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Level Measurement · Glossary

What is a Dry Leg?

gas filled LP impulse lineLevel Measurement

A dry leg is a low side impulse line that stays full of gas, used for DP level when the vapour does not condense.

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Dry Leg Explained

With a dry leg, the LP side sees only the gas pressure above the liquid, so the range starts at zero DP for an empty tank.

If vapour condenses, liquid slowly fills the leg and the level reads low. Fit a drain pot, slope the line, or change to a wet leg or seals.

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Calculators for Dry Leg

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Frequently Asked Questions

What is a Dry Leg?

A dry leg is a low side impulse line that stays full of gas, used for DP level when the vapour does not condense.

How do I know if a dry leg has filled?

Level reads low and drifts; draining the LP side brings it back.

Can a dry leg be heat traced?

Yes, tracing keeps it above the dew point so vapour does not condense.

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Related Terms

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More Level Measurement Terms

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All level measurement terms · Full glossary A to Z

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