I'm cutting out a leaking ion-exchange unit at the pool equipment.

The local hardware store talked me into this funky repair pipe:
http://www5.picturepush.com/photo/a/...g/13335303.jpg

Have you ever used one of these funky things before?

On Jun 16, 6:52*pm, Danny D wrote:
I'm cutting out a leaking ion-exchange unit at the pool equipment.


Don't let any of the dilithium crystals spill out.....



The local hardware store talked me into this funky repair pipe:
*http://www5.picturepush.com/photo/a/...g/13335303.jpg

Have you ever used one of these funky things before?

No, and have no idea what it is, what it's purpose is, etc.

On Sun, 16 Jun 2013 22:52:04 +0000 (UTC), Danny D
wrote:

The local hardware store talked me into this funky repair pipe:
http://www5.picturepush.com/photo/a/...g/13335303.jpg

Have you ever used one of these funky things before?

Never saw one of those. You can make a PVC connection by other means.

How did they talk you into such a gadget?

On Sun, 16 Jun 2013 15:57:59 -0700, wrote:

Don't let any of the dilithium crystals spill out.....



No, and have no idea what it is, what it's purpose is, etc.

It's some kind of funky fancy no-fuss "slider" pipe.

I'm inclined to put the schedule 80 compression fitting in there (the
store didn't have any schedule 40 compression fittings), but the pipe is
so low to the ground, I might not have enough room.

That ion-exchange thing is a PITA - I can't even figure out how to
disconnect it - so I'm going brute force sawit out.
http://www2.picturepush.com/photo/a/...g/13335395.jpg

Why do they put these things in there anyway?

On Sun, 16 Jun 2013 16:21:07 -0700, Oren wrote:

How did they talk you into such a gadget?

They didn't have any schedule 40 unions in stock!

I'm sawing out the leaking ion-exchange thingey, so, I'll let you
know how it works (if I use it, and not the schedule 80 union).

On Mon, 17 Jun 2013 00:07:22 +0000 (UTC), Danny D
wrote:

That ion-exchange thing is a PITA - I can't even figure out how to
disconnect it - so I'm going brute force sawit out.
http://www2.picturepush.com/photo/a/...g/13335395.jpg

Why do they put these things in there anyway?

They do it for money, Danny. You know that. They oversold the buyer
for what was needed.

Use a blackboard and chalk. It looks like this; "$".

Everything centers around a dollar. You know that.

In ,
Danny D belched:
I'm cutting out a leaking ion-exchange unit at the pool equipment.

The local hardware store talked me into this funky repair pipe:
http://www5.picturepush.com/photo/a/...g/13335303.jpg

Have you ever used one of these funky things before?

I've used one on one of my pool connection with no issues

On Jun 16, 8:07*pm, Danny D wrote:
On Sun, 16 Jun 2013 15:57:59 -0700, wrote:
Don't let any of the dilithium crystals spill out.....

*

No, and have no idea what it is, what it's purpose is, etc.

It's some kind of funky fancy no-fuss "slider" pipe.

I'm inclined to put the schedule 80 compression fitting in there (the
store didn't have any schedule 40 compression fittings), but the pipe is
so low to the ground, I might not have enough room.

WTF is a Sched 80 or 40 "compression fitting"?

And what's wrong with normal PVC fittings that make them
unsuitable?

On 6/16/13 7:51 PM, wrote:
On Jun 16, 8:07 pm, Danny D wrote:
On Sun, 16 Jun 2013 15:57:59 -0700, wrote:

WTF is a Sched 80 or 40 "compression fitting"?

One of these, for example: http://tinyurl.com/kc3ly9u

And what's wrong with normal PVC fittings that make them
unsuitable?

The compression fitting was darn handy one time when I had to fix
an underground plastic pipe.

On 06/16/13 06:52 pm, Danny D wrote:
I'm cutting out a leaking ion-exchange unit at the pool equipment.

The local hardware store talked me into this funky repair pipe:
http://www5.picturepush.com/photo/a/...g/13335303.jpg

Have you ever used one of these funky things before?

Yes, I used one to repair the connection to the manifold of our
sprinkler system. Nobody talked me into it: as soon as I saw it, I knew
that it was what I needed to do the job in the simplest possible way.

