0-100 scale has, however, certain important advantages which have led to its adoption as the British Standard. It is commended to readers of this book and is used in all the examples which follow. In the 0-100 scale, 0 represents zero activity and 100 the normal rate of working of the motivated qualified worker— that is, the standard rate.

Recording the rating


In general, each element of activity must be rated during its performance before the time is recorded, without regard to previous or succeeding elements.

In the case of very short elements and cycles this may be difficult. If the work is repetitive, every cycle or possibly the complete study may be rated. This is done when the short cycle study form  is used.

It is most important that the rating should be made while the element is in progress and that it should be noted before the time is taken, as otherwise there is a very great risk that previous times and ratings for the same element will influence the assessment. For this reason the "Rating" column on the time study sheet  is placed to the left of the "Watch reading" column. It is, perhaps, a further advantage of the cumulative method of timing that the element time does not appear as a separate figure until the subtractions have been made later in the office. If it did, it might influence the rating or tempt the study person to "rate by the watch".

Since the rating of an element represents the assessment of the average rate of performance for that element, the longer the element the more difficult it is for the study person to adjust this judgement to that average. This is a strong argument in favour of making elements short. Long elements, though timed as a whole up to the break points, should be rated every half-minute.

Rating to the nearest five is found to give sufficient accuracy in the final result. Greater accuracy than this can be attained only after very long training and practice.

We have discussed the filling-in of two columns, namely "Watch reading" (WR) and "Rating" (R), both entries being made on the same line. These readings are continued for a sufficient number of cycles.  The study is then at an end. The next step, after thanking the operative for his or her cooperation, is to work out the basic time for each element. How to do this is described in the next chapter.


Updated on 27.8.2021,  7 September 2020,  29 October 2019, 3 August 2019







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