What are the use points and influencing factors of rubber sealing rings？
First, what are the use points of rubber sealing rings?
1.1 Select the appropriate sealing ring material and hydraulic oil, as well as the adaptability to the working temperature and the compatibility of the oil;
1.2 It is necessary to cooperate with the geometric position accuracy (concentricity) of the sealing ring relative to the sliding parts, good material (such as hard chrome plating) and fine surface roughness can prolong
the service life;
1.3 The sealing surface is required to be well lubricated to prevent dirt from invading people. It is also necessary to use the oil that meets the specified cleanliness level and the correct installation method;
1.4 Secondly, the oil seal used for hydraulic pump and motor journal not only requires the roughness of the sliding surface to be within Ra of 0.25m, but also requires hard chrome plating on the surface. In the specific
use, it is necessary to adjust the oil seal lip appropriately according to the specific situation. The radial spring force makes it moderately tight, and a mounting sleeve or a thin gasket should be used to protect the sealing
ring during installation, so as to prevent the lip from rolling and twisting, causing the spring to slip out;
1.5 The inner surface of the hydraulic cylinder is usually processed by rolling, which not only improves the surface roughness, but also makes the surface hardened by cold work, which is beneficial to prolong the service
life of the sealing ring. In addition, the pressure used, the length and type of the sliding surface also have a great influence on the service life.
Second, what are the influencing factors when using rubber sealing rings?
2.1 The pressure generated by the equipment at work is an important factor that determines the quality of the rubber sealing ring. The length and level of the cycle change of the working pressure have a great influence
on the damage of the rubber seal (such as extrusion). The higher the pressure, the greater the effect of other factors on the performance of the seal, such as temperature, speed, material of the seal, the gap between the
piston and the cylinder, and the gap between the piston and the cylinder head.
2.2 Working temperature and friction force, it is difficult to describe the maximum service temperature and minimum service temperature of a rubber sealing ring material, because it is the result of the combined influence
of a series of factors. For the different working temperatures of the piston and the piston rod, they should be selected differently. Another is the surface roughness of the seal product, the characteristics of the surface, the
pressure, the medium, the temperature, the material of the sealing ring, the specification and type of the sealing ring and the speed of movement, which are all factors that affect the sealing ring.
2.3 Treatment of sealing section (surface): practical experience shows that the surface characteristics of the cylinder piston and piston rod have a great influence on the life of the sealing ring. Surface properties are often
defined by the value of surface roughness RA, which is the arithmetic mean of the absolute value of the deviation of the surface shape from the centerline. However, these values do not fully represent the effect of surface
conditions on the sealing ring, because even under the same roughness, different surface shape characteristics can lead to different degrees of sealing ring wear on the sealing element.