Emerson VSSG, VSG Compressor Shaft Bearing Float Inspections, 11. Bearing Axial Float Inspection

Section 5 • Maintenance/Service

Compressor Shaft Bearing Float Inspections

If float measurements are out of tolerance, contact Vilter Customer Service for further assistance.

BEARING AXIAL FLOAT INSPECTION

CAUTION

When taking the measurements, do not exceed 300 lbs of force at point of contact or damage may result to the bearings.

DETERMINE MAXIMUM APPLIED FORCE

motor and use the lever arm to push the input shaft towards the compressor. Record measurement

5.Add both measurements. If measurement is out of allowable tolerance shown in Table 5-7, the bearing may need to be replaced. Contact Vilter Customer Service.

BEARING RADIAL FLOAT INSPECTION

6.Install dial indicator to the compressor frame and zero indicator, see Figure 5-12.

NOTE

Do not exceed maximum applied force. For maximum applied forces of all compressor models, see Table 5-7.

To determine maximum applied force, take maximum applied force at hub/shaft multiplied by length of A and divide by length B. This is the maximum force that should be applied on the lever.

(Applied Force x A)/B = Applied Force (Maximum)

So, using a 36” (or 1 m) lever with pivot space of 6” (or 15 cm) would make the maximum applied force to be 60 lbf (or 235 N). Calculation is as follows:

(300 lbf x 6”)/30” = 60 lbf (Max. Applied Force)

(1335 N x 15 cm)/85 cm = 235 N (Max. Applied Force)

Force at

Hub/Shaft

Applied

Force

	Lever
	Wooden Block
Pivot Point	or Fulcrum

As a quick reference, Table 5-7 shows maximum applied forces for 36” lever with 6” pivot for all compressor models.

MEASURE

To inspect bearing axial float, proceed with the following steps:

1.Remove center member, see appropriate Drive Coupling Replacement procedure.

2.Install dial indicator to the compressor frame and zero indicator, see Figure 5-11.

3.Place lever arm and fulcrum behind compressor coupling half and push the coupling towards the motor. Record measurement.

4.Re-zero indicator, now position the fulcrum on the

7.Place lever arm and fulcrum underneath hub and push hub upwards. Record measurement.

8.If measurement is out of allowable tolerance shown in Table 5-7, the bearing may need to be replaced. Contact Vilter Customer Service.

Top View

Shaft being pushed by use of lever.

Direction of shaft movement.

Rigidly attach dial indicator.

Position on axis of compressor.

Applied Force Small wooden block or fulcrum.

Top View

Shaft being pushed by use of lever.

Rigidly attach dial indicator.

Position on axis of compressor.

Direction of

shaft movement.

Wooden block

or fulcrum

Applied Force

Figure 5-11. Bearing Axial Float Inspection

5 – 16 VSG/VSSG • Installation, Operation and Maintenance Manual •Vilter/Emerson • 35391SSG