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Chapter 6

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Lesson Discussion:

Process Design
Chapter 6
Learning Outcomes

▪ Define process design


▪ Discuss the objectives of
process design
▪ Understand how volume and
variety affecting the process
design
▪ Describe the processes design
in detail
Process Design

➢ To ‘design’ is to conceive the looks, arrangement and workings


of something before it is created.
➢ It is a conceptual exercise that must deliver a solution that will
work in practice
➢ Design is also an activity that can be approached at different
levels of detail.
➢ One may envisage the general shape and intention of
something before getting down to defining its details.
➢ It is important to understand the design objectives, especially
when the overall shape and nature of the process are being
decided.
What is process design?

 Design is the activity which


shapes the physical form and
purpose of both products and
services and the processes
that produce them.
 The design activity is more
likely to be successful if the
complementary activities of
product or service design and
process design are
coordinated.
What should be the objectives of
process design?

 The overall purpose of process design is to meet the needs


of customers through achieving appropriate levels of
quality, speed, dependability, flexibility and cost.
 The design activity must also take account of
environmental issues.
 These include examination of the source and suitability of
materials, the sources and quantities of energy consumed,
the amount and type of waste material, the life of the
product itself, and the end-of-life state of the product.
What should be the objectives of
process design?

➢ Operations principle: process flow objectives should


include throughput rate, throughput time, work-in
progress and resource utilization, all of which are
interrelated.

➢ Throughput rate (or flow rate) is the rate at which items emerge
from the process, that is the number of items passing through the
process per unit of time.
➢ 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 ‘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.
What should be the
objectives of process
design?
➢ Operations principle: standardizing processes can
give some significant advantages, but not every
process can be standardized
➢ Standardization means ‘doing things in
the same way’ or, more formally, ‘adopting
a common sequence of activities, methods
and use of equipment’.
➢ But why not allow many different ways of doing the same
thing? That would give a degree of autonomy and
freedom to individuals and teams to exercise their
discretion. The problem is that allowing numerous ways of
doing things causes confusion, misunderstandings and,
eventually, inefficiency.
What should be the
objectives of process
design?
➢ Operations principle: the design of any process should
include consideration of ethical and environmental issues
➢ With the issues of environmental protection becoming more
important, process designers have to take account of ‘green’
(sustainability) issues.
➢ To help make more rational decisions in the design activity, some
industries are experimenting with life cycle analysis. This technique
analyses all the production inputs, the life cycle use of the product
and its final disposal, in terms of total energy used and all emitted
wastes.
How do volume and
variety affect process
design?
 The overall nature of any process is strongly influenced by the
volume and variety of what it has to process.
 The concept of process types summarizes how volume and
variety affect overall process design.
 In manufacturing, these process types are (in order of
increasing volume and decreasing variety) project, jobbing,
batch, mass and continuous processes.
 In service operations, although there is less consensus on the
terminology, the terms often used (again in order of increasing
volume and decreasing variety) are professional services,
service shops and mass services.
Process type

➢ The position of a process on the volume–variety continuum


shapes its overall design and the general approach to
managing its activities. These ‘general approaches’ to
designing and managing processes are called process types.
➢ Project processes
➢ deal with discrete, usually highly customized products, often with a relatively long timescale
between the completion of each item, where each job has a well-defined start and finish.
Project processes have low volume and high variety.
➢ Jobbing processes
➢ also deal with high variety and low volumes. However, while in project processes each item has
resources devoted more or less exclusively to it, in jobbing processes each product has to share the
operation’s resources with many others.

➢ Batch processes
➢ may look like jobbing processes, but do not have the same degree of variety. As the name implies,
each time batch processes produce more than one item at a time. So each part of the process has
periods when it is repeating itself, at least while the ‘batch’ is being processed.
Process type

➢ Continuous processes
➢ have even higher volume and usually lower variety than mass processes. They also
usually operate for longer periods of time. Sometimes they are literally continuous in
that their products are inseparable, being produced in an endless flow. They often have
relatively inflexible, capital-intensive technologies with highly predictable flow.
➢ Professional services
➢ are high-contact processes where customers spend a considerable time in the service
process. These services can provide high levels of customization (the process being highly
adaptable in order to meet individual customer needs). Professional services tend to be
people based rather than equipment based, and usually staff are given considerable
discretion in servicing customers.

