General Valve TWIN SEAL

July 21, 2011

The original Twin Seal led to the rigid requirements of double block and bleed service and resulted in the

market leading Twin Seal valve. The patented Twin Seal valve is a non-lubricated, resilient seal,

expanding plug-type valve which has a mechanical means of freeing the plug before it is rotated from

the closed to open position. The plug and seal slips rotate freely, with no seal to body contact,

eliminating seal abrasion and wear. The unique, dove-tailed design plug is operated inward between

the slips, mechanically wedging out the seal slips for a positive upstream and downstream

shut-off. This creates a positive, mechanical shut-off of each valve port independent of springs,

system pressure or flow. In addition, the primary seals are reinforced by a secondary metal-tometal

seal, resulting in a superior, fire-safe design. Seals may be repaired with common tools

while the valve is in-line, after the line has been depressurized and drained.