The main components and functions of the non-driven side motor assembly of the Atlas Copco oil-injected screw compressor
End cover and bearing assembly
Non-driven end cover: Fixed the motor stator, supports the bearings, seals the interior of the motor to prevent dust, moisture, etc. from entering.
Bearings: Usually use deep groove ball bearings or cylindrical roller bearings, support the non-driven end of the motor rotor to ensure coaxiality during high-speed rotation, reduce vibration and friction.
Heat dissipation structure
Some motors on the non-driven side end cover are designed with heat dissipation ribs or fan installation positions, combined with the built-in fan to form an air circulation, allowing the heat generated by the motor to be dissipated through the end cover to the environment, avoiding motor overheating.
Detection and protection elements
Temperature sensor: Embedded in the non-driven side winding or bearing area, monitors the motor temperature in real time, triggers protection and stops the machine when the temperature exceeds the limit.
Bearing vibration sensor: Equipped in some high-end models, monitors the vibration amplitude of the non-driven side bearing, predicts the wear condition of the bearing. Junction box
Some motors place the wiring box on the non-drive side, which is convenient for connecting power lines and control circuits and avoids interference with the main components such as the host piping and pulley on the drive side.
Common Faults and Causes
Excessive bearing heat or abnormal noise
The bearing lubricating grease has dried up, deteriorated, or has an improper filling amount;
The bearing is installed too tightly, with insufficient clearance, or has exceeded the tolerance for the fit with the shaft;
The rotor is unbalanced and the shaft is bent, resulting in uneven force on the bearings.
Failure of end cover sealing
The end cover sealing ring is aged or damaged;
The end cover bolts are loose, causing gaps to form, and dust and water vapor enter the motor interior.
Abnormal temperature detection
The wiring of the temperature sensor is loose or disconnected;
The sensor probe does not make good contact with the winding, causing distorted detection values.
