The B1 Series Union Bonnet Tandem Valves have been developed by AS-Schneider to be used as primary isolation valves for instrumentation lines where highest requirements are placed on the safety of the shut-off function.
The safety of the maintenance personnel is paramount when performing service work on pipe assemblies. Especially with media under high pressure and temperature or with hazardous media two valves positioned in series are often used. This tandem arrangement shall provide a positive isolation from the process.
The B1 Series was especially developed by AS-Schneider for these high demands and comprises two separate independent Union Bonnet Valves in a single body. This engineering design represents a very compact solution and is available in many materials (1.5415, 1.7380, A182 F91, 316/316L …). The high-quality valve head units are flange-mounted to the valve body with a union nut (union bonnet design); the bore size on the valve seat is 11mm.
The sealing to atmosphere is performed by the non-rotating valve stem. This design achieves a low actuating moment, reduces the load on the sealing and thus increases the service life. Another advantage is the avoidance of seizing between valve tip and valve seat. The B1 Series is equipped with a metal back seat, which relieves the stem sealing when the valve is completely open and guarantees positive sealing even when the packing fails.
The B1 Series Union Bonnet Tandem Valves are available for pressures up to 600 bar and temperatures up to 550° C.