Plant layout study

A plant layout study is an engineering study used to analyze different physical configurations for a manufacturing plant. It is also known as Facilities Planning and Layout.

Introduction

The ability to design and operate manufacturing facilities that can quickly and effectively adapt to changing technological and market requirements is becoming increasingly important to the success of any manufacturing organization. In the face of shorter product life cycles, higher product variety, increasingly unpredictable demand, and shorter delivery times, manufacturing facilities dedicated to a single product line cannot be cost effective any longer. Investment efficiency now requires that manufacturing facilities be able to shift quickly from one product line to another without major retooling, resource reconfiguration, or replacement of equipment.

Investment efficiency also requires that manufacturing facilities be able to simultaneously make several products so that smaller volume products can be combined in a single facility and that fluctuations in product mixes and volumes can be more easily accommodated. In short, manufacturing facilities must be able to exhibit high levels of flexibility and robustness despite significant changes in their operating requirements.

In industry sectors, it is important to manufacture the products which have good quality and meet customers’ demand. This action could be conducted under existing resources such as employees, machines and other facilities. However, plant layout improvement, could be one of the tools to response to increasing industrial productivity. Plant layout design has become a fundamental basis of today’s industrial plants which can influence parts of work efficiency. It is needed to appropriately plan and position employees, materials, machines, equipment, and other manufacturing supports and facilities to create the most effective plant layout.

OBJECTIVES OF PLANT LAYOUT :

1. To ensure economical utilization of all the resources. 2. To ensure smooth flow of material. 3. To provide sufficient flexibility. 4. To ensure good working condition which will result in better safety of workers and will provide hygienic environment. 5. To minimise the industrial waste. 6. To improve plant productivity.

Types of plant layout

Broadly the plant layout is classified into four categories:

1.Line layout/product layout

In line layout the machines are arranged according to the sequence of operation to be performed, in a single line.

Basic features of line layout are:

Used for mass production

Same type of product are designed

Having poor flexibility

2. Process layout/functional layout

The machines which are performing same types of function are arranged in a particular group at one specific location.

These machines are grouped according to their function/ operation

Features of process layout:

Provide product variety

Flexibility

Used for batch production

Generally used in engineering workshops

Limitations:

Increases lead time due to backtracking of material.

Throughput time increase

Material handling can not be mechanised

3. Fixed layout

In fixed layout all the facilities or machines will move at the workpiece position and the workpiece remains stationary.

This type of layout is generally used for one or few very heavy products to be manufactured because the transportation cost of moving heavy products are very high.

Features:

Helps in upgrading the skills of operators and job enlargement

Provide greater flexibility

4. Hybrid layout

A combination of all the above explained layouts form the hybrid layout. It used in industries where no single type of layout fits.

(Ref: Mr. Hitesh sharma , NITUK)

Product Considerations

The intended products to be manufactured influence the choice of layout.

Further reading

1. Ang, C. L. and P. C. T. Willey, "A Comparative Study of the Performance of Pure and Hybrid Group Technology Manufacturing Systems Using Computer Simulation Techniques," International Journal of Production Research, 22, 2, 193-233, 1984.
2. Benjaafar, S., "Machine Sharing in Cellular Manufacturing Systems," Planning, Design, and Analysis of Cellular Manufacturing Systems, A. K. Kamrani, H. R. Parasei and D. H. Liles (Editors), Elsevier Science B. V., 1995.
3. Benjaafar, S. and R. Ramakrishnan, "Modeling, Measurement, and Evaluation of Sequencing Flexibility in Manufacturing Systems," International Journal of Production Research, 34, 5, 1195-1220, 1996.
4. Benjaafar, S., A. Soewito and M. Sheikhzadeh, "Performance Evaluation and Analysis of Distributed Plant Layouts," Working Paper, Department of Mechanical Engineering, University of Minnesota, Minneapolis, 1995.
5. Bozer, Y. A. and R. D. Meller, "A Reexamination of the Distance-Based Facility Layout Problem," to appear in IIE Transactions.
6. Bullington, S. F. and D. B. Webster, "Evaluating the Flexibility of Facilities Layouts Using Estimated Relayout Costs," Proceedings of the IXth International Conference on Production Research, 2230-2236, 1987.
7. Cooper, L., "Location-Allocation Problems," Operations Research, 11, 2, 331-344, 1963. # Drolet, J. R., "Scheduling Virtual Cellular Manufacturing Systems," Ph.D. Thesis, School of Industrial Engineering, Purdue University, West Lafayette, Indiana, 1989.
8. Francis, R. L. and J. A. White, Facility Layout and Location: An Analytical Approach, Prentice Hall, 2/E, Englewood Cliffs, NJ, 1993.
9. Flynn, B. B. and F. R. Jacobs, "A Simulation Comparison of Group Technology with Traditional Job Shop Manufacturing," International Journal of Production Research, 24, 5, 1171-1192, 1986.
10. Gupta, R. M., "Flexibility in Layouts: A Simulation Approach," Material Flow, 3, 243-250, 1986.
11. Kouvelis, P., A. A. Kurawarwala and G. J. Gutierrez, "Algorithms for Robust Single and Multiple Period Layout Planning for Manufacturing Systems," European Journal of Operational Research, 63, 287-303, 1992.
12. Kusiak A. and S. S. Heragu, "The Facility Layout Problem," European Journal of Operational Research, 27, 229-251, 1987.
13. Law, A. and D. Kelton, Simulation Modeling and Analysis, 2/E, McGraw-Hill, New York,