Причины выхода из строя уплотнительного кольца
RUBBER О-образные кольца are commonly used in pumps. Because of its very simple shape, it is easy to manufacture and low in cost. No matter how big the overall size of the O-ring is, its cross-sectional size is very small (only a few
millimeters), so it is light in weight, consumes less materials, is simple in use, and is easy to install and disassemble. , The more prominent advantage is that the O-ring has a good sealing ability and a wide range of use. The
working pressure of the static seal can reach more than 100MPa, and the dynamic seal can also reach 30Mpa. The applicable temperature is -60 ~ 200 ℃, which can meet the requirements of various media. Therefore, it is
more and more widely used in the design of pumps.
The O-ring is installed between the groove and the sealed surface with a certain amount of compression, and the resulting rebound force gives the sealed smooth surface and the bottom surface of the groove an initial
compressive stress. So as to play a sealing role. When the pressure of the sealed liquid increases, the deformation of the O-ring also increases, so that the pressure transmitted to the sealing surface also increases, and the
sealing effect also increases. This is why O-rings have good sealing ability.
Although the O-ring seal is reliable, if you do not pay attention to the conditions of use, leakage will occur, usually in the following situations:
1. The size of the groove where the O-ring is installed is out of tolerance, especially when the depth is too large, the compression deformation of the O-ring after installation is insufficient and the sealing ability is affected.
Generally, the compression deformation of the O-ring should be between 18% and 22% after installation.
2. The nominal size of the Уплотнительное кольцо is too different from the actual installation size, and the O-ring is formed to work under the condition that the cross-sectional size is reduced after stretching, resulting in insufficient
compression deformation and leakage.
3. When the O-ring is installed, the O-ring is scratched and leaks due to the lack of smooth chamfering or rounding at the inlet of the sealing surface.
4. The material of the O-ring seal is not suitable for the sealing medium and will fail after being eroded.
5. The O-ring will be aged and deteriorated after being used for too long, and the elasticity will be reduced and then it will fail. Therefore, the O-ring is generally replaced when the equipment is overhauled.
In addition, the hardness of the O-ring, the roughness of the groove and the sealing surface also affect the sealing effect of the O-ring.