Earth clamps

[Bob Eager]

I have to do some bonding of the pipes on our boiler; the manual says that the gas pipe, and the flow and return, should be cross bonded.

I've fitted countless earth clamps, and I do understand how to fit them. However, three small questions, just to make sure:

1) I've never fitted one to a gas pipe. Any special precautions to avoid damaging the pipe?

2) This has always bugged me. Does anyone have a tidy way of getting rid of the excess on the end of the strap? Cut it off and leave a sharp edge? Hide behind pipe?

3) The label. I've always fitted it on the securing bolt, under the locknut so that it doesn't flap around. I've seen it mentioned that it should just hang loose on the bolt. Does it matter anyway?

Thanks...

[visionset]

No just common mechanical empathy.

Why, are they on obvious display? If so that would bug me more.

Can't see that it does, I fir mine for best visibility according to location.

[Andrew Gabriel]

No. Obviously, avoid slipping and spearing it with the screwdriver or screwing the bolt down so far it presses on the pipe.

To answer both questions, the labels are usually designed so they can go either under the nut, or on the strap end. I usually do both -- one end under the nut and the strap holding the other end and folded back on itself.

[Bob Eager]

Thanks...I'll give it a try!

[Lobster]

Someone who knew the answer to (3) gave chapter and verse here on fixing the warning label, and pointed out that there was indeed a Proper Way - can't find the post though. ISTR it had to be done by bolting it through the hole in the label and not by passing the strap through the slot?

David

[Andy Wade]

That's what I've often done, but I did spot an article in a recent copy of the NICEIC magazine /Connections/ in which this is deemed to be wrong. Apparently the label should not be left in contact with the strap, due to the risk of electrolytic corrosion. The slots in the strap are only for packaging and storage, it says.

This doesn't appear to be on their Web site yet, so I've put a quick scan of the article up at

(397 KB).

I can't help thinking that they're being just a wee bit anal about this:

(a) it's only going to corrode in damp locations, which could include storage;

(b) it ignores the fact that the label is always in contact with dissimilar metals between the clamp body an the lock nut;

(c) everybody knows what an earth clamp is anyway, so corrosion of the label is hardly a major issue.

[Andrew Gabriel]

I've seen plenty more which have been snapped off by getting caught on something than by any corrosion (none, I think).

[Bob Eager]

Yes, that's the place I was looking at. But they say to let the label flap loose and not put it under the locking nut...

I did, anyway.

[Andy Wade]

Or deliberately, even.

Precisely.

[Owain]

(d) The NICEIC don't make the Regulations anyway and if they were genuinely interested in safety they wouldn't have supported Part Pee.

Owain

[Owain]

(d) The NICEIC don't make the Regulations anyway and if they were genuinely interested in safety they wouldn't have supported Part Pee.

Owain