Did you know that the ISO6789 Standard which defines torque wrench calibrations has been updated?

The standard is now split into 2 Parts. Norbar is able to comply with both parts of the standard.

Part 1 – Torque wrenches will be supplied with a Declaration of Conformance.

Part 2 – Torque wrenches will be supplied with a Calibration Certificate (defines the accuracy uncertainties of the wrench in more detail).

All companies should check with their Quality documentation to ensure that they are getting the certification required for their business. For support and enquires, contact

Part 1 – ISO 6789-1:2017

Central Service Centre:

45-47 Raglan Ave
Edwardstown SA 5039

Tel: +61 (0)8 8292 9777

Mackay Service Centre

2/36 Transport Avenue
Paget QLD 4740

Tel: +61 7 4953 9000

Eastern Service Centre:

Unit 5/55 Donaldson Road
Rocklea QLD 4106

Tel: +61 (0)8 8292 9777

New Zealand Service Centre:

B3/269A, Mt Smart Rd Onehunga
Auckand 1061

Tel: +61 (0)8 8292 9777

Western Service Centre:

Unit 2, 22 Chullora Bend
Jandakot WA 6164

Tel: +61 (0)8 8292 9777

Part 2 – ISO 6789-1:2017

NATA Calibration Lab

45-47 Raglan Ave
Edwardstown SA 5039

Tel: +61 (0)8 8292 9777

Key Changes

Regardless of performing Part 1 or Part 2 of the standard the following 4 points apply:

1. Definition of torque range of the tools has been changed and testing must now be from the lowest indicated value on the scale

4. Minimum period for application of torque values (rate of loading time)

2. Application of torque

3. Avoidance of parasitic forces during testing

Frequently Asked Questions

Why did the standard change happen?
Revision to BS EN ISO 6789:2003 to take into account ISO requirements for calibration with greater emphasis on the inclusion of uncertainties, thereby allowing for the more stringent demands of higher tech applications or where absolute understanding of the tool is required.
How do I reduce parasitic forces (side loads)?
Norbar have introduced a patented counter balancing reaction post to reduce the parasitic forces associated with side loading a torque wrench, this features on the TWC400 and 1500 loaders as standard.
Can my ISO loader or TWL be upgraded to meet the requirements of BS EN ISO 6789:2017?
The IS01000/1500 and TWL1500 loaders do not have the automatic weight compensation of the new TWC and there is no factory upgrade planned for these loaders.
I have an IS01500 or a TWL which I bought before this change. Why did you sell it to me?
Up to the release of revised standard Norbar along with all other suppliers of torque loaders did not know when the release date would be. The design of the TWC has taken time to test and has been launched as soon as we were able. Prior to the release of the 2017 edition the loading equipment supplied by Norbar was suitable for working to BS EN ISO 6789:2003
If I remove and replace the FMT on my TWC with an angular offset will it affect my uncertainties?
This will not affect the uncertainties although in line with best practice consideration shall be given to replacing the transducer into the same position from which it was removed.
If I calibrate using the short length reaction arm why is there no counter balance?
We will address the issue after launch the of the Automated TWC.
Can I use my Protest with the TWC?
Yes, use adaptor plate 60323.
When using my T Box (ISO 6789:2017 part2) are the uncertainties recorded in any particular order e.g. Drive adaptor 1st?
The U/C data can be recorded in any order however Norbar as a best practice record the variation of the loading force (reaction position) last.
Why 2 parts?

Part 1 allows for the manufacture to produce a document of conformance in accordance to the standard, it also details how the tool should be checked and what measurement considerations should be applied. This gives you a DECLARATION OF CONFORMANCE

Example user aftermarket vehicle repairs/tyre fitting where knowing the tool is fit for purpose is paramount. Part 2 carries over part 1 measurement methods but includes detail of the uncertainties and associated tests which need to be factored in to produce a CERTIFICATE OF CALIBRATION.

Example user Aerospace industry/Medical industry where performance and understanding of the tool are paramount.

How to measure the 80% to 100% final application of torque
Norbar have updated the software on the T Box to indicate to the user whether the rate of torque increase meets the requirements of the ISO 6789:2017, T boxes sold prior to July 2017 can be upgraded. Contact for details
What will happen if I ignore the revised standard?
In order to comply as an accredited laboratory, the revised ISO 6789:2017 must to be adopted. For those who work to an in-house or another standard e.g. ASME B107.300-2010, nothing changes
How do I check and record uncertainties for adaptors, ratchets and handle point of contact and reproducibility in accordance with the requirements of the new standard?
How do I check and record uncertainties for adaptors, ratchets and handle point of contact and reproducibility in accordance with the requirements of the new standard?
If I have a transducer calibrated and its uncertainties change do I need to update my uncertainty budget within TDMS?
Yes, following a re-calibration of your transducer, the relevant fields need to be updated within TDMS, see the TDMS user manual for more detail.
Will my TTT/TST and transducer system work with the TWC?
Yes, but the defined time to load from 80% to 100% of target torque will not be measured. The Norbar T Box (post Aug 2017} will report this time and let the operator know if the torque has been applied Correctly.
Can I use my ETS torque transducer equipment with the TWC?
Yes, but the rate of rise from 80% to 100% of target torque will not be measured. This is a requirement of ISO 6789:2017, The ETS system is obsolete contact for options on available upgrade off
Norbar’s transducers are typically better than class 1 for the primary classification range as per BS7882:2008 (±0.5% reading from 20% to 100% of full scale). How will this translate to a maximum uncertainty interval required for EN ISO 6789 part 1 & 2?
For part 1 there is no translation required, as it refers to measurement error and not uncertainty interval. The existing classification system can be used to determine suitability.

See table below:

For Part 2, the uncertainty interval of a Norbar transducer will be typically <=±1.0 making it suitable for a calibration of a torque tool requiring a 4% expected maximum relative measurement uncertainty interval. However the following table may be used as a guide. The transducer needs to comply with the classification and corresponding uncertainty interval.

Talk to us about the ISO-6789 Standard Today!