The bottom half of the Module Seal consists of a 1/2” thick rubber membrane at the top of the mounting post. This provides a hermetic seal for the Isolator Ring keeping the instrument oil in and the air out. The top half of the Module Seal is the "Stinger Fitting" a brass or stainless steel fitting with a needle projecting out of the bottom. Replacing the gauge without compromising the integrity of the vacuum fill – and without removing the Isolator ring from the process pipe - is simple:
- Close the Block Valve.
- Unscrew the Lock Ring.
- Pull the gauge and stinger fitting out as a complete unit.
- Plug the new gauge and stinger assembly into the Module Seal.
- Re-tighten the Lock Ring.
- Open the Block Valve.