600 Ton Automotive Rubber Injection Molding Machine

High Temp Precision 600 Ton 4 RT Automotive Rubber Injection Molding Machine

In the preparation of raw materials, the ingredients must be weighed according to the formula. In order to allow the raw rubber and the compounding agent to be uniformly mixed with each other, some materials need to be processed:

1. Basic process

• Along with the rapid development of modern industry, especially the chemical industry, there are many kinds of rubber products, but the production process is basically the same. The product is made of general solid rubber (raw rubber), and its production process mainly includes:
• Raw material preparation → Mastication → Mixing → Forming → Vulcanization → Resting → Inspection

2. Raw material preparation

• The main materials of rubber products are raw rubber, compounding agent, fiber material and metal material. Raw rubber is the basic material; compounding agent is auxiliary material added to improve certain properties of rubber products; fiber material (cotton, hemp, wool and various rayon, synthetic fiber) and metal material (steel wire, copper wire) It is used as a skeleton material for rubber products to enhance mechanical strength and limit product modification.
• In the preparation of raw materials, the ingredients must be weighed according to the formula. In order to allow the raw rubber and the compounding agent to be uniformly mixed with each other, some materials need to be processed:
• The raw rubber should be softened in a 60--70 ° C drying room, then cut into pieces and broken into small pieces;
• Bulk compounding agents such as paraffin, stearic acid, rosin, etc. are to be crushed;
• If the powdery compounding agent contains mechanical impurities or coarse particles, it needs to be removed by screening;
• Liquid compounding agents (pine tar, coumarone) need to heat, melt, evaporate water, and filter impurities;
• The compounding agent should be dried, otherwise it will be easy to agglomerate and mix and disperse when it is not uniformly dispersed, and bubbles will be generated during vulcanization, thereby affecting product quality;

3. Mastication

• Raw rubber is elastic and lacks the necessary properties (plasticity) during processing, so it is not easy to process. In order to improve its plasticity, the raw rubber is plasticized; thus, the compounding agent is easily dispersed uniformly in the raw rubber during the kneading; at the same time, it also contributes to the improvement of the permeability of the rubber during the calendering and molding process (infiltration) Inside the fiber fabric) and molding fluidity. The process of degrading the long-chain molecules of raw rubber to form plasticity is called mastication. There are two kinds of raw plastic mastication methods: mechanical mastication and thermoplastic refining. Mechanical mastication is the process of shortening the degradation of long-chain rubber molecules and changing from a highly elastic state to a plastic state by the mechanical extrusion and friction of the plasticizer at a relatively low temperature. Thermoplasticing is the introduction of hot compressed air into the raw rubber. Under the action of heat and oxygen, the degradation of long-chain molecules is shortened, thereby obtaining plasticity.