Work Systems Design: Does it include design of machine work? Or is its focus only human work?
Work System: Definition
"A work system is a system in which human participants and/or machines perform work using information, technology, and other resources to produce products and/or services for internal or external customers." (IISE Work Systems Division)
The above definition indicates that an engineering work system, can be totally manual, or mechanized (machines operated by men) or totally automatic.
Work system is designed, resources are procured and operated with the objective of producing products or services. The design of work system starts after a product or services is determined to be produced.
As part of the work system design, the machines, work holding devices, and tools have to be designed or selected from those available in the market. The machine method or process plans have to be prepared. Work holding and tooling decisions have to be made based on the process plans. Where required outsourcing or buy decisions for certain parts that could be made inside also have to be made. The skills of operators required have to be determined. Work station design for each machine to facilitate operator's work has to be designed. Operator method for each work station has to be developed. Based on the flow of work in the processes and work station layout for each machine, plant layout has to be designed. Work measurement has to be used to prescribe times for machine elements and manual elements.
Professor Ralph Barnes, in his book Motion and Time Study, seventh edition, described the process of work system design.
Chapter 5 titled "Work Methods Design - The Broad View" deals with the work system design.
Summary of the approach
In early days of producing parts of engineering discipline, craftsmen processed materials into usable products using simple hand tools. Machines were invented gradually and factory system evolved to produce large quantities using machines operated by trained machinists. F.W. Taylor, advocated that in factory systems, managers have an important role to develop science of work related to each element used in factory production using modern methods of scientific investigation. Invention of better and more productive machines, cutting tools, jigs & fixtures aided in increasing the productivity of the factory worker resulted in higher incomes to employees of the factory compared craft-based production. Barnes commented at that time that the popular current processes of production utilize machines and workers. Barnes also recognized in his book, the existence of automatic machines, where manual involvement is minimal in the processing on the machine.
Work system design is a part of putting a new product or service into production. The product design to production task is done in three steps.
1. Planning
2. Pre-production
3. Production
1. Planning
Steps in planning
1. Design of the product: The output of the product design process is the set of drawings showing the material, shape, size, weight and tolerances of each part of the product.
2. The design of the process (process planning - machine method): The operations to be done to produce each part and do subassemblies and final assembly have to be determined. In the case of manufacturing of products there are primary processes of casting and processes for producing general materials like bars and sheets. The subsequent secondary operations like machining, forging and sheet metal operations produce the actual part as per design.
3. The selection or design of equipment: Based on the process plan proposed the selection of machines has to be done from the market availability or special purpose equipment has to be designed.
4. Design of tooling: Apart from the main machine selection, tools like work holding devices, cutting tools, tool holders, dies and inspection gauges are to be designed.
5. Decisions regarding supply of various utilities and facilities for supplying them have to be planned.
6. The operator method (work method) is to designed now by determining the role of the operator in running the machine. The work place layout around the machine has to be determined at this stage so that the location of the incoming and outgoing material, positioning of the tools etc. are designed to facilitate operator motions.
Operator method (work method): How the operator has handle the material, tools and machine controls.
7. Selection and design of material handling equipment.
8. The material that results from the process plan and the required quantity of production has to be combined with work station layouts the create the plant layout to minimize material handling.
Location of equipment, tooling, stock supply, utilities (electricity, gas, water), material handling equipment. Work space for operator motions and material movement.
9.The determination of the time required to do each operation has to be established.
Establishment of times for mechanical elements.
Operator activity
Cost estimates
Overall labor control for time.
We can observe iterative nature of the above activities. There is a need to revise earlier steps based on the issues uncovered at later steps. Sometimes decisions are taken for two steps together.
Pre-production
The information generated in planning phase has to be converted into organization of resources. Machines & tools, equipment are to be purchased and installed. Operators are to be selected and trained as per the process plans. Machines are put on trails. The planned operator methods are evaluated for effectiveness and efficiency. The actual times is checked against estimates or predetermined times. This is a period, that establishes the effectiveness and capacity of the process, equipment and operators.
Production
It is the operations phase. The project of creating production system or work system is completed and it is handed over to the operations team of managers, engineers, supervisors and operators. The regular flow of job orders based on customer orders or sales is established. Material purchases and supply take place and the machine-man-material system produces the products and services for which the system is designed.
During operations, there is necessity for preventing the methods from deteriorating from the planned methods. The current methods are to be evaluated against new developments in engineering, technology, new models of machines and tools for improvement opportunities. The potential for creative modifications of methods has to be identified. All operators are to be involved in method improvement to contribute their knowledge, thinking and experience. This is the prime job of industrial engineering. Continuous improvement of engineering over the product and process life cycles.
The phase of planning can be termed industrial system engineering and the improvement activity during operations is termed industrial engineering.
Work Systems Design - Related articles
Basic Steps in Work Systems Design - Prof. Gerald Nadler - 1963
Principles of Work System Design
Work Systems - Definition and Evolution of Work Systems Design in Industrial Engineering
Ud. 6.4.2022
Pub: 7.11.2020
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