Hebei Hankai rear hub oil seal
2. Protecting Against Contamination Wheel oil seals act as barriers against external contaminants. Dust, dirt, and moisture can enter wheel assemblies if seals fail, leading to corrosion and degradation of components. Keeping these harmful agents at bay is essential for maintaining the health of the vehicle.
wheel oil seal

2. Contaminant Protection Grease seals act as a first line of defense against contaminants. Dust, water, and debris can enter the bearing assembly and potentially lead to corrosion, pitting, and other forms of wear. By keeping these contaminants out, grease seals help maintain the integrity of the bearings.
wheel bearing grease seal

The outer part of an oil seal is made of metal or rubber, depending on the intended application. Metal-cased seals are a cost-effective option used when the housing bore is made of the same material, allowing for equal expansion and contraction of the materials during use. Rubber-cased oil seals provide a tight fit and are commonly used when metal-cased seals have the potential to fail. They are corrosion-resistant and capable of withstanding extreme temperatures and pressures.