A 22 kW screw compressor running at 8.15 kW per m³/min burns an extra 39.6 kWh every day compared with a 6.5 kW/m³/min machine — roughly 19,558 CNY a year at 0.8 CNY per kWh. A screw air compressor factory acceptance test (FAT) is where you catch that gap before the machine ships. The same test is the fastest way to catch a weak airend, a noisy fan, or a leak before the crate is sealed. Run these 7 checks and release the final payment only when they pass.

Why a Screw Air Compressor Factory Acceptance Test Matters

Once you wire the balance, you lose your leverage. A machine that fails later — overheating, oil leaks, weak airflow — becomes a warranty argument fought across an ocean. The factory acceptance test moves that risk back onto the factory floor, where a fix costs hours of labor instead of a return freight bill. It costs you nothing but a checklist, a video call, and a refusal to pay until the numbers are proven.

The 7 Checks to Run Before You Pay

1. Run the unit at full load for 12 hours without a stop or alarm.
2. Record specific power in kW per m³/min at rated pressure.
3. Measure noise at 1 meter with panels closed — require 70 ± 2 dB.
4. Inspect hard piping and oil lines for leaks after the run.
5. Confirm the 52°C ambient design rating and a stable discharge temperature.
6. Cycle the compressor through load and unload at least ten times to check the controller and VFD.
7. Request a signed report with the serial number, date, and every reading.

Verify Specific Power With Your Own Numbers

Specific power is total input kW divided by air delivery in m³/min — lower is better. The benchmark table shows single-stage machines at 7.0–8.0 kW/m³/min and two-stage units at 5.9–6.8 kW/m³/min. The worked example is more useful: a 22 kW unit delivering 2.7 m³/min measures 8.15 kW/m³/min. Swapping it for a 6.5 kW/m³/min machine cuts power to 17.55 kW — 1.65 kW saved every hour, 39.6 kWh every day, and 19,558 CNY a year at 300 operating days and 0.8 CNY per kWh.

What the 12-Hour Run-In Must Prove

A non-stop, full-load run is the minimum proof a machine survives real duty. During it, the unit should hold pressure, the controller should log no alarms, and oil temperature should stabilize. With panels closed and the meter 1 meter from the unit, noise should hold at 70 ± 2 dB. A rising oil temperature across the run usually points to an undersized cooler, not a minor tune-up. If the factory cannot run the full 12 hours, or the unit trips and restarts without explanation, treat that as a failed test.

What Buyers Get Wrong

Three mistakes send buyers home with a bad machine:

• Trusting the brochure. A data sheet number is a claim, not a test result — ask for the serialized report.
• Paying for kilowatts instead of air. Specific power, not motor kW, decides your bill: a 22 kW unit at 8.15 costs more per cubic meter than a 22 kW unit at 6.5.
• Assuming testing costs extra. A serious factory runs the 12-hour test before shipping anyway; the signed report should be free.

Get the Signed Report Before the Balance Leaves

Hold the final payment until the factory sends the signed test report — 12-hour run, specific power reading, noise level, leak check, and the 52°C design point. Compare the specific power against a two-stage machine before you accept the number. If the factory cannot produce the report, the answer is simple: do not pay. For a machine matched to your real demand, or a live walk-through before you order, contact the Panrui team.