Plastic is a very versatile material and it’s finding uses in all areas of our lives. Many of us don’t even appreciate fully how much we benefit from this invention nowadays, but there are people among us with a very real appreciation for plastic’s benefits and flexible applications. If you’ve ever done a DYI project that required some specifically molded parts, for example, you’ve likely come to appreciate the usefulness of plastic quite a lot.

What is  plastic injection moulding:

Plastic injection moulding is the method of manufacturing parts made of thermoplastic and thermosetting plastic by melting and forcing into moulds where they cool to form the desired object.

How does plastic injection moulding work?

The process of plastic injection moulding usually begins with an industrial designer or engineer who designs a product. This is followed up by the work of a toolmaker or mould maker who makes the mould to fit the design created. These moulds are metallic and usually made using either steel or aluminum. Using machines, they are made to acquire the exact shape desired by the design. Once this is done, the process of actually making the plastic follows. This involves thermoplastic and thermosetting plastic being fed into a heated barrel and mixed. This melted material is then forced into the cavity of a mould and there it cools and hardens to form the desired part.

Some characteristics of the process:

  1. It uses melted and mixed thermoplastic or thermoset plastic as the base
  2. It uses a plunger which acts like a screw or a ram to force the melted material in the mould
  3. It makes a shape that is open-ended and has taken the shape of the cavity of the mould
  4. It shows a parting line and gate marks on the finished products and the ejector pin marks can also usually be made out

Plastic injection moulding design process and tooling

The process used to convert raw materials into usable plastics is called injection moulding. This process is used to manufacture products/parts from both thermoplastic and thermosetting plastic materials. These materials are melted, designed and cooled in order to be released for use. Injection moulding is commonly and widely used to manufacture a variety of parts, usually for the car industry.

Initially, the moulding machines used the pressure technology to give the needed end products. This graduated to pneumatic cylinders and then the hydraulic systems which also borrowed from the die cast technology. The modern machines use the injection barrel of a plunging helical screw because it is fast and efficient.

The injection process comprises four easy steps which are:

1.Clamping — At this stage, the mould is held securely by the hydraulically powered clamping unit which in turn pushes the mould and exerts force to keep it securely closed while being injected.

2.Injection — The polymeric material which is available in powder form is transferred into the injection moulding machine by the injection unit for melting. Once it is molten, it is quickly injected into pressure packs under a certain temperature.

3.Cooling — The molten material solidifies quickly after a pre-determined cooling time. As the plastic cools, it adopts the shape of the desired part. The cooling process is sometimes affected by shrinkage and this is corrected at the injection stage where additional material is allowed to flow into the mould.

4.Ejection — This uses a particular mechanism to push the part out of the mould. Some force must be exerted since the part adheres to mould. A release agent may be sprayed on the surfaces of the mould to facilitate ejection.

The moulding design and tooling puts into consideration the part design. This includes the draft, wall thickness, radii and corners, ribs and bosses and the weld part lines. The draft describes the degree of a taper needed to allow the ejection of the moulded plastic. The ribs are necessary to add the structure strength of the part design. The bosses locate, mount and assemble the moulded parts. The radii help to avoid sharp corners and also help to strengthen the part.

A good plastic moulding company can be absolutely indispensable for various purposes, so if there’s even a remote possibility that you may need services of this type anytime soon, it’s in your best interest to research your local market for plastic services and find out which companies can work best for you. Remember that the quality of a custom plastic molding job can vary significantly from one company to another, and it’s important to invest in something that will work out exactly like you require.


About JasonMould Industrial Company Limited

Jasonmould is a manufacturer of plastic molds- injection mold, die casting moulds, plastic blow molding, rotational molding, medical plastic injection molding, two shot plastic injection molding, insert molding, overmolding, metal injection molding, micro injection molding, powder injection molding, ceramic injection molding, liquid injection molding, husky injection molding, household mold, casting mold, die mold tool, custom molds, china moulds, rapid prototyping tooling, plastic prototyping tooling, punch press tooling, die and tooling for mobile/ cell phone parts, automotive parts, vacuum cleaners, rechargeable tools, telephones, copiers, computers, multimedia speakers, and many other electronic products and household appliances. And also a plastic product manufacturer- plastic parts, plastic water tank, plastic balls, plastic containers, plastic buckle, plastic anchor, plastic hanger, plastic spoon, plastic pipe fitting, plastic tumble, plastic tableware, plastic cups, plastic bottles, plastic tray, plastic cosmetic container, plastic case, plastic food container, plastic chairs, plastic caps, plastic cap closure, plastic tubes, plastic water pipes, plastic knobs, plastic tubing, plastic utility boxes, plastic racks and so on.

Contact person: James Yuan
Company name: JasonMould Industrial Company Limited
Address: LongGang Village,LongXi Town,BoLuo County,HuiZhou City,GuangDong Province, China
Telephone: 86-752-6682869
Email: [email protected]

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