A method of moulding in which the moulding material is first placed in an open, heated mould cavity. The mould is closed with a top force and pressure is applied by means of vertical press to force the material to flow throughout all mould areas.

The process employs generally thermosetting resins with high strength fiberglass reinforcement ( composite), either in the form of sheets (SMC) or masses (BMC) and heat and pressure are maintained until the material undergoes a chemical change which permanently hardens it into the shape of the mould.

The main advantage of this technique is its ability to mould large, fairly intricate geometrical parts, while the cycle time per part is rather short.

 

The process allows also to get directly a variety of thickness, holes, knobs, flanges and even metal insertions.Till today compression moulding of thermosetting composite is recommended for the production of enclosures, boards , panels and components for the electrical distribution system, as well as for the automotive industry ( bumpers).

 

It is the most widely used technique for manufacturing a variety of parts from thermoplastic materials. The material, in form of granules, first drops from a hopper into the heated chamber of a press where is electrically melted before being injected into the mould by means of a piston. Pressure and temperature are maintained until the molten resin solidifies, and the formed part is ready to be released.

 

The main advantages of this technique are.

 

• production of more complex geometrical parts
• high productivity
• low production cost
• high process automation
• production of parts from smallest components to entire body panels of cars
• use of large variety of thermoplastic materials
• co-injection of various materials and colours

 

This process allows the productionin a single cycle of parts made of various materials like thermoplastic and thermosetting resins, metals.

 

Typical applications are:

 

• co-moulding with metal insertions
• electronic connectors

 

Many plastic components need to have the surface finish applied before use. This can act as a decorative layer, or protective layer, or to alter the surface properties. If this effect is applied during the moulding process, it can reduce time, space, material and machinery requirements.

It also allows to supply complete systems, rather than just moulded components. In-mould decoration techniques include the in-mould application of film, in-mould priming, in-mould labelling and the injection of paints.

 

These techniques have widespread use in the plastic industry and the marketplace is expanding. The car and mobile-phone industries, packaging and toys are example of key areas of growth.

 

Pultrusion is a manufacturing process for producing continuous lengths of structural profiles. Raw materials include a liquid resin mixture and reinforcing fibers. The process involves pulling these raw materials through a heated steel forming die using a continuous pulling device.