CAT SEALS®

Duo-ConeTM Seals Installation

Cat Duo-Cone Seal AssemblyContents:• (2) Metal Seal Rings• (2) Elastomeric Toric Rings

Remove any foreign material from the rubber torics(2), the ramps (7) and the lips (8) of both seal rings.
This should also be done with a lint-free wipe and a nonpetroleum based solvent. Dry with a clean wipe.

Terminology
Place the rubber torics on the metal seal ring at the bottomof the seal ring ramp and against the retaining lip.

1. Seal Ring 		
2. Rubber Toric
6. Seal Ring Face
3. Housing Retainer Lip
7. Seal Ring Ramp
4. Housing Ramp
8. Seal Ring Retaining Lip
5. Seal Ring Housing
9. Installation Tool

Handling the Seals

The idea is to protect the seal face. The more precausions
taken, the more likely the seals will last in the field.

Housing Preparation

The housing components that contact the rubber
toric rings (3 and 4) must be free from foreign material (oil,grease, dirt, metal chips, dust or lint particles, etc.) before
installing the seal. The housing should be cleaned using alint-free wipe and a non-petroleum based solvent. Dry witha clean wipe.

Make sure the rubber toric is straight on the seal ring andnot twisted. Be careful not to nick or cut the torics during
the assembly, as this can cause leaks.
Put the installation tool onto the metal seal ring and rubber
toric. Lightly dampen the lower half of the rubber toric withthe appropriate assembly lubricant.
Techniques to dampen the toric include wiping with a lintfree towel, lubricating using a clean foam brush, or dippingin a container lined with towels saturated in the assembly
lubricant (as shown).

Seal groups with silicone torics can be assembled using
a freezer to slightly contract the toric rings. Seal groups
should be placed in a freezer for 5 minutes at -40oC to -18oC
prior to installation. Contraction will be sufficient to allow
installation. Groups should warm to room temperature prior
to further assembly.

The rubber toric can twist if it is not wet all around during
installation or if there are burrs or fins on the retaining lip of
the housing. Twists, misalignment, and bulges of the toric(as shown) will result in seal failure. If correct installation isnot obvious, remove the seal from the housing and repeatprocess.

Approved Assembly Lubricants

The rubber torics must never slip on the ramps of either
the seal ring or the housing. To prevent slippage, allow
adequate evaporation time for the lubricant before
proceeding with further assembly.
Once correctly in place, the rubber toric must roll on theramp only. The following shows incorrect installations
resulting in cocked seals.

• Isopropyl Alcohol*• Houghto-Grind 60 CT• Quaker® Solvo Clean 68-RAH(*) All applicable safety and disposal guidelines for flammable liquids must befollowed.
Note: Do not use Stanosol or any other liquid that leaves an oil film and/or does
not evaporate quickly.

Installation Process

With the lower half of the rubber toric still wet, use theinstallation tool to position the seal ring and the rubber toricsquarely against the application housing (as shown).
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2

3

For smaller diameter seals, use sudden and even pressure
to push the rubber toric under the retaining lip of thehousing. For larger diameter seals, which will not press inwith sudden and even pressure, it is acceptable to work thetoric past the retaining lip by starting one side and tapping
the opposite side of the installation tool with a rubber mallet
until it is engaged past the retaining lip of the housing.

Wipe the face of each seal ring using a lint-free wipe.
No particles of any kind are permissible on the sealing
surfaces. (Even a hair can hold the seal faces apart andcause a leak)

Check the assembled height variation (A) in a least four
places, 90o apart, use a caliper, toolmakers’ ruler or any
other calibrated measuring device.
A

Apply a thin film of oil on the entire seal face of one orboth seals using a lint-free applicator. Oil must not contact
surfaces other than the sealing face.
The difference in height around the ring must not be morethan 1.0 mm. If small adjustments are necessary, do notpush or pull directly on the seal ring. Use the installation
tool to push down and your fingers to pull up uniformly on
the rubber toric and seal ring.

Final Assembly

While completing the final assembly of the unit, makesure that both housings are in correct alignment and areconcentric. Slowly bring the two housings together. Highimpact can scratch or break the seal components.

1

5If the rubber toric slips at any location, it will twist, causing
the seal rings to cock. Any wobbling motion of the seal isan indication of cocked seals and can cause dirt to enter by
pumping mud past the torics.
The following examples show the effects of a cocked sealgroup.

ABX

Y

The above depicts how the torics have slipped instead ofrolling on the left hand side of the seal. The following shows
the same seal after the bottom half is rotated 180o.

ABYXFor more information on Cat Seals
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