Equalizer SG11TM, Руководство по эксплуатации и обслуживанию, Страница: 13 / 76

IM_SGM_07 11
5.3 Bolt Hole Measurement
To ensure a true measurement is taken,
hold the vernier calliper:
• Square to the flange face,
• In the middle of the bolt-hole.
It is important that the vernier calliper is held
in the middle of the bolt-hole, and not held
at an angle to the flange face, nor used on a
bolt-hole which is worn, damaged or
distorted, as these actions may result in the
selection of an incorrect size of collet.
To confirm that the bolt-hole is round, take
two separate measurements with the vernier
calliper turned through 90° between
measurements.
To read the measurement from the vernier
calliper, scan along the desired scale from
left to right. In this example, the major figure
is 60 mm, this is added to the minor figure
of 8 mm (indicated by where the vernier
scale aligns with the main scale), giving a
total measurement of 68 mm.
With a bolt-hole size of 68 mm, the operator
can determine which collet and tool is
appropriate to this flange by referring to
the table. For example: 68 mm falls within
the 63 mm minimum and 69 mm maximum
bolt-hole sizes.
Therefore, collet identification is M64 / 2½"
If the measurement contains fractions of a
millimetre the method of reading the vernier
calliper is slightly different. In this example,
the major figure is 40 mm (read in the same
way as previously described). The minor
figure is 7 mm (read to the left of the zero).
The fraction is 0.5 mm (read from where the
vernier scale lines up with the main scale).
This gives a total measurement of 47.5 mm.
Major
Figure Minor
Figure