Why leak audits matter

Compressed-air leaks consume compressor capacity without creating production value. They can also pull pressure down, lengthen loaded run time and encourage operators to raise setpoints. A leak audit is not a one-time walk-around; it is a controlled maintenance process that connects detection, repair and verification.

Establish a baseline

Record operating pressure, compressor loaded/unloaded state, flow where metering exists, run hours and production condition. If the plant has a non-production period, a no-production flow measurement is useful because most remaining demand is leakage or known essential use. For load/unload machines, a qualified technician can estimate demand from loaded time, but control behaviour and compressor data must be understood.

Plan the survey

Divide the network into zones: compressor room, main header, production bays, machines and end uses. Obtain a current piping drawing or mark one during the survey. Perform ultrasonic detection while the system is pressurised and, where practical, when surrounding production noise is lower. Use appropriate access equipment and never reach into moving machinery.

Detect and tag

Scan joints, couplings, hoses, quick connectors, FRLs, drain valves, solenoids, cylinders and abandoned branches. Confirm each indication from more than one angle to separate a leak from reflected sound. Attach a durable tag and record a unique ID, location, component, detector reading, pressure, photograph, accessibility and safety requirements.

Estimate and prioritise

Use the detector manufacturer’s validated method or direct flow measurement where feasible. Prioritise by estimated loss, production impact, safety, repair complexity and whether isolation requires downtime. Large continuously pressurised leaks normally rank above intermittent small leaks, but a small leak in a critical control line may deserve urgent attention.

Repair safely

Only competent personnel should repair equipment. Isolate the correct section, lock out energy, depressurise and verify zero pressure. Replace damaged components with pressure-rated compatible parts; do not rely on temporary sealants or tightening beyond manufacturer limits. For recurring joint failures, investigate vibration, alignment, hose strain, corrosion or incorrect support.

Verify results

Remove a tag only after the repaired point has been rechecked under pressure. Repeat the baseline measurement under a comparable production state. If flow or compressor loaded time does not improve as expected, look for missed leaks, control changes or essential demand. Document unrepaired items and ownership.

Build a sustainable programme

• Assign an owner and survey frequency by zone.
• Include leak inspection in routine operator rounds.
• Use a digital register with status and verified close-out.
• Track non-production flow or loaded-time ratio consistently.
• Inspect frequently disturbed hoses and quick couplings more often.
• Review pressure after repair; lower it only after confirming machine needs.

Combine leak work with the compressed-air service warning-sign checklist and broader system maintenance.