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FIGURE 4 DOMESTIC GAS METER SPANNER SET TABLE 1 PARTS LIST WITH TIGHTENING TORQUES FOR FITTINGS WHERE ELASTOMERIC WASHERS ARE USED TO MAKE THE SEAL. TORQUE
FIGURES OBTAINED FROM BS746:2014 TABLE 1. SPANNER SIZES MATCHED TO WASHER SIZE ON INTENDED FITTINGS

Description Product Code EAN TORQUE SETTING (NM)* MM

Set 1014-017 5018695002426 N/A
30mm 1014-030 5018695002624 25 30MM
34mm 1014-034 5018695002631 25 34MM
36mm 1014-036 5018695002648 25 36MM
38mm 1014-038 5018695002655 25 42.5MM
42mm 1014-042 5018695002662 25 46MM
46mm 1014-046 5018695002679 25 48MM
48mm 1014-048 5018695002686 25 52MM
52mm 1014-052 5018695002693 35 60MM
60mm 1014-060 5018695002709 35 66MM
66mm 1014-066 5018695002716 45 66MM
70mm 1014-070 5018695002723 N/A (BSP THREAD) 70MM
Testing and development 80mm 1014-080 5018695002730 100 80.5MM
During field tests it became apparent very 85mm 1014-085 5018695002747 100 85.4MM
quickly that the angle of the drive bar in 86mm 1014-086 5018695002754 100 86MM
the set made the spanners likely to twist Wrench 1014-001 5018695002600 N/A 250MM
on application, so I instantly swapped it
for a standard ½in ratchet, bringing the Key 1014-002 5018695002617 N/A (BSP THREAD) 46.5MM A/F
effort back in line with the nut.
Now there was a ratchet in use, it
became unnecessary to have the eight- 2in meter union (86mm spanner) working with a metal-rubber-metal seal
pointed star, so the next version was to 100N/m can lead to leaks in high frequencies, and
have a ratchet drive and a square hole The decision was taken to upgrade given the softness of brass as a material is
to give a better fit. the thickness of the plate to 8mm, guaranteed to cause damage to the fitting.
Some spanners were a tight fit to providing some extra durability to With the continued drive for smart
their design, and due to manufacturing avoid breakages from overzealous/ meters, meter exchanges will continue
tolerances on the brass nuts, would not inexperienced fitters. to increase over the next five years. I
always fit. These sizes were adjusted to view this as the perfect opportunity to
suit and now provide a good fit across Finished tool promote a change in approach and to
the whole range of unions and adaptors. At the end of the design and testing ensure that future engineers will be
Similarly, the key fitting was on the process, we were left with a lightweight working on installations that are leak
snug side, so this was adjusted too, and tool that could be used in tight spaces, free, easier and safer to work on. This
a short drive extension added to allow in excess of 270 degrees rotation should made installers more confident
easier access down into the fitting with around the fitting thanks to the ratchet, in their connections to meters on
the key attached. A smaller box was eliminating slipping and damage to completion of the job.
sourced and a better layout designed to brass nuts and decreasing the chances With this tool, I believe we’ve taken
keep the spanners secure in the box. of overtightening with a shorter lever. a step towards how things should
We thought it would be worthwhile to With the addition of a short inline be done, rather than accepting the
carry out some destructive testing on the torque adaptor, the force applied can be way things are, and hopefully we can
spanners, which provided results well read out whilst installing, helping less continue to look for new innovations to
in excess of the max strength test figures experienced engineers to develop a feel make gas safer for everyone.
stated in BS746:2014, but we did see the for the correct tightening torque.
potential for breakage if used incorrectly. There is an option for the set to be
scaled down for domestic meters only
Testing results were as follows: (up to U16), to keep costs and weight References
52mm spanner – stretched/broke down for the domestic engineer’s BS746:2014 – Specification for gas meter unions
and adaptors
at 135N/m toolset. This is also in final packaging,
80mm spanner – stretched/broke mimicking the style of the full set. Acknowledgements
at 190N/m
86mm spanner – stretched/broke Conclusion Thanks to the following people and organisations
whose support made the development possible:
at 190 N/m The thinking behind the development Deep Valecha, Operations Director, Regent Gas,
of this tool is an attempt to change the for sponsoring the development and patent filing
Torque setting (BS746:2014 Table way that gas engineers approach their for the invention; Phil Casper, Managing Director
of PJ Casper Associates and consultant to EMS,
1 - Requirements for leak testing of installations. for mentorship throughout the project; Maun
elastomeric washers): There is a widespread belief among Industries for their expertise and commitment to
1in meter union (52mm spanner) many installers that ‘the tighter, the the development, design and manufacture; EMS
subcontractors for field testing and feedback.
25N/m better’. That kind of attitude when

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