Rubber Sealing Technology

The main part of Rubber seal is rubber,the friction coefficient  of rubber is 0.28-0.48, the thermal conductivity is poor.The friction temperature of the Rubber seal which is working is 84-95 degrees Celsius higher than that of the oil temperature. In particular the shaft at high speed, the temperature is much higher.High-temperature make the physical and mechanical properties of rubber down,and also make the rubber seal lip and the film-forming become carbide, and gathered at the lip seal surface and blocked the return of tendons, it lost its suction effect.

High temperature also make the lips film bubble,bubble movement will cause premature seal leakage and failure. Carbide can also cause lips and the shaft wear and tear.This is the main reason why rubber seal reliability is poor and relatively life is short.On the other hand, when pressing rubber seals, the mold is easily dirty, especially fluorine rubber and ACM, it will create changes of a sealed surface back ribs physical，affect the suction effect, causing leakage  and seal failure. For these reasons, the three-drain issue has been tied interference with the use of rubber sealing machinery industry.

In order to solve the leakage problem ,at home and abroad have developed a combination of PTFE wafer seals. Compared with the rubber seals, there is significant improvement from the ability of seal oil, but in structure, the surface of the lip and the shaft surface contact, friction torque higher than the rubber seal 0.72Nm, so the  consumption of the engine is much larger. Exists between the two wafers may be a leak channel, and the installation requirements are strictly, the installation position is limited, also the PTFE-containing glass is more prone to wear and tear shaft surface, the cost is also high, thus the reliability have not been well solved.
In order to overcome the above-mentioned two kinds of seals,our company have developed the wafer and thin film PTFE molded rubber seals, on the use of raw materials and the structural design,our company have got a new breakthrough.

Shown in the following areas: our company developed seals, friction torque lower than the rubber seal 0.28Nm,1Nm lower than the combination of PTFE seal wafer,so consumption is smaller. When working, the sealing lip followed well to the shaft, it can withstand 1.5mm TIR shaft eccentricity, lip materials and lubricants is not easy to form carbides, circumfluence pumping from the start to finish a good role, to gain an excellent sealing effect. The mainly reliability of sealing is the reliability of the lip. When the lip design is very reasonable, the reliability of seal decided to punch.The lip of rubber Molded PTFE film seal is the PTFE film, in the production process non-stick punch, circumfluence from start to finish to maintain the original design requirements with unmatched sealing reliability. The results show: The average life expectancy of sealed bench is 300hr, car use in general life of 100,000 kilometers (economic compensation for life), the maximum life of 400,000 kilometers, are generally 3-5 times than the rubber seal, is 1.5 times than that of a combination of PTFE seal wafer ,the wear and tear on the axial plane can not be small enough to be detected. And it's adaptable, without any assembly of parts of the impact and working conditions limitations.

Type	1. Advantages & Disadvantages	Usage
	Advantages: Friction torque is small, low power consumption, good elasticity. Disadvantages: friction temperatures are high, and under the lips of oil film temperature of a fuel tank temperature of 85-95 degrees Celsius, and under the lips, easy to set carbon, foam, so that the oil seal lip back line lost their ability to produce oil seals mold products easy to stick shape changes caused by pollution, reliable poor, dirty oil used in the average life expectancy 188hr. Life is short, easy to wear lip shaft surface, not suitable for dusty environments.	Used in automobiles, tractors and other machinery and equipment
	Advantages: friction coefficient is small, and under the lips oil film temperature is low, higher than the fuel tank temperature of 30-40 degrees Celsius, and under the lips set carbon less,the rubber seal to withstand large eccentric shaft, the largest up to 1.5mm, long life, in clean oil the average life expectancy is 2060hr, in dirty oil, the average life expectancy is 1248hr, resistant to a variety of oils, the use of the temperature 200 degrees Celsius, a small abrasion on the axial plane. Disadvantages: strict processing requirements, process complexity, strict installation demanding, there is a leak between the two wafer-channel, high cost and friction torque higher than the rubber seal 0.72Nm.	mainly used in diesel engine crankshaft oil seal
	Advantages: compared to the wafer PTFE seal, the low coefficient of friction (due to the glass containing less), under the lips, oil film temperature is low, the fuel tank above the oil temperature 25-35 degrees Celsius, and under the lips, a small set of carbon and bear the greatest eccentric shaft 1.5mm , the average long life, in clean oil is 2060hr, in dirty oil is 1268hr, there is no mezzanine oil spills, wear and tear on the axis is small, seal reliability is good, simple process, low cost. Disadvantages: Strict Installation demanding ,friction torque higher than the rubber seal, lower than the PTFE seal wafer combination.	mainly used in the engine crankshaft oil seal
	Advantages: Comparing with the above three kinds of oil seals, friction torque,  smaller (less than or more seals 0.23-0.95Nm), power consumption is small, back to good elasticity, low temperature and under the lips film, only the fuel tank above the oil temperature 10-20 degrees Celsius, and bear eccentric shaft large, long life .under the lips, is not easy to set carbon, sealing reliability, wide application and dirty non-stick mold, wear a small lip on the shaft, suitable for all kinds of misfortune, the cost lower than the fluorine rubber seal , lower than the above two kinds of PTFE seals,easy to install, without any installation conditions	Application of working conditions for one-way rotary oil seals, such as the engine crankshaft front oil seal, gearbox an axis, all kinds of transportation equipment, petroleum, light industry, engineering machinery.
	Advantages: The same with molded rubber seals with PTFE membrane (one-way back).	Mainly used in both positive and negative direction of rotation axis position, used in petroleum, automobiles, trains, engineering machinery, aircraft, etc.
	Advantages: The same with molded rubber seals with PTFE membrane (one-way back).	Can withstand pressure of 1-10MPa, the rotation speed 6000r/min seals
	Advantages: The same with molded rubber seals with PTFE membrane (one-way back).	Mainly applied to the reciprocating sealing 0-15MPa