Contamination by dirt or the intrusion of dirt into cylinders is the most common cause of failure in mobile machines. As operating cycles and working conditions of the machines and equipment continue to rise, high availability is of crucial importance to all end users. The AV wiper by Parker Prädifa provides effective protection against system contamination and corrosion and thus contributes to the high availability of mobile machinery.
The wiper is the major element on the hydraulic cylinder to prevent the intrusion of dirt. It protects the entire hydraulic system against, dust, dirt, moisture and other environmental influences. Due to increasingly sensitive elements being used within hydraulic circuits the wiping function has been steadily gaining importance as contaminated fluid systems are common causes of total failures with high consequential costs.
To improve the wiping function Parker-Prädifa has developed a special wiper profile with the following features:
- Dirt shield
- Dirt sealing edge on the groove side
- Double wiper
- Pressure relief drill hole
- Optimised wiper lip geometry
- Time-tested sealing function due to robust seal profile
Range of application
The AV wiper can be used in all hydraulic cylinders and is particularly well-suited for mobile applications. The molded dirt shield on the wiper prevents the migration of moisture underneath the wiper in the groove. The common occurrence of corrosion in the groove can thus be avoided. In applications with a vertically positioned piston rod head (piston rod head pointing upwards) the dirt shield to protect the seal groove is particularly effective. Water running down the piston rod is diverted and does not enter the wiper groove. Due to the press fit in the housing and the pressure relief drill hole, the risk of the wiper being pushed out of the cylinder housing is minimized.
-35 to +100 °C
≤ 2 m/s
Article contributed by Dr.-Ing. Peter Kreißl, market unit manager hydraulics, Parker-Prädifa, Packing Division Europe