Perce

On Sun, 16 Jun 2013 19:40:03 -0500, ChairMan wrote:

I've used one on one of my pool connection with no issues

Here is a picture of it collapsed and extended.
http://www5.picturepush.com/photo/a/...g/13335633.jpg

It seems to have an o-ring that prevents leaks.

On Sun, 16 Jun 2013 17:20:03 -0700, Oren wrote:

Why do they put these things in there anyway?

They do it for money, Danny. You know that. They oversold the buyer for
what was needed.

Yup. I don't disagree. The buyer seems to have paid for all the frills.

Funny thing though.

After paying for all the upgrades, they gave him steel bolts!
http://www5.picturepush.com/photo/a/...g/13335638.jpg

On Sun, 16 Jun 2013 21:38:01 -0400, "Percival P. Cassidy"
wrote:

On 06/16/13 06:52 pm, Danny D wrote:
I'm cutting out a leaking ion-exchange unit at the pool equipment.

The local hardware store talked me into this funky repair pipe:
http://www5.picturepush.com/photo/a/...g/13335303.jpg

Have you ever used one of these funky things before?

Yes, I used one to repair the connection to the manifold of our
sprinkler system. Nobody talked me into it: as soon as I saw it, I knew
that it was what I needed to do the job in the simplest possible way.

Perce

I'll make the assumption that your irrigation lines are not 2" PVC,
like the photo above.

My irrigation manifold is under ground in a irrigation box with cover.

Best move I ever made to avoid UV damage, etc....

On Sun, 16 Jun 2013 17:51:56 -0700, wrote:

WTF is a Sched 80 or 40 "compression fitting"?

Dean Hoffman showed a picture of the compression fittin:
http://tinyurl.com/kc3ly9u

But, I was mistaken by calling my fitting that; mine was a
schedule 80 union.
http://www4.picturepush.com/photo/a/...g/13335707.jpg

And what's wrong with normal PVC fittings that make them unsuitable?

Nothing. I just like being able to take things apart, if needed:
http://www2.picturepush.com/photo/a/...g/13335710.jpg

In ,
Danny D belched:
On Sun, 16 Jun 2013 19:40:03 -0500, ChairMan wrote:

I've used one on one of my pool connection with no issues

Here is a picture of it collapsed and extended.
http://www5.picturepush.com/photo/a/...g/13335633.jpg

It seems to have an o-ring that prevents leaks.

FYI: if you can, put a little waterproof grease on the o-ring before
assembly.
It helps make a better seal.
Mine leaked a bit for a couple days until it got a crud seal

On Mon, 17 Jun 2013 01:49:20 +0000, Danny D wrote:

It seems to have an o-ring that prevents leaks.

The o-ring in the funky fitting is in a different
place than in a union; so in the end, I opted for
the union (worried that the o-ring would leak).
http://www4.picturepush.com/photo/a/...g/13335712.jpg

On Sun, 16 Jun 2013 21:44:39 -0500, ChairMan wrote:

FYI: if you can, put a little waterproof grease on the o-ring before
assembly.
It helps make a better seal.
Mine leaked a bit for a couple days until it got a crud seal

I didn't like the way the funky fitting sealed.
The o-ring was on the end of the sliding pipe in the direction of the
flow of water ... whereas, with a union ... the o-ring is in the middle
of the screw-together connection, away from the direct flow of water.

With all that pressure, I was worried the funky tool would leak.
So, in the end, I opted for the schedule 80 union instead:
http://www5.picturepush.com/photo/a/...g/13335748.jpg

Danny D wrote:
On Sun, 16 Jun 2013 17:51:56 -0700, wrote:

WTF is a Sched 80 or 40 "compression fitting"?

Dean Hoffman showed a picture of the compression fittin:
http://tinyurl.com/kc3ly9u

But, I was mistaken by calling my fitting that; mine was a
schedule 80 union.
http://www4.picturepush.com/photo/a/...g/13335707.jpg

And what's wrong with normal PVC fittings that make them unsuitable?

