MDPE Stopcock

[qubit]

Hello can someone please help me here I've got a MDPE stopcock (25mm MDPE to 15mm copper) and tried every method I can think of to connect it but each time there's always a small leak it's driving me nuts I've been trying all day please someone explain there's an olive type thing on the MDPE side but it's got a small manufactured gap in it I don't get it the standard olives don't have gaps in them this has a plastic O ring but that only protects one side and the olive type thing doesn't even go over the 25mm pipe it's about a mm short all round (it only goes over the end of the pipe insert) I tried stretching it but broke one previously and had to get a whole new stopcock this is driving me nuts the plumbers I asked said they don't deal with MDPE and there were no instructions with the taps please someone help me pleeeeeeeeeeease

 

[cider]

Hello can someone please help me here I've got a MDPE stopcock (25mm MDPE to 15mm copper) and tried every method I can think of to connect it but each time there's always a small leak it's driving me nuts I've been trying all day please someone explain there's an olive type thing on the MDPE side but it's got a small manufactured gap in it I don't get it the standard olives don't have gaps in them this has a plastic O ring but that only protects one side and the olive type thing doesn't even go over the 25mm pipe it's about a mm short all round (it only goes over the end of the pipe insert) I tried stretching it but broke one previously and had to get a whole new stopcock this is driving me nuts the plumbers I asked said they don't deal with MDPE and there were no instructions with the taps please someone help me pleeeeeeeeeeease

the olive with a gap thing is to stop the stop tap coming off the mdpe. needs to be pushed along pipe. it needs to have flat end against stop tap and the o ring creates seal. should be ok have u tightened with grips?

 

[seco services]

how can you have a small leak if you can't even get the olive on the pipe ?

 

[Softus]

Why isn't there one single full stop in your post?

tried every method I can think of to connect it but each time there's always a small leak

Where is the water appearing from?

please someone explain there's an olive type thing on the MDPE side but it's got a small manufactured gap in it

That isn't an olive; it's a grab wedge that retains the MDPE pipe.

this has a plastic O ring but that only protects one side

The joint is sealed by an O ring that doesn't usually come out of the fitting.

Please explain what you mean by "one side".

and the olive type thing doesn't even go over the 25mm pipe it's about a mm short all round (it only goes over the end of the pipe insert) I tried stretching it but broke one previously

If the grab wedge doesn't go over the MDPE pipe, then it's the wrong size for the pipe that you have.

If you couldn't get it over the pipe then have assembling the fitting without it?

Is the MDPE pipe brand new?

Have you checked it for scoring/scratching?

 

[qubit]

Thank you very much for your replies Mr Cider, Mr Services and Mr Softus I got the olive thing onto the end of the pipe insert which is slightly smaller than the pipe as you know which is how I assembled it when I got the leak (which allows the small gap in the grabber to let water through). What you have described is exactly how it should be that's how I thought it would be the grabber goes over the pipe but that's what drives me nuts the grabber simply doesn't go over the pipe but it's a 25mm pipe and a 25mm tap (I bought 2 different taps from 2 different places both cause the same problem the second was very expensive and said 25->15 on it) the nut goes over the pipe perfectly it's just the damn grabber I measured it also it's a mm too short all round I stretched one with a spanner and it broke has this happened to anyone else how do you get round it? Oh sorry for the lack of commas , greatly appreciate your help

 

[Softus]

OK. To start with I can't read your post unless I do this with it:

Thank you very much for your replies Mr Cider, Mr Services and Mr Softus.

I got the olive thing onto the end of the pipe insert which is slightly smaller than the pipe as you know, which is how I assembled it when I got the leak (which allows the small gap in the grabber to let water through).

What you have described is exactly how it should be that's how I thought it would be.

The grabber goes over the pipe but that's what drives me nuts - the grabber simply doesn't go over the pipe. It's a 25mm pipe and a 25mm tap (I bought 2 different taps from 2 different places both cause the same problem. The second was very expensive and said 25->15 on it).

The nut goes over the pipe perfectly, it's just the damn grabber. I measured it also - it's a mm too short all round. I stretched one with a spanner and it broke. Has this happened to anyone else how do you get round it?

To answer your question: you get around it by not thinking that the grab ring is there to seal anything. The gap is deliberate. Don't try to stretch anything.

The seal is provided by the O ring inside the fitting. If the end of the pipe is cut cleanly and has an insert in, then it will push into the fitting. If the pipe is not scored then the O ring will seal onto it.

As with anything, it's much easier to do it right than wrong, so if the pipe is scratched, or deeply grazed, or if there's cr*p on it, or if the pipe end is jagged, or if the insert is missing, then all bets are off and you might as well not bother.

 

[qubit]

Thanks Mr Softus I understand your point that the wedge is not a seal it's for holding the tap on I totally agree but what I'm asking is is it supposed to be about 23mm when the pipe is 25mm it doesn't make sense to me it doesn't stretch so how can I get it over the pipe I've tried many times in your experience does the grab just slide straight over the pipe because it doesn't for me since it's 1-2mm too small thanks sir

 

[Softus]

1. What is the gap in the wedge in its resting state?

2. Is it possible to get the wedge ontpo the pipe without it snapping?

3. If so, what is the gap in the wedge when it's on the pipe?

 

[qubit]

1.Resting state - 5mm

2.It is but after much persuasion and effort it doesn't seem "natural"

3.About 9mm

But when the wedge is over the pipe it's so stretched out that the nut no longer slips over it so it cannot grip the tap at all so it's pointless this is nuts Aprreciate your help very much Mr Softus

 

[Softus]

Are you sure that the pipe is 25mm MDPE, and that you have the correct fitting to go onto it?

As far as the nut goes, I don't understand why you think it would go on after the grab wedge.

 

[cider]

1.Resting state - 5mm

2.It is but after much persuasion and effort it doesn't seem "natural"

3.About 9mm

But when the wedge is over the pipe it's so stretched out that the nut no longer slips over it so it cannot grip the tap at all so it's pointless this is nuts Aprreciate your help very much Mr Softus

sure you have'nt got blue polly for contaminated land? this is thicker externally with an aloy layer.

 

[cider]

1.Resting state - 5mm

2.It is but after much persuasion and effort it doesn't seem "natural"

3.About 9mm

But when the wedge is over the pipe it's so stretched out that the nut no longer slips over it so it cannot grip the tap at all so it's pointless this is nuts Aprreciate your help very much Mr Softus

sure you have'nt got blue polly for contaminated land? this is thicker externally with an aloy layer.

with a white line down pipe

 

[qubit]

Thank you very much Mr Softus and Mr Cider

The external diameter of the pipe is exactly 25mm and the internal about 20mm I've measured it a few times

It doesn't have a white line or any visible alloy plus I assume that would have been more expensive but this wasn't more expensive than standard

I'm 99.9% sure it's standard 25mm MDPE

The stoptap (one of them) says on it 25->15 and the pipe fits into it snugly and perfectly without the wedge or nut but when the wedge is used it all goes pear shaped (not literally)

Mr Softus I did slip the nut on the pipe first if the tap is then put on without the wedge it's all nice and perfect but once mains pressure is applied it would probaly fly off but when I put on the damn wedge it's so wide it doesn't allow the nut and tap to even touch horrendous

 

[Softus]

In that case cut off 4" from your 25mm MDPE pipe, then take it, and the stoptap, to your supplier, and ask them to show you how to assemble it.

 

[qubit]

Okay I might try that but I doubt those dopes will know what to do worth a try thanks very much for your help Mr Softus