Conval Clampseal® Fire-Safe Valves are ideal for refining and chemical plants where fire safety is a major concern.
- Industry’s Lowest Life Cycle Costs
- Exceeds API Standard 6FA
- Retrofit with any Clampseal® Globe Valve
- Single-piece Gland
- Cartridge-type Packing Chamber
- Pressure Assisted Backseat
Standard SizesSizes through 4"
Pressure RatingASME Class through 2500 #
Standard MaterialsA105, F22, F91, F92, F316, F347, InconelTM, MonelTM and other materials.
ConnectionsSW and BW Ends
Special ends available
AccessoriesActuators - electric, pneumatic, or hydraulic
Limitswitch - Single or double
Locking Devices - open, closed, or both
Special TestingTested and passed API Standard 6FA
Meets API Standard 6FA by extremely high marginsIn a typical globe valve, if the yoke is exposed to the direct flame of a fire, it will expand at a rate much greater than the stem. Thermal effects cause the yoke arms to grow, which makes the disc lift up off the seat, leading to considerable leakage. This is true of virtually all globe valves now on the market.
Conval has developed a simple mechanism that compensates for thermal expansion. The stem bushing is allowed to float in a recess in the top of the yoke and is loaded by a series of Belleville washers. The Bellevilles maintain a load, forcing the stem assembly down into the seat, even when the yoke expands at the high temperatures of a refinery or chemical fire.
The Conval fire-safe Clampseal® valve has been tested and successfully passed the rigorous test procedure defined by the American Petroleum Institute (API) Standard 6FA. In brief, this procedure calls for the test valve to be placed in line and pressurized to 75% of rated pressure, then subjected to a 1400-1800°F fire for 30 minutes. The valve is then quenched with water to cool it to ambient temperature, cycled to prove operability, and then subjected to further pressure testing. The valve is required to maintain strict leakage allowances during and after the burn.