Formation techniques When we manufacture plastic objects in industry, the plastic is available in three different forms, powder, granules and resins. We use different formation techniques depending on the type and use of plastic. Extursion: This technique has four stages: 1.We put thermoplastic,in granular form,into a previously heated cylinder. 2.We apply pressure by means of a large,rotating screw,which forces the melted material out,throug a nozzle. 3.We cool the shaped material slowly in a refrigerated water bath until it is solid. 4.Finally,we collect the pieces of plastics through a feeder system.