Polyurethane seals from Shandong XinRuiTuo Precision Industry Co., Ltd. is popular used all around the world. Today, I will lead you to learn the factors that affect the sealing performance of seals.
Movement speed, working temperature, working pressure, working medium, side load and hydraulic shock may all affect the sealing performance of the seal.
1. Movement speed: If the movement speed is too high, it is easy to damage the lubricating oil film. Once the oil seal is not well lubricated and causes friction and heat, the service life will be greatly reduced. The oil seal needs to work within a certain working speed range.
2. Working temperature: Low temperature will reduce the elasticity of the oil seal, cause leakage, and even cause the entire oil seal to become brittle and hard. Excessive temperature may cause the volume of the oil seal to soften and expand, resulting in increased frictional resistance of the oil seal during movement and reduced pressure resistance of the oil seal.
3. Working pressure: The oil seal has a minimum start-up pressure requirement, low-pressure work must choose an oil seal with low friction performance and small start-up resistance. Polyurethane oil seals are not suitable for working at lower pressures; under high pressure, full consideration should be given to the deformation of the oil seal under pressure, and anti-extrusion retaining rings can be used if necessary. The working pressure range of oil seals of different materials is also different.
4. Working medium: While keeping the working medium in the equipment clean, it is also necessary to select the working medium in strict accordance with the manufacturer's recommendations. The aging of the oil may accelerate the aging and wear of the oil seal, and even impurities may scratch or embed the oil seal and cause the seal to fail. So we need to check the oil quality regularly, and check and replace the oil filter or oil.
5. Side load: Usually, in order to make the oil cylinder bear a larger load, a support ring is required on the piston. The role of the seal and the support ring is different, and the seal cannot replace the support ring as a load. For hydraulic cylinders with lateral force, in order to avoid leakage caused by the oil seal working under eccentric conditions, it is necessary to add a supporting ring with a strong bearing capacity (a metal ring can be used for heavy loads).
6. Hydraulic shock: For example, when the excavator bucket suddenly hits a stone or the crane lifts or puts down a heavy object, a corresponding hydraulic shock will be generated. The high pressure generated instantaneously by the hydraulic shock can tear the oil seal or partially squeeze it into the gap in a very short time, causing serious damage.
