1. Visual Inspection

The cast, welded and machined surfaces on the outer surface of the air compressor shall be cleaned thoroughly. They shall be free of rust, scale and welding spatter; the painted surfaces shall be flat and smooth with uniform color. The air pipes, water pipes and oil pipes of the air compressor shall be arranged neatly.

2. Materials

The materials used for the main components of the air compressor shall comply with the design and specification requirements.

3. Pressure Resistance and Air Tightness

Components subjected to gas pressure shall undergo a hydrostatic test at 1.5 times the maximum working pressure; the hydrostatic test pressure for water circuits and water chambers is generally 0.5 MPa; for submersible air compressors, it is 0.75 MPa. All the above tests shall last for 30 minutes, and no leakage is allowed.

4. Air, Water and Oil Pressure

Measure the pressure in accordance with the method specified in A2.1 of GB/T 3853-1998.

5. Safety

Start the air compressor and adjust the outlet stop valve; the pressure of the air compressor shall rise steadily. Adjust the safety valves of the air compressor one by one (the safety valves of each intermediate stage may be adjusted at the final stage), so that the safety valves open at the set pressure value. The setting times shall not be less than 3 times, and the safety valves after setting shall be sealed with lead.

6. Volumetric Flow Rate

Measure the volumetric flow rate of the air compressor under suction conditions in accordance with the method specified in GB/T 15487. When the air compressor operates under rated working conditions, the measured volumetric flow rate, converted to the nominal volumetric flow rate, shall not be less than 95% of the specified value.

7. Shaft Power

Measure the power in accordance with the method specified in A2.6 of GB/T 3853—1998. When the air compressor operates under rated working conditions, the measured shaft power shall not exceed the specified value.

8. Vibration

When the air compressor operates under rated working conditions, measure the vibration severity of the air compressor in accordance with the method specified in GB/T 16301—2008. The vibration severity value (V.m.) of the air compressor operating under rated working conditions shall not exceed 18 mm/s.

9. Acceptance Criteria

Each air compressor shall undergo a factory test. When all inspection items of the product meet the requirements, the product shall be judged as qualified in type inspection. If any inspection item of the product fails to meet the requirements, improvement measures may be taken and the item shall be re-inspected. If it still fails to meet the requirements, the product shall be judged as unqualified in type inspection.

10. Transportation and Storage

10.1 During transportation, throwing, sliding or other methods that may cause impact shall not be adopted.

10.2 The air compressor unit shall be stored in a well-ventilated and dry warehouse. When the storage period exceeds the validity period of the oil seal, regular inspections shall be conducted, and the oil seal shall be replaced if necessary.