Page 7 - EASA_AR100-2015_0815 APEX_IESCO

EASA AR100-2015 Recommended Practice - Rev. August 2015 Section 2, Page 1

Section 2
Mechanical Repair

2.1 SHAFTS manufacturer’s specifications if available. Other-
Shafts should be checked for wear, cracks, scoring wise, the values in Table 2-7 are provided as a guide.
and straightness. Shaft extension dimensions should Measure the final seal dimensions.
be checked as follows. 2.3 LUBRICATION
2.1.1 Diameter Tolerances 2.3.1 Grease
• NEMA frame size machines: See Table 2-1. If bearings require grease lubrication, grease in-
• IEC frame size machines: See Table 2-2. lets should be equipped with fittings and the inlet
2.1.2 Permissible Runout passages and tubes cleaned and filled with appropri-
• NEMA frame size machines: See Table 2-3. ate grease. Lubricant should be compatible with the
• IEC frame size machines: See Table 2-4. customer’s lubricant. Open bearings should be filled
2.1.3 Keyseat (Keyway) Width with grease during assembly.
Tolerances In the absence of the machine manufacturer’s
• NEMA frame size machines: See Table 2-5. lubrication instructions, the grease reservoir should
• IEC frame size machines: See Table 2-6. be filled to approximately 1/3 capacity.
Keyseats should be true and accommodate keys 2.3.2 Oil
to a tap fit. Lubricant, including oil for test operation, should
be compatible with the customer’s lubricant. There
2.2 BEARINGS should be a means to indicate proper oil level, such
Bearings should be inspected for failure modes
such as spalling, contamination, fretting, fluting, and as an oil sight gauge. Evidence of oil leaks should
be investigated and the cause corrected.
scoring. Bearings and bearing arrangements should
be identified and documented. Insulated bearings 2.4 FRAME AND BEARING HOUSINGS
should be tested (see 4.2.7). 2.4.1 General
2.2.1 Ball or Roller Bearings Frame and bearing housings should be examined
Bearing housing and shaft bearing fits should be for defects. Cracks and breaks should be repaired
measured and compared to design specifications and fits restored to manufacturer’s specifications.
(Reference: ANSI/ABMA Stds. 7 as a guide). Any 2.4.2 Mounting Surface Tolerances,
fits that are not within tolerance should be restored. Eccentricity and Face Runout
See Tables 2-13 and 2-14. Replacement bearings • NEMA Type C face-mounting motors and Type
should be equivalent to the original manufacturer’s D flange-mounting motors: See Table 2-8.
specifications unless redesigned by agreement with, • NEMA Type P flange-mounting motors: See
or at the instruction of the customer. Table 2-9.
2.2.2 Sleeve Bearings • IEC flange-mounted machines: See Table 2-10
The sleeve bearing fit in the housing and the and Table 2-11.
diametral clearance should be measured and set to 2.5 LAMINATED CORES
original equipment manufacturer’s specifications Examine stator and rotating element laminations
if available. Note: Not all sleeve bearing bores are for evidence of hot spots, physical damage or miss-
cylindrical. ing components.
2.2.2.1 Sleeve Bearing End-Thrust 2.5.1 Rotating Elements
Bearings of horizontal machines should be posi-
Inspect rotating element core for evidence of
tioned on the shaft to eliminate end-thrust against loose fit on the shaft, sleeve or spider on which the
either bearing.
lamination stack is assembled. The outer diameter
2.2.2.2 Oil Rings of the rotating element laminations should be true
Oil rings should be true and rotate freely. Retain- and concentric with the bearing journals.
ers, when provided, should be inspected and replaced
if necessary. 2.5.2 Stators
The stator laminations should not be loose in the
2.2.2.3 Seals frame. If applicable, the bore of the stator lamina-
Seal clearance should be set to original equipment tions should be true and concentric with the rabbet

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