How much oil is there at the gas outlet of the oil-injected screw air compressor

Oil injection screw air compressor is a commonly used compressed gas equipment in the industrial field. The oil content at its gas outlet is a core indicator to measure equipment performance and gas quality. According to industry technical specifications and practical application experience, professional explanations on relevant issues are as follows:

1. Export oil content standards and scope

1. Industry benchmark
   • The oil content of the outlet compressed air of an oil-injected screw air compressor is usually controlled to3 mg/cubic meter (3 ppm)Within. This value is based on the comprehensive determination of the oil and gas separation efficiency under normal operating conditions of the equipment and the performance of the post-treatment device.
   • In special application scenarios, such as medicine, food, electronics and other industries that require extremely high gas cleanliness, the oil content needs to be further reduced to0.01 mg/mThe following are to meet oil-free or extremely low oil content needs.
2. Over-standard risk warning
   • When the oil content exceeds 3ppm, equipment failures (such as clogging of oil and gas separators), gas system pollution (such as stuck pneumatic valves) and product quality risks (such as oil residues in food and drug production) may be caused. Investigate the cause and take measures in a timely manner.

2. Analysis of factors affecting oil content

1. Impact of equipment status
   • Oil and gas separator performance: As a core oil removal component, its filter element precision, material and service life directly affect the oil content. Poor quality filter elements or filter elements that have not been replaced for a long time may lead to a decrease in separation efficiency.
   • exhaust temperature control: Excessive exhaust temperature (such as exceeding 98℃) will reduce the viscosity of the lubricating oil, weaken the oil-gas separation effect, and increase the risk of oil entrainment by the gas.
   • Oil return system operating conditions: Blocked oil return pipe, deviation in installation position or failure of oil return check valve may lead to incomplete separation of oil and gas, allowing some oil to enter compressed air.
2. Maintenance management impact
   • Filter element replacement cycle: Oil and gas separator filter elements need to be replaced regularly (usually every 4000 hours or according to differential pressure instructions). Extended use will lead to a decrease in filtration accuracy.
   • quality of lubricating oil: The use of inferior or deteriorated lubricating oil may increase the difficulty of oil volatilization and separation. Qualified oil products need to be selected according to equipment requirements.
   • Post-processing device configuration: No precision filter or dryer is configured, or the post-treatment device fails, which may prevent the oil content from being reduced to the target value.
3. Impact of operating conditions
   • Load factor fluctuations: Long-term low-load operation of the equipment may lead to insufficient lubricating oil circulation and increase the oil content in the exhaust gas.
   • ambient temperature: High temperature environment may intensify the oxidation of lubricating oil and affect the oil and gas separation effect.

3. Optimization measures for oil content control

1. Equipment selection and upgrade
   • Select high-efficiency oil and gas separators and multilayer glass fiber filter elements to improve initial separation efficiency.
   • For oil-sensitive scenarios, dual-stage precision filters can be configured (such as primary filtration accuracy of 1 micron and precision filtration accuracy of 0.01 micron) to achieve deep oil removal.
2. Operation and maintenance specifications
   • Regularly inspect and replace filter elements: Establish a filter element replacement cycle table and maintain it in a timely manner based on differential pressure monitoring data.
   • Oil return system maintenance: Regularly clean the oil return pipe to ensure that the oil return check valve functions normally to avoid oil accumulation.
   • exhaust temperature control: Optimize the cooling system (such as cleaning oil cooler fins) to keep the exhaust temperature within a reasonable range (usually 75-95℃).
3. After-processing device strengthening
   • Configure dryer: Use a freezing or adsorption dryer to reduce the dew point of compressed air and reduce the risk of oil condensation.
   • Add activated carbon filter: For extremely low oil content requirements, an activated carbon adsorption device can be added at the end of the post-treatment chain to further remove residual oil vapor.
4. Lubricating oil management
   • Select high-quality lubricating oil that matches the equipment to avoid oxidation and deterioration of the oil.
   • Regularly test the physical and chemical indicators of lubricating oil (such as viscosity and acid value) and replace deteriorated oil products in a timely manner.

4. Oil content monitoring and fault diagnosis

1. on-line monitoring technology
   • An oil content detector is used to monitor the oil content of compressed air in real time, and the data can be connected to the control system to achieve over-limit alarm.
   • Combine pressure and temperature sensors to build an equipment health management system to warn potential failures in advance.
2. Common troubleshooting
   • sudden increase in oil content: Give priority to checking whether the oil and gas separator filter element is blocked and whether the return pipe is smooth.
   • Filter element fails frequently: Evaluate the quality of lubricating oil and equipment operating conditions, and check for unfavorable factors such as high temperature and high humidity.
   • Post-processing device failure: Check the pressure difference of the precision filter and the adsorption capacity of the desiccant, and replace failed parts in time.

conclusion: The outlet oil content of oil-injected screw air compressors needs to be controlled through comprehensive measures such as equipment selection, operation maintenance and post-treatment enhancement. Users should formulate targeted management strategies based on actual working conditions to ensure that the quality of compressed air meets production needs, while reducing equipment failure rates and operating costs.