Broad selection of seal and load ring materials

Seal Ring Materials

Caterpillar offers the widest choice of seal ring material options in the industry. The materials have been engineered to excel in the many different applications in which Cat seals are integrated.

For further information on any seal ring material please consult Caterpillar .

Shown below is a general comparison between seal ring materials available.

C6
C6 was developed for applications that require high speed and superior corrosion resistance. This alloy offers greater speed capabilities over Stellite with higher resistance to scoring, wear, and corrosion. The C6 alloy is available only from Caterpillar. It is the material of choice around the world in large diameter wheel applications.

Stellite
Stellite has been designed for the harshest operating environments where abrasive and corrosive elements are present. Stellite’s formulation is iron based with a high alloy content designed to provide better corrosion resistance. Stellite cast seals are typically found in applications frequently exposed to abrasive and corrosive conditions with moderate rotational speeds. Typical applications include crawler tractor final drives and various undercarriage applications.

NiHard
NiHard is another iron based casting alloy offered by Caterpillar. Pressure velocity characteristics are slightly greater than Stellite, but wear life and corrosion resistance have shown to be less, in tests conducted by Caterpillar. Typical applications would include undercarriage and final drive applications where corrosion resistance is not essential, but seal surface speeds prohibit the use of Stellite.

Formed (Duo-Cone™ Only)
Formed seals were developed for applications that do not require the high levels of corrosion and abrasion resistance, but the versatility of a face seal is desired. Formed seals are used extensively in axle, winch, and final drive applications. Formed seals are interchangeable with cast seal retainers, provide similar load and speed capability as the Stellite seals, at a significantly lower cost.

Forged
Forged seals are available on a limited basis from Caterpillar. These seals have been used successfully on undercarriage applications where minor wear is present and seal cost is critical.

Load ring materials.

Several load ring materials are available to meet a variety of application requirements. The most common materials are Nitrile and silicone, while fluoroelastomer (FKM) and Hydrogenated Nitrile (HNBR) are available for more specialized applications. The table below provides a brief comparison between Cat seals load ring options.

Nitrile (NBR)
Nitrile is compatible with most mineral-based lubricant oils. Nitrile load rings offer the maximum resistance to abrasion. It is the most common load ring material choice and is used in most standard axle, final drive, and undercarriage applications.

Low Temperature Nitrile (LT-NBR)
Low-temperature Nitrile was specifically developed for highly abrasive, low-temperature applications. Typical applications include undercarriage idlers, rollers and final drives.

Silicone 
Silicone uses are extreme high (wet disc brake systems) or extreme low (arctic environment) temperature applications.

Hydrogenated Nitrile (HNBR)
Hydrogenated Nitrile is a Nitrile-based material and has very similar abrasion resistance characteristics to standard Nitrile, but Hydrogenated Nitrile has better temperature resistance to permanent deformation.

Flourocarbon (FKM)
Fluoroelastomer is a fluoroelastomer and is typically used where extremely high temperatures are a concern and low temperatures are never a problem.

For more information about Cat seals, email catseals@cat.com