Nothing. I just like being able to take things apart, if needed:
http://www2.picturepush.com/photo/a/...g/13335710.jpg

Compression fittings have the advantage of being replacable by themselves.
Unlike unions that you can't duplicate one side of when things fail years later.
Compression fittings have the disadvantage of becoming leaky easier than unions.

On Jun 16, 8:13*pm, Danny D wrote:
On Sun, 16 Jun 2013 21:44:39 -0500, ChairMan wrote:
FYI: *if you can, put a little waterproof grease on the o-ring before
assembly.
It helps make a better seal.
Mine leaked a bit for a couple days until it got *a crud seal

I didn't like the way the funky fitting sealed.
The o-ring was on the end of the sliding pipe in the direction of the
flow of water ... whereas, with a union ... the o-ring is in the middle
of the screw-together connection, away from the direct flow of water.

With all that pressure, I was worried the funky tool would leak.
So, in the end, I opted for the schedule 80 union instead:
*http://www5.picturepush.com/photo/a/...g/13335748.jpg

DADD-

omg...you're at it again!

Making a mountain out of a mole hill.....
injecting your substandard logic & experience into a simple situation,
dragging out the thread ad nauseum

I know you're close to SV....does Google not work in your area?

http://bit.ly/19cHvMs

The unit is a "telescoping coupling", a simple / effective means for
following application
.........
http://flexpvc.com/cart/agora.cgi?&p...es-Telescoping

S119-20 2 inch repair coupling, slip x slip
If you need to make a repair on pipe that is not easily moved, this is
what you need. Telescoping couple, 2" socket by 2" socket. One end
moves in and out to match up with existing pipe. Saves digging up the
whole pipe to make a repair. NSF Rated for potable water, pressure up
to 200PSI.

I've only installed two, the largest unit I've used is 3/4". Last one
installed in ~2005...no issues on either install.

Kinda like "Shark Bites"... might seem like magic but the design
concepts are sound

and in the age of internet, bad product performance would "blow back"
onto the mfr & sellers post haste.

Where I live, PVC unions have an O-ring in them so that if they ever leak, you simply replace the O-ring. It'll always be a standard AS568B dash size.



And, in my mind, that's a better design than brass or iron unions that rely on a precisely machined surface to prevent leaks. If you ever take a brass or iron union apart, you can never be sure it's not going to leak when you tighten that union back up. With an O-ring in the union, you never have any leaks, and even if you did, the probable cause would be a leaking O-ring and replacing the O-ring would fix the problem.

I'm cutting out a leaking ion-exchange unit at the pool equipment.

The local hardware store talked me into this funky repair pipe:
http://www5.picturepush.com/photo/a/...g/13335303.jpg

Have you ever used one of these funky things before?


*It looks like an expansion coupling. Probably just what you need to fit a
new piece in.

On Jun 16, 10:34*pm, Danny D wrote:
On Sun, 16 Jun 2013 17:51:56 -0700, wrote:
WTF is a Sched 80 or 40 "compression fitting"?

Dean Hoffman showed a picture of the compression fittin:
*http://tinyurl.com/kc3ly9u

So, it's like a Sharkbite. I didn't know they made them as
large as 2".



But, I was mistaken by calling my fitting that; mine was a
schedule 80 union.
*http://www4.picturepush.com/photo/a/...g/13335707.jpg

And what's wrong with normal PVC fittings that make them unsuitable?

Nothing. I just like being able to take things apart, if needed:
*http://www2.picturepush.com/photo/a/...g/13335710.jpg

And of course a "union" is a normal PVC fitting and you're not
using a compression fitting. I'll bet those 2" compression fittings
cost a fortune. I'm having a hard time imagining the
need to use one, versus say doing a repair using two 50cent
repair couplings and a piece of PVC pipe.

On Jun 16, 11:57*pm, "Bob F" wrote:
Danny D wrote:
On Sun, 16 Jun 2013 17:51:56 -0700, wrote:

WTF is a Sched 80 or 40 "compression fitting"?

Dean Hoffman showed a picture of the compression fittin:
http://tinyurl.com/kc3ly9u

But, I was mistaken by calling my fitting that; mine was a
schedule 80 union.
http://www4.picturepush.com/photo/a/...g/13335707.jpg

And what's wrong with normal PVC fittings that make them unsuitable?

