Production & Operation Management

1. CHAPTER 29: Cellular Manufacturing
Responses to Questions
1. Cellular manufacturing makes it possible to have a variety of products with
reduced flow times and with better control over quality. These results can
be of great strategic value to any firm.
2. Yes; to an extent. But, the marginal increase in capital investment is
compensated several times over through increases in productivity, and in
responsiveness and flexibility of the operations system.
3. The basic disadvantages of a line layout are: (i) its inflexibility and (ii) lack
of variety of products. If the cell formation principles are diligently followed,
these drawbacks can be overcome.
4. Cell members can get insulated from the other cells and production-
related departments. Within a cell too, there should a ‘sociable’ number of
people. People in a cell should be comfortable working with each other
and in developing multiple skills. All this needs much human relations
training.
5. Management needs to delegate responsibility to the group of employees
in the cell. There is much less control by the management. Most decisions
are made by the cell members; management indicates the vital result
areas and expected level of results including some hard figures on
required amount and type of production. However, otherwise the group
manages itself.
6. Human aspects are vital: group size, group harmony, group orientation
and group motivation.
7. Cellular manufacturing, in fact encourages individual initiative. Moreover,
because of its inherent flexibility, a cell can accommodate a new product
design.
8. Similar to a module – a small group of parts providing a function, a cell
has a group of parts manufactured providing a part of a line of products
manufactured by the firm. Just as in modular design, the cell concept
allows easier changes in the production process or in product.
Also, just as a module with a problem can be easily replaced with another,
a cell having problem can be temporarily stopped functioning and the work
can be redirected to another cell.

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9. The grouping is done in such a way that there are:
a. a maximum number of key facilities fully utilized.
b. a minimum number of underutilized facilities.
c. a maximum number of fully utilized operators.
Constraints are capacities of each facility and the set of routes through
different facilities (equipment). Variables are the jobs/products to be
routed through the facilities.
10.A JIT production line could have many GT cells feeding into it. GT is
capable of producing a given variety of items on demand. While GT is
generally operated as ‘Push’ system, due to its inherent flexibility a GT cell
can be operated on a ‘Pull’ system as well. However, set-up time
reduction technology has to be mastered for the operation of the ‘pull’
system.
11. Facilities layout can contribute to either a separation of people or to
frequent and free interactions between people. Physical barriers could
amount to communication barriers; on the other hand, a physical facility
can create opportunities for people to meet and mingle. This is true for
insiders as well as for the outsiders (e.g. customers).
12.GT has its emphasis on ‘Group.’ This group is not only of machines but
equally importantly of the people who work with the machines. Group
dynamics is of tremendous significance in the productivity of a ‘Cell.’ It is
the people who produce productivities, in the ultimate analysis.
13.GT can be used to group various tasks – if such grouping is possible. It is
of much use in Job Redesign. It is also of use in forming work stations on
an assembly line. It is of use in grouping tasks in a service industry – e.g.
Group of tasks that a qualified nurse could do, an auxiliary nurse midwife
could do, a receptionist could do, a bank teller could do or booking counter
clerk in Railways could do.
14.Opitz system is based on ‘operations’ and hence is very useful in GT.
However, there are other systems of codification and classification such
as the Kodak system, Brisch system etc which are less operations
oriented. The purpose in many of these cases is unique identification and
assistance in storage and easy retrieval from the stores. The purpose
behind codification and classification is important.
15.Yes. Nowadays there are many health checkup packages. These are
similar to products. Similar ‘family’ of such products can be grouped and
put into a GT cell comprising the required equipment, consultants,
operatives, nurses and other staff.

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16. Grouping should be optimal so as to offer maximum merits and minimum
demerits. The operations to group, the people and skills to group etc
should be based on much thought for the pros and cons. What is seen as
some rigidity could be more than compensated by the speed of response
and by the rapid throughput times. Partial loss of one kind of flexibility
(say, variety of products) could be overweighed completely by the time
flexibility (e.g. filling a customer requirement speedily).

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Chapter 29: Cellular Manufacturing
Objective Questions
1. ‘Mitrofanov’ grouping involves:
a. several components and several machines.
b. several machines but single component.
√c. several components and single machine.
d. single component and several machines.
2. Cell design can be based on:
a. Classification and codification
b. Production Flow analysis
c. Component Flow analysis
√d. any of the above
3. Opitz is:
√a. a system of codification
b. a name of a composite component
c. a system of component flow analysis
d. none of the above
4. A ‘composite component’ is:
a. the component that has the largest customer demand.
b. a sub-assembly of various parts made in a cell.
√c. a hypothetical concept but very useful in developing tooling layouts
on machines.
d. none of the above.
5. The comparison between Group Technology and Cellular Manufacturing is
as follows:
a. Cellular manufacturing and Group Technology are identical.
b. Cellular manufacturing is a broader concept that can be used
profitably in Group Technology.
√c. Group Technology is a broader concept that can be used in Cellular
manufacturing..
d. Group Technology and Cellular manufacturing are entirely different.
6. A ‘Product layout’:
√a. has short throughput time.
b. has considerable flexibility to change.
c. needs large inventories.
d. none of the above.
7. Component Flow analysis is used for:
a. conceptualizing a Composite element.

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b. arriving at a Family of Parts.
√c. cell design.
d. classification and codification.
8. Cell design can be based on:
a. shapes and features of parts.
b. needed flows through different machines.
c. linear programming.
√d. all of the above.
9. JIT and Cellular manufacturing:
a. are one and the same.
√b. combine properties of line and process layout.
c. entirely different.
d. are used predominantly in precision parts manufacturing.
10.Cellular manufacturing is about:
a. layout of machines.
b. flows of material.
√c. all of the above.
d. none of the above.
11.In the context of Cellular manufacturing, a ‘pack’ is:
√a. group of components.
b. group of machines.
c. group of workers.
d. group of suppliers.
12.Mitrofanov’s grouping was for:
a. grouping machines for a cell.
√b. grouping components for a single machine.
c. grouping ‘composite elements’ for a cell.
d. none of the above.
13.‘Cell size’ means:
a. number of machines in the cell.
b. number of people in the cell.
√c. number of machines and people in the cell.
d. shop-floor area of the cell.
14.An issue to be addressed during cell formation is of:
a. load balancing.
b. utilization of non-key machines.
c. placement of bottleneck machines.
√d. all of the above.

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15.The issue of ‘cell independence’ concerns:
a. the placement of bottleneck machine.
b. the utilization of non-key machines.
c. a & b
√d. none of the above.
16.‘Production flow analysis’ – in Cellular manufacturing – considers:
√a. flow of work.
b. design features of components.
c. shape of components.
d. all of the above.
17.When components are grouped into a ‘family’ of parts, it always leads to:
a. considerable reduction in set-up times.
b. balancing of load.
c. a & b
√d. none of the above.
18.A manufacturing cell is flexible when:
a. the cell is able to accommodate new parts.
b. parts can be processed on alternate machines inside the cell.
√c. all of the above.
d. none of the above.