III. Features Description

• Swing Disc Backflow Prevention: The disc swings open under forward flow (driven by media pressure) and closes automatically via gravity within 1~2 seconds when flow reverses. This prevents pump cavitation, media mixing, and pipeline overpressure—critical for protecting water pumps and marine equipment.
• Material-Specific Corrosion Resistance: Brass bodies resist rust in freshwater systems, while aluminum bronze (containing 9~12% aluminum) withstands saltwater corrosion in marine environments, avoiding the rust-related jamming common in carbon steel valves.
• Tight Sealing Performance: EPDM/PTFE seats form a reliable seal with the disc, achieving API 598 leakage standards (no visible leakage under test pressure). EPDM handles hot water up to 120℃, while PTFE resists mild acids and solvents.
• Low Flow Resistance: The streamlined internal flow path and full-port design minimize pressure drop, allowing unobstructed media flow to reduce pump energy consumption in water circulation systems.
• Easy Installation & Maintenance: Flanged ends align with standard pipeline flanges for quick installation. The replaceable seat and accessible disc make maintenance simple—components can be replaced without removing the valve from the pipeline.

IV. Manufacturing Processes

• Material Inspection: Brass and aluminum bronze castings undergo ultrasonic testing to eliminate internal defects. Chemical analysis verifies alloy content (e.g., brass with 60~65% copper) to ensure corrosion resistance.
• Precision Machining: CNC lathes machine the valve body and disc to tight tolerances (±0.05mm), ensuring the disc swings smoothly without jamming. Flange faces are finished to Ra ≤1.6μm for leak-tight gasket sealing.
• Seat Assembly: EPDM/PTFE seats are molded to fit the valve’s sealing surface and bonded with high-temperature adhesive. The seat-disk contact area is lapped to enhance sealing precision.
• Testing:
  • Hydrostatic Test: Body tested at 2.4MPa (1.5×PN16) for 30 minutes; seat tested at 1.76MPa (1.1×PN16) with water to confirm no leakage.
  • Operation Test: 100+ open/close cycles verify smooth disc movement, with focus on closing speed under simulated backflow.