News

Wiper Seal

Update:2016-01-21

Oil Seals can be used as a dust seals, but for the serious dusty condition or in order to protect 

other seals, general use a special Wiper Seal. DSH Seals will introduce Wiper seal to you.

The Seals for hydraulic machinery are made of rubber, for pneumatic machine are felt (square 

or trapezoid),  aircraft and frigid zone choose metal to manage piston rod avoid external icing, 

chemical industry department also choose metal in order to prevent adhesive material on the 

piston rod. Square or trapezoidal Wiper Seal in the sealing mechanism belongs to packing 

Seals, dust prevention ability is associated with the closer degree of contact, the tighter dust-proof 

capability, the greater friction resistance.

There is not so much difference between wedge shaped Wiper seal and lip ring, which relies on 

the tip of the lip contact force scrape off dust and dirt, its scraper dust and dirt function based 

on the contact force of lip tip. The friction resistance is small, but the angle between the lip tip 

and shaft surface has a great influence on the sealing and wear resistance to its dust efficiency. 

When lip tip outward, which angle is greater than 4° results will be OK, when the lip tip inward, 

dust-proof effect will be bad.

The lip and shaft contact state also directly impact on dust-proof effect and wear on the lips. Several 

common normal contact state, thin oil film, good dust-proof effect, less wear, the amount of 

interference is too big, that contact too tight, wide contact surface, if change the contact angle, so 

that the lip tip tilt, not only dust-proof effect is bad and large friction resistance, tip lip contact is not 

sufficient, friction is small, but scraper function is not good. The lip tip contact angle is too large, 

dust prevention effect is short, it easy to wear and cause by serious oil spill. 

The wiper seal is extremely important for the protection of the critical parts of the hydraulic 

equipment. Penetrate the dust, not only wear the seals, but also greatly wear guide sleeve and 

the piston rod, that impurities go into the hydraulic medium, also affect the function of operation 

of valves and pumps. In the worst case, it may be damaged the device.

Wiper seal can get rid of any dust on the surface of the piston rod, but without damaging the oil 

film on piston rod, it's good for seals lubrication.

DSH Seals could offer various wiper seal, welcome to contact us for more details.