Old copper pipe diameter dilemma

[PeterTTT]

Over the very cold weather in winter an external cold water copper pipe burst.
It runs from my house to an outbuilding and has likely been in place for over 25 years. I measured the diameter roughly and it seemed close to 22mm.
I have cut the small hole section out and have tried fitting new 22mm copper in the section but the original pipe seems ever so slightly wider so the 22mm solder rings do not fit over the old pipe.
Looking online it seems the next size up from 22mm is 28mm but that seems too large a jump
Is there some old metric pipe diameter that might be closer to the 22mm?

Thanks
Peter

[GT03ROB]

Well 1 inch is just over 25mm

[simon_harris]

It will probably be an imperial pipe so 1" rather than 22mm.

Edited by simon_harris on Friday 5th May 16:31

[4Q]

3/4 is the imperial equivalent to 22mm. You can buy adapter connectors to go from one to the other.

https://www.bes.co.uk/3-4in-i-d-x-22-mm-imperial-t...

[Mr Pointy]

Old copper pipe of 22mm OD is probably 3/4":
https://ondemandsupplies.co.uk/what-type-or-size-w...

You can get adapters:
https://www.toolstation.com/made4trade-solder-ring...

[ARHarh]

If using compression joints you just need the correct size olives.

[PeterTTT]

Thansk very much for the hints .. will try sourcing the imperial sized olives

[4Q]

Any plumbers merchant should have them.

[JOldcastle]

Screwfix also do 3/4" to 22mm solder ring, I keep a few for emergencies as I only ever realise when I've already hacked out plenty of pipe....

[johnoz]

PeterTTT said:

Over the very cold weather in winter an external cold water copper pipe burst.
It runs from my house to an outbuilding and has likely been in place for over 25 years. I measured the diameter roughly and it seemed close to 22mm.
I have cut the small hole section out and have tried fitting new 22mm copper in the section but the original pipe seems ever so slightly wider so the 22mm solder rings do not fit over the old pipe.
Looking online it seems the next size up from 22mm is 28mm but that seems too large a jump
Is there some old metric pipe diameter that might be closer to the 22mm?

Thanks
Peter

If you have tried a 22mm olive on the pipe and it don't fit ie too big, there's no chance you will get a 3/4 to fit as it will be smaller.

22mm pipe is slightly bigger than old 3/4in pipe adaptors are required.

15mm pipe is marginally smaller than old 1/2in pipe you can usually use a 15mm joint it is a snug fit..

If your pipe has been frozen at some point and the ice has increased the pipe size hence it don't fit !! try cutting a larger section away you will find the right size again. I have seen this before especially near to where the pipe has burst.

[Huntsman]

johnoz said:

If you have tried a 22mm olive on the pipe and it don't fit ie too big, there's no chance you will get a 3/4 to fit as it will be smaller.

22mm pipe is slightly bigger than old 3/4in pipe adaptors are required.

15mm pipe is marginally smaller than old 1/2in pipe you can usually use a 15mm joint it is a snug fit..

If your pipe has been frozen at some point and the ice has increased the pipe size hence it don't fit !! try cutting a larger section away you will find the right size again. I have seen this before especially near to where the pipe has burst.

You've misunderstood what 3/4" pipe means.

Its nominal size is 3/4", the OD is 0.875". Sometimes referred to as Schedule K pipe.

[g7jtk]

You can even get a 22mm / 3/4” reducing socket

[Peanut Gallery]

My house froze a 15mm copper pipe, the actual hole that sprayed the water was about 1,5 cm long, however the copper for a good 15cm either side of the hole had stretched enough that I could not get the olives on.

In short, don't just try replace the broken 2" of pipe, replace a longer section.

[Sheepshanks]

Huntsman said:

johnoz said:

If you have tried a 22mm olive on the pipe and it don't fit ie too big, there's no chance you will get a 3/4 to fit as it will be smaller.

22mm pipe is slightly bigger than old 3/4in pipe adaptors are required.

15mm pipe is marginally smaller than old 1/2in pipe you can usually use a 15mm joint it is a snug fit..

If your pipe has been frozen at some point and the ice has increased the pipe size hence it don't fit !! try cutting a larger section away you will find the right size again. I have seen this before especially near to where the pipe has burst.

You've misunderstood what 3/4" pipe means.

Its nominal size is 3/4", the OD is 0.875". Sometimes referred to as Schedule K pipe.

No, he's right - 3/4" olives are smaller than 22mm. That's the point of them - 22mm olives won't tighten up on old 3/4" tube.

Bit of Googling says old imperial 3/4" pipe has OD 0.846 inch / 21.49 mm. Your 0.875" is slightly more than 22mm

So if a 22mm olive doesn't fit the pipe the OP has then there's some other issue.

[shtu]

johnoz said:

If your pipe has been frozen at some point and the ice has increased the pipe size hence it don't fit !! try cutting a larger section away you will find the right size again. I have seen this before especially near to where the pipe has burst.

That could well be the problem.

I had similar with 15mm pipe that had stretched a little, and no easy acess to cut back and replace - I managed to shrink it back using a pipe flaring tool to clamp and crimp the pipe back down to size.

[B'stard Child]

This might help

https://www.ebay.co.uk/itm/385577750075

Edited by B'stard Child on Tuesday 9th May 21:22

[Sheepshanks]

A 22mm flaring tool might be an idea, then the OP can solder 22mm pipe into the flared end.

[4Q]

3/4 fittings and 3/4 - 22mm adapters are commonly available from any plumbers merchants or even Screwfix & toolstation so why are people offering bizarre options like flaring the pipes?

[Sheepshanks]

4Q said:

3/4 fittings and 3/4 - 22mm adapters are commonly available from any plumbers merchants or even Screwfix & toolstation so why are people offering bizarre options like flaring the pipes?

…because the OP is describing a pipe that he can’t get a 22mm olive on to. If it was 3/4” a 22mm olive should be too loose to use.

[johnoz]

Sheepshanks said:

Huntsman said:

johnoz said:

If you have tried a 22mm olive on the pipe and it don't fit ie too big, there's no chance you will get a 3/4 to fit as it will be smaller.

22mm pipe is slightly bigger than old 3/4in pipe adaptors are required.

15mm pipe is marginally smaller than old 1/2in pipe you can usually use a 15mm joint it is a snug fit..

If your pipe has been frozen at some point and the ice has increased the pipe size hence it don't fit !! try cutting a larger section away you will find the right size again. I have seen this before especially near to where the pipe has burst.

You've misunderstood what 3/4" pipe means.

Its nominal size is 3/4", the OD is 0.875". Sometimes referred to as Schedule K pipe.

No, he's right - 3/4" olives are smaller than 22mm. That's the point of them - 22mm olives won't tighten up on old 3/4" tube.

Bit of Googling says old imperial 3/4" pipe has OD 0.846 inch / 21.49 mm. Your 0.875" is slightly more than 22mm

So if a 22mm olive doesn't fit the pipe the OP has then there's some other issue.

Thanks for understanding, I know what I said. Seen it, done it, sometimes things don’t have to be that difficult to fix.