Spherical roller bearings for fans are widely used in key parts such as fan shafts and gearboxes due to their automatic centering ability, high load-bearing performance, and adaptability to complex working conditions. To ensure its long-term stable operation, strict control is required in terms of installation, lubrication, maintenance, and environmental adaptation. Here are specific usage precautions:
1. Installation and commissioning precautions
Strictly check the accuracy of the installation surface
Shaft and bearing seat: The roughness of the installation surface should be ≤ Ra1.6 μ m, and the cylindricity error should be ≤ 0.01mm to avoid bearing bias or vibration caused by uneven surfaces.
Alignment requirement: The alignment error between the fan main shaft and the gearbox shaft should be controlled within 0.05mm to prevent the self-aligning roller bearing from accelerating wear due to additional stress.
.Control installation force and sequence
Heating installation: If the hot installation method is used, the bearing heating temperature should be controlled at 80-100 ℃ (to avoid material annealing caused by exceeding 120 ℃), and an electromagnetic induction heater should be used for uniform heating to prevent local overheating.
.Installation sequence: First install the inner ring of the bearing onto the shaft, then install the outer ring onto the bearing seat, avoiding direct tapping on the bearing cage or rolling elements.
.Pre tightening force adjustment
Cone hole bearing: Adjust the pre tightening force through the axial nut to ensure that the clearance is within the range of 0.05-0.15mm (refer to the bearing manual for details), to avoid vibration caused by excessive clearance or heat caused by insufficient clearance.
. Cylindrical bore bearings: No pre tightening is required, but the axial positioning needs to be checked for reliability.II. Lubrication and Sealing Management
Lubricant Selection
Oil Lubrication: Use extreme pressure anti-wear lithium based grease (such as NLGI No. 2) with a drop point of ≥ 200 ℃ and a suitable temperature range of -30 ℃ to+150 ℃.
.Oil lubrication: If a circulating oil system is used, ISO VG32 or VG46 turbine oil should be used, and the oil temperature should be controlled at 40-60 ℃ (to avoid excessive oil temperature causing lubrication failure).
Lubrication controlOil filling amount: The initial filling amount is 1/3 to 1/2 of the bearing cavity, and it should be replenished to 2/3 after 500 hours of operation to avoid excessive temperature rise.
. Oil lubrication system: It is necessary to regularly check the oil level and quality, replace the lubricating oil every 3000 hours, and clean the oil circuit.Sealing and Protection
Dustproof Sealing: Adopting a double lip fluororubber sealing ring, combined with a labyrinth sealing structure, to prevent dust and water vapor from entering the interior of the bearing.
. Regular inspection: Check the wear of the sealing ring every 2000 hours of operation, and replace it immediately if aging or damage is found.III. Operation Monitoring and Maintenance
Temperature Monitoring
Bearing Temperature Rise: During the initial operation, the temperature rise should be ≤ 30 ℃ (compared to the ambient temperature), and after stabilization, the temperature should be ≤ 80 ℃.
. If the temperature rises above 50 ℃ or continues to rise, the machine should be stopped immediately for inspection. Infrared thermometer: Regularly use an infrared thermometer to detect the temperature of the outer ring of the bearing, and combine vibration analysis to determine the operating status.Vibration Analysis
Vibration Threshold: The effective value of the vibration velocity of the fan bearing is ≤ 4.5mm/s (ISO 10816-3 standard). If it exceeds this value, further analysis is needed to determine whether it is a bearing failure (such as peeling off of the raceway or damage to the cage).
. Spectrum analysis: By using a vibration spectrometer to detect high-frequency components (such as above 1000Hz), it is determined whether there is poor lubrication or pitting problems.Regular maintenance
Cleaning cycle: Clean the oil and dust on the surface of the bearing every 5000 hours of operation to prevent impurities from entering the lubrication system.
. Clearance inspection: Use a feeler gauge or dial gauge to check the bearing clearance. If the clearance exceeds twice the initial value, the bearing needs to be replaced.IV. Environmental Adaptability Requirements
Anti corrosion Measures
Coastal or humid environments: Apply rust proof oil to the outer ring of the bearing, or use stainless steel material for the cage.
. Chemical corrosion environment: Avoid using sulfur-containing grease and use chemical resistant fluororubber sealing rings instead.Anti impact design
Fan start stop impact: Optimize the fan start stop curve to avoid bearing overload caused by rapid acceleration or deceleration.
.Installing shock absorbers: Install rubber shock absorbers between the bearing seat and the foundation to reduce vibration transmission.
. Extreme temperature responseLow temperature start-up: In an environment below -20 ℃, the bearing needs to be preheated to above 0 ℃ before starting to prevent dry friction caused by grease solidification.
. High temperature operation: If the ambient temperature exceeds 50 ℃, it is necessary to strengthen ventilation and heat dissipation or adopt a forced cooling system.