Exclusion seals, wipers, and scrapers clean the surface of a retracting rod, removing abrasive particles such as dirt, mud, and ice. This protects the seal and extends service life. The importance of wipers cannot be overemphasized. Often a seal fails prematurely because the wiper wears out long before the primary seal. In such cases failure is not due to misapplication of the seal, but to the wiper not protecting the seal from abrasive wear. are usually produced from a material like high-quality polyurethane. They are designed to snap directly into the glands on common cylinders. Typical properties for wiper materials are: hardness, 85-95 Shore A; tensile strength, 6,000 psi; elongation, 400%. They can typically be used in a temperature range from -40 to 210°F, although some manufacturers predict reduced life if the rods are exposed to steam and water over 190°F. are made with a sealing lip at the bottom and a rod wiper at the top, so the wiper can perform as a pressure-energized lip seal inside the cylinder at the same time it wipes contaminants from the outside. The two most common types are a double-lip U-seal and a double-lip V-seal. Both are one-piece snap-in replacement seals that provide both sealing and wiping action. are exclusion seals that have a metallic lip or hard plastic scraping element to scrape heavy or tenacious materials from reciprocating shafts. The hard lip is kept sharpened by the honing action of the shaft. Wipers are sometimes used behind scrapers to catch any fine particles or fluids that pass the scraper. There are two types of scrapers, conical scrapers and scraper rings. The conical scraper has a sharp knife edge that digs under the foreign matter and lifts it from the shaft. The scraper ring has a flat top, 1/32 to 1/16 in. wide.
Products & Services
Exclusion seals are comprised of wipers, scrapers and V-ring seals.
Dynamic seals include oil seals, hydraulic and pneumatic seals, exclusion seals, labyrinth seals, bearing isolators, and piston rings. They create a barrier between moving and stationary surfaces in applications such as rotating shafts and pistons rings. This is a general search form; more detailed search forms are available.
Bearing isolators are dynamic seals designed to protect bearings from outside contaminants. They are comprised of a rotor (rotating) and stator (stationary) member.
Oil Seals and Grease Seals
Oil seals and grease seals have a flexible lip that rubs against a shaft or housing to prevent the leakage or ingress of fluids and dirt.
V-Rings are all-rubber seals that seat directly on the shaft and seal axially against a counterface, housing, seal case or similar surface.
Topics of Interest
Exclusion seals, wipers, and scrapers clean the surface of a retracting rod, removing abrasive particles such as dirt, mud, and ice. This protects the seal and extends service life. The importance of...
3.2 Lip Seals
The lip seals currently used for sealing rotary shafts have evolved from the lip seals made from leather used during the 1930s. The development was largely empirical for some 50 years...
Unlike lip seals and squeeze packings, felt seals require relative little shaft pressure to function effectively. They are commonly used near ball and roller bearings as lubricant retainers.
Apart from the elastomeric lip material and interface between the sealing lip and application shaft, a critical design feature of the seal lip is its geometry. Lip geometry is one of several factors...
In most lip seals, increasing fluid pressure increases lip-contact pressure. In a properly designed and installed seal, the lip rides on a thin film of lubricant. Because the film does the sealing,...