TB 9-5120-202-24
9. Accuracy [20 in-oz to 12 in-lbs (192 in-oz)]
a. Performance Check
NOTE
Some torque wrenches/screwdrivers are only checked CCW, see appendix A.
(1) Exercise torque cell using method similar to step 7 q above.
(2) Exercise TI using method similar to step 7 r above.
(3) Attach TI with ranges of 20 in-oz to 12.5 in-lbs (200 in-oz) to torque tester.
(4) Slowly apply torque to TI in a clockwise direction for full-scale indication of TI.
(Do not over-torque torque tester.)
(5) Note reading on indicator then slowly release torque until only tare torque of TI
is applied.
(6) Repeat (3) and (4) above two more times.
(7) Compute average reading of indications in (4) above. If average reading is not
within limits specified in table 1 or appendix A for TI being calibrated, perform b below.
(8) Repeat (3) through (6) above at TI cardinal points of 20 and 60 percent of full-
scale if TI does not have a preset value.
b. Adjustments. Adjust in accordance with manufacturer's instruction manual.
NOTE
Some torque wrenches/screwdrivers do not have adjustments.
10. Accuracy (below 20 in-oz)
a. Performance Check
(1) Exercise torque cell using method similar to step 7 q above.
(2) Exercise TI using method similar to step 7 r above.
(3) Attach TI with range below 20 in-oz to low torque station.
(4) Slowly apply torque to TI in a clockwise direction for full-scale indication of TI.
(Do not over-torque low torque station.)
(5) Note reading on indicator then slowly release torque until only tare torque of TI
is applied.
(6) Repeat (3) and (4) above two more times.
(7) Compute average reading of indications in (4) above. If average reading is not
within limits specified in table 1 or appendix A for TI being calibrated, perform b below.