Electronics TSP-M, Инструкция по эксплуатации

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Measuring the Arc Height of a Peened Almen Strip
The following steps should be performed on the standard Almen strips and the mini-strips.
Step One
– Zero the Almen Gage
1. Push the ZERO/ON button to turn the gage “ON”.
2. Place the Zero Block on the gage with the indicator tip touching
the small side. Push the ZERO/ON button to achieve 0.000 mm in
the display.
Step Two – Perform Pre-Bow Compensation
If your shot peening procedure, such as process development or system
capability studies, requires higher intensity accuracy, pre-bow
compensation may be used. This technique can provide an additional
reduction in process uncertainty. A pre-bow compensation ensures that
only the net difference in arc height of a peened Almen strip is plotted on
a saturation curve. To perform pre-bow compensation:
1. Zero the Almen gage and then place the unpeened Almen strip on
the gage and record its value.
2. Be sure to note if value is positive or negative and write the value
on the opposite side of the strip.
3. Do not peen the side of the Almen strip with your handwritten
note.
4. A positive number is subtracted from the arc height reading
after the strip has been peened. A negative number is added
to the arc height reading after the strip has been peened.
For example:
a)
If the pre-bow is +2 and the arc height reading is 10,
the adjusted arc height reading is 8
b)
If the pre-bow is -2 and the arc height reading is 10,
the adjusted arc height reading is 12
In summary, most peening applications can tolerate the SAE J442
pre-bow bias of ±0.001” for N and A strips. If this tolerance level is
too high, you can apply the pre-bow compensation discussed
above.
Step Three – Measure the Arc Height
1. Place the peened Almen strip onto the measurement position with
the indicator tip touching the non-peened side (concave side) of the
strip. Record the value of the arc height shown in the display or, if using pre-bow compensation, the arc
height shown in the display with the pre-bow compensation applied.
2. Remove the strip and place it once again on the gage. Do this three (3) times to assure an accurate reading.
3. When finished, push and hold the M/OFF button for three (3) seconds to turn the gage “OFF”. (The gage
automatically turns “OFF” if it is not active for 15 minutes.)
Peened mini-strip placed on the mini-
strip gage. The reading is 0.199 mm.
Peened standard Almen strip placed
on the #2 Almen gage .