The
Pressure seal bonnet (PSB) check valves provided by Weldon are adopted for high pressure service. Compared to Bolted Bonnet (BB) check valve, which the body flange and bonnet flange are joined by studs and nuts, when the system pressure increases, the potential for leakage through the body / Bonnet joint also increases, the unique structure of the
pressure seal Bonnet is that the body-Bonnet joints seals improves as the internal pressure in the
PSB check valve increases, the higher the internal pressure, the greater the sealing force.