OK, this thread is as attractive to trolls as any, but for serious
discussion- what is the actual mechanism of a pipe cracking/bursting
due to the water freezing?

OK, we all know water expands when frozen, and this is the root of it,
but beyond that...
I'll sketch out what I believe the mechanism is using a series of
examples.

make a big "U" out of a copper pipe, like this:

| |
| |
-----------------------------------

fill that puppy with water. Freeze under the following conditions:

1) leave ends open, start freezing at middle, freeze whole pipe working
out towards the ends.
predicted outcome- no burst pipe

2) Leave right-hand end open, seal left-hand end. Freeze from left to
right
predicted outcome- no burst pipe

3) Leave right-hand end open, seal left-hand end. Freeze from right to
left
predicted outcome- burst pipe

4) leave both ends open. Freeze from ends towards middle.
Predicted outcome- burst pipe.

Further prediction: the point where the pipe cracks/bursts will be at a
point where there is water in the pipe, not ice.

Discuss.

Dave

wrote:

3) Leave right-hand end open, seal left-hand end. Freeze from right to
left
predicted outcome- burst pipe

4) leave both ends open. Freeze from ends towards middle.
Predicted outcome- burst pipe.

You forgot:

5) Put closed valve at one end. Freeze from middle or other end towards
valve. Burst pipe.

6) Put closed valves at both ends. Freeze from anywhere. Burst pipe.

More generally....block the pipe in two places, then start freezing the
enclosed water. It's got nowhere to go, so it bursts the pipe.

Chris

wrote:
OK, this thread is as attractive to trolls as any, but for serious
discussion- what is the actual mechanism of a pipe cracking/bursting
due to the water freezing?

OK, we all know water expands when frozen, and this is the root of it,
but beyond that...
I'll sketch out what I believe the mechanism is using a series of
examples.

make a big "U" out of a copper pipe, like this:

|
|
-----------------------------------

fill that puppy with water. Freeze under the following conditions:

1) leave ends open, start freezing at middle, freeze whole pipe
working out towards the ends.
predicted outcome- no burst pipe

2) Leave right-hand end open, seal left-hand end. Freeze from left to
right
predicted outcome- no burst pipe

3) Leave right-hand end open, seal left-hand end. Freeze from right to
left
predicted outcome- burst pipe

4) leave both ends open. Freeze from ends towards middle.
Predicted outcome- burst pipe.

Further prediction: the point where the pipe cracks/bursts will be at
a point where there is water in the pipe, not ice.

Discuss.

Dave

I assume you have a -reason- for this dissertation? IT's not exactly on
topic, after all and not even an analog for Home Repair??

wrote:
OK, this thread is as attractive to trolls as any, but for serious
discussion- what is the actual mechanism of a pipe cracking/bursting
due to the water freezing?

OK, we all know water expands when frozen, and this is the root of it,
but beyond that...
I'll sketch out what I believe the mechanism is using a series of
examples.

make a big "U" out of a copper pipe, like this:

| |
| |
-----------------------------------

fill that puppy with water. Freeze under the following conditions:

1) leave ends open, start freezing at middle, freeze whole pipe working
out towards the ends.
predicted outcome- no burst pipe

2) Leave right-hand end open, seal left-hand end. Freeze from left to
right
predicted outcome- no burst pipe

3) Leave right-hand end open, seal left-hand end. Freeze from right to
left
predicted outcome- burst pipe

4) leave both ends open. Freeze from ends towards middle.
Predicted outcome- burst pipe.

Further prediction: the point where the pipe cracks/bursts will be at a
point where there is water in the pipe, not ice.

Discuss.

Dave

As freezing conditions a not normally a 'point source' problem, it is
most likely that it will start to freeze over several feet of pipe.
Even with both ends open it is stillpossible to wind up with a broken
pipe. The interior of pipe is rough (galv) and you can get one or more
'ice plugs' and cause a burst between them.

Haryr K

wrote in news:1165274082.531707.280720
@n67g2000cwd.googlegroups.com:

OK, this thread is as attractive to trolls as any, but for serious
discussion- what is the actual mechanism of a pipe cracking/bursting
due to the water freezing?

