The manufacturing process of rubber end gaskets mainly includes key steps such as raw material preparation, mixing, preforming, compression molding and vulcanization, post-processing, and quality inspection. This process ensures that the gaskets have good sealing performance, elasticity, and durability, making them suitable for connection and sealing parts in industrial equipment.
1. Raw Material Preparation Selecting a suitable rubber base material is fundamental. Common materials include:
- Ethylene Propylene Diene Monomer (EPDM): Strong weather resistance, suitable for outdoor or high-temperature environments.
- Nitrile Butadiene Rubber (NBR): Excellent oil resistance, widely used in hydraulic systems.
- Fluororubber (FPM): High temperature and corrosion resistance, suitable for harsh working conditions.
- Natural Rubber (NR): Good elasticity and excellent processing performance.
Additional additives such as fillers (e.g., carbon black, talc), vulcanizing agents (e.g., sulfur), accelerators, and antioxidants are added to improve physical properties and service life.
2. Ingredient Formulation and Mixing: Rubber raw materials and various additives are added to an internal mixer or open mill according to the formula ratio and thoroughly mixed to form a homogeneous compound. This process directly affects the performance stability of the final product.
3. Preforming: The compound is calendered or extruded into sheet or strip semi-finished products for subsequent placement in molds and shaping, improving dimensional accuracy.
4. Compression Curing: The preformed rubber compound is placed into a custom mold and subjected to high temperature (typically 140℃–170℃) and high pressure (10–20 MPa) on a flatbed vulcanizing machine. This causes the rubber to flow and fill the mold cavity, simultaneously completing the vulcanization reaction. During vulcanization, the molecular chains cross-link, giving the rubber high elasticity and mechanical strength.