2. PRODUCT LAYOUT:
In such type of layout, all the machines and processes concerned with the manufacturers of the same product
and the same product and the same range of grouped together .There machines are arranged according to the
sequence of operations. Product layout efficiency is often enhanced through the use of line balancing. Line
balancing is the assignment of tasks to workstations in such a way that workstations have approximately equal
time requirements. This minimizes the amount of time that some workstations are idle, due to waiting on parts
from an upstream process or to avoid building up an inventory queue in front of a downstream process.
Advantages of product layout are as follows:
1. Production planning and control becomes easier due to fixed sequence of operations.
2. This layout results in less material handling due to shorter distance to be travelled between two
consecutive workstations and it does not involve any material backtracking.
3. Maximum use floor space.
4. Total manufacturing cycles time is lesser due to smoother flow of work.
5. Lower work in process inventory.
6. Lesser time lost in machine setting.
7. It is easier to train workers on this layout due to single product flow.
8. Nature of job on the machines being highly repetitive, lesser skilled workmen can carry out such job thus,
there is saving in labour cost.
Disadvantage of product layout are as follows:
• Capital investment is very high due to under utilization and duplication of machines at many workstations
• Machine breakdown at any one workstation is likely to shut the whole production line.
• The layout being designed for catering to one type of product, any product change will make all the
machines obsolete.
• Utilization. Equipment utilization rates in process layout are frequently very low, because machine usage
is dependent upon a variety of output requirements.
• Cost. If batch processing is used, in-process inventory costs could be high. Lower volume means higher
per-unit costs. More specialized attention is necessary for both products and customers. Setups are more
frequent, hence higher setup costs. Material handling is slower and more inefficient. The span of
supervision is small due to job complexities (routing, setups, etc.), so supervisory costs are higher.
Additionally, in this type of layout accounting, inventory control, and purchasing usually are highly
involved.
• Confusion. Constantly changing schedules and routings make juggling process requirements more
difficult.
For example in the automobile industry Since a machine is assigned for each operation, the number of
equipment in a product layout is much more as compared to the Product layout is much more as compared to
the Process layout .Therefore ,the utilization of the equipment has to be sufficiently high to justify the higher
3. level of capital investment necessary in a Product layout .This means ,the volume of production should be large
and the variety of products should be low so that there is a very little time lost in setting up the machinery
.However ,if two types of products are to be made .It may call for two separate layouts .Doing multiple job on
the same equipment with the same. To save time is usually not the characteristic of a product layout .Each Line
layout caters only to one product.
The principles of minimum distance moved (each operation adjacent to the previous operation )and of
congruence of flow of materials and sequence of equipment , are very well satisfied in a line layout .But this can
only be true when there is only one standard product to be made ,day in and day out .If there is another type of
product to be made ,then the present line-up of equipment may not correspond with the flow of this new product
,resulting in high costs due to excessive material movement and excessive idle-times of machinery and
manpower.
So, when continuous production is possible due to high volume of production over a long run of time of a
standard product with the assurance of a continuous supply of raw material, Product layout is preferred .When
the production is of job-shop type ,each product being unique in terms of the number and type of operations to
be performed ,and the setting of the machinery required, thus involving a high degree of change with low
production volume ,Process layout is preferred .The major requirement in a job-shop type production is
flexibility:
A. product-design, and therefore machine-setting flexibility;
B. flexibility of types of processes operating or in other words, routing flexibility;
C. Flexibility regarding the number of similar items manufactured, i.e. volume flexibility.
Product layout
A simple sketch of product layout is as follows:
A
B
For each product there are different die boxes ,machines required for production process sequence. Such
machines include lathe ,grinder ,painting, milling. The assembling of each product will be done separate on the
production line beginning with receiving of raw material near the first machine. The material will then move from
machine to machine till the final product is ready in all respects.
Problem:
4. Sales forecast =72000 units of product per year. The product is manufactured through three operations
A, B, & C taking 5, 10 & 15 minutes respectively. Find out machinery requirements of operation A, B &
C.
Solution:
Total machining hours available per day= 8*250 = 2000hrs per year.
