The maintenance of third-generation automotive wheel hub bearings (designed with bearing units and anti lock braking systems, with the inner flange fixed to the drive shaft and the outer flange integrated installation) should focus on four core aspects: installation specifications, cleaning and protection, lubrication management, and professional inspection. The specific methods are as follows:. When pressing in, it is necessary to ensure that the outer ring end face is completely pressed against the outer shell shoulder end face, and the inner ring end face is completely pressed against the shaft shoulder end face to avoid additional loads caused by gaps, which may increase noise or cause premature damage.
Directional installation of magnetic thrust ring
Bearings equipped with ABS devices, with magnetic thrust rings inside the sealing ring, must be kept away from magnetic fields (such as electric motors and power tools) before installation.
.Test the magnetic direction by placing a light object (such as iron filings) near the edge of the bearing. During installation, point the side with the magnetic thrust ring inward, facing the ABS sensitive component, to prevent the brake system from malfunctioning.
.Axis alignment calibration
After installation, it is necessary to check whether the bearing axis coincides with the axis of the housing hole. Deviation from the design accuracy will cause additional loads on the rolling surface and accelerate wear.
.2. Cleaning and protection: prevent pollutants from entering
Storage and transportation environment control
Bearing components need to be kept clean during storage and transportation to avoid dust and sediment from entering.
. If the packaging is damaged or has been waiting for too long, it needs to be cleaned again before installation.Regular deep cleaning
When disassembling bearings, soak them in kerosene or gasoline for cleaning, and gently brush the gaps with a soft bristled brush to avoid scratching the sealing ring or raceway with sharp tools.
. After cleaning, use a clean cloth to wipe dry to prevent moisture residue from causing rust. Sealing ring protectionIt is strictly prohibited to disassemble the wheel hub bearing unit or adjust the sealing ring, otherwise water and dust may enter, causing damage to the sealing ring and inner race raceway, resulting in permanent bearing failure.
.III. Lubrication Management: Extend Service Life
Selection and Addition of Lubricating Greases
Choose lubricating grease with excellent high temperature resistance, wear resistance, and waterproof performance, evenly covering the rolling elements, cage, and inner and outer rings.
.The filling amount should be moderate. Too much can cause high operating temperatures, while too little cannot provide sufficient protection.
. The general experience is that the total amount of grease accounts for 50% of the bearing clearance.Regular replacement cycle
Non sealed bearings (such as double row tapered roller bearings) need to have their lubricating grease replaced every 20000 to 30000 kilometers of driving.
; If there is no leakage in the sealed bearing, there is no need to add oil throughout its entire lifespan.Lock nut torque control
When installing the lock nut, it is necessary to refer to the torque value specified in the vehicle manual to avoid poor bearing fit caused by over tightening or over loosening.
.Fourth, professional inspection: prevent early failure
Daily monitoring indicators
Abnormal noise detection: If you hear a buzzing or creaking sound from the wheel during driving, it may be a signal of bearing wear and should be checked immediately.
.Temperature detection: The wheel hub feels abnormally hot when touched by hand, which may be due to insufficient lubrication or damaged bearings, and further investigation is needed.
.Vibration detection: Obvious vibration during high-speed driving may be a sign of bearing imbalance or damage.
.Regular in-depth inspection
Check the bearings every six months or every 10000 kilometers, with a focus on observing whether there is peeling or pitting on the inner and outer raceway surfaces of the bearings.
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Whether the rolling elements and the cage are worn;
;Whether there are cracks or fatigue peeling in the bearing and bearing seat ring;
;Is the clearance between the inner diameter of the bearing and the shaft neck ≤ 0.10mm (measured vertically above and below the ground).
Pair replacement principle
Due to similar working conditions, even if only one is damaged, it is recommended to replace the front wheel hub bearings in pairs to avoid secondary failures caused by uneven force on both sides.
.Fifth, taboos: avoid human damage
Overloading and aggressive driving are prohibited
Overloading will increase bearing load and accelerate wear and tear;
; Sudden braking and turning can cause impact force, leading to bearing damage.Tire pressure management
Tire pressure that is too high or too low can affect the bearing capacity of the wheel hub and axle, and should be regularly checked and adjusted to the standard value.
.Brake system linkage inspection
When replacing the brake system, it is necessary to simultaneously check the bearings and replace the oil seals to prevent oil leakage from contaminating the bearings.
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