Nothing. I just like being able to take things apart, if needed:
http://www2.picturepush.com/photo/a/...g/13335710.jpg

Compression fittings have the advantage of being replacable by themselves..
Unlike unions that you can't duplicate one side of when things fail years later.

So, what? If it fails, just replace the whole union. Are those
compression fittings meant to be taken apart and put back
together again many times, like a union?


Compression fittings have the disadvantage of becoming leaky easier than unions.- Hide quoted text -

- Show quoted text -

On Jun 17, 1:45*am, DD_BobK wrote:
On Jun 16, 8:13*pm, Danny D wrote:

On Sun, 16 Jun 2013 21:44:39 -0500, ChairMan wrote:
FYI: *if you can, put a little waterproof grease on the o-ring before
assembly.
It helps make a better seal.
Mine leaked a bit for a couple days until it got *a crud seal

I didn't like the way the funky fitting sealed.
The o-ring was on the end of the sliding pipe in the direction of the
flow of water ... whereas, with a union ... the o-ring is in the middle
of the screw-together connection, away from the direct flow of water.

With all that pressure, I was worried the funky tool would leak.
So, in the end, I opted for the schedule 80 union instead:
*http://www5.picturepush.com/photo/a/...g/13335748.jpg

DADD-

omg...you're at it again!

Making a mountain out of a mole hill.....
injecting your substandard logic & experience into a simple situation,
dragging out the thread ad nauseum

I know you're close to SV....does Google not work in your area?

http://bit.ly/19cHvMs

The unit is a "telescoping coupling", a simple / effective means for
following application
........http://flexpvc.com/cart/agora.cgi?&p...es-Telescoping

S119-20 2 inch repair coupling, slip x slip
If you need to make a repair on pipe that is not easily moved, this is
what you need. Telescoping couple, 2" socket by 2" socket. One end
moves in and out to match up with existing pipe. Saves digging up the
whole pipe to make a repair. NSF Rated for potable water, pressure up
to 200PSI.

I've only installed two, the largest unit I've used is 3/4". Last one
installed in ~2005...no issues on either install.

Kinda like "Shark Bites"... might seem like magic but the design
concepts are sound

and in the age of internet, bad product performance would "blow back"
onto the mfr & sellers post haste.

Still not sure what makes this so great versus a piece
of PVC and two repair couplings.

On 6/17/2013 or whenever, somebody wrote:


Compression fittings have the disadvantage of becoming leaky easier than unions.-


Difficult to imagine that that's the general case with compression
fittings. Aren't they generally used for waste pipe? i.e. no or very
low static pressure?

Personally I've only used them for plumbing a swimming pool filtration
system that included a heater. Obviously, outdoor installation, entire
system under pressure and subject to the elements. Once properly
aligned and snugged down leakage was never a problem.

Why? End of season you want to drain everything down, pull the pump for
winterization. Compression fittings like these made that a snap.

On Jun 17, 5:14*am, "
wrote:
On Jun 16, 11:57*pm, "Bob F" wrote:









Danny D wrote:
On Sun, 16 Jun 2013 17:51:56 -0700, wrote:

WTF is a Sched 80 or 40 "compression fitting"?

Dean Hoffman showed a picture of the compression fittin:
http://tinyurl.com/kc3ly9u

But, I was mistaken by calling my fitting that; mine was a
schedule 80 union.
http://www4.picturepush.com/photo/a/...g/13335707.jpg

And what's wrong with normal PVC fittings that make them unsuitable?

Nothing. I just like being able to take things apart, if needed:
http://www2.picturepush.com/photo/a/...g/13335710.jpg

Compression fittings have the advantage of being replacable by themselves.
Unlike unions that you can't duplicate one side of when things fail years later.

So, what? *If it fails, just replace the whole union. *Are those
compression fittings meant to be taken apart and put back
together again many times, like a union?







