In addition to their practicality, hammer head T bolts are also known for their durability
Figure 1: O.D. (outside diameter) wall material
Significance of Oil Seal Wheel Hub in Vehicle Maintenance


Finding oil spots under a parked vehicle can be both worrying and stressful for any vehicle owner. If the seal’s leak is small, oil may start to accumulate on the underside of the engine. But as the leak gets bigger, the oil leak will become visible in the front side of the engine.
The edge of the metal is finely ground after seal manufacture in a centerless grinder to enable an interference fit in the oil seal housing. A slight chamfer on the outer diameter (OD) of the seal is desirable for easy assembly. The sealing lip is prepared by buffing, grinding or cutting away the rubber flash which occurs at the sealing edge. A fine sealing edge creates sufficient pressure on the shaft to minimise spring load, leading to lower friction whilst maintaining effective seal performance. The garter spring plays an important role in the efficiency of the oil seal. If its tension is too high, heat will be generated between the sealing lip and the shaft, and result in rapid wear of the lip. If too low, the spring will be ineffective and the sealing lip will be worn away leading to leakage of the fluid.
The shaft on which the oil seal is mounted has to be ground to a rough surface finish. The shaft also should be hardened to prevent grooves forming on the shaft when the pressure is exerted by the spring on the seal. The area where the seal is fitted also has to be ground to prevent grooves that tend to wear out the lip of the oil seal faster than normal.
When the oil seal material and the chemical are not compatible, there will be a chemical attack, which increases at high temperatures. The only way to remedy this is to select the right material for your application. If you’ll be dealing with harsh chemicals, choose oil seals that are made with reliable materials for their compatibility.
One of the main principles of power transmission is consistent lubrication. Shaft seals play a hugely important role in this. Imagine a situation involving a shaft-mount reducer – electric motor prime mover, driven by belts, motion controlled by a torque arm – with an improperly seated seal. A blown-out input shaft seal is a nightmare situation, necessitating an entire breakdown and reassembly, not to mention re-aligning and re-tensioning the belts.
For more severe oil-seal service at temperatures of 160°C (320°F) or higher for extended periods, more resistant fluoroelastomer compositions are required for long service life. High-fluorine VDF/PMVE/TFE elastomers, along with TFE/olefin FEPM elastomers, are much less susceptible to attack by oil additives. TFE/P fluoroelastomers have the requisite chemical resistance, but have low fluorine content, leading to relatively high swell and to soft vulcanizates with lower wear resistance than desired.
-

In addition to withstanding high pressures, oil seals must also be able to withstand the harsh conditions often found in industrial settings. This includes exposure to oil, chemicals, heat, and vibration, which can all contribute to the degradation of the seal over time. Proper selection of materials and regular maintenance are essential for ensuring the longevity and reliability of high-pressure oil seals.
Oil seals are made out of nitrile synthetic rubber with steel stiffener rings. Other rubbers such as viton, silicon, neoprene or poly acrylic can be used for specific applications. The stiffener rings may be stainless steel or brass where highly corrosive fluids are to be sealed. Springs are generally made of spring steel to IS: 4454:Gr.ll or from stainless steel or bronze for corrosion resistance