Imperial to metric olive - Which way?

[Marcus Jones]

Hello all. I’m replacing a stop tap which is connected to black alkathene and then feeds the flat in 1/2 inch copper. I’ve bought a 22mm stopcock, along with some imperial to metric olives. These are the ones which taper on the one edge. Which way do these go? Tapered edge INTO the 22mm fitting or the other way round? Thank you.

 

[Burger]

Marcus, I think the black alkathene is 22mm, so shouldn’t need imperial olive.

 

[Marcus Jones]

Marcus, I think the black alkathene is 22mm, so shouldn’t need imperial olive.

Really? Ok. Thanks. I’ll try a couple out once I’ve taken the old stopcock off. It’s in a block of flats that was probably built in the 60s/70s. Just out of interest, are you aware of the tapered/chamfered (one one side) olives that I’m referring to? Logic would suggest that the 2 matching edges (ie 22mm edge into the 22mm stopcock fitting) go together despite this being the opposite way we use rubber tapered washers in plastic compression waste fittings.

 

[townfanjon]

It sounds like 20 mm Alkathene, very hard to source them these days , you may have to go phillimac utc

 

[Marcus Jones]

Here are some photos of the olive and 22mm fitting. What is the general consensus on which way it goes into the fitting? Thanks

 

[Marcus Jones]

Here are some photos of the olive and 22mm fitting. What is the general consensus on which way it goes into the fitting? Thanks

View attachment 38424

View attachment 38425

I reckon it should be the bottom pic with the taper going into the fitting.

 

[Harvest Fields]

Marcus, I think the black alkathene is 22mm, so shouldn’t need imperial olive.

If the copper is 1/2” in the flat. A new stop tap will not fit as it will be 15mm

 

[Marcus Jones]

If the copper is 1/2” in the flat. A new stop tap will not fit as it will be 15mm

I know. I’ll be reducing from 22mm to 15mm to connect to the 1/2 inch copper.

 

[Best]

I reckon it should be the bottom pic with the taper going into the fitting.

Correct way is the bottom picture with the large taper into the fitting.
If I were you I would be wary of working with the black water pipe - and at flats you could flood a lot of properties.
Be sure to check the pipe has proper liner and that the olive is correct size and compressed into the pipe just right

 

[Marcus Jones]

Correct way is the bottom picture with the large taper into the fitting.
If I were you I would be wary of working with the black water pipe - and at flats you could flood a lot of properties.
Be sure to check the pipe has proper liner and that the olive is correct size and compressed into the pipe just right

Thanks. I know what you mean. It’s on the top floor too!

 

[Best]

Thanks. I know what you mean. It’s on the top floor too!

I avoid working in flats now. Existing work can be old or just badly done and I don’t want to risk my reputation on other people’s work that could flood several flats.

 

[Burger]

Really? Ok. Thanks. I’ll try a couple out once I’ve taken the old stopcock off. It’s in a block of flats that was probably built in the 60s/70s. Just out of interest, are you aware of the tapered/chamfered (one one side) olives that I’m referring to? Logic would suggest that the 2 matching edges (ie 22mm edge into the 22mm stopcock fitting) go together despite this being the opposite way we use rubber tapered washers in plastic compression waste fittings.

Yes I knew what you were referring to, I was just replying but realised the time and decided to go home. Yes the tapered edge into the fitting so the 22mm seals at 22 end of nut fitting.

 

[Burger]

If the copper is 1/2” in the flat. A new stop tap will not fit as it will be 15mm

Are you saying the black pipe will be 1/2”?

 

[Harvest Fields]

I know. I’ll be reducing from 22mm to 15mm to connect to the 1/2 inch copper.

15mm copper will not connect straight to 1/2” copper. You will need an old to new connector.

 

[Harvest Fields]

Are you saying the black pipe will be 1/2”?

No

 

[Marcus Jones]

Are you saying the black pipe will be 1/2”?

The black pipe is the incoming mains which then reduces down to either 15mm or 1/2 inch copper. Having mulled all this over, I’m considering abandoning the replacement of the stopcock and fitting a new 15mm stopcock further along.

 

[Harvest Fields]

The black pipe is the incoming mains which then reduces down to either 15mm or 1/2 inch copper. Having mulled all this over, I’m considering abandoning the replacement of the stopcock and fitting a new 15mm stopcock further along.

If you do this and you have 1/2” pipe you will need 2 x old to new connectors and some copper pipe.

 

[Marcus Jones]

If you do this and you have 1/2” pipe you will need 2 x old to new connectors and some copper pipe.

Thanks for the help. Much appreciated.

 

[sammathias]

15mm copper will not connect straight to 1/2” copper. You will need an old to new connector.

Yes it will?? I always just use a 15mm end feed coupling?

A 3/4 pipe will need an adapter old to new..

 

[Stigster]

15mm copper will not connect straight to 1/2” copper. You will need an old to new connector.

I've always found them to be so close in size that the fittings are interchangeable on the 15mm - 1/2". The 22mm - 3/4" are way out so need an adapter but you have problems with the 15 to imperial?

 

[Harvest Fields]

I've always found them to be so close in size that the fittings are interchangeable on the 15mm - 1/2". The 22mm - 3/4" are way out so need an adapter but you have problems with the 15 to imperial?

Never had one that went on properly, had to use the correct fitting

 

[Welder]

I've always found them to be so close in size that the fittings are interchangeable on the 15mm - 1/2". The 22mm - 3/4" are way out so need an adapter but you have problems with the 15 to imperial?

My experience is as yours Stig.
My take on the images is top. Why? Because the longer taper is far more accommodating of dia. Look at the short end. It is perfectly matched with the olive.
Just my two penneth 😉