subject: Compression Moulding And Its Advantages [print this page] One of the many plastic manufacturing methods conducted at plastic factories is compression moulding. Thermosetting plastics (plastics which cannot be reheated and remoulded once set) are the plastics that are used in compression moulding, either in resin/granule or putty pre-form states.
This is a method of producing a solid plastic after placing the heated raw material in an open cast. Once the cast is filled, it is closed and an intense pressure is applied and maintained until the plastic has set. It is then left to cool slowly and solidify
This is a very common method of producing plastics with very specific properties. For example, this is a method typically used to produce high strength, reinforced plastics. This form of plastic manufacture was created to produce replacement material for metals. Therefore the end product must be robust and incredibly strong. The compression moulding process is also a very cost effective method as, like casting methods, it wastes very little raw plastic resin. Due to the nature of the plastics strength it is often used in construction and therefore the plastic companies generally produce this material in large sheets, films and curved structures. To increase the strength of these plastics, additives are often added, for example formaldehyde, melamine and urea as well as certain metals.
There are many advantages to using compression moulding during production; for example, the plastic can be measured exactly before being placed into the heated mould. As the resin begins in a soft solid state (rather than liquefied) the manufacturer can ensure that only the required amount of resin is selected preventing large amounts of waste as in some production methods. Another reason compression moulding is so useful is that it is a relatively easy method. There are no gates or rollers or dies that the plastic must move through before reaching the mould and therefore this, again, prevents the loss of material through spillages or leaks etc allowing all the raw resin to be used. As this is a fairly simple process to carry out it also reduced the need for heavy machinery and a large workforce, again reducing costs to the manufacturer and reducing the overheads for the company.
Plastics which have be produced using this method include large panels for vehicles, electrical parts and covers, ash trays and sports equipment.
Alongside the compression moulding method, plastic companies also employ a range of techniques to create plastic products. You can find more information if you visit the Ensinger website.
