Methods and Type of Areas of Plant Layout23/02/2020
Methods of plant layout
- Process chart
It is a graph containing details regarding various activities and operations taking place in the organization from start to the last stage of the work.
- Process flow diagram
This is an aid to process chart. This relates to details regarding position of machines, area covered by each machine, internal transportation and other operations pertaining to production. This model diagram is prepared on the paper.
The area covered by a machine is cut to scale from a thick paper to form a template. Not only machines but space covered by furniture, equipment and other components can also form a template. These can be well arranged representing the actual plan of layout to be undertaken.
Three dimensional wooden models of machinery, equipment and other devices and components can be prepared. By seeing these models even a layman can form an idea about the layout of the plant. But this technique is very costly and only big concern can afford to install such a measure.
Layout drawings can be got prepared by drafts men showing walls, stairways, machines and equipment etc.
- Machine data card
These cards are tied with different machines operating in the plant. These obtain valuable information regarding various salient features or characteristics of machines viz., efficiency, capacity space area covered by the machine and technique of operating the machine etc.
TYPES OF PLANT LAYOUT
Four Main Types of Plant Layout
Product or Line Layout
If all the processing equipment and machines are arranged according to the sequence of operations of the product, the layout is called product type of layout. In this type of layout, only one product of one type of products is produced in an operating area. This product must be standardized and produced in large quantities in order to justify the product layout.
The raw material is supplied at one end of the line and goes from one operation to the next quite rapidly with a minimum work in process, storage and material handling. Fig. 1 shows product layout for two types of products A and B.
Advantages offered by Product Layout
(i) Lowers total material handling cost
(ii) There is less work in processes
(iii) Better utilization of men and machines
(iv) Less floor area is occupied by material in transit and for temporary storages
(v) Greater simplicity of production control
(vi) Total production time is also minimized
Limitations of Product Layout
(i) No flexibility which is generally required is obtained in this layout
(ii) The manufacturing cost increases with a fall in volume of production
(iii) If one or two lines are running light, there is a considerable machine idleness
(iv) A single machine break down may shut down the whole production line
(v) Specialized and strict supervision is essential
Process or Functional Layout
The process layout is particularly useful where low volume of production is needed. If the products are not standardized, the process layout is more low desirable, because it has creator process flexibility than other. In this type of layout, the machines and not arranged according to the sequence of operations but are arranged according to the nature or type of the operations. This layout is commonly suitable for non repetitive jobs.
Same type of operation facilities are grouped together such as lathes will be placed at one place, all the drill machines are at another place and so on. See Fig. 8.4 for process layout. Therefore, the process carried out in that area is according to the machine available in that area.
Advantages of Process Layout
(i) There will be less duplication of machines. Thus, total investment in equipment purchase will be reduced.
(ii) It offers better and more efficient supervision through specialization at various levels.
(iii) There is a greater flexibility in equipment and man power thus load distribution is easily controlled.
(iv) Better utilization of equipment available is possible.
(v) Break down of equipment can be easily handled by transferring work to another machine/work station.
(vi) There will be better control of complicated or precision processes, especially where much inspection is required.
Limitations of Process Layout
(i) There are long material flow lines and hence the expensive handling is required.
(ii) Total production cycle time is more owing to long distances and waiting at various points.
(iii) Since more work is in queue and waiting for further operation hence bottle necks occur.
(iv) Generally, more floor area is required.
(v) Since work does not flow through definite lines, counting and scheduling is more tedious.
(vi) Specialization creates monotony and there will be difficult for the laid workers to find job in other industries.
Fixed Position Layout
This type of layout is the least important for today’s manufacturing industries. In this type of layout the major component remain in a fixed location, other materials, parts, tools, machinery, man power and other supporting equipment’s are brought to this location.
The major component or body of the product remain in a fixed position because it is too heavy or too big and as such it is economical and convenient to bring the necessary tools and equipment’s to work place along with the man power. This type of layout is used in the manufacture of boilers, hydraulic and steam turbines and ships etc.
Advantages Offered by Fixed Position Layout
(i) Material movement is reduced
(ii) Capital investment is minimized.
(iii) The task is usually done by gang of operators, hence continuity of operations is ensured
(iv) Production centers are independent of each other. Hence, effective planning and loading can be made. Thus total production cost will be reduced.
(v) It offers greater flexibility and allows change in product design, product mix and production volume.
Limitations of Fixed Position Layout
(i) Highly skilled man power is required.
(ii) Movement of machines equipment’s to production centre may be time consuming.
(iii) Complicated fixtures may be required for positioning of jobs and tools. This may increase the cost of production.
Combination Type of Layout
Now a days in pure state any one form of layouts discussed above is rarely found. Therefore, generally the layouts used in industries are the compromise of the above mentioned layouts. Every layout has got certain advantages and limitations. Therefore, industries would to like use any type of layout as such.
Flexibility is a very important factory, so layout should be such which can be molded according to the requirements of industry, without much investment. If the good features of all types of layouts are connected, a compromise solution can be obtained which will be more economical and flexible.