I. Vulcanization Molding Process Principles

1. Raw Material Formulation and Pretreatment
   • Using Ethylene-Propylene-Diene Monomer (EPDM) rubber as the base material, adding vulcanizing agents (such as peroxides), accelerators, reinforcing agents (carbon black), softeners, and other additives. These are mixed in specific proportions and processed into uniform rubber compounds via internal mixers and open mills.
   • According to the joint specifications (e.g., DN50-DN2000), the rubber compounds are cut into corresponding-shaped blanks, with nylon curtain cloth or steel wire mesh reinforcement layers embedded inside to enhance pressure resistance and tear strength.
2. High-Temperature Vulcanization Molding
   • The rubber blanks and metal flanges (or threaded joints) are placed into custom molds, then vulcanized at 150-180°C and 10-15MPa pressure for 20-60 minutes using a plate vulcanizer.
   • During vulcanization, rubber molecular chains form a three-dimensional network structure through cross-linking reactions, while chemically bonding with metal components to ensure the joint's overall strength and sealing performance.

II. Core Performance Advantages

III. Typical Application Scenarios

1. HVAC Systems
   • Connection of central air conditioning chilled water (7°C-65°C) and cooling water (32°C-37°C) pipelines, absorbing pump vibrations to prevent transmission to building structures.
   • Displacement compensation for steam heating pipelines (≤150°C), preventing rubber aging and leakage caused by high-temperature steam.
2. Municipal and Water Supply/Drainage Engineering
   • Urban tap water pipelines (buried or outdoor): Resists soil corrosion and foundation settlement, compensating for pipeline displacement.
   • Aeration pipelines in wastewater treatment plants: Resists sewage corrosion, adapts to aeration equipment vibrations, and prevents interface air leakage.
3. Chemical and Environmental Protection Equipment
   • Pipelines transporting dilute acids (e.g., 5% sulfuric acid) and alkaline solutions (e.g., 10% sodium hydroxide), replacing metal compensators to reduce costs.
   • Spray pipelines in desulfurization and denitrification systems: Resists wet flue gas corrosion and absorbs water hammer impacts during spray equipment start/stop.
4. Marine and Offshore Engineering
   • Marine engine room cooling water pipelines (seawater or fresh water): Resists salt spray corrosion and hull sway displacement, ensuring stable pipeline system operation during navigation.

IV. Selection and Usage Notes

• Material Confirmation: Ensure EPDM content ≥60% to avoid inferior recycled rubber affecting temperature and corrosion resistance.
• Pressure Matching: Working pressure must be ≤ rated value (e.g., 1.6MPa); for vacuum systems, select models with steel wire reinforcement.
• Installation Taboos: Forbid forced twisting of the joint during flange connection; add thermal insulation layers in high-temperature scenarios and avoid direct sunlight to prevent accelerated rubber aging.