The difference between oilless screw air compressor and oil-free air compressor

The difference between oil-free screw air compressor and oil-free air compressor is mainly reflected in the following aspects:

1. Working principle

1. Oil-free screw air compressor:
   • Luction and cooling: During the compression process, lubricating oil participates in the compression, playing the role of lubricating the running components in the main machine, and at the same time takes away the high temperature caused by compression and helps dissipate heat.
   • Oil and Gas Separation: The compressed oil and gas mixture will be separated in the oil and gas separation barrel. After the separated compressed air is recovered through the secondary return pipe, its oil content will be less than 5PPM (i.e., a micro-oil screw air compressor).
2. Oil-free screw air compressor:
   • Oil-free compression: During the compression process, no oil participates in the compression of the air. Special temperature-resistant materials such as molybdenum disulfide or Teflon are used on the screw to overcome the high temperatures generated during compression rather than oil.
   • Bearing Lubrication: Although the main bearing also requires cooling and lubrication, this part of the lubrication is separated from the compression process and will not affect the purity of the compressed air.

2. Gas purity

1. Oil-containing screw air compressors:
   • Oil content: Since lubricating oil participates in the compression process, the compressed air output contains a certain amount of oil, which is suitable for industries with no strict requirements on air.
2. Oil-free screw air compressor:
   • Oil-free pollution: The compressed air output is oil-free and has high purity. It is especially suitable for occasions with high requirements for gas quality, such as food and pharmaceutical production.

3. Maintenance and use cost

1. Oiled screw air compressor:
   • Lugrain oil replacement: lubricant needs to be replaced regularly, which increases maintenance cost.
   • Oil product requirements: The quality requirements for lubricating oil are high, otherwise it will affect the performance of the equipment.
   • Using Cost: The technology is mature, the production cost is low, and the market price is relatively affordable.
2. Oil-free screw air compressor:
   • No lubricant required: There is no need to change lubricant regularly, reducing operating costs.
   • Simple maintenance: Due to the oil-free design, failures caused by oil pollution are reduced, and the maintenance cost is relatively low.
   • Using Cost: Due to higher technical and material requirements, initial investment will be relatively large.

4. Performance characteristics

1. Oiled screw air compressor:
   • Good lubricating performance: Lubricating oil can effectively reduce mechanical wear and extend service life.
   • Good sealing performance: Lubricating oil can effectively reduce gas leakage and improve compression efficiency.
   • Noise Level: The noise level is relatively low due to the buffering effect of lubricating oil.
2. Oil-free screw air compressor:
   • Environmental and energy-saving: The oil-free design reduces the use of lubricating oil, does not produce waste oil, and is environmentally friendly.
   • Compact structure: It is usually a simpler design, small in size and light in weight, making it easy to install and move.
   • Noise Level: Although an oil-free design may increase friction between mechanical components, the noise level can also be controlled at a lower range by optimizing the design and adopting noise reduction measures.

5. Scope of application

1. Oiled screw air compressor:
   • General industrial applications: Due to its lubrication system, it is suitable for continuous high-strength work or large-scale industrial facilities.
   • Occasions where air requirements are not strict: such as steel, electricity, hardware, mining, ceramics, textiles, machinery and other industries.
2. Oil-free screw air compressor:
   • High-quality air requirements: industries such as food, pharmaceuticals, and medical care that require high compressed air quality.
   • Precision manufacturing or experimentEnvironment: In the event of lubricant contamination, it is necessary to avoid.

6. Other precautions

1. Heat dissipation problems of oil-free screw air compressors:
   • Due to the oil-free screw air compressors working at high loads, the heat dissipation effect may not be as good as oil-free air compressors. Therefore, it is necessary to pay attention to the temperature control of the use environment to ensure the normal operation of the equipment.
2. Technical Challenges of Oil-free Screw Air Compressors:
   • Oil-free Screw Air Compressors need to use special high-temperature resistant materials to solve the high temperature problems during the compression process, and it is necessary to ensure that the lubricating space of the rotor bearing and the compression space of the rotor are sealed with each other. This increases the processing accuracy and cost of the equipment, and also places higher requirements for maintenance.

In general, oil-free screw air compressors and oil-free screw air compressors have their own advantages and disadvantages. When choosing, users should comprehensively consider factors such as equipment performance, operating costs, and maintenance based on actual needs. For occasions such as pharmaceutical companies that require high compressed air quality, an oil-free screw air compressor is undoubtedly a more suitable choice.