Types of Plastic Manufacturing Methods

Plastic has become a part of our daily lives. We have plastic items everywhere we look around us. Ever wondered where all this plastic comes from? If you just answered plastic manufacturers, then you are right. The real question everyone wonders about is how are various items fabricated and which methods are used by plastic manufacturers. Here is all you need to know to satisfy your curious brain cells.

The secret of the manufacturing technique used by the plastic manufacturers lies in the number of replicas of that particular product are to be manufactured. Some processes are manual while some involve high tooling investment. Manual methods are crafting based and thus are slower than the ones that involve a lot of tools is faster and efficient. But the tools are costly and thus such processes involving complex tooling are only used for manufacturing bulk products. Processes like casting, fabrication, and rotational moulding are low costing processes and are used by small scale plastic manufacturers and processes like injection moulding are used by large scale plastic manufacturers.

Certain plastics are used only with certain processes and that is another way to identify the type of plastic. If you know the process of manufacturing used by the plastic manufacturers, it is easy to ascertain the type of plastic of the product. For example, thermoplastics are never manufactured by thermoforming or injection processes. Also, some processes leave marks on the finished products. To be clear, there are two kinds of marks left on the finished products - the first type are the marks that are left by the ‘sprue’ which is the tail of plastic that is broken off at the point it enters the mould and the second type of marks are the ejector pin marks which are smooth and circular and are created while the removal of the moulding from the mould.

Plastic Manufacturers

There are 8 types of plastic moulding methods used by plastic manufacturers:

#1. Blow Moulding: This process uses a hot air blow and thus the name. Hot air is blown into a tube of semi-molten plastic which expands due to the hot air into a two-part metal mould.

#2. Casting: This is a simple proces It involves adding molten plastic directly into the mould and the mould itself is moulded from plastic. This process has low tooling cost. It is used for products with predefined standard shapes like tubes, rods, jewellery, paperweights, etc.

#3. Compression Moulding: This method is a little more complicated than the casting process. It involved taking a measured amount of molten plastic in a two-part mould and then subjected to heat along with pressure.

Moulding

#4. Extrusion: This involves plastic pellets fed into a heated cylinder and moulded by driving forward those pellets using a driving screw and compacting and melting them and thereby creating profile with a continuous lengths and shapes.

#5. Fabrication: This is a process involves a lot of manual work. Processes like bonding, carving, cutting, sticking, turning, and welding are included under this process. Rach plastic manufacturer has a different approach while using this process based on the product and the craftsmanship required.

#6. Foaming: This is the method extensively used to make containers. The process basically involves release of gas or air into the plastic so that it fills with bubbles and foams within a two part metal mould.

#7. Injection Moulding: Plastic is injected into the metal mould. This involves pressurised injection that enables to inject plastic in even moulds with a lot of branching as well as multi-impression tools.

#8. Rotational Moulding: A measured amount of semi-molten plastic is placed between 2 axes and rotated. The molten plastic covers the surface and adheres the shape of the mould.

These processes are not as simple as they sound. Plastic manufacturers need to be skilled craftsman to manufacture quality plastic products with flaws.