Application:

1. Piping upstream of shut-off or regulating valves in the outlet piping of the heater.

2. Gas-phase piping at the top of a distillation tower that is overpressurized due to interruption of cooling water or reflux or excessive heat input to the reboiler

3. Outlet piping for vessels of low boiling point liquids (liquefied gases, etc.)

4. Outlet piping for positive displacement pumps and compressors where the outlet may be shut off.

5. Safety valves on pump inlet piping due to leakage from pump outlet check valves in some cases.

6. Piping systems where valves are closed at both ends and thermal expansion or vaporization of liquids occurs

7. Frequent overpressurization and large temperature fluctuations.

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