1. TORQUE STANDARDS AND DISSEMINATION: TORQUE APPLICATION FOR INDUSTRIES
Calibration of high-transmission torque tools (torque multipliers) with one-sided short support
TC3 RIO WORKSHOP 2006, September 19
Diedert Peschel, Working Group TORQUE, PTB, Germany,

2. APPLICATIONS of TORQUE MEASUREMENT
1 mN.m
100 mN.m
10 N.m
1 kN.m
100 kN.m
10 mN.m
1 N.m
100 N.m
10 kN.m
1 MN.m
Torque Scale at Physikalisch-Technische Bundesanstalt
20 kN.m
1,1 MN.m
safety engineering
off-shore-industrie
testing machines
screw and assembly technology
aircraft industry
shipbuilding
motor industy and power generation
medical measurements
automation engineering
technical viscometer
D. Peschel, PTB, Germany

3. Different types of application2

5. TORQUE AND TORQUE - IT IS NOT THE SAME
Important specific aspects in such applications are among others:
In case of using supported beams and adaptation of the test piece with couplings with low stiffness for bending the calibration will realised under pure torque conditions.
Unsupported beams generate additionally bending moment and side force so that the calibration conditions are very different from pure torque conditions. Supported beams generate the same problems, if there are not special adaptation parts to reduce side force and bending moments on the reference torque transducer.

6. Typically calibration stand at industry für torque multipliers
torque transducer

7. sin a = - sin (a+180)

8. Calibration equipment: basefame TB2-5-kN·m, U<0
Calibration equipment: basefame TB2-5-kN·m, U<0.05% TTS-1-kN·m, U<0.08% DMP40S2 or MGCplus different counter supports
F2max = 8 kN
F1max = 0,2 kN
M2max = 2 kN·m
M1max = 0,3 kN·m M1 F1 F2
-F2
-F1 M2

9. continuous measurement of transmission
planetary gearbox ratio: 1 : 11.5
continuous measurement of transmission
planetary gearbox ratio: 1 : 11.5
continuous measurements with loops

10. results of continuous calibration for different position of the planetary wheels

11. results: systematic deviation between the table values and calibration: 18% .....22%
random influence of the planetary gearbox:  5 %

12. Calibration Stand for Torque Tools up to 180 kN·m (PTB)
T10FH 300 kN·m
max. 100 kN

13. 0° A 180° reproducibility b for different positions <0.3% o.r.A 0°
180°
reproducibility b for different positions <0.3% o.r.
repeatability b‘ in the same position < 0.5% o.r.
exp. rel. uncertainty Wke (k=2) < 0.2% o.R.
systematic deviation fq = % o.f.s.

14. The described calibration equipment up to 5 kN·m is very compact and simple
Use reference transducer with small influence for parasitic mech. components
Use costumers torque wrench, elctronic torque wrench or reference torque wrench
By using reference torque wrench.
continious calibration is possible, in all other cases only step-by-step procedure
Wbmc < 1% typical for both calibration equipments

15. calibration procedure(s) for torque multipliers: next step after more experiences and discussion