Gardner Denver GAF P Series, Руководство по эксплуатации и обслуживанию

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SB-7-622 Page 28
11. Impeller should now be checked for free axial movement by hitting the ends of the impeller shafts with the
palm of your hand.
12. Push the impellers against the gear headplate and recheck the total end clearance between the drive
headplate and the impellers (see FIGURE 7-4, page 31).
A. If total end clearance is insufficient, loosen impeller case to headplate bolts on either headplate, and
move the headplate away from the case far enough to insert a paper shim in the amount equal to the
insufficient clearance. Retighten case bolts and again check the total end clearance. Refer to FIGURE 7-4,
page 31, for correct clearance.
B. Excessive end clearances normally will require new impeller assemblies, but in some circumstances the
impeller case can be removed and reduced in width by machining off the amount of excess clearance.
These impeller-to-impeller and impeller-to-case clearances are extremely critical. Even thought the
blower may turn freely by hand when cold, under operating conditions, the parts expand, and the
rotors are subject to slight deflection.
If the clearances are not sufficient the impellers may contact each other or the housing with
destructive results. If the clearances are too great, the blower may not develop the pressure or
airflow that is required to perform its function.
FIGURE 7- 5
13. Impeller tip to case clearance should be checked at this time by inserting the correct thickness feeler gauge
between the tip and the case (B) and rotating the impeller (see Figure 7-4, page 31). Repeat the procedure on
both impellers.
NOTICE
When checking the tip to case clearance, move the feeler gauge over the entire length of the
impeller to ensure that the tips do not bind along their length.
14. Replace the drive shaft grease seal (31) in the drive end cover (29). The seal lip should always face toward
the bearing or lubricant. Pack the bearing cavities with the recommended grease.
15. Secure drive cover (29) and wavy spring (28) to drive headplate using capscrews (30). Refer to Figure 7-8,
page 36, for torque specifications.
NOTICE
Exercise care not to damage the seal lip as it passes over shaft keyway.