Ross CDA-10 Installation, Maintenance And Operating Manual Download Page 12

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MAINTENANCE

A. AGITATOR SHAFT SEALS, VACUUM RATED MIXERS.

1. Dry Running Flexi-Lip Seals.

The Agitator Shafts, as standard, are sealed with a Dry Running Double Flexi-Lip Seal made from FDA
MF-Teflon with an o-ring installed on the seal OD. This seal is installed from below the Vacuum Cover and
requires no adjustment. Keep the area around the seal clean and free of dirt/debris to protect the seal and
provide a long life for the seal.

To replace the Agitator Shaft FlexiLip Seal, remove the Blades and Seal Retainer Plates (if any), clean the
shaft ** and pull the FlexiLip Seal from its housing. Clean the area where the seal contacts the shaft (See
**IMPORTANT NOTE** below) and the ID of the seal housing. Please use caution to not damage the shaft
surface since the shaft is polished to a 240-grit finish to provide the Lip of the seal with the “required”
smooth, 240-grit surface surface finish for the seal lip face to run on. A rough, scratched or damaged surface
will damage or destroy the seal (causing the seal to produce black “flakes”) and reduce the seals ability to
create/hold a proper seal.

**IMPORTANT**

When new, the FlexiLip Seal will “deposit/transfer” a thin layer of Teflon to the stainless
steel shaft surface. This will appear as a “witness” mark in the area where the lip directly
contacts the shaft. When replacing seals, it is important to remove this material and return
the shaft surface to its original 240-grit finish. This is done by using 240-grit sand paper
and then finish using a White Scotch-Brite Hand Pad 7445. The shaft surface should
appear as new with all scratches, damage and the Teflon “witness mark” layer completely
removed.

To install the new seal, using a thin piece of plastic shim stock, wrap the bottom of the Shaft with the plastic
shim stock to form a cone. Fit the new FlexiLip Seal over the cone and work it over the shaft OD. Move the
seal and the shim stock together up the shaft until the seal reaches its location. Slide the seal off the shim
stock and press the seal into the bore/housing. Please note that if there is no external seal retainer plate that
bolts to the Housing or Gearbox, the seal bore hole will have a .010” lip on its ID which the seal must be
pushed past. This lip helps maintain the seal location in the bore hole. DO NOT LUBRICATE THE SEAL.
Only the o-ring located on the OD of the FlexiLip Seal can be lubricated, if required.

** Please note*** When new, FlexiLip Seals can produce a minor amount of “flakes” during their “wear-
in” period. The wear-in time period depends on the shaft diameter, seal size and shaft speed. Typically the
time frame is less than 10-minutes at full speed. The flaking material should be removed by gently wiping
the area. Do not disturb the seal. If flaking persists, either the seal lip face(s) is damaged, the shaft surface is
damage or the seal lip faces have dirt, debris or lubrication on them. Repeat the above procedure with new
seals.

For additional questions or further guidance, please contact Ross directly.