1. Basic process flow
There are many types of rubber products, but the production processes are basically the same.
The basic process of rubber products using general solid rubber (raw rubber) as raw material includes six basic processes: mastication, mixing, calendering, extrusion, molding, and vulcanization.

Of course, basic processes such as raw material preparation, finished product sorting, inspection and packaging are also indispensable.
The rubber processing process is mainly a process of resolving the
conflict between plasticity and elastic properties.
Through various technological means, the elastic rubber is turned into plastic plasticized rubber, and then various compounding agents are added to make semi-finished products. Then, through vulcanization, the plastic semi-finished products are turned into rubber products with high elasticity and good physical and mechanical properties. 


2. Raw material preparation
1. The main raw material of rubber products is raw rubber, which is collected from rubber trees growing in the tropics and subtropics by manually cutting the bark.
2. Various compounding agents are auxiliary materials added to improve certain properties of rubber products.
3. Fiber materials (cotton, linen, wool and various man-made fibers, synthetic fibers and metal materials, steel wire) are used as the skeleton material of rubber products to enhance mechanical strength and limit product deformation.
During the preparation of raw materials, ingredients must be accurately weighed according to the formula. In order to make the raw rubber and compounding agents evenly mixed with each other, the materials need to be processed.
The raw rubber should be softened in a drying room at 60--70°C before being cut and broken into small pieces. Mixing agents that are lumpy, such as paraffin, stearic acid, rosin, etc., should be crushed.
If the powder contains mechanical impurities or coarse particles, it needs to be screened to remove liquids such as pine tar and coumaron. It needs to be heated, melted, evaporated, and filtered. The compounding agent must be dried otherwise it will easily agglomerate and cannot be dispersed during mixing. Bubbles generated during uniform vulcanization will affect product quality

3. Refining
Raw rubber is elastic and lacks the plasticity necessary for processing, making it inconvenient to process.
In order to improve its plasticity, the raw rubber must be masticated so that the ingredients can be easily and evenly dispersed in the raw rubber during mixing. At the same time, it also helps to improve the permeability of the rubber into the fiber fabric during the calendering and molding processes. and molding fluidity.
The process of degrading the long-chain molecules of raw rubber to form plasticity is called mastication. There are two methods of mastication of raw rubber: mechanical mastication and thermal mastication.
Mechanical mastication is the process of degrading and shortening long-chain rubber molecules from a highly elastic state to a plastic state through the mechanical extrusion and friction of the mastication machine at a not too high temperature. Thermoplasticizing is the process of passing hot compressed air into raw rubber to degrade and shorten long-chain molecules under the action of heat and oxygen to obtain plasticity.

4. Mixing
In order to adapt to various usage conditions and obtain various properties, as well as to improve the performance of rubber products and reduce costs, different compounding agents must be added to raw rubber.
Mixing is a process in which the masticated raw rubber is mixed with the ingredients, placed in a rubber mixing machine, and mechanically mixed to completely and evenly disperse the ingredients in the raw rubber.
Mixing is an important process in the production of rubber products. If the mixing is uneven, it will not be fully developed.