Air Leakage

Compressed Air Leakage: Causes & How to Calculate Air Loss

Compressed air leakage is air lost from the system without producing useful work. In many factories, leakage can reach up to 25% of total compressed air capacity, increasing energy consumption and operating costs.

Practical Guide

Common Causes of Compressed Air Leaks

  • Leaking valves
  • Leaks at threaded fittings and flange joints
  • Leaks at welded joints or defective weld points
  • Damaged piping or poor pipe connections
  • Faulty solenoid valves
  • Blocked or malfunctioning condensate drains
  • Incorrect installation of dryers and filters
  • Corroded or aged compressed air pipelines

Simple Method to Estimate Current Air Leakage

  1. Turn off all air-consuming equipment and stop the compressor.
  2. Record the receiver pressure and the time.
  3. Calculate the leakage flow using the formula below.
Tip: The longer the measurement time, the more accurate the result. Repeat the test several times and use the average value.

Leakage Flow Formula

Q = V × (P₁ − P₂) T × 1.013 (m³/min)
  • Q: leakage air flow converted to standard conditions (m³/min)
  • V: receiver volume; include piping volume if significant (m³)
  • P₁, P₂: gauge pressures at two measurement times (bar g)
  • T: time for pressure to drop from P₁ to P₂ (minutes)
  • 1.013: approximate atmospheric pressure (bar) for absolute pressure conversion

Use the Calculator Below

Enter P1, P2, V, and T to estimate your current leakage flow, plus the yearly energy loss and cost.

Formula to Calculate Air Leakage Flow from an Air Receiver Tank

Based on the tank volume and the pressure drop from P1 to P2 over a time period T (minutes). The result is the estimated leakage flow converted to standard conditions in m³/min.

Q = V × (P₁ − P₂)/(T*1.013) (m³/min)
  • Q: leakage air flow converted to standard conditions (m³/min).
  • P₁, P₂: gauge pressure at two measurement points (bar g).
  • V: receiver tank volume (add connected piping volume if it is significant) (m³).
  • T: time for pressure to drop from P₁ to P₂ (minutes).
  • 1.013: approximate atmospheric pressure 1.013 bar, used to convert to absolute pressure.

You may include the connected piping volume if it is large enough to be significant.