operational excellence assignment
Chapter 6
Niccole Hyatt, PhD
Key Questions
What is process design?
What should be the objectives of process design?
How do volume and variety affect process design?
How are processes designed in detail?
Figure 6.2 The design of products/services and processes are interrelated and should be treated together
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| Operations performance objective | Typical process design objectives |
| Quality | Provide appropriate resources, capable of achieving the specification of product of services Error-free processing |
| Speed | Minimum throughput time Output rate appropriate for demand |
| Dependability | Provide dependable process resources Reliable process output timing and volume |
| Flexibility | Provide resources with an appropriate range of capabilities Change easily between processing states (what, how or how much is being processed?) |
| Cost | Appropriate capacity to meet demand Eliminate process waste in terms of excess capacity excess process capability in-process delays in-process errors inappropriate process inputs |
The impact of performance objectives on design
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| Operations performance objective | Some benefits of good process design |
| Quality | Products and service produced ‘on-specification’ Less recycling and wasted effort within the process |
| Speed | Short customer waiting time Low in-process inventory |
| Dependability | On-time deliveries of products and services Less disruption, confusion and rescheduling within the process |
| Flexibility | Ability to process a wide range of products and services Low cost/fast product and service change Low cost/fast volume and timing changes Ability to cope with unexpected events (e.g. supply or a processing failure) |
| Cost | Low processing costs Low resource costs (capital costs) Low delay/inventory costs (working capital costs) |
The impact of performance objectives on design
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Some fundamental issues:
The sources of inputs to a product or service. (Will they damage rainforests? use up scarce minerals? exploit the poor or use child labour?)
Quantities and sources of energy consumed in the process. (Do plastic beverage bottles use more energy than glass ones? Should waste heat be recovered and used in fish farming?)
The amounts and type of waste material that are created in the manufacturing processes. (Can this waste be recycled efficiently, or must it be burnt or buried in landfill sites?)
The life of the product itself. If a product has a long useful life will it consume fewer resources than a short-life product?
The end-of-life of the product. (Will the redundant product be difficult to dispose of in an environmentally friendly way?)
Environmentally sensitive process design
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One-off, complex, large scale and high work content ‘products’.
Specially made, every one customized.
Defined start and finish: time, quality and cost objectives.
Many different skills have to be coordinated.
Project processes
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Very small quantities: ‘one-offs’, or only a few required.
Specially made. High variety, low repetition. ‘Strangers’ every one customized.
Skill requirements are usually very broad.
Skilled jobber, or team, complete whole product.
Jobbing processes
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Higher volumes and lower variety than for jobbing.
Standard products, repeating demand. But can make specials.
Specialized, narrower skills.
Set-ups (changeovers) at each stage of production.
Batch processes
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Higher volumes than batch.
Standard, repeat products (‘runners’).
No set-ups, or almost instantaneous ones.
Low and/or narrow skills.
Mass (line) processes
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Extremely high volumes and low variety: often single product.
Standard, repeat products (‘runners’).
Highly capital-intensive and automated.
Few changeovers required.
Difficult and expensive to start and stop the process.
Continuous processes
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Questions?
Niccole Hyatt, PhD