Heavy Duty Balanced Opposed Compressors - Ariel Corporation

FOR MODELS: JGZ AND JGU SECTION 2 - COMPRESSOR INSTALLATION
• If dial indicator methods, are used, be sure that readings are repeatable.
• Correct for indicator arm sag.
• Check the crankshaft thrust, or end play, after any movements have been made. Both
the compressor and driver shafts should “float” either direction and hold position. If
the shafts resist float or “spring” back, the axial clearance must be corrected. See
Section 1 for allowable compressor crankshaft thrust clearance values.
• Confirm that the alignment is within tolerance by checking the face and rim TIR at the
coupling after all components are heat soaked.
When properly aligned, the forces on the connected equipment will be at a minimum. This will
result in a smooth running unit and long bearing life.
Cold Alignment
Align the compressor to the
driver taking into account the
difference in thermal growth
between the compressor and
driver, so the face and rim TIR
measurements at the coupling
will be within the Figure 2-2 limits
when equipment warms to
the normal operating temperatures.
Reference Figure 2-3 and
Table 2-3 for the compressor
centerline height change, based
on 6.5 x 10 -6 /°F (11.7 x 10 -6 /°C)
and a typical differential temperature
increase of 100°F
(55.6°C). For other significantly
different predicted differential
temperature increases, the thermal
growth value may be calculated
for the compressor. Refer
to the driver manufacturer’s
thermal growth prediction for
the driver differential temperature
increase to normal operating
temperature.
When larger compressors are
shipped with the crosshead
TABLE 2-3 TB Woods HSH/FSH Couplings - Angular TIR
Coupling Size Flange OD, In. (cm) Angular TIR, max., In. (mm)
105 29.25 (76.1) 0.0084 (0.21)
160 33.50 (85.1) 0.0096 (0.24)
Compressor
Centerline
HOT
Compressor
Centerline
COLD
FIGURE 2-3
Compressor
Thermal Growth
Thermal
Growth
TABLE 2-3 Typical Thermal Growth Predictions
Frame Model
THERMAL GROWTH
Inches (mm)
JGM:N:P:Q 0.006 (0.15)
JG:A:I 0.007 (0.18)
JGR:W:J 0.008 (0.20)
JGH:E:K:T 0.011 (0.28)
JGC:D 0.014 (0.36)
JGZ:U 0.016 (0.41)
KBB:V 0.018 (0.46)
JGB:V 0.020 (0.51)
guides removed, it may be desirable to align the frame to the driver prior to installing the
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