An oil-injected screw air compressor, also known as an oil-flooded screw compressor, is a type of positive displacement air compressor that uses a pair of helical screws to compress air. This type of compressor is widely used in various industries to provide a continuous supply of compressed air for a range of applications, from manufacturing and construction to automotive and more. The “oil-injected” aspect of the design refers to the presence of oil within the compression chamber, which serves multiple purposes in the compressor’s operation.
Key Components and Working Principle:
Screw Elements: The core components of an oil-injected screw compressor are the two interlocking screw elements. These screws, usually referred to as the “male” and “female” rotors, have specially designed helical profiles that engage with each other as they rotate.
Compression Chamber: The screw elements are housed within a compression chamber. As the rotors rotate, the space between the screw profiles gradually reduces, causing the air to be trapped and compressed within the chamber.
Oil Injection: One of the distinctive features of oil-injected screw compressors is the injection of oil into the compression chamber. The injected oil serves several purposes:
Lubrication: The oil lubricates the moving parts, including the screw elements and bearings, reducing friction and wear.
Cooling: The oil absorbs heat generated during compression, helping to maintain stable operating temperatures.
Sealing: The oil forms a thin film between the rotors, creating a seal that prevents air leakage between the screw profiles.
Cleaning: The oil captures contaminants and particulates from the compressed air, aiding in filtration.
Air Inlet and Outlet: Atmospheric air is drawn into the compressor through the air inlet. After compression, the compressed air is discharged through the outlet.
Belt Driven Screw Air Compressor
Working Process:
Air Intake: Atmospheric air is drawn into the compressor through the air inlet. The air contains moisture and contaminants that are present in the ambient environment.
Compression: As the rotors rotate, the air is trapped in the spaces between the screw profiles. As the screw elements continue to rotate, the volume between the profiles reduces, causing the air to be compressed.
Oil Injection: Oil is injected into the compression chamber. The injected oil serves as a lubricant, coolant, and sealant. It mixes with the compressed air and captures contaminants.
Oil Separation: After compression, the air-oil mixture enters a separator element or a series of separation stages. These stages are designed to separate the oil from the compressed air.
Oil Filtration: The separated oil is typically filtered to remove any remaining contaminants before being recirculated back into the compression chamber. The filtered oil also lubricates the bearings and other moving parts.
Compressed Air Outlet: The cleaned and compressed air exits the compressor through the air outlet. The compressed air is now ready for use in various applications.
Advantages of Oil-Injected Screw Compressors:
High Efficiency: Oil-injected screw compressors are known for their high efficiency and consistent air output.
Continuous Operation: They are designed for continuous operation, making them suitable for applications with high air demand.
Smooth Operation: The presence of oil ensures smooth and quiet operation, reducing vibrations and noise levels.
Cooling and Lubrication: Oil injection provides efficient cooling and lubrication for the compressor’s internal components, prolonging their lifespan.
High Pressures: Oil-injected screw compressors are capable of delivering high air pressures, making them suitable for various industrial and commercial applications.
Easy Maintenance: Regular oil changes and maintenance help ensure the compressor’s performance and longevity.
Oil-injected screw compressors are versatile tools that provide reliable and efficient compressed air for various industries. However, they require proper maintenance, including monitoring oil levels and ensuring proper filtration, to ensure optimal performance and minimize contamination risks in the compressed air output.