Application scope of non-standard bearings for automotive tightening wheels

The non-standard bearings for automobile tightening wheels are customized bearings for special working conditions of tightening wheels (such as high load, high frequency vibration, space limitation, etc.). The size, structure, material or performance parameters are different from those of standard bearings to better match the installation requirements, transmission efficiency and reliability requirements of tightening wheels. The following is its core application scope and typical scenario analysis:

1. Passenger car field

1. Engine timing system tightening wheel

Application scenario: In the timing chain or belt transmission system of the gasoline/diesel engine, it is used to adjust the tension force of the chain/belt to prevent slipping or jumping.

Non-standard design features:

Compact structure: In response to the small space of the engine compartment, the outer diameter and width of the bearing may be reduced by 10%-20% compared to standard bearings, while maintaining the rated load capacity.

High speed adaptability: The engine speed can reach 6000-8000rpm, the bearing adopts a low-coefficient cage (such as copper alloy or polymer materials) and precision grinding raceways to reduce temperature rise and noise during high-speed operation.

High temperature resistance: When approaching the engine exhaust manifold or turbocharger, the bearings need to withstand high temperatures of 120-150℃, and special greases (such as polyurea) and heat-resistant seals (such as fluoroelastomer) are used to prevent grease loss.

2. Attachment transmission system tightening wheel

Application scenarios: In the belt transmission system that drives generators, air conditioning compressors, water pumps and other accessories, maintains the belt tension stability.

Non-standard design features:

Anti-load resistance: lateral forces may be generated during belt operation, and the bearing adopts a widened raceway or asymmetric design to improve lateral load tolerance (such as increasing from 5% rated dynamic load of standard bearings to 15%).

Dust-proof seal: There is a lot of dust and oil in the engine compartment. The bearing adopts a double-lip sealing structure (such as metal dust cover + rubber sealing lip), and the protection level is IP6X to prevent wear caused by foreign objects.

Low starting torque: To reduce the engine starting load, the bearing uses lightweight cages (such as glass fiber reinforced nylon) and low viscosity grease, and the starting torque is reduced by 20%-30% compared to standard bearings.

2. Commercial Vehicle Field

1. Heavy-duty truck engine tightening wheel

Application scenario: Diesel engine timing chain or belt transmission system, withstand higher loads and harsher working conditions.

Non-standard design features:

High load-bearing capacity: Commercial vehicles have large engine torque, the rated dynamic load of bearings is 30%-50% higher than that of passenger cars, and adopts a full-load roller design (such as cylindrical roller bearing) or reinforced cage (such as steel window type).

Impact resistance: The engine vibrates violently during the vehicle, and the bearing raceway surface is subjected to high-frequency quenching (hardness ≥60HRC) to resist impact fatigue cracks.

Long-life lubrication: Use long-acting greases (such as lithium-based composite soap + molybdenum disulfide), with a lifespan of more than 1 million kilometers, reducing maintenance frequency.

2. Tightening wheel for bus air conditioner compressor

Application scenario: In the belt transmission of large passenger bus air conditioning systems, adjust the tension force of the compressor belt.

Non-standard design features:

Large-size design: The passenger bus air conditioner compressor has a large power, the belt width can reach more than 50mm, and the outer diameter of the bearing may exceed 100mm. Non-standard sizes need to be customized to match the tightening wheel arm.

Low temperature resistance: The temperature in northern regions is as low as -40℃ in winter, and bearing greases must have good low temperature fluidity (such as the freezing point ≤-50℃) to prevent dry friction during startup.

Low noise: The internal noise requirements of passenger cars are strictly required. The bearings adopt super-fine grinding raceways (surface roughness Ra≤0.05μm) and low-noise cages, and the operating noise is ≤55dB (A).

3. New energy vehicle field

1. Electric compressor tightening wheel

Application scenario: In the heat pump and air conditioning system of new energy vehicle, the belt or chain transmission of the electric compressor is driven.

Non-standard design features:

High efficiency: Electric vehicles are sensitive to energy consumption, and the bearings adopt a low friction design (such as ceramic balls or polymer cages), which reduces transmission losses and improves system efficiency by 3%-5%.

Electromagnetic compatibility: Avoid electrical corrosion caused by induced current from bearing materials, use non-magnetic cages (such as stainless steel) or insulating coatings (such as aluminum oxide).

Lightweight: In order to reduce the weight of the vehicle, the bearings are designed with aluminum alloy cages or hollow rollers, and the weight is reduced by 15%-20% compared to standard bearings.

2. Hydrogen fuel cell air compressor tightening wheel

Application scenario: In the hydrogen fuel cell vehicle air supply system, the belt transmission of the air compressor is driven.

Non-standard design features:

Hydrogen-resistant environment: Hydrogen may penetrate into the bearing and cause grease failure. It requires hydrogen-compatible materials (such as stainless steel cages) and sealing structures (such as laser welding seals).

High-speed stability: The air compressor speed can reach more than 100,000 rpm. The bearing adopts aerodynamic optimization design (such as raceway inclination adjustment) and ceramic hybrid bearings (steel + ceramic balls) to reduce high-speed vibration.

Long life: The life of the fuel cell system requires ≥5000 hours, and the bearings achieve ultra-long life through surface plating (such as DLC) and special greases (such as perfluoropolyether).