PRODUCTION MANAGEMENT

LECTURE –III & IV

• The Production Function• Types of production system• Elementary knowledge of manufacturing processes

• Plant Layouts• Material Handling• Location Problems• Inventory management• Scheduling

• Network Analysis• Break Even Point Analysis• Reliability maintenance & plant services• Quality control• Emerging Trends

• Concept of Productivity

Syllabus

• Plant Layouts :

• Objectives

• Symptoms Of Poor Layout

• Types Of Layout

• Functional Layout

• Line Layout

• Static Product Layout

• Group Layout

• Factors Influencing Layouts

• Plant Layout Tools & Techniques

CHAPTER -III

PRODUCTION SYSTEM

CONVERSION PROCESSINPUT OUTPUT

CONTROL

DECISION MAKER

IN OUT

Definitions of plant layout :

A method of organizing the elements of a production process, in

which similar processes and functions are grouped together

Plant Layout is the physical arrangement of equipment and facilities within a Plant

Plant layout is the organization of physical facilities like machinery ,

equipment & the allocation of space for the various activities of the

plant & personnel working in the plant

PLAN LAYOUT

To improve productivity, safety and quality of Products

Unnecessary efforts of materials handling can be avoided when the

Plant Layout is optimized

This is valid for :

- Distances Material has to move

- Distances Equipment has to move

- Distances Operators have to move

- Types of Handling Equipment needed

- Energy required to move items against resistance (i.e. gravity)

Optimizing the Layout of a Plant

Provide space for machine / materials / storage / etc

•Flexible for future changes in capacity / Design / Process etc

( Cellular design)

• Accommodate future expansion

•Comply with government rules & regulations ( Municipal corporation /

Labor law & rules

• Safety of employees / visitors / vendors is prime concern

• Achieve economy in operation

Plant Layout Characteristics :

Building & Structure :Depend on type of production system ( Intermittent / Continuous)Intermittent System : Building & Shades are constructed & layouts done in shades with best possible options & then machinery will be brought inside

Continuous System : Arrange machines first then construction around . It should withstand & offer support to cranes / hoists / trolleys etc.

The floor should be designed considering the load it should carry ( Tons / Sq m)

Men :

• Number of people

• Unskilled ( More space ) / Skilled ( Less space i.e. Computer operator)

• Physic of workers ( ex. height )

Receiving Grin-

Mills ders

Raw matl. Large number of

storage Assem- low volume

bly products

Drills

Planers

Finished

Inspec- goods

Lathes Automatics tion storage

Part A

Part B

Intermittent System

Stage 1 Stage 2Machine

XMachine Y Machine Z

Raw Material

Finished Product

Continuous System

: Type of machine :

• General purpose machines : Compact in size & requires less

space

• Special Purpose machines (SPM) : Large in size ,

complicated , high level of automation

• Number of machines :

• Level of automation ( Semi / fully automated)

• Higher complexity wider space

• Level & frequency of maintenance

Machine

• Nature of material ( Flammable / inflammable / Hazardous & Non

Hazardous , Corrosive , Methalene , mercury , oils , fuels)

• Form of material ( Solid / Liquid / Powder etc)

• Quantity of material to be handled

• Cycle Time : Consumption of material

• Availability of material

•

Materials :

Movement :

• Movement of people / machines / cranes ( length & frequency)

• Purpose of movement ( With load / without load / Quantity of load)

Waiting Time :

• Cycle time for completeting each activity

• Intermittent –

•Uncertain & High

• More storage places between machines & facilities

• Continuous –

•Defined & low

• Purpose of waiting

• Process ( low space)

• Idling (More space)

Changes :

• Production Volume

• Product type & design

• Process type

• Varieties

• Frequency of change ( Ex 5 years)

Services

• Electrical supply

• Pneumatic supply ( Air supply)

