TORQUE STANDARDS AND DISSEMINATION:TORQUE APPLICATION FOR INDUSTRIES

Diedert Peschel, Working Group TORQUE, PTB, Germany, www.ptb.de

TC3 RIO WORKSHOP 2006, September 19

Calibration of high-transmission torque tools (torque multipliers) with one-sided short support

D. Peschel, PTB, Germanywww.ptb.de

APPLICATIONS of TORQUE MEASUREMENTAPPLICATIONS 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

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

Different types of application

2

44

highwayman 2 kN·m

0

200

400

600

800

1000

1200

1400

1600

1800

2000

0 50 100 150 200 250

input in N·m

outp

ut in

N·m

table value

55

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.

66

Typically calibration stand at industry für torque multipliers

torque transducer

77-0,0015

-0,0010

-0,0005

0,0000

0,0005

0,0010

0,0015

0 60 120 180 240 300 360

axial rotation in deg

mV/

Vtransfer transducer 100 N∙m

radial load 30 N

210°30°

230°

50°

-0,025-0,020-0,015-0,010-0,0050,0000,0050,010

0,0150,0200,025

0° 90° 180° 270° 360°

angleposition of the transducer

zero

sign

al in

mV/

V

sin sin (+180)

88

Calibration equipment:

basefameTB2-5-kN·m, U<0.05%TTS-1-kN·m, U<0.08%

DMP40S2 or MGCplusdifferent counter supports

F2max = 8 kNF1max = 0,2 kNM2max = 2 kN·mM1max = 0,3 kN·m

F2

F1

-F1

-F2

M1

M2

99

continious measurements with loops

02468

101214161820

0 500 1000 1500 2000output in N·m

tran

smis

sion

rat

iocontinious measurement of transmission

02468

101214161820

0 500 1000 1500 2000output in N·m

tran

smis

sion

ratio

planetary gearbox ratio: 1 : 11.5

continuous measurement of transmission

planetary gearbox ratio: 1 : 11.5

continuous measurements with loops

1010

torque mulitplier in N·m

0

500

1000

1500

2000

2500

0 50 100 150 200 250

input in N·m

outp

ut in

N·m

0°

90°

180°

270°

tablevalue

torque multiplier (type highwayman)

7

8

9

10

0 50 100 150 200 250

input in N·m

trans

mis

sion

ratio

0°

90°

180°

270°

Table value

results of continuous calibration for different position of the planetary wheels

1111

results: systematic deviation between the table values and calibration: 18% .....22%

random influence of the planetary gearbox: 5 %

torque multiplier (type highwayman)

7

8

9

10

0 50 100 150 200 250

input in N·m

tran

smis

sion

ratio

0°

90°

180°

270°

Table value

1212

Calibration Stand for Torque Tools up to 180 kN·m (PTB)

max. 100 kN

75 kN·m

T10FH 300 kN·m

1313

deviation from reference value

-9

-8

-7

-6

-5

-4

-3

-2

-1

00 100 200 300 400 500 600 700 800

pressure in bar

devi

atio

n in

%

0°/1 0°/2

180°/1 180°/2

0 0A A

0°

180°

210°30°

230°

50°

-0,025-0,020-0,015-0,010

-0,0050,0000,0050,0100,0150,0200,025

0° 90° 180° 270° 360°

angleposition of the transducer

zero

sign

al in

mV/

V

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 = 7.5% o.f.s.

1414

• 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 procedureWbmc < 1% typical for both calibration equipments

1515

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