Comparison of torque standards from 0,1 N⋅m at 50 N⋅m
Project Description
LNE has two reference torque machines with capacities of 5 N⋅m and 50 N⋅m. These machines will be compared with the corresponding machines of PTB. The measurements will be used to support torque capability claims of LNE. Uncertainties of the LNE 5 N⋅m reference torque machine in the range from 0,1 N⋅m to 5 N⋅m are:
± (0,20 mN⋅m + 5⋅10-5⋅T) (k=2). Uncertainties of the LNE 50 N⋅m reference torque machine in the range from 1 N⋅m to 50 N⋅m are: ± (0,50 mN⋅m + 5⋅10-5⋅ T) (k=2).
The pilot lab will be PTB (Germany).
Progress Report 2023-09-04
LNE has 2 reference torque machine with capacities of 5 N m and 50 N m. The LNE 5 N m and 50 N m machines were compared with the corresponding machines of PTB. Draft A has been sent to PTB and LNE is working on the modifications following the comments from the PTB.
Progress Report 2022-06-02
The measurements have been completed, there are some problems with the required data. LNE and PTB are working on the clarification.
Progress Report 2021-02-01
LNE has 2 reference torque machines with capacities of 5 N·m and 50 N·m. The LNE 5 N·m and 50 N·m machines were compared with the corresponding machines of PTB. En-Value were above 1 for the new capability claims. It's means for LNE 5 N.m machine from 0,1 to 5 N.m : 0,20 mN.m + 5E-5 T and for the LNE 50 N.m from 1 to 50 N.m : 0,50 mN.m + 5E-5 T) (k=2). However, the with the actual LNE CMC En-Value is less than 0.3.The final report is planned for the beginning of this year.
Progress Report 2019-03-05
LNE has 2 reference torque machines with capacities of 5 N·m and 50 N·m. These machines will be compared with the corresponding machines of PTB. The measurements will be used to support torque (T) capability claims of LNE. Uncertainties of the LNE 5 N⋅m machine in the range from 0,1 to 5 N⋅m : 0,20 mN⋅m + 5⋅10-5 ⋅T and of the LNE 50 N⋅m from 1 to 50 N⋅m : 0,50 mN⋅m + 5⋅10-5⋅⋅ T) (k=2). The uncertainty which LNE claim can not be confirmed because of partly En-Values above 1 (up to 1,6). It's maybe due to the folding of LNE machine metal foils. We do complementary measurements at LNE and it's seems that the results have improved after changing metal foils. To be sure of that, PTB and LNE have to make other measurements. Also, the comparison was made with only one transducer per machine. To be sure that deviations are not due to systematic effect link to the transducer, good practice is to use at least two different brand and / or type sensors. So, we plan to extend the project. We plan to realize this measures when PTB will be able to do it, ie early 2020.
Progress Report 2017-05-09
Measurements are in progress, the first measurements at PTB with one of the two torquemeters have been carried out. The end of measurements is expected in September 2017.