The waterproof ring of the cylinder liner is a rubber O-ring with a circular cross-section. Compared with a skeleton oil seal, it has a simple structure without a skeleton and no self-tightening spring. The 8699970272 o ring is a common type of sealing ring. The 8699970272 o ring is sealed by the flexibility and elasticity of rubber itself. If installed improperly, a large amount of cooling water in the water jacket will seep into the crankcase, causing deterioration of the engine oil, deterioration of lubrication quality, aggravating the wear of all moving parts of the engine, and even causing major failures such as bush burning and axle holding.
Pay attention to the following items when installing 8699970272 o ring:
(1) If the 8699970272 o ring is too thin or the water seal groove of the cylinder liner is too deep, the 8699970272 o ring cannot be higher than the arc surface after being installed in the water seal groove of the cylinder liner. Wrap a layer of asbestos rope, apply water-resistant calcium-based grease, and then put the 8699970272 o ring into the water seal groove, and then press the cylinder liner into the body seat hole.
(2) If the 8699970272 o ring is too thick or the water seal groove of the cylinder liner is too shallow, and the arc surface is too high after being installed, it will not only be difficult to install the cylinder liner, but also damage the rubber water seal or even squeeze the cylinder liner. The rubber water seal can be evenly polished with emery cloth until it protrudes to a suitable height after being installed in the water seal groove. Then apply grease to the surface of the 8699970272 o ring, and the cylinder liner can be pressed into the body seat hole.
(3) If the depth of the water seal groove is different, and the rubber O-ring seal is uneven after being installed on the cylinder liner, you should carefully check whether the problem is the rubber O-ring seal or the water seal groove. Replace the problematic part.
(4) Before the rubber O-ring seal is inserted into the water seal groove of the cylinder liner, the rubber O-ring seal and the water seal groove should be cleaned, and impurities and dirt should be avoided during installation. After installing the rubber O-ring seal on the cylinder liner, carefully check whether it is twisted or not grooved. Before installing the cylinder liner, the dirt on the cylinder body should be carefully removed, and a layer of oil should be applied to the surface of the lower bearing hole, and then the cylinder liner should be slowly pressed into the bearing hole.
In daily work, if you do not pay attention to the use of 8699970272 o ring, the O-ring will lose its sealing performance.
The various materials used to make the 8699970272 o ring will produce compression stress relaxation under compression. At this time, the compression stress decreases with time. The longer the use time, the greater the compression rate and the greater the amount of stretch, the greater the drop in stress caused by the rubber stress relaxation, so that the 8699970272 o ring has insufficient elasticity and loses its sealing ability.
Note: It is advisable to try to reduce the compression rate under permitted usage conditions. Increasing the cross-sectional size of the O-ring is the easiest way to reduce the compression rate, but this will increase the size of the structure.
It should be noted that when calculating the compression ratio, people often ignore the reduction in section height caused by the tension of the 8699970272 o ring during assembly. 8699970272 The change in cross-sectional area of the o ring is inversely proportional to the change in its circumference. At the same time, due to the effect of pulling force, the cross-sectional shape of the 8699970272 o ring will also change, which is reflected in the reduction of its height. In addition, under the action of surface tension, the outer surface of the 8699970272 o ring becomes flatter, that is, the section height is slightly reduced. This is also a manifestation of O-ring compression stress relaxation.
The above is an introduction to the use of 8699970272 o ring. If you have more questions, please contact Guangzhou Hui Yuan Mechanical & Electrical Co., Ltd.!