Production rate required = total production during year
Total machining hrs per day
= 72000 / 2000
= 36 units per hr
Machine output at operations A, B & C will be
A 60 min/hr = 12 pcs /hr
5 min /hr
B 60 min/hr = 6pcs /hr
10 min /hr
C 60 min /hr = 4 pcs /hr
15min/hr
STANDARD TIME PER UNIT / NUMBER OF MACHINES
OPERATION IN MINS REQUIRED
A 5.0 36 /12 = 3
B 10.0 36 / 6 =6
C 15.0 36 / 4 = 9
5. PROCESS LAYOUT:
Process layout also called “layout by function” is generally associated with batch production. The factory is
divided into process units (or departments), and within these process units (or departments) all similar facilities
are grouped together. Presses, for example, are kept at one place; milling machines are placed at another
place; drilling machines are kept at third place; gear cutting machines are located at fourth place; and so on and
so forth.
Here, the layout should provide tremendous flexibility in the sequence of operations because; the sequence
of operation for one job is different from that of another job.
Process layout is suitable when,
i. The products are non- standard, or
ii. There is a wide variation in the processing times of individual operations.
Example:
A machine shop generally has separate departments where general-purpose machines are grouped
together by function (e.g., milling, grinding, drilling, hydraulic presses, and lathes). Therefore, facilities that are
configured according to individual functions or processes have a process layout. This type of layout gives the
firm the flexibility needed to handle a variety of routes and process requirements. Services that utilize process
layouts include hospitals, banks, auto repair, libraries, and universities.
Improving process layouts involves the minimization of transportation cost, distance, or time. To accomplish
this some firms use what is known as a Muther grid, where subjective information is summarized on a grid
displaying various combinations of department, work group, or machine pairs. Each combination (pair),
represented by an intersection on the grid, is assigned a letter indicating the importance of the closeness of the
two (A = absolutely necessary; E = very important; I = important; O = ordinary importance; U = unimportant; X =
undesirable). Importance generally is based on the shared use of facilities, equipment, workers or records, work
flow, communication requirements, or safety requirements. The departments and other elements are then
assigned to clusters in order of importance.
To illustrate ,a factory in which all the products manufactured have to pass through such processes as
turning ,milling ,treating and grinding will arrange all its lathes in the turning department ,all milling machines in
the milling machine department and all grinding machines in the grinding department . Thus, in process layout,
machines of identical functions are grouped together kept in one department. These machines are used for
production purposes by workers from different skills as per their requirements. All operations of similar nature
are grouped together in the same department.
6. Lathe dept Drilling Milling Assembly dept Painting dept
Cutting dept Shaping dept Heat treatment Packing dept
Product A
Product B
Process layout for medical clinics:
Gynerology Laboratory
Neurology
tests
Restroom X -Rays
Plastic &
Reception room Patient waiting reconstruction
surgery
room
Pediatrics
Pharmacy
Patient exit clinic
7. Advantages of process layouts include:
• Flexibility. The firm has the ability to handle a variety of processing requirements.
• Cost. Sometimes, the general-purpose equipment utilized may be less costly to purchase and less costly
and easier to maintain than specialized equipment.
• Motivation. Employees in this type of layout will probably be able to perform a variety of tasks on multiple
machines, as opposed to the boredom of performing a repetitive task on an assembly line. A process
layout also allows the employer to use some type of individual incentive system.
• System protection. Since there are multiple machines available, process layouts are not particularly
vulnerable to equipment failures.
Disadvantages of process layouts include:
• Utilization. Equipment utilization rates in process layout are frequently very low, because machine usage
is dependent upon a variety of output requirements.
• Cost. If batch processing is used, in-process inventory costs could be high. Lower volume means higher
per-unit costs. More specialized attention is necessary for both products and customers. Setups are more
frequent, hence higher setup costs. Material handling is slower and more inefficient. The span of
supervision is small due to job complexities (routing, setups, etc.), so supervisory costs are higher.
Additionally, in this type of layout accounting, inventory control, and purchasing usually are highly
involved.
• Confusion. Constantly changing schedules and routings make juggling process requirements more
difficult.
PROBLEM:
Data for certain operation of 3 products to be carried out on one type of machine is as follows
8. TIME IN MINUTES
Sales forecast per No. of setups per
week wk
product Setting up machining
A 1200 15.0 1.00 1
B 2000 30.0 0.45 2
C 4000
45.5 0.30 3
FIND OUT NUMBER OF MACHINES REQUIRED.
