Differences In Maintenance Characteristics Between Oil-free Screw Compressors And Oil-Lubricated Screw Compressors

There are significant differences in maintenance characteristics between oil-free screw compressors and oil-lubricated screw compressors. The maintenance advantages of oil-free screw compressors are mainly reflected in the following aspects, which are especially suitable for scenarios with high requirements for cleanliness and operating stability:

1. Reduce oil-related maintenance

No need to regularly replace lubricating
oil and filter element Oil-lubricated screw machines require regular replacement of lubricating oil (usually every 1000-4000 hours), and consumables such as oil filters and oil-gas separator filter elements need to be replaced at the same time. The maintenance process is cumbersome and costly.
Since the oil-free screw machine has no lubricating oil system, it completely eliminates the steps of changing oil, cleaning the oil circuit, and replacing the oil filter, greatly simplifying the maintenance process.

Avoid additional maintenance caused by oil contamination.
Oil-lubricated screw compressors may contain oil in the compressed air due to oil-gas separator failure, oil line leakage and other problems, requiring shutdown to check leaks, replace seals or separators, and may even contaminate downstream equipment (such as pneumatic components and pipelines), causing secondary maintenance.
Oil-free screw compressors eliminate the risk of oil contamination from the root, reducing sudden shutdowns and additional maintenance caused by oil problems.

2. Longer maintenance cycles and less downtime

• The core components of oil-free screw compressors (such as rotors and bearings) usually use wear-resistant coatings, self-lubricating materials or independent grease lubrication systems (non-contact compression chambers), which have lower wear rates and longer maintenance intervals (some brands can reach 8,000-15,000 hours).
• Oil-lubricated screw compressors require more frequent shutdowns for maintenance because the performance of the lubricant decreases over time. Especially under high temperature and high load conditions, the maintenance cycle may be further shortened, affecting production continuity.

3. Reduce maintenance costs

Lower consumables cost
Oil-free screw compressors do not need to purchase lubricating oil, oil filters, oil-gas separators and other consumables, which can save a lot of procurement costs in the long run.
The lubricating oil and related filter elements of oil-lubricated screw compressors are continuous consumables, and the accumulated cost is relatively high (especially for large units or high operating time scenarios).

Reduced labor costs
The maintenance steps of oil-free screw compressors are simple (such as regular cleaning of air filters and checking of cooling systems), and the labor time and technical threshold required are lower; while the oil-lubricated screw compressors’ oil change, oil circuit cleaning and other tasks take a long time and require professional operation to avoid failures caused by misoperation.

4. Adapting to more stringent environmental and industry demands

• In industries such as food, medicine, and electronics that have extremely high requirements for compressed air cleanliness, oil-lubricated screw compressors still have the risk of oil residue even if they are equipped with precision filtration equipment, and additional investment is required to maintain the filtration system.
  Oil-free screw compressors can directly provide oil-free compressed air without the need to add maintenance steps for “oil removal”, which is more in line with industry compliance requirements and indirectly reduces maintenance pressure caused by compliance issues.

Summary: The core advantages of oil-free screw compressor maintenance

The maintenance advantages of oil-free screw compressors make them more competitive in the pursuit of high efficiency, cleanliness, and low maintenance burden, especially suitable for long-term continuous operation and downtime-sensitive industrial environments. However, it should be noted that the initial purchase cost of oil-free screw compressors is usually high, and a comprehensive evaluation based on actual working conditions is required.