Rubber products come in many shapes, such as square, round, special shapes, etc. Different shapes are produced using different processes. Let’s take a look at the differences between molding and extrusion.

Molding is a rubber processing method in which rubber raw materials are heated and pressurized in a closed mold cavity to be formed into products. Molding generally involves placing a powdery piece of rubber in the cavity of a heated mold, and then closing the mold and pressurizing it. It is formed and solidified or vulcanized, and then demoulded into products. This method is particularly suitable for the molding and processing of thermosetting products.

advantage:

1.Can be made into any shape

2. Various shapes such as O-rings, sealing rings, oil seals, rubber stopper, rubber mount, rubber gasket etc.

3. High precision, regular and beautiful shape

shortcoming:

1. Generally, only special-shaped rubber parts with a diameter and length less than 650 mm can be made

2. The production process will produce a lot of burrs and waste products, which will take time to repair.

3. The mold cost is relatively expensive and the early mold development cycle is long.

Extruded sealing strips are usually formed by extruding materials through an extrusion machine. When the temperature of the extruder changes from low to high, the extruded cross-sectional expansion rate changes from small to large; the mixing of different types of rubber or different rubber contents Glue, the expansion rates of the cross-sections of the extruded products are different; generally the extruded sealing strips are long, and the length can be cut at will.

advantage:

1. Short production cycle and high capacity

2. Little waste is produced

3. Molds are cheap and development is convenient and fast

shortcoming:

1. Can only be made into strips

2. The accuracy is slightly worse than that of molded products, and some shapes are difficult to produce.

As mentioned above, rubber molding and rubber extrusion processes each have their own pros and cons. Different products require different processes.