Correctly understand the oil leakage phenomenon of shock absorber
In order to meet the application requirements of the function of the shock absorber itself, there is a thin oil film on the surface of the piston rod in the design of the shock absorber itself. These oil films will be scraped off by the dust lip on the oil seal of the shock absorber when the shock absorber is tightened. At the same time, a very small amount of oil will accumulate on the upper part of the oil seal. Due to the high permeability of this oil, the oil accumulated on the upper part of the oil seal will start to diffuse from the upper part of the shock absorber to the lower part, forming a thin oil film, which makes people mistake this situation as oil leakage, In practice, this situation does not affect the application.
Oil film: the key factor affecting the durability and smoothness of oil seal, the composition and scraping of oil film
When the piston rod extends, it forms an oil film. When the piston rod is pressed in, the oil film will remain outside the oil seal when it is scraped by the oil seal dust lip. In order to enable the dealer service providers to correctly understand the principle that the shock absorber will naturally form an oil film during normal operation, they can give the user a correct explanation. The oil leakage mechanism of shock absorber is discussed as follows:
Shock absorber oil leakage: because there are microcracks on the surface of the piston rod coating, the microcracks on the piston rod store a certain amount of damping oil to form an oil film, making the friction between the piston rod and the oil seal wet friction, thus improving the performance of the pneumatic ball valve, and greatly extending the service life of the pneumatic ball valve. A small amount of oil leakage is a normal phenomenon. The composition of the oil film is a special design to ensure the function of the shock absorber and extend its service life.
The oil stain of ordinary oil leakage does not exceed the ball valve disc. The oil stain is limited to the place from the oil seal of the pneumatic ball valve to the lower ball valve disc. It is normal oil leakage and cannot be considered as oil leakage. The design of oil filling volume in the ordinary shock absorber once considered the loss of oil leakage. When the shock absorber was consumed, the oil volume was filled according to the specification. When the normal loss of oil in the use process does not exceed 25ml, the shock absorber will not appear abnormal. The results of the bench durability test on the oil leaking shock absorber show that oil leakage will not constitute oil leakage even after driving 200000 km, After the experiment, the amount of synthetic oil is reduced by 5-20ml. The performance of the shock absorber meets the application requirements. Acoustic wave characteristics and noise reduction methods
A acoustic system is composed of three rings of sound source, transmission path and receiver. Therefore, noise control must be considered from these three aspects, not only to study it separately, but also to consider it comprehensively as a system.
B Suppress noise at the sound source, which is the most basic measure, that is, active disposal. It includes reducing the excitation force, reducing the response of each link of the system to the excitation force, and modifying the operation procedure or technological process.
C In the control of sound transmission, acoustic control is adopted, that is, passive disposal. This is a common technology in noise control, including sound insulation, sound absorption, noise elimination, damping and vibration reduction measures.