• Water supply

• Chilling process – Cooling Tower

• Air ventilation –Ducting

• Fire extinguishers – Water sprinklers

•Plant layout begins with plant location and continues through 3 further levels,

1. Layout of department within site

2. Layout of items within the department

3. Layout of individual work places

•

Plant Layout

Symptoms Of Poor Layout

A good layout results in

• Comfort, • Convenience, • Safety, • Efficiency, • Compactness And • Finally In Profits To The Organization

A poor layout results in

• Congestion,

• Wastes,

• Frustration,

• Inefficiency And

• Finally A Lower Profit Or A Loss To An Organization

Types Of Layout

Functional Layout ( Process Layout

Line Layout ( Product Layout)

Static Product Layout ( Fixed Position)

Group Layout ( Cellular Layout)

Combination layout ( Hybrid Layout)

Functional Layout ( Process Layout)

• Also called as process layout

• Its best suited for intermittent type of operation

• Machines on layout are called as general purpose machines

• It involves a grouping together of like machines in one section / dept

Example :

• Machines performing grinding operation are installed in grinding dept

• Machines performing drilling operation are installed in drilling dept

• Heat Treatment / Painting etc

Receiving Grin-

Mills ders

Raw matl. Large number of

storage Assem- low volume

bly products

Drills

Planers

Finished

Inspec- goods

Lathes Automatics tion storage

Part A

Part B

Machine shop Functional Layout ( Process Layout)

Functional Layout ( Process Layout)

Advantages :

• Greater flexibility in production

• Easy to handle M/c breakdown by transfer of to another machine

• Greater Scope for expansion

• Investment on equipment will be comparatively low

• Full utilization of equipment

• Greater incentive to operators to improve performance

Disadvantages :

• Accumulation of work in progress

• Requires more floor space

• Difficulty in movement of material

• Production control is difficult

• High production time as WIP has to travel from place to place

• It involves the arrangement of machines in one line , depending on operation

sequence

• Raw material will be fed in first machine & final product will come out of last machine

• Output of one machine becomes input to next machine

Example :

• Sugar refineries / Paper mills / Cement plants / Rolling mills / paper mills

Line Layout ( Product Layout)

Stage 1 Stage 2Machine X Machine Y Machine Z

Raw Material

Finished Product

Advantages :

• Smooth & regular flow of finished goods

• Shorter processing time due to less travel , storage & inspection frequency

• Reduced material handling

• Low cost labors & lesser training requirement

•Use of special purpose machines (SPM) ,automatic or semi automatic

• Less floor are with high productivity

• Easy production control

Disadvantages :

• Heavy capital investment

• Non flexible layout

• Risk of total production line shutdown

• Supervision is more difficult

Line Layout ( Product Layout)

Static Layout ( Fixed Position Layout)

This type of layout involves the movement of men & machines to the product Which remains stationary

1. Aircraft Assembly

2. Flyover Bridge

3. Water Dam

Raw Material

Machine & equipment

Labors

Finished Product

Advantages :

• Men & machine can be used for wide variety of operations producing different products

• The investment on layout is very small

• The high cost of & difficulty in transporting a bulky product are avoided

Disadvantages :

• High cost of operation

• Very high duration of project

• Rework will be very costly

Static Layout ( Fixed Position Layout)

In cellular manufacturing layout the arrangement of a facility so that

equipment Used to make similar parts or families of parts is grouped

together

The group of equipment is called “ cell “

The arrangement of cells is called a “ cellular Layout “

1

5

2

4

3

1

Cell 1211 3 Cell 3

Cell 2 Cell 4

Group Layout ( Cellular Layout)

It is a combination of product & process layout with an emphasis on either

In industries plants are never laid out in either pure form

It is possible to have both types of layouts in an efficient combine form if the products are somewhat similar & not complex

Fabrication of parts ----Process Layout Assembly of parts ----Product layout

Ex : Soap Manufacturing Machines ---- Product line Process Layout ---------- Functional basis---Ancillary services ---- Heating / Manu of glycerin / power house / water treatment plant