Compression fittings have the disadvantage of becoming leaky easier than unions.- Hide quoted text -

- Show quoted text -

I used one ot them (real name is "Dressler Coupling") to connect/
disconnect my irrigation puimp feeding out of a stram. Eventually it
'cold formed' the PVC pipe into a 'depression' where the gasket fit.
Took yeas to do it though. I don't think
I would ever use one on PVC pipe in a buried application. I do have a
couple of the galvanized ones in service, one over 20 oyears, with no
problems...yet.

Harry K

On Jun 17, 5:12*am, "
wrote:
On Jun 16, 10:34*pm, Danny D wrote:

On Sun, 16 Jun 2013 17:51:56 -0700, wrote:
WTF is a Sched 80 or 40 "compression fitting"?

Dean Hoffman showed a picture of the compression fittin:
*http://tinyurl.com/kc3ly9u

So, it's like a Sharkbite. *I didn't know they made them as
large as 2".



But, I was mistaken by calling my fitting that; mine was a
schedule 80 union.
*http://www4.picturepush.com/photo/a/...g/13335707.jpg

And what's wrong with normal PVC fittings that make them unsuitable?

Nothing. I just like being able to take things apart, if needed:
*http://www2.picturepush.com/photo/a/...g/13335710.jpg

And of course a "union" is a normal PVC fitting and you're not
using a compression fitting. *I'll bet those 2" compression fittings
cost a fortune. * I'm having a hard time imagining the
need to use one, versus say doing a repair using two 50cent
repair couplings and a piece of PVC pipe.

Normal repair couiplings require at least one of the two ends be
movable back and forth. A compression one
can be fitted if all you can do is move one of the pipes sideways.

Harry K

On Mon, 17 Jun 2013 05:12:18 -0700, wrote:

I'll bet those 2" compression fittings cost a fortune. I'm having a
hard time imagining the need to use one, versus say doing a repair using
two 50cent repair couplings and a piece of PVC pipe.

I agree. I did not buy a *compression fitting* (it was my mistake to use
that word). I bought a schedule 80 *union* (they don't seem to make them
in schedule 40 where I live) - and a funky slider slider coupling.

Googling, I find it's actually called an *expansion coupling"
http://www.troubleshooters.com/pool/...sion_Couplings

It's only rated at 200 psi though:
http://www.amazon.com/dp/B0069QVSB4

On Jun 17, 10:14*am, Harry K wrote:
On Jun 17, 5:12*am, "
wrote:





On Jun 16, 10:34*pm, Danny D wrote:

On Sun, 16 Jun 2013 17:51:56 -0700, wrote:
WTF is a Sched 80 or 40 "compression fitting"?

Dean Hoffman showed a picture of the compression fittin:
*http://tinyurl.com/kc3ly9u

So, it's like a Sharkbite. *I didn't know they made them as
large as 2".

But, I was mistaken by calling my fitting that; mine was a
schedule 80 union.
*http://www4.picturepush.com/photo/a/...g/13335707.jpg

And what's wrong with normal PVC fittings that make them unsuitable?

Nothing. I just like being able to take things apart, if needed:
*http://www2.picturepush.com/photo/a/...g/13335710.jpg

And of course a "union" is a normal PVC fitting and you're not
using a compression fitting. *I'll bet those 2" compression fittings
cost a fortune. * I'm having a hard time imagining the
need to use one, versus say doing a repair using two 50cent
repair couplings and a piece of PVC pipe.

Normal repair couiplings require at least one of the two ends be
movable back and forth. *A compression one
can be fitted if all you can do is move one of the pipes sideways.

Harry K- Hide quoted text -

- Show quoted text -

No, a repair coupling does not require that one of the pipes
move sideways. To replace a section of pipe with a hole,
you cut out that section. You cut a new piece of pipe about
1/4" shorter. You prime, put on glue. On the existing
pipe you only apply glue to the usual length. On the new
piece of pipe you apply primer/glue along enough of it so
that the repair couplings can be slid ALL THE WAY ON.
Put pipe in place, slide couplings half way back so that they
are now over the old pipe.

On Sun, 16 Jun 2013 22:45:29 -0700, DD_BobK wrote:

Kinda like "Shark Bites"... might seem like magic but the design
concepts are sound

I was looking for people's experience in using this "telescopic coupling"
aka *expansion coupling*.

