Air compressor oil is formulated with highly refined paraffinic base oils and high performance additives to deliver superior lubrication across various rotary and reciprocating air compressors. Within a rotary screw air compressor system, air compressor oil fulfills several vital functions: it lubricates moving parts, creates a tight seal between rotors to trap air, prevents premature component wear, and helps cool air during compression.

WHY DO PORTABLE SCREW AIR COMPRESSORS NEED OIL? Features and Benefits

Air compressor oil is engineered to provide an extended service life across most compressor applications. The thermal stability and oxidation resistance of these fluids help maintain cleaner compressors, allowing longer operating intervals between scheduled maintenance and routine oil changes. In addition, outstanding anti-wear and corrosion protection helps prolong equipment life while reducing overall maintenance requirements.

WHAT KIND OF OIL DOES AN AIR COMPRESSOR TAKE?

- Always ensure you use the recommended oil listed below
- Oil viscosity varies depending on operating temperature and other environmental conditions.
- Even continuous oil replenishment cannot restore degraded fluid condition; always change the oil completely at every scheduled interval.
- Avoid mixing with other oil brands, as this degrades performance and shortens compressor oil service life (though fresh compressor oil can tolerate a small mixture from different brands).
- Operating the unit with old and deteriorated compressor oil causes bearing damage or severe hazards like ignition in a separator receiver tank; always change the oil completely at every scheduled interval.
- Adhere strictly to designated regulations when disposing of compressor oil.
- Select an appropriate lubricant from the recommended oils listed below.

Selection table

Remarks: Selecting the right compressor oil primarily depends on operating rotation speed, pressure, and temperature. Higher rotation speeds require lower viscosity oil, whereas lower rotation speeds require higher viscosity oil to maintain proper lubrication and sealing.

Selection for high discharge pressure and discharge temperature

High-pressure mobile air compressors require 46# or 68# synthetic oil. The typical viscosity index is 130 for synthetic oil and 110 for mineral oil. At high temperatures, synthetic oil delivers significantly better performance. If mineral oil is selected, choose 68#. Synthetic oil 46# maintains a viscosity grade similar to 68# at high temperatures of 100-120°C, whereas the viscosity grade of mineral oil drops significantly under high heat. In compressors operating under high pressures within 30bar where shear forces are elevated, 68# oil thins at high temperatures but still reliably maintains essential air tightness. The maximum viscosity for a screw compressor should never exceed 68#. When the exhaust temperature of the mobile air compressor exceeds 120℃, mineral oil cannot be used, and silicone oil or another suitable oil must be selected, as excessive temperatures can trigger deflagration or flash combustion. For working pressures within 24bar, you can select 68# mineral oil or 46# synthetic oil; for 30-40bar, operate with 68#.

Selection and solutions for low temperature and alpine regions:

In alpine regions, the customized lubricant model is ACLP 70SP#46, rated for -25°C with a pour point at -40°C, though low-temperature fluidity remains limited. During cold winter periods, 32# oil should be used, whereas 46# oil should replace it in summer. Operational risks are higher in northern climates because although the base oil is identical, the viscosity behavior differs. Be sure to replace all aging oil and avoid leaving any aged oil behind, as residual old oil accelerates the degradation of new oil. In low-temperature environments, the viscosity grade should be reduced or specially customized; otherwise, 32# oil must be used because 46# oil may prevent the air compressor from starting normally. Most compressor oils struggle during cold starts, and excessive viscosity can halt oil flow entirely. Therefore, exercise great caution when selecting winter oil, as poor fluidity can quickly cause the airend to seize or get stuck. If overheated at high temperatures, internal parts can stick together; however, installing a pre-heater device reliably solves this issue.

HOW DO I CHECK THE AIR COMPRESSOR OIL LEVEL?

You should check your air compressor oil level daily or before each compressor operation. Follow these simple steps to verify the oil level:

Place the unit on level ground and shut down the air compressor, ensuring the machine has fully cooled before checking the oil level.

Check the compressor oil level. The correct oil level sits between the upper and lower limits on the gauge while the unit is stopped. If the sight gauge shows below the midpoint, replenish the oil promptly.

HOW TO CHANGE AIR COMPRESSOR OIL?

When it is time to change your air compressor oil, always follow the maintenance instructions in your air compressor manual.

Note:

When refilling the separator receiver tank with compressor oil, stop the engine, confirm that the pressure gauge reads 0 psi (0 bar) with no residual pressure remaining, and then gradually loosen the oil filler cap to refill oil.
Note that residual pressure in the receiver tank can cause extremely hot compressed air and oil to shoot out, which may cause scalding or severe injury.

You can purchase air compressor oil directly from Awvgpower or an authorized Awvgpower dealer.
In addition, you can consult our selection standards to strictly choose an equivalent air compressor oil.