@Air Compressor
2025-03-27
Executive standard for special oil for air compressor
Detailed explanation of the executive standard for special oil for air compressors
The selection of special oil for air compressors must comply with strict national and international standards to ensure efficient and safe operation of the equipment. The following will systematically sort out you from four aspects: standard system, performance indicators, certification requirements and selection specifications:
1. Domestic implementation standards
- reciprocating air compressor
- standard number：GB 12691-90
- classification：
- L-DAA(Light load): Mineral oil base, suitable for low pressure air compressors with exhaust temperature ≤80℃.
- L-DAB(Medium load): Improved mineral oil, suitable for medium pressure air compressors with exhaust temperatures of 80-180℃.
- viscosity grade: 32, 46, 68, 100, 150, selected based on ambient temperature and compressor load.
- rotary air compressor
- standard number: GB5904 -86 (light load injection rotary type)
- classification: L-DAG, suitable for oil-sprayed screw or sliding vane air compressors.
- viscosity grade: 15, 22, 32, 46, 69, 100, low-viscosity oils can reduce energy consumption.
- Special oil for screw air compressor
- standard type: Enterprise standards (such as L-DAH)
- characteristics: Adopt hydrogenated base oil, with strong resistance to high temperature oxidation, including 32 and 46 conventional grades and 32A and 46A anti-wear types.
2. International common standards
- ISO 8573-1
- Define compressed air quality levels, the oil content classification is as follows:
- oil-free：≤0.01 mg/m³
- low oil：≤0.1 mg/m³
- conventional：≤1 mg/m³
- Clean fields such as pharmaceuticals and electronicsClass 1 (≤0.1 mg/m³) standard must be met.
- Germany DIN 51506
- classification: VB/VC (light load), VBL/VCL (medium load), VDL (heavy load).
- characteristics: Emphasize oxidation resistance and carbon deposition resistance, suitable for high-pressure and high-temperature working conditions.
3. Core performance indicators
| indicators | Requirements and significance |
|---|---|
| Viscosity (40℃) | – Screw machines are commonly used No. 46, and No. 32 is used in low-temperature environments; the oil needs to be changed if the viscosity changes by ±15%. – Affects oil film formation and sealing effect. |
| flash point | ≥180℃ to prevent spontaneous combustion of oil at high temperatures. |
| oxidation resistance | Inhibiting acid value increase and sludge formation caused by oxidation, and extending oil change cycles. |
| anti-emulsification | Quickly separate when encountering water to prevent emulsion from corroding equipment. |
| pour point | ≤-10℃ to ensure smooth low-temperature start-up. |
| acid value | New oil is ≤0.09, and old oil exceeds 0.5 and needs to be replaced, reflecting the degree of oil deterioration. |
4. Certification and selection specifications
- certification requirements
- Priority choice passesISO 8573-1Certified oil products comply with international quality grading.
- The food and pharmaceutical industries need to meet additional requirementsNSF H1Food grade certification.
- selection principle
- compressor type: Select L-DAA/B for reciprocating machines, and select L-DAH or synthetic oil for screw machines.
- Condition matching: Synthetic oil is used in high temperature environments (>80℃); anti-emulsification needs to be strengthened in high humidity environments.
- Viscosity selection: Refer to the compressor manual and adjust it in conjunction with the ambient temperature.
- Oil change index
- Black color、Viscosity exceeds standard、Acid value>0.5、Pentane insoluble matter>0.5%Need to be replaced immediately.
5. Application scenario suggestions
- general industrial: L-DAA/B (reciprocating machine), L-DAG (screw machine), meet GB standards.
- Severe working conditions: Choose synthetic oil or L-DAH anti-wear type to improve oxidation resistance and equipment life.
- Clean field: Equipped with a multi-stage filtration system to ensure ISO 8573-1 Class 1 oil rating.
summary: Special oil for air compressors must strictly comply with domestic standards (GB series) and international standards (ISO 8573-1). Its core performance indicators include viscosity, flash point, oxidation resistance, etc. When selecting, the compressor type, working environment and certification requirements should be comprehensively considered, and the oil condition should be regularly tested to extend equipment life.