The invention of hydraulic systems has permitted industry to lift, push, pull and maneuver heavier objects than previously thought possible. From steering the largest ships to stopping the family car, the applications of hydraulics has changed history in many ways.
Any hydraulic system is only as good as the seals utilized. Seals can be
subjected to intense pressures and high temperatures. Dynamic seals may be
subjected to continuous motion. In many cases, the seal is also exposed to
corrosive materials, including chemicals and metal contaminants. It is intended
to retain hydraulic pressure within the system under enormous pressure and
Therefore, it must be constructed of high quality materials and fabricated
to exacting standards. A small deviation from design specifications can lead to
premature erosion and eventually failure of the component.
Seal failure will cause a leak in hydraulic fluid and a corresponding loss
in hydraulic pressure. Whether it is the failure of a dynamic or static seal, a
broken seal often leads to failure of the hydraulic system.
For this reason, frequent inspection of all seals in a hydraulic system is a
good business practice. When warranted, a defective or potentially defective
seal should be replaced. Quality seal materials are made from a variety of
materials, depending on the hydraulic system and the stress factors to which it
will be subjected.
Nitrile is often used when a high temperature variation is to be expected
and when the seal will be in contact with vehicle fuels. Ethylene propelyene
rubber (EPM) is used in applications needing a flexible but strong compression
and chemical resistance to acids, alkali and salt. Fluorocarbon rubber can
normally withstand the highest temperature variations of all materials.
Fabrication of retrofit hydraulic
shaft seals is a process of more than a dozen manufacturing steps,
from initial measurement of the old shaft seal, to matching and verifying the
material to be used, to cutting and re-measuring the part. For businesses
needing a new seal for a hydraulic system or those seeking an upgrade on
existing components, there are companies that can fabricate a quality
replacement to original specifications.