When a customer requires 40" Class 600 metal-seated trunnion ball valve that meets both zero leakage and DIB-1 (double-piston effect), the demands on structural design, manufacturing precision, and sealing technology are significantly higher.
The challenge lies in the combination of structural deflection caused by high pressure under large-bore, hard-seated conditions, and the precision control required for oversized components-both of which make long-term, stable zero-leakage performance substantially more difficult.
Our approach:
Support plate structure-line thrust is transferred directly to the body through the support plates, bypassing the stem, minimizing structural deflection under high pressure.
Micron-level machining precision-critical mating surfaces are held to micron tolerances, ensuring assembly consistency and sealing stability.
Special piston rings are installed behind the seats, together with micron-level fit control, they ensure reliable DPE seat activation under differential pressure from either direction.
Sealing surfaces are treated with HVOF-applied hard alloy coating+mirror-grade precision lapping, improving erosion resistance, wear resistance, and seal life.
Zero leakage is not the result of a single technology-it is the synergy of structural design, precision manufacturing, and sealing technology.