➢ Service shops
➢ have levels of volume and variety (and customer contact, customization and staff discretion)
between the extremes of professional and mass services

➢ Mass services
➢ have many customer transactions, involving limited contact time and little customization. Staff are likely to have
a relatively defined division of labor and have to follow set procedures.
How are processes
designed in detail?

 Processes are designed initially by breaking them down into their individual
activities.
 Often common symbols are used to represent types of activity.
 Process Mapping -The sequence of activities in a process is then indicated by
the sequence of symbols representing activities.
 Alternative process designs can be compared using process maps and
improved processes considered in terms of their operations performance
objectives.
 Process performance in terms of throughput time, work-in-progress and cycle
time is related by a formula known as Little’s law: throughput time equals work-
in-progress multiplied by cycle time .
 Variability has a significant effect on the performance of processes, particularly
the relationship between waiting time and utilization
Process mapping

➢ There are many techniques which can be used for


process mapping (or process blueprinting, or process
analysis).
➢ Process mapping symbols -are used to classify different types of
activity. There is no universal set of symbols. These symbols can
be arranged in order, and in series or in parallel, to describe any
process.
➢ Process mapping is needed to expose the reality of process behavior
➢ 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.
➢ Some activities, however, may need mapping in more detail to
ensure quality or to protect the company’s interests.
Process mapping

 Process visibility
 It is sometimes useful to map such processes in a way that
makes the degree of visibility of each part of the process
obvious.
 This allows those parts of the process with high visibility to be
designed so that they enhance the customer’s perception of
the process.
 Throughput time, cycle time and work-in-progress
 the first stage is to understand the nature of, and relationship
between, throughput time, cycle time and work-in-progress.
 As a reminder; throughput time is the elapsed time between
an item entering the process and leaving it; cycle time is the
average time between items being processed; and work-in-
progress is the number of items within the process at any
point in time.
Little’s law (John Little)

 This mathematical relationship


(throughput time = work-in-progress ×
cycle time)
 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
Value-added throughput efficiency
 The approach to calculating throughput efficiency
assumes that all the ‘work content’ is actually needed.
Therefore, work content is actually dependent upon the
methods and technology used to perform the task.
 It may be also that individual elements of a task may
not be considered ‘value-added’.
 So, value-added throughput efficiency restricts the
concept of work content to only those tasks that are
literally adding value to whatever is being processed.
 For example, if, in the licensing worked example, of the
25 minutes of work content only 20 minutes was
actually adding value, then:
Workflow
 When the transformed resource in a process is information, and
when information technology is used to move, store and manage
the information, process design is sometimes called ‘workflow’ or
‘workflow management’.
 It is defined as ‘the automation of procedures where documents,
information or tasks are passed between participants according to
a defined set of rules to achieve, or contribute to, an overall
business goal’.
Workflow is Concerned with the Following:
▪ Analysis, modeling, definition and subsequent operational
implementation of business processes.
▪ The technology that supports the processes.
▪ The procedural (decision) rules that move information/documents
through processes.
▪ Defining the process in terms of the sequence of work activities,
the human skills needed to perform each activity and the
appropriate IT resources.
Process bottlenecks

 A bottleneck in a process is the activity or stage where congestion


occurs because the workload placed is greater than the capacity to
cope with it.

 Balancing work time allocation


 Allocating work to process stages must respect the ‘precedence’ of the
individual tasks that make up the total work content of the job that the
process is performing.
Arranging the stages
 All the stages necessary to fulfill the requirements of the process may not
be arranged in a sequential ‘single line‘.

In any particular situation there are usually


technical constraints which limit either how ‘long
and thin’ or how ‘short and fat’ the process can
be, but there is usually a range of possible
options within which a choice needs to be made
.
 Two fundamental types of variability
 Variability in the demand for processing at an individual stage
within the process, usually expressed in terms of variation in the
inter-arrival times of items to be processed.
 Variation in the time taken to perform the activities (that is,
process a unit) at each stage.
❖ Variability in a process acts to reduce its efficiency
❖ Process variability results in simultaneous waiting and resource
under-utilization
❖ Process analysis derives from an understanding of the required
process cycle time

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