I. Core Functions of Atlas Copco Screw Air Compressor generated during the lubricating oil circulation, with a filtration accuracy typically ranging from 10 to 25 μm.
System Protection: Prevent contaminants from entering critical parts such as bearings and rotor meshing surfaces, avoiding abnormal wear, jamming or damage to seals.
Oil Quality Maintenance: Reduce the catalytic oxidation effect of contaminants on lubricating oil, delaying the deterioration rate of the oil.
II. Structure and Types of Atlas Copco Screw Air Compressor
Basic Structure
Composed of a housing (made of metal material, bearing the system oil pressure), filter element (core filtering component), and bypass valve (protection device):
Filter Element: Mostly made of folded filter paper or metal mesh, some high-end products use fiberglass composite material, intercepting impurities through micropores.
Bypass Valve: When the filter element gets clogged and the pressure difference exceeds the set value (usually 0.3-0.5 MPa), it automatically opens to ensure the lubricating oil continues to circulate (avoiding the host running out of oil), and simultaneously alerts the need to replace the filter element.
Common Types
Oil Inlet Filter: Installed at the oil pump suction port, filtering larger particle impurities in the oil tank (lower accuracy, usually 30-50 μm), protecting the oil pump.
Pressure Oil Filter: Installed on the pipeline from the oil pump outlet to the main unit, with high filtration accuracy (10-20 μm), being the main filtration stage.
Return Oil Filter: Installed in the pipeline of the oil return tank, filtering impurities from the oil returned from the main unit, preventing contamination of the oil in the tank.
III. Working Principle of Atlas Copco Screw Air Compressor
Lubricating oil is driven by the oil pump and enters the oil filter, when passing through the micro-pore channels of the filter element, impurities are intercepted on the surface or inside the filter element, and clean oil flows out from the outlet and enters the lubrication parts of the main unit. When the filter element gets clogged and the pressure difference between the inlet and outlet reaches the set value of the bypass valve (usually 0.3-0.5 MPa), the bypass valve opens, allowing the oil to directly pass through the bypass channel into the system (at this time, the oil has not passed through the filter and needs to be replaced immediately).
IV. Key Performance Indicators of Atlas Copco Screw Air Compressor
Filter Accuracy: The minimum particle diameter that can be effectively intercepted, the higher the accuracy (the smaller the value), the better the filtering effect, usually requiring ≥ 10 μm.
Pollutant Capacity: The total amount of impurities that the filter element can accommodate, the larger the capacity, the longer the service life.
Pressure Loss: The pressure loss of a new filter element should be ≤ 0.1 MPa, too high will increase the load on the oil pump and reduce the system efficiency.
Bypass Valve Opening Pressure: Needs to match the system design, too low may cause unfiltered oil to enter the main unit, too high may cause pipeline overpressure.
V. Common Faults and Maintenance of Atlas Copco Screw Air Compressor
Filter Element Blockage
Symptoms: Increased pressure difference before and after the oil filter (over 0.3 MPa), abnormal oil pressure, increased temperature of the main unit.
Reasons: Long-term lack of lubricating oil replacement, excessive dust in the environment, increased wear of the main unit resulting in a large amount of debris.
Treatment: Immediately replace the filter element, check if the oil quality has deteriorated (if necessary, change the oil), investigate the cause of the main unit wear.
Bypass Valve Failure
Harm: When the filter element is blocked, the bypass valve does not open, causing a power outage of the supply, the main unit burns out due to lack of oil; or the bypass valve opens prematurely, unfiltered oil enters the system.
Treatment: Replace the bypass valve component, regularly calibrate the opening pressure of the valve.
Leakage
Reasons: Aging sealing parts of the oil filter housing, loose installation bolts.
Treatment: Replace the sealing gasket, tighten the bolts according to the specified torque, prevent oil leakage leading to a decrease in oil level.
