The crankshaft oil seal is a critical sealing component in the engine crankshaft system, mainly installed at the crankshaft output end (the "front oil seal" near the pulley) and input end (the "rear oil seal" near the flywheel). Its core function is to seal the gaps between the crankshaft and cylinder block, as well as between the crankshaft and gearbox — on one hand, it prevents engine oil leakage from the gaps, avoiding oil loss and environmental pollution; on the other hand, it blocks the intrusion of external impurities such as dust, muddy water, and metal debris, ensuring the lubrication stability of core components like crankshaft bearings and connecting rods. It serves as a "protective barrier" to prevent engine failures caused by lubrication failure.

II. Core Product Features

Superior Sealing Performance: Adopts industry-leading elastic materials such as fluoroelastomer (FKM), combined with high-precision metal skeletons to enhance structural stability. Within a wide temperature range of -40℃ to 180℃, it maintains stable sealing performance, with engine oil leakage strictly controlled.

Low-Friction and Noise-Reduction Design: The sealing lip is processed with micro-nano texture (texture depth: 5-10μm) and paired with high-temperature grease (temperature resistance ≥200℃), reducing friction resistance compared with conventional oil seals — it not only lowers the rotational energy consumption of the crankshaft but also avoids lip aging caused by frictional heat generation.

High-Precision Adaptability: The metal skeleton is formed by stamping and precision machined by CNC lathes, with dimensional tolerance controlled within ±0.02mm. It can accurately match various crankshafts with shaft diameters ranging from 30mm to 120mm (customization for non-standard sizes is available); compatible with various power systems such as diesel engines, gasoline engines, and natural gas engines, no additional adjustments to the installation structure are required, reducing adaptation costs.

III. Key Technical Parameters

IV. Applicable Industries and Application Scenarios

Commercial Vehicle Field: Designed for heavy-duty trucks (Dongfeng Tianlong, Jiefang J7, Foton Auman), light-duty trucks (Jiangling Shunda, Isuzu Qingling), and medium-duty trucks (Shaanxi Auto Delong L3000), etc. It can withstand the "continuous high temperature (crankshaft end temperature: 120-150℃)" working condition during long-distance transportation.

General Machinery Field: Can be used in fixed power equipment such as diesel generators (Yuchai YC6MK) and marine engines (Weichai WP12C). It can still maintain stable sealing during long-term continuous operation (24 hours non-stop), reducing the frequency of oil replenishment and maintenance costs.

V. Installation and Maintenance Guidelines

Pre-Installation Preparation: Clean the crankshaft journal and installation groove surface with absolute ethanol or diesel to completely remove oil stains, rust, and metal debris — residual impurities will cause early wear of the sealing lip, increasing the leakage risk by 50%; meanwhile, check if there are scratches on the crankshaft journal (scratches with depth > 0.2mm need repair) to avoid damaging the lip.

Correct Installation Method: Must use special press-fitting tools (e.g., oil seal pressure plate) to apply uniform pressure, with the press-fitting speed controlled at 5-10mm/min. Ensure the oil seal end face fits flat with the installation surface (flatness error ≤ 0.1mm); do not directly hit the oil seal edge with a hammer, otherwise, it will deform the metal skeleton and crack the rubber, leading to immediate scrapping.

Daily Inspection and Maintenance: During each engine maintenance, check if there are oil leakage traces around the oil seal edge (by observing the oil pan and flywheel housing surfaces); meanwhile, regularly check the engine oil level (it is recommended to check every 5000KM). If the oil level drops too quickly, prioritize checking whether the oil seal is leaking — early detection of leakage and replacement can avoid crankshaft bearing wear (saving 80% of maintenance costs).

Construction machinery often operates under harsh conditions including heavy dust, heavy loads and high oil temperatures, where traditional seals are prone to wear, dust intrusion and premature failure. To address these industry pain points, we provided a complete sealing solution for hydraulic systems and engines for a leading construction machinery enterprise.

Based on the actual working conditions of the equipment, we selected rubber materials with excellent high and low temperature resistance, tear resistance, oil resistance and medium resistance, and optimized the structural design to enhance dustproof and pressure-resistant performance. All products have passed a series of performance tests such as pressure resistance, wear resistance and aging resistance.

To better verify the sealing effect, we customized two structures for the client to suit their application scenarios. After repeated communication with the customer’s technical team, we finalized the plan and developed the framework and molds. On the premise of meeting working conditions, we provided two products with different materials for on-machine testing. After three months of field verification, the customer selected the more cost-effective solution.

After mass application, the sealing failure rate of the customer’s equipment was significantly reduced, downtime maintenance decreased and equipment availability greatly improved. Relying on mature customized development capabilities and stable mass production capacity, we continue to provide highly reliable sealing products for the construction machinery industry.

In response to the high performance requirements of truck wheel hub bearing oil seals in real operating conditions, our company has maintained long-term technical research and continuous product optimization. Focusing on the key indicators of starting torque and sealing stability, our technical team has carried out repeated adjustments and improvements in rubber material formulation, lip structure design, and clamping force control.

Through continuous testing, simulation verification and on-board testing, we have gradually optimized the friction performance and fitting accuracy of the oil seal. As a result, our wheel hub bearing oil seal has achieved a steady reduction in starting torque, while maintaining excellent sealing performance, wear resistance and overall operational stability. Actual test data shows that the product performs well in all key indicators.

When applied in trucks, the oil seal runs more smoothly and adapts well to frequent start-stop and long-distance driving conditions. It maintains reliable sealing performance under different working environments and effectively supports the stable operation of the wheel hub system.

With solid technical accumulation and reliable product performance, our low starting torque wheel hub oil seals have been widely recognized by customers. We continue to provide stable, high-quality sealing solutions for the commercial vehicle industry, helping customers improve the reliability and service life of their vehicle systems.