TB 9-5210-210-24
IDENTIFICATION AND DESCRIPTION
1. Test Instrument Identification.
This bulletin provides instructions for the
calibration of Dial Indicators (General). The manufacturer's manuals were used as the
prime data source in compiling these instructions. The equipment being calibrated will be
referred to as the TI (test instrument) throughout this bulletin.
a. Model Variations. Variations among models are described in text.
b. Time and Technique. The time required for this calibration is approximately
0.5 hour for each TI using the physical technique.
2. Forms, Records, and Reports. Forms, records, and reports required for calibration
personnel at all levels are prescribed by TB 750-25.
3. Calibration Description. TI parameters and performance specifications which
pertain to this calibration are listed in table 1.
Table 1. Calibration Description.
Test instrument parameters
Performance specifications
Dial accuracy
Range: 0.0 to 6.0 inch
1 deviation in least graduation1 or per manufacturer's
Accuracy:
expanded uncertainty
1
Graduations resulting in a Tolerance Uncertainty Ratio (TUR) of less than 4:1 require DA Label 163 documentation.
EQUIPMENT REQUIREMENTS
calibration procedure. This equipment is issued with Secondary Transfer Calibration
Standards Sets, AN/GSM-286; AN/GSM-287; or AN/GSM-421. Alternate items may be
used by the calibrating activity. The items selected must be verified to perform
satisfactorily prior to use and must bear evidence of current calibration. The equipment
must meet or exceed the minimum use specifications listed in table 2. The accuracies listed
in table 2 provide a four-to-one ratio between the standard and TI. Where the four-to-one
ratio cannot be met, the actual accuracy of the equipment selected is shown in parentheses.
Table 2. Minimum Specifications of Equipment Required.
Manufacturer and model
Common name
Minimum use specifications
(part number)
Starrett, Model 716 (13589315)1
Range: 0.0000 to 6 in.
DIAL INDICATOR
CALIBRATOR
Accuracy: 0.0001 in. plus an additional
with 12 in. extension support shaft
0.0001 in. for each additional
1 in. travel2
Resolution: 0.00005 in.
1 Accuracy
greater than 0.0001 inch assigned to a Starrett Model 716 is not recognized by USATA.
For example, the second inch travel accuracy of Starrett 716 with extension shaft is 0.0002 in. for 2 inches of
2
dial indicator travel.
