What is the basic classification of forming moulds?

Wed Apr 26 14:39:45 CST 2023

Forming moulds, also known as moulds, are moulds made to scale according to the shape and structure of a physical object and are used to make the material into a certain shape by pressing or pouring.

Not the same plastic molding method, requiring the use of different principles and structural characteristics of the molding mold.

Injection moulding: The plastic is first heated and melted in the heated barrel of the injection moulding machine, then pushed by the screw or piston of the injection moulding machine, through the nozzle and the pouring system of the mould into the mould cavity, and finally hardened and shaped in the cavity, which is the simple process of injection moulding, and the mould used for injection moulding is called injection moulding. Injection moulds are mainly used for the moulding of thermoplastic products, but in recent years they are increasingly being used for the moulding of thermosetting plastics. Injection moulding accounts for a large proportion of plastic products, so about half of the production of plastic moulds are injection moulds.Forming moulds

Extrusion moulds: also known as headers. Let the plastic in the viscous flow state at high temperature and pressure through the mouth mold with a specific cross-sectional shape, and then cooled at a lower temperature to set, used to produce a continuous profile with the required cross-sectional shape of the molding method called extrusion molding, and for plastic extrusion molding mold is called extrusion molding mold.

Hollow products blow moulding mould: extrusion or injection moulding out of the still in the plasticized state of the tubular blank, while hot into the mould forming cavity, immediately in the centre of the blank into the compressed air, so that the blank expansion and cling to the mould cavity wall, cooling hardened into a hollow product. The mould used for this method is the hollow product blow mould.

Vacuum or compressed air moulding mould: This is a separate negative or positive mould. The pre-made plastic sheet is pressed tightly around the perimeter of the mould, heated to soften it, then vacuumed on the side immediately adjacent to the mould or filled with compressed air on the opposite side to keep the sheet close to the mould; the product is cooled and shaped. This method of moulding is less stressful and less demanding, and can even be made from non-metallic materials.

Compression moulding moulds: referred to as compression moulds. The plastic material is added directly to the open cavity of the mould and then the mould is closed. The plastic becomes fluid and fills the cavity under heat and pressure; the plastic then hardens and sets due to chemical or physical changes, this method is called compression moulding and the mould used is called a compression mould. Most of these moulds are used for thermosetting plastics, but also for thermoplastics. There are also cold press moulds for forming PTFE blanks without heating.

Die-casting moulds: also known as transfer moulds. The plastic raw material is added to the preheated filling chamber and then pressure is applied to the press column. The plastic melts at high temperature and pressure and enters the cavity through the pouring system of the mould and gradually hardens into shape, this method of moulding is called die-casting moulding and the mould used is called die-casting moulding mould. This mould is mostly used for the moulding of thermosetting plastics.

In addition, there are foam moulds, glass fibre reinforced plastic low pressure moulds and so on.