SOLUTION :
Total setup time per week =Setup time in mins * no .of setups /week
60mins/hr
Product A 15 * 1 / 60 = 0.25 hrs /week
Product B 30 * 2 /60 =1.00 hr / week
Product C 45 *4 /60 =3.00 hr /week
Production time / week = std time /unit *prodn rate
60 min /hr
Product A 1 * 1200 /60 = 20hrs /week
PRODUCT B 2000 *0.45 /60 = 15 hrs /wk
PRODUCT C 4000 * 0.30 /60 = 20 hrs / wk
Therefore, total machine hrs required = setting up line per week + prodn time per week.
= ( 0.25 ) (20.0)
+( 1.00) + (15.0)
+ ( 3.00) (20.0)
(4.25) (55.0)
= 59.25 hrs /wk (on the basis one shift working)
Therefore, machine hrs available per week = 6 * 8 = 48 hrs
Therefore, no. of machines required = 2
9. Comparison between product layout & process layout
The relative characteristics of product & process layout are:
1. MACHINE UTILIZATION:
In the process layout, similar machines or processes being grouped together, machine utilization is
higher.
In the product layout, even the machine is utilized for 10% of time; it must be installed to perform
operations on same type of product. In some other division of the company manufacturing similar product
may have same machine utilized for 20% of time but that second machine is also required at its position
to cater the needs of that second product. Thus, the overall machine utilization is lesser in product layout.
2. PLANT INVESTMENT:
Product layout requires higher initial investment than process layout as special purpose machines
are costly and at times require to be duplicated to balance the production line.
3. TYPE OF MACHINES USED:
Since same machines are used for different products, a general purpose machine can be used for
process layout. However, since only one type of product is manufactured on machines in product
layout, a special type of machine is used
4. REQUIREMENT OF SPACE :
Process layout requires comparatively more space than product layout since additional space is
required to
• Keep the jobs which queue up before each machine.
• Accumulate jobs until they are moved to next work station.
This is because unlike in product layout material flow is discontinuous.
5. MANUFACTURING TIME :
10. Under the process layout, it takes comparatively more time in manufacturing goods. Higher
manufacturing time results on account of formation of queues at different machines due to different
cycle times, batch sizes and sequence of operations.
Manufacturing cycle time under product layout is small since machine capacities are balanced
and intermediate activities like travel, storage and inspection are reduced. Product for continuous or
process production may be looked upon as one large machine wherein raw materials enter at one end
and emerge as finished product at other end.
6. MATERIAL HANDLING :
Process type of layout results in more handling than the product type of layout because:
• Flow of materials between different stages of manufacture is highly discontinuous due to imbalance in
operation wise work content while flow of material in a product layout is continuous and there is little or
no queuing at any stage of processing
• Distance between the departments in process layout is large which increases transport distance and
raises the cost of materials handling. On the contrary, in the product layout materials move through a
short distance between stages.
• Materials, components and parts in a process layout are handled either singly or are placed in trolleys
or in bins and are transported as unit loads by fork lift trucks. Material handling in a product is highly
mechanized. Conveyor system and automatic transfer machines move materials from one stage to
another.
7. FLEXIBILITY:
• Process layout offers a very high flexibility as alterations in operation sequence can be made when
they are required. Also, new jobs, each having different routine than other and varying work
content can be taken up without difficult.
• However, such flexibility does not exist in a product layout. Only jobs having the same routing and
equal work content can be accommodated. It is also rather difficult to adjust proportionately in
accordance with the change in demand.
8. ADAPTIBILITY DUE TO BREAKDOWN /SHORTAGESETC:
• Process layout offers flexibility in production schedules since disturbances due to machine breakdown,
absenteeism of key operators and non-availability of raw materials do not seriously affect production
as another machine can be taken up.
• Flexibility in production schedules in case of product layout is seriously affected due to interruptions
due to breakdowns & absenteeism as stoppage of one machine usually disturbs the working of other
machines. Storage of materials also affects the production line. “Systematic maintenance “and
“provisioning of standby operators “are therefore two major management functions.
11. 9. IN PROCESS INVENTORY:
Since the parts or materials of a product have to wait for their turn to get processed in case of process
layout, the in process inventory is relatively higher. However, in case of product layout, same product is
processed on all machines, waiting time at every location is less and thus in process inventory is less.
10. LABOUR TRAINING :
As the type of product is manufactured on any machine is the same in the product layout, training of
labour force is easier and cheaper in this case.
11. LABOUR UTILIZATION: since machine utilization is higher in process layout, therefore labour utilization is
also higher.