the diagram below shows how raw materials are used to make plastic products

The diagram demonstrates the process of making plastic products from the oil refinery. There are three main stages including turning raw materials into plastics, moulding and packing.

In the first stage, the raw materials for plastic goods come from the oil refinery and stored in big tanks. The disordered molecules pass through the high-pressure oven and become long molecules of plastic. At the following stage, plastic granules transfer by a long tube to the injection moulder where plastics are melted and forced into a mould.

In the last step, people are involved. Quality controllers check the end products releasing after the moulding processing and throw waste products away. Then, workers store the qualified products in the warehouse after packing them up into boxes.