Mounting Tapered Bore Spherical Roller Bearings on Adapter Sleeves
Step #1 Check Shaft Tolerance
Step #2 Inner Triple Seal
Step #3 Adapter Sleeve – Clean Bore & Outside Diameter
Position adapter sleeve on shaft, threads outboard as indicated, to approximate location with respect to required bearing centerline. Micronized or powdered (not flaked) graphite or light oil applied to the sleeve outside diameter surface, results in easier bearing mounting and removal.
Measure the unmounted radial internal clearance in the bearing by inserting progressively larger feeler blades the full length of the roller between the most vertical unloaded roller and the outer ring sphere. (See Chart Below) Do not roll the feeler blade through the clearance: slide it through. Record the measurement of the largest size blade that will slide through. This is t he unmounted radial internal clearance.
Unmounted Radial Internal Clearance of Tapered Bore
Spherical Roller Bearings (In Inches)
Step #5 Bearing – Clean Bearing Bore
Mount bearing on adapter sleeve, starting with the large bore of the inner ring to match the taper of the adapter. With the bearing hand tight on the adapter, locate bearing to the proper axial position on the shaft. (Do not apply lockwasher at this time because drive up
Step #6 Locknut
Apply the locknut with the chamfered face toward the bearing. Use a lubricant on the threads and face of the locknut where it contacts the inner ring face of the bearing to make easier mounting for larger sizes. Larger size bearings will require a heavy duty spanner wrench and sledge hammer to obtain the required reduction in radial internal clearance. Do not attempt to tighten the locknut with hammer and drift. The locknut will be damaged and chips can enter the bearing. In larger bearing sizes it will be impossible to tighten the locknut far enough with a drift. If lower half of housing is in position, support the shaft such that the bearing outer ring is free to rotate. This will prevent internal damage to the bearing during tightening of the locknut.
Remeasure internal radial clearance at this time. Tighten locknut and measure radial internal clearance with feeler blades between the most vertical unloaded roller and the outer ring sphere or at the 6:00
position if the bearing is hanging free on the shaft, until the radial internal clearance is less than the measurement in Step 4 by the amount shown in the following chart. (Next Page)
Recommended Clearance Reduction for Tapered Bore Bearings (In Inches)
Remove locknut and mount lockwasher on adapter sleeve with inner prong of lockwasher toward the face of the bearing and located in the slot of the adapter sleeve. Reapply locknut until tight. (Do not drive bearing further up the taper as this will reduce the radial internal clearance previously secured. Check to make certain clearance has not changed.) Find lockwasher tang that is nearest a locknut slot. Bend one of the lockwasher tangs in a slot in the nut. If slot is slightly past tang, don’t loosen nut, but tighten to meet a washer tang.
Step #8 Outer Triple Seal
Slide outer triple seal onto the shaft. Locate both inner and outer triple seals to match labyrinths in the housing.
Step #9 Lower Half of Housing
Remove any paint and burrs from the mating surfaces at the split and thoroughly clean the housing. The vertical hole at the bottom of each enclosure groove must be free of foreign matter. Set lower halves of housings on base and oil the bearing seats. Place shaft with bearings into lower halves of housings, carefully guiding triple seals into the seal grooves and being certain that the bearing outer rings sit squarely in the pillow block bearing seats. Bolt the held housing securely in place. (The free bearing housing(s) will be located and bolted after completing Step #10 and centering the free bearing(s) in the free pillow block bearing seat(s).)
A stabilizing ring should be used only if the bearing is to be held. Move shaft axially so that the stabilizing ring can be inserted between the “held” bearing outer ring and housing shoulder on the locknut side of bearing, where practical. Center all other bearings on one shaft in their housing seats.
Note: There must be only one “held” bearing per shaft. Other bearing or bearings must be “free” to permit shaft expansion. If the pillow block is to have one closed end, an end plug is supplied which fits snugly into the triple seal housing groove in place of the triple seal. It is inserted in the lower half of the housing before the upper half is bolted to the base. If grease is used as a lubricant it should be applied before the upper half is secured.
Step #11 Upper Half of Housing (CAP)
The bearing seat in the upper half of the housing (cap) should be checked for burrs, thoroughly cleaned, oiled and placed over the bearing. Especially with oil lubrication, use of a sealing compound must be applied sparingly: wipe a thin film near the outer edges. Excessive amounts are forced not only out but also in between the housing bore and bearing O.D. and this can pinch an outer ring or make a free bearing actually held. The two dowel pins will align the upper half of the housing.
Note: Caps and bases of pillow blocks are not interchangeable. Each cap and base must be assembled with its mating part.
Lockwashers and cap bolts are then applied and properly torqued to complete assembly. If shimming is required, only shims which cover the full mounting surface of the pillow block are recommended.
Here a section of the housing has been removed to show the relative position ofall the parts.