H-Seal
- Where gas/pneumatic valves are required to be sealed tightly, problems occur where
a positive seal results in a passing valve
- Using the H-Tap Tool, sealant with a high viscosity can be introduced into a valve
so that as the valve is operated the sealing faces are coated, creating the required
seal.
- The viscosity of the sealant means that the sealant does not travel down the system
causing problems in other components.
- The quality of the sealant means that it will not harden over time.
- This system of sealing passing valves is patented and the National Grid – Gas, approved,
best practice to deal with passing valves (Low and Medium Pressure, Procedure No.
T/PR/V/16).
- This system is also used as a preventative maintenance facility, used where guaranteeing
a valve will not pass, is deemed vital to the operation of the network.