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
