Plant Layout

Definition & Objectives

Planning the optimum arrangement of facilities, personnel, equipment, storage space, material handling equipment and all supporting services, along with the design of the best structure to contain all these facilities

Economic handling of all material; better supervision; faster production; better product quality; flexible plant & workspace design for expansion; Improved work conditions; unidirectional workflow

Activities Classification

Office area

Plant area

Production department

Services department
Technical services
Personal services

Technical services
Receiving department
Store room
Stock room
Tool room
Inspection department
Power house
Material handling
Shipping department

Personal services
Parking area
Timekeeper office
Canteen & lunch room
Recreation room
toilets

THE NEED FOR GOOD FACILITIES PLANNING

1. Plant facilities influence operating costs and profits.
2. Planning allows facilities and its operations (ISO 14001, etc.) to comply with laws and/or regulations.
3. Facilities are fixed investments involving high capital-cost expenditures.
4. Facilities are inflexible and long term commitments.
5. The planning, design and construction of facilities require long lead times.
6. Good planning helps to avoid disruptions in production and shipping or delivery.

Ideal plant layout

Acc to F. G. Moore
“A Good plant layout is one which allows material rapidly & directly for processing . This reduces transport handling, clerical and other costs down per unit , space requirement are minimised and it reduces idle machine and idle man time”

Advantages

Better working conditions for workers
Minimization in material handling
Minimization in damage & spoilage
Minimization of congestion of material, machinery, workers
Flexibility to adapt to changing production conditions

Objectives of an ideal layout
Minimization of material handling
Elimination of bottle necks
High material turn over
Effective utilization of cubic space
Effective utilization of man power resources
Elimination of physical efforts required operative workers

Factor affecting
Type of production
Production system
Scale of production
Types of machines
Types of building facilities
Availability of total floor area
Possibility of future expansion

Material Flow system
Men , Money , Machines
Men & machine static
Material moves
Minimizing flow of material
Flow pattern helps in eliminating bottlenecks
Minimizing material handling cost

Material flow system
Horizontal flow system
Vertical flow system

Horizontal flow system
I type flow
L types flow
U types flow
S type flow
O types flow
I & U combination
I & S combination
I & O combination

I & L flow
Shortest route
Must have roads on both sides
Pant area has long length & short width
Difficulty in returning empty container
Absence of rushing of outside transportation
Unsuitable for longer product lines

U type flow
One side road link will be required
Less difficulty in returning the empty containers
Possibility of rushing of outside transportation
Suitable for longer production line
Requires square floor area

S type system
Requires roads on both sides
Absence of rushing of outside transportation
Requires square floor area
Difficulty in returning empty container
Suitable for longer production line

O type
One side road link will be required
Heavy rush of outside transportation
Ease in returning empty containers
Requires square floor area
Suitable for longer production line

Types
Process layout
Product layout
Combined layout
Project layout
Cellular layout
Job shop layout

Process layout
similar equipment & tasks grouped; also called functional layout; useful for low volume, high variety jobs
used when small batches of different products are created or worked on in a different operating sequence

Characteristicsof Process Layouts
Low Volume, High Variety Production with Random Routing (Spaghetti-Like Flow)
General Purpose Machines--
Machine setups are frequent and long
Work-In-Process -- High
Throughput Rates tend to be Low
Material Handling -- High
Operator Utilization -- Low?
Throughput Times (Lead Time) -- High
System is Very Flexible, produces many different types of parts: gears, shafts, pinions, housings, clamps, etc.

Process(Functional) Layout
Advantages
low capital investment,
fewer m/c;
higher space utilisation;
flexibility in equipment allocation;
workers gain expertise;
problems localised;
job variety

Disadvantages:
needs more space;
no mechanisation;
high wip;
work scheduling problems;
high set-up
inspection costs

Product Layout
Equipment placed in usage sequence; also called line layout; useful in assembly work such as cars, m/cycle
The product layout (assembly line) is used when all products undergo the same operations in the same sequence

CHARACTERISTICS
High volume production
Special purpose machines and material handling equipment
Throughput rates--high
Work-in-process--low
Setup/Run time ratio--low
System is very inflexible
Control is relatively simple

Product Layout

Advantages
Small mfg cycle;
low wip;
min material handling;
lower labour cost;
effective quality control;
easy to schedule;
easy prodn control;
low variety

Disadvantages
Change in work nature needs change in layout;
m/c utilisation may not be optimum;
m/c breakdown delays work;
work area expansion/m/c addition not possible

Project Layout
Raw material placed in fixed positions; also called fixed position layout

Advantages
Reduces movement of m/c & equipment;
Minimizes damage/cost of movement;
continuity of assigned work force

Disadvantages:
Skilled & versatile workers needed due to multiple operations;
skill combination may be difficult to obtain;
higher pay;
nmovement of people/material may be expensive;
equipment utilization low as they are left at location for subsequent usage instead of being moved as & where needed