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P
rocess design
Source: Joe Schwarz, www.joyrides.com
Process design
Operations strategy Design Improvement Planning and control Operations management Process designSupply network design Layout and flow Process technology Job design Product/service design
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Nature and purpose of the design activity
Products, services and the processes which produce them all have to be designed
Decisions taken during the design of a product or service will have an impact on the decisions taken during the design of the process which produces those products or services, and vice versa
Products and services should be designed in such a way that they
can be created effectively
Designing the product or service
Processes should be designed so they can create all products and services which the operation is likely
to introduce Designing the process Product / service design has an impact on the process design and
vice versa
Design of products / services and design of processes are interrelated and should be treated together
3 Design of the Service Design of the Process Design of the Product Design of the Process
In most service operations the overlap between service
and process design is implicit in the nature of
service In manufacturing operations
overlapping the activities of product and process design
is beneficial
Delay (a wait, e.g. for materials) Operation (an activity that directly adds value)
Inspection (a check of some sort)
Transport (a movement of something)
Storage (deliberate storage, as opposed to a delay)
Process mapping symbols derived from ‘Scientific
Management’
Decision (exercising discretion)
Process mapping symbols derived from Systems Analysis
Direction of flow Input or output from the process
Activity
Beginning or end of the process
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Designing processes
There are different ‘process types’
Process types are defined by the volume and
variety of ‘items’ they process
Process types go by different names
depending on whether they produce products or
services
High Volume Low High Variet y Project Lo wManufacturing process types
Process tasks Process flow Diverse/ complex Repeated/ divided Intermittent Continuous Jobbing Batch Mass Contin-uous
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One-off, complex, large-scale ‘products’ with
high work content
Specially made, every one ‘customized’
Defined start and finish: time, quality and cost
objectives
Many different skills have to be coordinated
Project processes
A project process with a small part of the process map that would describe the whole process
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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, completes whole
product
Jobbing processes
Preparing photolithography materials on a jobbing basis with a typical process map
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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
A batch process in a kitchen together with an illustrative process map
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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
Part of a continuous process and a typical process map
10 Volume Low High Variet y Lo w High
Service process types
Process tasks Process flow Diverse/ complex Repeated/ divided Intermittent Continuous Professional service Service shop Mass service A professional service –
11 A service shop – This health club offers some variety
within a standard set of facilities and processes
A mass service – This call centre can handle a very high volume of customer enquiries because it
standardizes its process
12 Deviating from the ‘natural’ diagonal on the product–process
matrix has consequences for cost and flexibility
None None Less process flexibility than is needed so high cost More process flexibility than is needed so high cost
The ‘natural’ line of fit of process to volume/variety characteristics Project Jobbing Batch Mass Continuous Manufacturing operations process types Professional service Service shop Mass service Service operations process types Variety Volume
Deviating from the ‘natural’ diagonal on the product–process matrix has consequences for cost and flexibility
None None Variety Volume Old process Old process, new product New process, new product
13 Flow (layout), technology and job design are all influenced
by process positioning None None Variety Volume Machine tool maker Custom furniture maker Automobile factory Petro-chemical refinery
Flow Technology Jobs
Unorganized Predictable Little / general Specialist Varied / high discretion Routine / low discretion
Flow (layout), technology and job design are all influenced by process positioning
None
None
Variety Volume
Flow Technology Jobs
Unorganized Predictable Little / general Specialist Varied / high discretion Routine / low discretion Customer service branch Investment banking Bank call centre Credit card processing
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Delay (a wait, e.g. for materials) Operation (an activity
that directly adds value)
Inspection (a check of some sort)
Transport (a movement of something)
Storage (deliberate storage, as opposed to a delay)
Process mapping symbols derived from ‘Scientific
Management’
Decision (exercising discretion)
Process mapping symbols derived from Systems Analysis
Direction of flow Input or output from the process
Activity
Beginning or end of the process
Standard sandwich process Raw materials Assembly Stored sandwiches Move to outlets Stored sandwiches Customer request Sell Take payment Customized sandwich – old process
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Raw materials
Take payment
Customized sandwich – old process
Customer request Assembly
The operation of making and selling customized sandwiches
Outline process of making and selling customized sandwiches
Prepare Assemble as required Take payment Bread and base filling Stored ‘bases’ Fillings Assemble whole sandwich Customer request Use standard ‘base’? Assemble from standard ‘base’ No Yes Detailed process of assembling customized sandwiches Sandwich materials and customers Customers ‘assembled’ to sandwiches
16 Bread and base filling Assembly of ‘sandwich bases’ Assemble from standard ‘base’ Take payment Assemble whole sandwich Customer request Use standard ‘base’? No Yes Fillings Stored ‘bases’
Customized sandwich – new process
Reports to batch control Reports filed Payment voucher to keying
Confirm payment Report arrives Stamp and date report Check expenses report
Wait for processing Check reports and vouchers Attach payment voucher Collect retorts into batch
Batch control number Batch to audit desk Wait for batching
Copy of reports to filing
Description of activity Totals 8 1 2 4 5 6 7 9 10 3 11 12 14 15 13 5 5 2 2 1
Send to accounts receivable
Reports to batch control Reports filed Confirm payment Report arrives Stamp and date report Send cash to receipt desk Wait for processing Check expenses report Wait for processing Check employee record Check advance payment Send to account payable Wait for processing Attach payment voucher Collect retorts into batch Check against rules Wait for processing
Batch control number Check payment voucher Log report
Batch to audit desk Wait for batching Batch of reports logged Copy of reports to filing
Description of activity Totals 8 1 2 4 5 6 7 9 10 3 18 11 12 14 15 16 17 19 20 13 26 22 23 24 25 21 7 8 5 5 1
Payment voucher to keying
Flow process charts for processing expense reports at Intel before and after improving the process
17 Throughput (TH) = Work in process (WIP) × Cycle time (CT)
Little’s law (a really quite useful law)
Cycle time = 2 minutes
Throughput time = ? WIP = 10
Throughput time = 10 × 2 minutes = 20 minutes
Throughput (TH) = Work in process (WIP) × Cycle time (CT)
Little’s law (a really quite useful law)
Throughput time = 5 days × 7 hours = 35 hours
500 exam scripts need to be marked in 5 days (working 7 hours a day). It takes 1 hour to mark a script. How many markers are needed?