It looks like the DIY pool repair guy here did exactly what I did:
http://www.troubleshooters.com/pool/repipe/

He *bought* the same coupling that I did; he took it apart, and looked at
where the single o-ring was - and given that it's on the *end* of the
slider pipe, he concluded, as I did, that it might not hold pressure as
well as a union would.

I find out here that even the really fancy ones with multiple Viton/EPDM
o-rings (over $300 each!) are rated only to about 235 PSI:
http://tinyurl.com/k5r6lyg

On Mon, 17 Jun 2013 05:18:41 -0700, wrote:

Still not sure what makes this so great versus a piece of PVC and two
repair couplings.

Now that I've taken the thing apart and compared it with a union, I think
that in certain applications they might be great. For example, if your
pipes *move* in use, and if you're below 200 psi, they might be useful.

Also, in my case, I knew I had limited clearance between the bottom of
the pipe and the concrete slab - so I had reasoned (in the store) that it
was "thinner" at its greatest width than a normal schedule 80 union was.

It turns out though that the schedule 80 union just about made it, so I
had room enough for that "fatter" union. Plus, when I took the expansion
coupling (aka telescopic coupling) apart, I was worried that the o-ring,
which goes around the end of the sliding pipe, was directly in the path
of the onrushing water - and I reasoned that it could cause turbulence
compared to the little nub on the inside of the union - and - worse yet -
it might leak since the o-ring is directly in the path of the onrushing
water.

Googling for the PSI of a 2 inch union, I am dismayed that they are only
pressure rated to 150 psi:
http://www.1pvc.com/PVC-schedule-40/...n-Slip-x-Slip/

So, I guess, in hindsight, *both* unions and expansion couplings don't
handle high PSI. (I forget what the PSI is in the pool pipes though.)

On Mon, 17 Jun 2013 07:21:48 -0400, John Grabowski wrote:

*It looks like an expansion coupling.
Probably just what you need to fit a new piece in.

I found out later that you are correct.
It's known as a 2-piece "expansion coupling" or "telescopic coupling".

Lowes sells them as:
CARLON 2-in Schedule 40 PVC Coupling Item #: 72268 | Model #: E945J-CAR

Apparently they're useful to "compensate for length changes due to
temperature variations".

In my case, there were no length changes over time; so it was overkill.

*It looks like an expansion coupling.
Probably just what you need to fit a new piece in.

I found out later that you are correct.
It's known as a 2-piece "expansion coupling" or "telescopic coupling".

Lowes sells them as:
CARLON 2-in Schedule 40 PVC Coupling Item #: 72268 | Model #: E945J-CAR

Apparently they're useful to "compensate for length changes due to
temperature variations".

In my case, there were no length changes over time; so it was overkill.


*The Carlon model is for electrical conduit only and is used for PVC
electrical conduit that is subjected to temperature variations because PVC
expands and contracts as the temperature changes.

On Mon, 17 Jun 2013 12:00:57 -0400, John Grabowski wrote:

*The Carlon model is for electrical conduit only and is used for PVC
electrical conduit that is subjected to temperature variations because
PVC expands and contracts as the temperature changes.

Ooops. My mistake.

I had googled for expansion couplings and I had not realized those that I
had found at Lowes (for half the price that I had had paid for mine) were
for electrical connectors. Thanks for pointing that out.

That also explains the low price (about $8), which alone should have
clued me in as mine was almost double that price.

So one of the cons of these 2" PVC (fluid) expansion couplings is cost.

On Mon, 17 Jun 2013 07:22:22 -0700, wrote:

To replace a section of pipe with a hole ...

I need to repair this hole, which was plugged by whomever removed the
automatic chlorine feeder; but it sometimes leaks:
http://www5.picturepush.com/photo/a/...g/13343398.jpg

I don't understand how it can be done, even after reading your
description. The 1/4 inch won't be enough.

