WCB Pneumatic Actuator Air Operated Flat Plate Parallel Slide Slab Gate Valve

III. Core Features: Dual Optimization of Structure and Drive

1. Flat Parallel Sliding Gate Design
   The gate adopts a parallel double-gate structure, achieving bi-directional sealing through close fit between two side sealing surfaces and seats, with uniform sealing specific pressure—suitable for media containing small particles or impurities. The full-bore flow path design reduces the flow resistance coefficient by 30% compared to wedge gate valves, with pressure drop of only 0.15bar in DN300 pipelines, minimizing pumping energy consumption.
2. High-Efficiency Pneumatic Actuator Drive
   Equipped with a fork-type pneumatic actuator for stable torque output, no-load opening/closing time ≤5s (DN200), supporting 4~20mA signal feedback and PLC linkage. Explosion-proof actuators (Ex d IIB T4) are optional for flammable environments, with protection class reaching IP66.
3. Multi-Scenario Sealing Solutions

• Main Seal: Metal+soft seal combination (e.g., stainless steel+PTFE) between gate and seat, complying with API 598 bubble-tight standard (leakage rate ≤0.1×DN mm³/s);
• Auxiliary Seal: Stem uses double seals of V-type packing+O-ring with blowout-proof design, ensuring no external leakage under high pressure.

4. Operation and Maintenance Convenience
   The pneumatic actuator is equipped with a manual override device for manual operation during air supply failure; the valve cavity has a drain port for regular impurity cleaning, extending seal life. Valves below DN500 allow in-line maintenance for seal replacement without pipeline disassembly.

IV. Manufacturing Processes: Precision Control from Material to Finished Product

1. Cast Steel Body Molding Process

• WCB material uses resin sand precision casting with pouring temperature controlled at 1550℃~1600℃; blanks are annealed at 900℃ to eliminate stress, with ultrasonic testing (UT) showing internal defect rate ≤0.5%;
• Body and gate blanks undergo aging treatment to reduce machining deformation, with dimensional tolerance controlled within ±0.3mm (<DN100).

2. Actuator Assembly and Testing

• Pneumatic actuator cylinders are die-cast from aluminum alloy, with inner surfaces hard anodized to reduce friction coefficient by 40%;
• After assembly, each valve undergoes 1.5x design pressure shell strength testing (30-min hold) and 1.1x pressure sealing testing (15-min hold), with soap water for external leakage detection.

3. Surface Treatment and Coating

• Carbon steel bodies are sandblasted (Sa2.5 grade) and sprayed with epoxy zinc-rich primer (dry film thickness ≥80μm), topcoated with polyurethane anti-corrosion coating (total thickness ≥200μm);
• Stainless steel components undergo electropolishing with surface roughness Ra≤0.8μm, suitable for food-grade or corrosive media scenarios.