Near Final Alignment; Hot Alignment Check - Carrier 17 Start Up & Operation Manual

Measurement — With dial set at zero in the top position,
rotate the shaft to which the indicator is attached 180 de-
grees. If the dial reading is plus, the shaft on which the but-
ton rests is low. If the reading is minus, the shaft on which
the button rests is high.
Never accept a single reading. Look for repeatability. Ro-
tate the shaft several times to see if the reading remains the
same. It is good practice to reverse the procedure and read
from zero at the bottom.
Always rotate the shafts in the same direction when tak-
ing readings. Backlash in the coupling teeth could cause some
differences.
Adjustment — Divide the total indicator reading by two to
obtain the exact amount of shaft offset. As illustrated in
Fig. 42, the indicator will read the total of A plus B but the
required shaft adjustment is only half of this as indicated
by C.
Add or remove identical amounts of shims at all footings
to bring the shaft to the proper elevation. Tighten all the hold-
down bolts and recheck the readings. Parallel alignment must
be within .002 TIR.
To correct parallel misalignment in plan, use a screw jack
and dial indicator as shown in Fig. 42. With a front hold-
down bolt as the pivot, move the rear of the equipment over.
Then, with the rear holddown bolt on the same side acting
as the pivot, move the front end of the equipment over by
the same amount.
FINAL ALIGNMENT — The procedures and tolerance re-
quirements for final alignment are the same as those de-
scribed in the Near Final Alignment section. Final alignment
is performed just prior to grouting and machine hot check.
All piping, including water and steam, must be completed,
but the water and refrigerant charges need not be in place.

HOT ALIGNMENT CHECK

General — When all machine components have reached op-
erating temperature (after running near full load for from 4
to 8 hours), a hot alignment check must be made. Hot align-
ment check may be made with couplings assembled or dis-
assembled.
Disassembled Couplings
1. Shut down machine.
2. With machine hot, quickly disassemble couplings.
3. Check angular and parallel alignment in plan and eleva-
tion as described in the Near Final Adjustment section.
Record the indicator readings (see page CL-12) and make
necessary adjustments to bring alignment within .002 TIR
and .00033 inches per in. of coupling face traverse (or in.
of indicator swing). Follow procedures described in the
Near Final Alignment section.
4. Reinstall couplings and run machine until it again reaches
operating temperature.
Fig. 42 — Correcting Parallel Misalignment
5. Repeat steps 1 through 4 until alignment remains within
specified tolerances.
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