I think you're saying to fix this, I can:
1. Cut out on both sides of the hole
2. Primer & cement on a coupling on both sides
3. Measure the pipe to fit between the couplings
(going 1.5 inches in both sides.
4. Subtract (you say 1/4 but I think it's 1.5 inches) from that
measurement
5. Put primer & cement on both ends of the new pipe
6. Shove the pipe all the way (1.5 inches) on one side
7. That just lets you get the pipe to touch the other side
8. Then center the pipe 3/4 inches on both sides

That's the only way I see that it can be done, and, even this method has
a problem that you can't shove the pipe straight in on the first side.

So I must be missing something on how to repair a section without a union.

On Sun, 16 Jun 2013 22:45:29 -0700, DD_BobK wrote:

If you need to make a repair on pipe that is not easily moved, this is
what you need. Telescoping couple, 2" socket by 2" socket.

Here is a picture of the o-ring location of the union versus the
telescopic slide:slide coupling:
http://www5.picturepush.com/photo/a/...g/13343518.jpg

Notice the location of the o-ring in the expansion coupling is in line
with the fluid, while that of the union is off to the side.

In ,
Danny D belched:
On Sun, 16 Jun 2013 22:45:29 -0700, DD_BobK wrote:

If you need to make a repair on pipe that is not easily moved, this
is what you need. Telescoping couple, 2" socket by 2" socket.

Here is a picture of the o-ring location of the union versus the
telescopic slide:slide coupling:
http://www5.picturepush.com/photo/a/...g/13343518.jpg

Notice the location of the o-ring in the expansion coupling is in line
with the fluid, while that of the union is off to the side.

you could have turned the expansion one around so that it flowed with the
water

On 6/17/13 9:11 AM, Harry K wrote:

I used one ot them (real name is "Dressler Coupling") to connect/
disconnect my irrigation puimp feeding out of a stram. Eventually it
'cold formed' the PVC pipe into a 'depression' where the gasket fit.
Took yeas to do it though. I don't think
I would ever use one on PVC pipe in a buried application. I do have a
couple of the galvanized ones in service, one over 20 oyears, with no
problems...yet.

Harry K


I used to see some on pipe for pivot irrigation systems. It's
been a long time ago though. Water supply pipe for pivots is usually
8" in the central U.S. There is some 10" but it's pretty uncommon
around here.
There really is no need for them since there is usually an elbow or
something one can remove to get pipe apart.

On Mon, 17 Jun 2013 21:16:48 -0500, ChairMan wrote:

you could have turned the expansion one around so that it
flowed with the water

That might help; but it's still inline with the water flow,
whereas the union is off the flow direction (AFAIK).

Still - that would have been a good idea had I used the
expansion coupling for the repair.

Next repair I'm going to try just couplings and pipes, to see
if it can be done without a union.

On Jun 17, 7:28*am, Danny D wrote:
On Sun, 16 Jun 2013 22:45:29 -0700, DD_BobK wrote:
Kinda like "Shark Bites"... might seem like magic but the design
concepts are sound

I was looking for people's experience in using this "telescopic coupling"
aka *expansion coupling*.

It looks like the DIY pool repair guy here did exactly what I did:
*http://www.troubleshooters.com/pool/repipe/

He *bought* the same coupling that I did; he took it apart, and looked at
where the single o-ring was - and given that it's on the *end* of the
slider pipe, he concluded, as I did, that it might not hold pressure as
well as a union would.

I find out here that even the really fancy ones with multiple Viton/EPDM
o-rings (over $300 each!) are rated only to about 235 PSI:
*http://tinyurl.com/k5r6lyg

DADD-

I guess the results of your "Googling" means that

flexpvc.com is wrong when they call the item a PVC-Couples-
Telescoping?

http://flexpvc.com/cart/agora.cgi?&p...es-Telescoping

btw 200psi isn't enough for your pool application?

Now that I've taken the thing apart and compared it with a union, I think
that in certain applications they might be great. For example, if
your
pipes *move* in use, and if you're below 200 psi, they might be
useful.

Totally awesome! DADD has pronounced the telescoping couple as "in
certain applications they might be great."
I'm certain the mfr will be glad to hear that & continue making them.

Question...got any idea of the operating pressure rating for 2" Sch 40
PVC pipe?

hmmm probably less than 200 psi

Question...got any idea of the operating pressure for a pool filter
system?

Question...got any idea of the length changes in a typical piping
system?