1. Single-screw water-lubricated oil-free air compressors use pure water for lubrication and cooling. The internal components are made of medical-grade stainless steel, ensuring they will never corrode. Dry oil-free air compressors still rely on lubricating oil for cooling, resulting in an oily smell.
2. Pure water circulates continuously within the water-lubricated air compressor system, automatically changing the water at set intervals to ensure water quality. The operating temperature does not exceed 50 degrees Celsius, thus preventing scale buildup. Dry oil-free compressors operate at temperatures as high as 200 degrees Celsius, severely impacting the lifespan of the cooling oil and bearings.
3. Single-screw water-lubricated oil-free air compressors use imported special bearings, which can be lubricated with water, resulting in high efficiency, low noise, and fewer bearing combinations. Twin-screw air compressors generally use FAG or SKF bearings, which have shorter lifespans, higher noise levels, and require various bearing combinations.
4. Single-screw water-lubricated air compressors spray pure water directly into the machine body. Because water has a high specific heat value, the compression chamber operates almost under isothermal compression, resulting in lower energy consumption. Dry oil-free compressors use cooling oil at around 100 degrees Celsius, while the compression chamber temperature exceeds 200 degrees Celsius. This significant temperature difference leads to higher energy consumption.
5. Single-screw water-lubricated oil-free compressors have a direct connection between the machine body and motor, operating at speeds as low as 3000 rpm. They lack speed-increasing gears, resulting in long bearing life and low maintenance costs. Dry oil-free compressors operate at speeds above 18000 rpm, requiring gears between the machine body and motor, leading to shorter bearing life and higher maintenance costs.
6. Water-lubricated air compressors use water to cool and lubricate the seals, ensuring air quality. They operate at around 3000 rpm, with temperatures around 55 degrees Celsius, resulting in low maintenance costs. Dry twin-screw air compressors use oil-cooled bearings, compromising air quality. Secondary compression speeds reach approximately 18,000 rpm, with temperatures reaching around 200 degrees Celsius, posing safety risks and increasing maintenance costs.