Molding is a process of giving shapes to articles. The mold manufacturing business has grown due to the increasing demand of molded shapes. Everyone wants an attractive shape article in their showcase. And with the help of molding, the manufacturing of these shapes has become easy. Also the technology has played a role in this. With increasing technology, manufactures can now produce complex shape molds with great detail. They are not only used for decoration but also help to design machines. There are some parts of the machine which need to be perfectly shaped otherwise the machine will not work properly. So the machine manufactures also use molds for designing machine parts with perfect shape. Therefore mold manufacturing industry also plays a key role for the manufacturing of machine parts. Molding can be done with different materials ranging from plastic to iron and steel. The material choice depends on the work a mold as to perform. The demand of molded articles has now grown in machine industry. The molded parts are used in medical services, silicon wafers, aerospace industry and every manufacturing industry.
Plastic is the primary material used for the molding process. It is a syntactic material with varying properties. The two major and important categories of plastic are thermosetting and thermoplastic. Thermosetting plastic are those that one cooled, do not change their shape. That is once they acquire the shape, then they are permanent. You cannot change the shape. They are hand and durable. On the other thermoplastic are those which can change shape when heated. They become soft on heating. Now, after classifying plastic let’s take a look on types of mold manufacturing of plastics.
Types of molding process of plastic
- Molding of plastic using casting: – casting is the simplest method for plastic molding. There is no requirement of complex methods and technologies. Molten plastic is transferred in a mold. And then it is cooled and mold is removed. With this process you can make solid plastic articles of the desired shape. This process is commonly used for making sheets of plastic.
- Injection modeling: – first the plastic is melted in hooper. Then it is injected in a closed, chilled mold. Plastic takes the shape of mold. Once the plastic is set, mold is opened and the plastic object is taken out.
- Blow molding: – a tube is fitted into a mold which is of particular shape when inflated. The molten plastic is pour into the mold and air is blown. Plastic formed around tube. After cooling it is taken out.
- Compression modeling: – it requires an intensive labor work. Therefore it is used for large scale production. Plastic in its molten state is poured into a mold. Then a send mold is used to press and squeeze the plastic.
- Rotational molding: – hollow shapes are made using this method. The mold is placed between tow mechanical arms which rotates it. While the plastic is inside, it takes the shape of outside mold and creates a hollow object.