As we all know, the engine and gearbox as the most core parts of the car, its performance is directly related to the quality of the whole car. As the engine in the heart of a car, it often leaks water, oil and gas, which is what we often call "three leaks". This kind of phenomenon will lead to the increase of fuel consumption, aggravating the wear of parts and components and the decrease of power. What's more, when the vehicle is running at high speed, the oil leaks into the parts (such as turbocharger) that are rotating at high speed and heating rapidly, it may cause the oil to self ignite, and then further ignite the whole vehicle, which is one of the reasons for the auto ignition. There will also be oil and water leaks in the transmission. The oil leakage will make the lubricating oil pressure in the gearbox insufficient, which will lead to the impact slip fault of the gearbox; the water in the gearbox will directly lead to the oxidation and deterioration of the internal oil in the gearbox, and then reduce its friction coefficient, so that the friction of the vehicle components is not enough, resulting in towering, impact, slip and other faults. These faults of engine and gearbox will pose a serious threat to people's personal and property safety, and the reason for these faults is that the sealing between engine and gearbox fails to meet the requirements.
The engine is not sealed well and there is oil leakage
Automobile plane seal refers to the formation of a barrier layer between the plane of two parts, which can well prevent the leakage of gas and liquid. When the engine is running, it will cause high temperature, high pressure and many kinds of oil, gas and antifreeze in the engine. The system is complex, the sealing is difficult, and the sealing material and technology demand is higher. Therefore, the sealing performance of engine can be used as an important reference index to evaluate the quality of automobile.
At present, there are two commonly used methods of plane sealing, one is to use sealing gasket, that is, to use the sealing gasket made of cork, asbestos, fiber or metal, etc., to place it between the two planes to play a role in filling the gap. Such as: oil resistant asbestos rubber pad, asbestos free fiber latex pad, asbestos free oil resistant rubber pad, rubber cork pad, rubber sealing ring, etc. Due to the simple assembly, high strength and good compressibility, the market demand of gasket is large. The disadvantage is that the gasket will be used with time, and under the repeated compression and erosion of load and contact medium, the thickness of the gasket will decrease and the elasticity will gradually lose, leading to seal failure. The second method is to use sealant to achieve sealing. The sealant is generally liquid or paste, which can achieve 100% full contact on the surface of two base materials during construction. The adhesive layer formed after full curing can play an excellent sealing effect. The commonly used plane sealants on the market mainly include solvent rubber sealant, anaerobic sealant and silicone sealant, among which silicone sealant avoids the shortcomings of easy shrinkage after curing of solvent based sealant, and the cost is much lower than that of anaerobic sealant, with good comprehensive performance. Silicone sealant does not contain volatile solvent, and can be converted into elastomer 100% after moisture curing, so as to eliminate possible infiltration Leakage path. Silicone sealant has excellent adhesion, good oil resistance and can be used for a long time in high and low temperature for most of the base materials, so it has a large application space in automobile lubrication system and cooling system. In the field of plane sealing, sealant is gradually replacing gasket, and "rubber instead of gasket" has become a new trend.