over tightening compression joint

[shezzar]

Today, I was connecting two pipes for a kitchen sink using a isolation valve. At the end of it when testing the pipes I looked and on top of both isolation valves there was a little bubble of water, so naturally i tried tightening them more and the bubble didnt stop (i did dry it beforehand)

I came to the conclusion that I have overtightened the joints. I had done alot of tightening both hands and spanner.

Would i be able to use the same isolation valve, but just change the olive, or would i have de-threaded it?

So the question is, what is the recomended way of tightening the compression joint?

I did hear after, that it is to do it hand tight and then a quater turn, is this correct?

I am considering putting a speedfit connection in, as the water connection to the tap is in plastic ( I did have the insert for compression fittings in the plastic end)

What would be the better way to do it, compression or plastic?

 

[Burnerman]

You may well have distorted the olive and pipe, but its worth splitting the joint, coating the olive in some jointing compound and then wrapping a few turns of PTFE tape around the olive before reassembling.....you may well get away with it!
If not, then cut the offending joint out, and replace with a short length of copper pipe....but of course push fittings are ok if you prefer.
John

 

[Agile]

A big problem is that for cost reasons the olives are mostly pretty hard brass now!

A better solution is to replace all olives with copper.

It does not apply to DIYers, but the gas taps from Toolstation ( probably Screwfix too ) are almost dangerous because its so difficult to get them to seal even if done up so tight there is a risk of stripping the threads.

Tony

 

[shezzar]

by copper do you mean solder??
Im not a 'diyer' im a trainee plumber (dont realy do compression joints) but im going to france next year and wanted to try and stay way from getting a torch until then as i think they use a different chemical to burn, also the plastic pipe was already in the house and wanted to save money so i didnt want to rip it all out.

 

[Agile]

I mean copper olive rather than brass!

In France they hard braze plumbing joints rather than soft soldering as we do here!

 

[longdogs]

Are you saying that you have used compression fittings onto plastic pipe? If so have you used inserts in the ends of the pipe?



http://www.speedfit.co.uk/Home/Prod...E-PIPE---ACCESSORIES/Inserts/TUBE-INSERT.aspx

 

[shezzar]

they are slowely getting used to soft soldering in france, the reason they hard soldered was because the pressure of water could range massively, but now most homes have a 3 bar limiter installed, so soft soldering can be used.

I am using the correct inserts, eg. the ones with the blue ring for plastic and the ones without the ring for compression joints (as in the post above).

 

[MrGassafe]

It does not apply to DIYers, but the gas taps from Toolstation ( probably Screwfix too ) are almost dangerous because its so difficult to get them to seal even if done up so tight there is a risk of stripping the threads.

Tony

Then surley if you have evidence that a fitting is dangerous and
not fit for purpose then you should submit a RIDDOR report and
not running down suppliers on a public forum!!!

 

[Porque223]

It may be worth it to buy or rent a torque wrench and tighten to the maker's specs.

Regarding running down any person or company, I'd be careful of libel but the defamed person or company must also show that they were damaged by the remarks.

IIRC, Weatherguard [who makes rain gutter materials] tried to sue the Topix forum over something like this. There must have been a dozen "John Does" named in that suit.
Some said they would no longer buy those products and so the plaintiff could show damages in the legal sense. Their case was made for them by these disgruntled posters.

 

[Dan Robinson]

It may be worth it to buy or rent a torque wrench and tighten to the maker's specs.

Regarding running down any person or company, I'd be careful of libel but the defamed person or company must also show that they were damaged by the remarks.

IIRC, Weatherguard [who makes rain gutter materials] tried to sue the Topix forum over something like this. There must have been a dozen "John Does" named in that suit.
Some said they would no longer buy those products and so the plaintiff could show damages in the legal sense. Their case was made for them by these disgruntled posters.

That reminds me... must check in with an old friend.

 

[hazetimesfive]

what does it say on b and q packaging?

sth like finger tight and quarter turn