VibrAlign Fixturlaser Go, Руководство по обучению

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U S I N G T H E R M A L T A R G E T S
TARGETS
Some equipment moves from its off-line (cold) position when it
is on-line and operating (hot). The most common cause of this
dynamic movement is thermal growth. For example, a 10-inch
long piece of carbon steel grows about 6.3 mils when heated
100°F above ambient conditions. (The coefficient of expansion
for carbon steel is 6.31X10e-6”/°F/in; 0.00000631" x 10" x
100°F = 6.31 mils). So most machines which get hot (or cold)
will grow in length. They grow away from fixed points. You
should be concerned mostly about vertical changes; however,
machines will move horizontally, vertically and axially.
TARGET VALUES IN THE GO
Most machines experience dynamic movement while
operating. The moveable and stationary components may
grow due to heat generated within the equipment, pipe strain
may affect movement, etc. In some applications it is necessary
to deliberately misalign the equipment when it is cold so it will
‘grow’ into proper alignment after reaching operating load
and temperature.
We can input target values in either of two ways: feet values or
coupling values (angle and offset). The Target Values program
is started from the alignment program by selecting the Target
Values icon and pressing OK. The Target Values program can
only be started after the dimensions are entered.
1. ENTERING FEET TARGET VALUES
1.1 Select the foot icon and press OK.
1.2 Select the smaller boxes to enter the foot dimensions.
All dimensions must be entered.
1.3 Select the larger boxes under the feet to enter target
values for the stationary and/or moveable feet.
If the machine grows vertically (a positive amount), the
machine should be set lower (a negative amount). That is,
if the moveable front feet are expected to grow +8 mils,
enter -8 mils in the box as the target value. Setting the feet
8 mils low ensures a proper alignment at operating load and
temperature.
1.4 Select OK to go the alignment job.
1.5 Proceed with the alignment as usual.
2. ENTERING COUPLING TARGET VALUES
2.1 Select the coupling icon.
2.2 Select the input boxes to enter the angularity (mils/
in) and offset (mils) target values.
Make sure you have the correct sign on the values by looking
at the coupling icons. Positive angularity values mean the
coupling gap is larger at the bottom. Positive offset values
mean the moveable machine will be left higher than the
stationary machine.
2.3 Select OK to go the alignment job.
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