In plastic Industries three main processes were known to the industries (1) Extrusion (2) Blow Moulding (3) Injection Moulding. In all these processes the main draw back is the tooling or die cost of the equipment against the single piece weight of the product. For the large Hollow component the Rotational Moulding is most economical process. The basic advantages of the process are as below.

• Economic tooling costs, 

• One-piece construction, 

• Weight reduction as compared to most metals,

• Uniform wall thickness

• Variety of finishes and colours,

• The ability to produce multi-wall Mouldings,

• Metal inserts as integral parts.

• Minor undercuts are possible with no draft angle required,

• Short lead-time, 

• Products from this process can offer excellent load-bearing properties and resistance to    

   stress cracking and corrosion.