@air
2025-04-17
What is the oil content at the export of oil-bearing screw machine
The outlet oil content of oil-carrying screw machines (oil-injected screw compressors) is usually controlled to2-3ppmBelow (i.e. 2-3 mg/cubic meter), this standard is based on measurements under normal operating conditions. The following is a detailed explanation:
1. Oil content standard
- industry standards
- After the oil-injected screw compressor has been separated from oil and gas, the residual amount of compressed air at the outlet shall not exceed3ppm。If this value is exceeded, it may contaminate subsequent equipment or affect product quality.
- influencing factors
- equipment design: The type (such as centrifugal, condensing) and material of the oil and gas separator directly affect the separation efficiency.
- operating conditions: Insufficient exhaust pressure and overload and low pressure use may lead to an increase in the concentration of oil mist and increase the difficulty of separation.
- maintenance state: Aging of lubricating oil, clogging of return pipes or failure of check valves will significantly affect the oil content at the outlet.
2. Detection and judgment methods
- sampling and observation method
- Use paper cups or glass to sample samples. If there are only scattered oil stains on the water surface, it is normal; if oil-water stratification occurs, it means that the oil content exceeds the standard.
- system inspection method
- check item：
- Whether the oil level is too high and whether the lubricating oil is contaminated.
- Whether the return line is blocked, eccentric or too short.
- Whether the check valve is stuck or reversed.
- Whether the guide hood and filter element of the oil and gas separator are damaged.
- instrumental testing
- Use high-precision oil content tester (such as infrared spectrometer, gas chromatograph), and the measurement accuracy can reach0.003mg/m³。
3. Reasons for exceeding the standard and solutions
| the causes of exceeding standards | solutions |
|---|---|
| Oil and gas separator is blocked or damaged | Replace the separator filter element and clean the inside of the separator |
| Inproperly installed or blocked return line | Adjust the height of the oil return pipe (1-2mm from the bottom of the oil separator) and clean up blockages |
| Check valve failure | Inspect and replace damaged check valves |
| Excessive or contaminated lubricating oil | Adjust the oil level and replace with new lubricating oil |
| Insufficient exhaust pressure | Contact the manufacturer to adjust equipment parameters or replace suitable oil products |
4. Industry application suggestions
- key scenes
- In sensitive industries such as food and medicine, it is recommended to increaseactive carbon adsorption tankorEfficient coalescing filter, further reduce the oil vapor content to0.2mg/m³Below.
- maintenance strategy
- regular maintenance: Replace lubricating oil and oil separator filter elements every 2000 hours.
- on-line monitoring: Install an oil content sensor to provide real-time warning of the risk of exceeding the standard.
- equipment selection
- High pressure ratio working conditions (such as above 35MPa) need to be selectedMulti-stage compression + efficient condensation separationSystem to avoid residual oil vapor.
summary
The oil content at the outlet of oil-bearing screw mills must be strictly controlled below 3ppm. Through standardized testing, system maintenance and equipment upgrades, the cleanliness and safety of compressed gas can be ensured. For special industries, it is recommended to adopt stricter oil control plans.