Combined Layout ( Hybrid Layout)

F.P

F.P

G.C

G.C

G.C

H.T

H.T

G.G

G.G

Process Layout

Product Layout

Raw material

Raw material

Finished Products (Gears)

F.P : Forging Press G.C : Gear Cutting H.T : Heat Treatment G.G : Gear Grinding Machine

Line Balancing

Line balancing is the phase of assembly line study that

equally divides the work to be done among the workers so

that the total number of employees Required on assembly

line are minimized & no employee of equipment will remain

idle.

Factors Influencing Layouts1.Factory Building : The nature & size of building determines the floor space available

for layout

While designing the special requirements i.e. Air conditioning , dust control , Humidity control ,Noise proofing etc must be kept in mind

2. Nature of product : Product layout is suitable for uniform products

Process layout is suitable for custom made products

3. Production process : In assembly line industries product layout is better.

In job order or intermittent manufacturing process layout is desirable

4.Types of machinery : General purpose machines are arranged as per process layout , Special purpose machines are arranged as per product layout

5. Repairs & Maintenance : Machines / Equipments must be arranged keeping in mind the movement of operators & maintenance tools

6. Human Needs : Adequate arrangement should be made for Wash rooms, drinking water / Canteen & other employee facilities

7.Plant Environment : Heat / Noise / Light / Ventilation & other aspects should be duly considered e.g. Paint shop / Fabrication / Plating section should be located separately to protect employees from harmful fumes etc. Adequate safety arrangement should be made

• The plant layout should be conducive to health & safety of

employees

• It should ensure free & efficient flow of employees & materials

• Future expansion & diversification may also be considered while

planning factory layout

To conclude

Factors Influencing Layouts

Plant Layout Tools & Techniques

1. Process Chart

i. Operations process chart

ii. Flow process chart

2. Process Flow Diagrams

3. Machine Data cards

4. Visualization of layout

i. Two dimensional plan or template

ii. Three dimensional plan or machine models

Process Chart : It is a classification & graphic representation of production activities in a plant

Very useful for systematic analysis of various operations & material movements in

production process & there effectiveness

Study helps to identify operations that can be eliminated / rearranged / or simplified to

achieve economy in production

Operation Process Chart :

Flow Process Chart :

It is graphic representation of all the activities occurring on the floor of the plant

This chart accumulates & classifies the complete information necessary for the analysis

& improvement of plant operations .

Plant Layout Tools & Techniques

Plant Layout Tools & Techniques

2. Process Flow Diagram : It helps to visualize the movement of material on an existing floor layoutHelps in identifying excessive movement of materials & helps in relocationsof plant activities to reduce travel distance

3.Machine Data Cards : This is an effective method to provide necessaryinformation for placement Or layout of the equipmentThe cards indicates machines capacity / space & power requirements , handling

needs & corresponding dimensions 4.Visualisation of Layout :Most common method of planning a layout by making replicas of machines ,racks , benches , & equipment & then arranging these on a

2d /3d plan of the floor space

i) Two Dimensional Plan (Template)

ii) Three Dimensional plan ( Miniature models )

SUMMARY

Decisions about layout are made only periodically. As they have long term consequences ,they must be made with careful planning .The layout design affects the cost of producing goods & delivering services for many years in future. Here we have discussed three “Traditional “ Basic layouts: 1) Process 2) Product 3) Fixed Position.Process Layout arrange work centers according to function.Product Layouts ( Assembly layout) arrange work centers & equipments in line to perform specialized sequence of tasks.In Fixed position Layout ,the product remains in one location & resources are brought to it.

In process & product layouts , the design begin with a statement of goals of facility. The layouts are designed to meet these goals. After initial designs have been developed , improved designs are sought which will be cumbersome ,hence to take care of it quantitative & computer based models are used.