35 hours = 500 scripts × Cycle time Cycle time = 35 hours
500 scripts = 0.07 hours
Number of markers = Work content = 1 hour = 14.29
18 Throughput efficiency = Work content
Throughput time × 100
Throughput efficiency is the work content of whatever is being processed as a percentage of its throughput time
Throughput efficiency
0 20% 40% 60% 80% 100% Capacity utilization Low X X X High utilization but long throughput timesLow utilization but short throughput times
Reduce process variability High 10 mins 30 mins Arrival frequency (demand) Processing time Utilization = 33.33 % Q = 0 Av era g e le ngth of que ue X Utilization = 50 % Q = 0 20 mins X 10 mins Utilization = 100 % Q = 0 X Utilization = 100 % Q = infinity 9 mins X 5–15 mins 5–15 mins Arrival frequency (demand) Processing time Utilization < 100% Q > 0 Process throughput time (or in v e ntory )
19 10 20 30 40 50 60 70 80 90 100 0 Utilization Average number of units w a iting to be p ro c essed Decreasing variability 10 20 30 40 50 60 70 80 90 100 0 Utilization Average number of units w a iting to be p ro c essed X Y Z High utilization but long waiting
time Reduction in
process variability Short waiting
time but low utilization
(a) Decreasing variability allows higher utilization without long waiting times
(b) Managing process capacity and/or variability
The relationship between process utilization and number of units waiting to be processed for variable arrival and
activity times
Key Terms Test
Throughput time
The time for a unit to move through a process.
Utilization
The ratio of the actual output from a process or facility to its design capacity.
Life cycle analysis
A technique that analyzes all the production inputs, the life cycle use of a product and its final disposal in terms of total energy used and wastes emitted.
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Key Terms Test
Process types
Terms that are used to describe a particular general approach to managing processes. In manufacturing these are generally held to be project, jobbing, batch, mass and continuous processes; in services they are held to be professional services, service shops and mass services.
Project processes
Processes that deal with discrete, usually highly customized, products.
Jobbing processes
Processes that deal with high variety and low volumes, although there may be some repetition of flow and activities.
Key Terms Test
Batch processes
Processes that treat batches of products together, and where each batch has its own process route.
Continuous processes
Processes that are high volume and low variety; usually products made on continuous processes are produced in an endless flow, such as petrochemicals or electricity.
Professional services
Service processes that are devoted to producing knowledge-based or advice-knowledge-based services, usually involving high customer contact and high customization. Examples include management consultants, lawyers, architects, etc.
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Key Terms Test
Service shops
Service processes that are positioned between professional services and mass services, usually with medium levels of volume and customization.
Mass services
Service processes that have a high number of transactions, often involving limited customization, for example mass transportation services, call centres, etc.
Product–process matrix
A model derived by Hayes and Wheelwright that demonstrates the natural fit between volume and variety of products and services produced by an operation on one hand, and the process type used to produce products and services on the other.
Key Terms Test
Process mapping
Describing processes in terms of how the activities within the process relate to each other (may also be called process blueprinting or process analysis).
Process mapping symbols
The symbols that are used to classify different types of activity, usually derived either from scientific management or from information systems flowcharting.
High-level process mapping
An aggregated process map that shows broad activities rather than detailed activities (sometimes called an outline process map).
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Key Terms Test
Work content
The total amount of work required to produce a unit of output, usually measured in standard times.
Throughput time
The time for a unit to move through a process.
Cycle time
The average time between units of output emerging from a process.
Key Terms Test
Work-in-process
The number of units within a process waiting to be processed further (also called work-in-progress).
Little’s Law
The mathematical relationship between throughput time, work-in-process and cycle time:
