Chapter 4 in 7th edition
10.5.2022
All operations managers are designers, because design is the process of satisfying people’s requirements through shaping or configuring products, services and processes.
Definition of ‘design’, we take it to mean ‘the process by which some functional requirement of people is satisfied through the shaping or configuration of the resources and/or activities that comprise a product, or a service, or the transformation process that produces them’. All operations managers are designers. When they purchase or rearrange the position of a piece of equipment, or when they change the way of working within a process, it is a design decision because it affects the physical shape and nature of their processes.
WHAT IS PROCESS DESIGN?
To ‘design’ is to conceive the looks, arrangement, and workings of something before it is created . In that sense it is a conceptual exercise. Yet it is one which must deliver a solution that will work in practice.
At the start of the process of design activity it is important to understand the design objectives, especially at first, when the overall shape and nature of the process is being decided. The most common way of doing this is by positioning it according to its volume and variety characteristics. Eventually the details of the process must be analysed to ensure that it fulfils its objectives effectively. Yet, it is often only through getting to grips with the detail of a design that the feasibility of its overall shape can be assessed. But don’t think of this as a simple sequential process. There may be aspects concerned with the objectives, or the broad positioning of the process, that will need to be modified following its more detailed analysis.
WHAT OBJECTIVES SHOULD PROCESS DESIGN HAVE?
The whole point of process design is to make sure that the performance of the process is appropriate for whatever it is trying to achieve. For example, if an operation competed primarily on its ability to respond quickly to customer requests, its processes would need to be designed to give fast throughput times.
Similarly, if an operation competed on low price, cost-related objectives would be likely to dominate its process design.
More ‘micro’ and detailed set of objectives.
These are largely concerned with flow through the process. When whatever are being ‘processed’ enter a process they will progress through a series of activities where they are ‘transformed’ in some way. Between these activities they may dwell for some time in inventories, waiting to be transformed by the next activity. This means that the time that a unit spends in the process (its throughput time) will be longer than the sum of all the transforming activities that it passes through. Also the resources that perform the process’s activities may not be used all the time because not all items will necessarily require the same activities and the capacity of each resource may not match the demand placed upon it. So neither the items moving through the process, nor the resources performing the activities may be fully utilized. Because of this the way that items leave the process is unlikely to be exactly the same as the way they arrive at the process. It is common for more ‘micro’ performance flow objectives to be used that describe process flow performance. For example:
● Throughput rate (or flow rate) is the rate at which items emerge from the process, i.e. the number of items passing through the process per unit of time.
‘Paced’ processes like moving belt assembly lines. It is the ‘beat’, or tempo, of working required to meet demand.
● Throughput time is the average elapsed time taken for inputs to move through the process and become outputs.
● The number of items in the process (also called the ‘work in progress’, or in-process inventory), as an average over a period of time.
● The utilization of process resources is the proportion of available time that the resources within the process are performing useful work.
Standardization is also an important objective in the design of some services and products, for similar reasons. The practical dilemma for most organizations is how to draw the line between processes that are required to be standardized, and those that are allowed to be different.
There is a continuum from low volume/high variety through to high volume/low variety, on which we can position processes. For each operation to be done in a process there could be processes with very different positions on this volume–variety spectrum.
Process types
Project processes
Jobbing processes
Batch processes
Mass and Bulk processes
Mass and Lean Processes
Continuous processes
● Cycle time, or takt time, is the reciprocal of throughput rate – it is the time between items emerging from the process. The term ‘takt’ time is the same, but is normally applied to
The product–process matrix
The most common method of illustrating the relationship between a process’s volume– variety position and its design characteristics is the ‘ product– process’ matrix. It can be used for any type of process whether producing products or services. The underlying idea of the product–process matrix is that many of the more important elements of process design are strongly related to the volume–variety position of the process. So, for any process, the tasks that it undertakes, the flow of items through the process, the layout of its resources, the technology it uses, and the design of jobs, are all strongly influenced by its volume–variety position.
DETAILED PROCESS DESIGN
After the overall design of a process has been determined, its individual activities must be configured. At its simplest, this detailed design of a process involves identifying all the individual activities that are needed to meet the objectives of the process, and deciding on the sequence in which these activities are to be performed and who is going to do them. There will, of course, be some constraints to this. Some activities must be carried out before others and some activities can only be done by certain people or equipment. Nevertheless, for a process of any reasonable size, the number of alternative process designs is usually large. Because of this, process design is often done using some simple visual approach, such as process mapping.
Process mapping
Process mapping simply involves describing processes in terms of how the activities within the process relate to each other. There are many techniques which can be used for process mapping (or process blueprinting, or process analysis, as it is sometimes called).
Different levels of process mapping
For a large process, drawing process maps at this level of detail can be complex. This is why processes are often mapped at a more aggregated level, called high-level process mapping, before more detailed maps are drawn.
At the highest level the process can be drawn simply as an input–transformation–output process with materials and customers as its input resources and lighting services as outputs. No details of how inputs are transformed into outputs are included. At a slightly lower or more detailed level, what is sometimes called an outline process map (or chart) identifies the sequence of activities but only in a general way.
At the more detailed level, all the activities are shown in a ‘detailed process map’ Although not shown in Figure 4.8, an even more micro set of process activities could be mapped within each of the detailed process activities. Such a micro-detailed process map could specify every single motion involved in each activity.
Some activities, however, may need mapping in more detail to ensure quality or to protect the company’s interests. For example, the activity of safety-checking the customer’s site to ensure that it is compliant with safety regulations will need specifying in some detail to ensure that the company can prove it exercised its legal responsibilities.
Throughput time, cycle time and work in progress
So far we have looked at the more conceptual (process types) and descriptive (process mapping) aspects of process design. We now move on the equally important analytical perspective.
Little’s law
This mathematical relationship (throughput time = work-in-progress * cycle time) is called Little’s law. It is simple but very useful, and it works for any stable process. Little’s law states that the average number of things in the system is the product of the average rate at which things leave the system and average time each one spends in the system. Or, put another way, the average number of objects in a queue is the product of the entry rate and the average holding time.
Throughput efficiency
This idea that the throughput time of a process is different from the work content of whatever it is processing has important implications.
Percentage throughput efficiency = [Work content/Throughput time] * 100
Value-added throughput efficiency restricts the concept of work content to only those tasks that are literally adding value to whatever is being processed. This often eliminates activities such as movement, delays and some inspections.
Workflow
When the transformed resource in a process is information (or documents containing information), and when information technology is used to move, store and manage the information, process design is sometimes called ‘workflow’ or ‘workflow management’.
SUMMARY - KEY QUESTIONS
What is process design?
What objectives should process design have?
How do volume and variety affect process design?
How are processes designed in detail?
Proposed Procedure for Process Design and Communication
1. First Specify the output required. Find out indicated volume for annual production.
2. Determine possible inputs.
3. For each input determine the material transformation stages (Find out the best machine available in the market for various volume levels. Incorporate existing machines in the company also in the proposal. Incorporate pure manual method also as an alternative).
4. Subject the initial proposal to technical feasibility analysis.
5. Do cost analysis for each alternative.
6. Select techno-economically feasible alternative for each operation in the process.
7. Decide quality related inspection activities for each material transformation operation.
8. Find out the best possible instruments for the inspection and related data processing. Incorporate existing instruments and pure manual alternatives also.
9. Subject the initial proposal to technical feasibility analysis.
10. Do cost analysis for each alternative.
11. Select techno-economically feasible alternative for each operation in the process.
12. Determine tentative batch quantity for manufacture.
13. Determine working process storage provision required. Determine the storage facility after techno-economic analysis including best facility currently available and existing facilities.
14. Determine the transport of material required between machine, inspection station and storage location.
15. Indicate the equipment to be used for transportation. Incorporate best possible equipments, existing equipments, and pure manual alternatives also.
16. Subject the initial proposal to technical feasibility analysis.
17. Do cost analysis for each alternative.
18. Select techno-economically feasible alternative for each operation in the process.
19. Present the complete process as a flow process chart.
This flow process chart is still a high level chart.
Each operation has to be designed and documented further. At the lowest level each element of machine work and manual motion are to be specified and even the motion patter needs to be specified.
SELECTED FURTHER READING
Chopra, S. , Anupindi, R. , Deshmukh, S.D. , Van Mieghem, J.A. and Zemel, E. ( 2012 ) Managing
Business Process Flows, 2nd edn , Prentice Hall, Upper Saddle River, NJ. An excellent, although
mathematical, approach to process design in general.
Hammer, M. ( 1990 ) Reengineering Work: Don’t automate, obliterate, Harvard Business Review , July–August. This is the paper that launched the whole idea of business processes and process management in general to a wider managerial audience. Slightly dated but worth reading.
Hopp, W.J. and Spearman, M.L. ( 2001 ) Factory Physics, 2nd edn, McGraw-Hill, New York. Very technical so don’t bother with it if you aren’t prepared to get into the maths. However, some fascinating analysis, especially concerning Little’s law.
Smith, H. and Fingar, P. ( 2003 ) Business Process Management: The Third Wave , Meghan-Kiffer Press, Tampa, FL. A popular book on process management from a BPR perspective.
The Basics of Process Mapping, 2nd Edition
By Robert Damelio
https://books.google.co.in/books?id=I6O_Z-dTap8C
Design and management of service processes
by Ramaswamy, Rohit,
Publication date 1996
Includes bibliographical references (pages 411-414) and index
Ch. 1. Designing Services -- an Introduction -- Ch. 2. The Service Design and Management Model -- A Methodological Overview -- Ch. 3. Developing Design Specifications -- Part 1: Defining Design Attributes -- Ch. 4. Developing Design Specifications -- Part 2: Setting Design Performance Standards -- Ch. 5. Generating and Evaluating Design Concepts -- Ch. 6. Performing Detailed Process Design -- Part 1: Generating Design Alternatives -- Ch. 7. Performing Detailed Process Design -- Part 2: Evaluating and Testing Alternatives -- Ch. 8. Implementing the Design -- Ch. 9. Measuring Performance -- Ch. 10. Assessing Customer Satisfaction -- Ch. 11. Improving Service Performance -- Ch. 12. Conclusion
Ud. 15.9.2024, 30.7.2023, 11.7.2023
Pub 10.5.2022
Great information thanks
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