Hard sealed Manual Cast Steel Gate Valve WCB High Temperature/high Pressure Control

III. Core Features: Hard-Seal Technology and Operational Adaptability

1. Advantages of Hard-Seal Structure
   The seat and gate are hardfaced with carbide alloys (e.g., Stellite), with surface hardness ≥HRC58. The wear resistance is over 3 times that of ordinary steel, capable of withstanding high-velocity fluid erosion and particle medium wear—especially suitable for interception scenarios involving solid particles or high-viscosity media. The sealing surface uses a grinding process with flatness error ≤0.01mm, achieving zero-leakage sealing (bubble-tight standard).
2. Wide Temperature and Pressure Adaptability

• Temperature Resistance: WCB material ensures stable operation within -29℃~425℃, while stainless steel adapts to low-temperature environments with corrosive media;
• Pressure Resistance: Class 2500 products can withstand 42MPa high pressure. The valve body adopts a thickened design, with pressure-bearing capacity 20% higher than conventional valves, meeting strict conditions like high-pressure steam pipelines and wellhead devices.

3. Multi-Standard Compatibility and Installation Flexibility
   Products comply with international standards such as API, JIS, and ANSI, with flange dimensions and face-to-face lengths compatible with mainstream international projects. Connection types cover flanged and welded options, supporting sealing forms like RF raised face and RTJ ring joint to adapt to installation needs of different pipeline systems.

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

1. Raw Material Selection and Pretreatment
   WCB cast steel uses an electric furnace melting + out-of-furnace refining process, with sulfur and phosphorus content controlled below 0.03% to ensure material impact resistance. Stainless steel materials undergo vacuum degassing to reduce inclusions and enhance corrosion resistance. All materials must pass spectral analysis, tensile testing, and impact testing to ensure composition and mechanical properties meet standards.
2. Precision Casting and Machining

• Casting Process: Resin sand precision casting is adopted, with the valve body surface finish Ra≤12.5μm and dimensional tolerance controlled within ±0.5mm to avoid casting defects;
• Machining: CNC vertical lathes and machining centers are used for precision machining of sealing surfaces, combined with special grinding equipment to achieve sealing surface roughness Ra≤0.8μm, ensuring the fitting accuracy of the sealing pair.

3. Full-Process Quality Control

• Pressure Testing: Each valve must pass a shell strength test at 1.5x design pressure and a sealing test at 1.1x design pressure, with pressure maintained for ≥15 minutes without visible leakage;
• Nondestructive Testing: Key welds undergo RT radiography (Grade II qualification), and casting surfaces use MT magnetic particle testing to eliminate defects such as cracks and pores;
• Life Testing: Sampling for 5,000 on-off cycle tests to ensure no degradation in sealing performance, guaranteeing long-term reliability.