OK, we all know water expands when frozen, and this is the root of it,
but beyond that...
I'll sketch out what I believe the mechanism is using a series of
examples.

make a big "U" out of a copper pipe, like this:

| |
| |
-----------------------------------

fill that puppy with water. Freeze under the following conditions:

1) leave ends open, start freezing at middle, freeze whole pipe working
out towards the ends.
predicted outcome- no burst pipe

2) Leave right-hand end open, seal left-hand end. Freeze from left to
right
predicted outcome- no burst pipe

3) Leave right-hand end open, seal left-hand end. Freeze from right to
left
predicted outcome- burst pipe

4) leave both ends open. Freeze from ends towards middle.
Predicted outcome- burst pipe.

Further prediction: the point where the pipe cracks/bursts will be at a
point where there is water in the pipe, not ice.

Discuss.

Dave



fill that puppy with water....


That's an awfully small dog.

Chris Friesen writes:

wrote:

3) Leave right-hand end open, seal left-hand end. Freeze from right to
left
predicted outcome- burst pipe
4) leave both ends open. Freeze from ends towards middle.
Predicted outcome- burst pipe.

You forgot:

5) Put closed valve at one end. Freeze from middle or other end
towards valve. Burst pipe.

6) Put closed valves at both ends. Freeze from anywhere. Burst pipe.

More generally....block the pipe in two places, then start freezing
the enclosed water. It's got nowhere to go, so it bursts the pipe.

I've seen some pipes that have burst.

Before the pipe bursts, is will swell up.
This forms a reservoir which only makes the problem
worse because there is more water to freeze the next
time and the plug can't move up or down the pipe.

I've seen a really big bulb in copper, maybe
2 inches on a half inch pipe.
Galvanized should swell less before breaking.

"Dan Espen" wrote in message
...
Chris Friesen writes:

wrote:

3) Leave right-hand end open, seal left-hand end. Freeze from right to
left
predicted outcome- burst pipe
4) leave both ends open. Freeze from ends towards middle.
Predicted outcome- burst pipe.

You forgot:

5) Put closed valve at one end. Freeze from middle or other end
towards valve. Burst pipe.

6) Put closed valves at both ends. Freeze from anywhere. Burst pipe.

More generally....block the pipe in two places, then start freezing
the enclosed water. It's got nowhere to go, so it bursts the pipe.

I've seen some pipes that have burst.

Before the pipe bursts, is will swell up.
This forms a reservoir which only makes the problem
worse because there is more water to freeze the next
time and the plug can't move up or down the pipe.

I've seen a really big bulb in copper, maybe
2 inches on a half inch pipe.
Galvanized should swell less before breaking.

I've seen stainless steel tubing 1/8" in dia balloon to about 1/2" for
approx 1" in length. This occurred over time as trapped water went through
many freeze/ thaw cycles before it finally split along the sausage like
aneurism. As a note, to illustrate the power of expanding ice, it takes
about 20,000 psi (tension) to cause such a failure. This actually happened
on a aircraft part and it was jet fuel that leaked out all over the rear of
the aircraft and onto the tarmac. If it wasn't noticed and the engines
started it would have blown everything sky high.
MLD

wrote:
OK, this thread is as attractive to trolls as any, but for serious
discussion- what is the actual mechanism of a pipe cracking/bursting
due to the water freezing?

OK, we all know water expands when frozen, and this is the root of it,
but beyond that...
I'll sketch out what I believe the mechanism is using a series of
examples.

make a big "U" out of a copper pipe, like this:

| |
| |
-----------------------------------

fill that puppy with water. Freeze under the following conditions:

1) leave ends open, start freezing at middle, freeze whole pipe working
out towards the ends.
predicted outcome- no burst pipe

2) Leave right-hand end open, seal left-hand end. Freeze from left to
right
predicted outcome- no burst pipe

3) Leave right-hand end open, seal left-hand end. Freeze from right to
left
predicted outcome- burst pipe

4) leave both ends open. Freeze from ends towards middle.
Predicted outcome- burst pipe.

Further prediction: the point where the pipe cracks/bursts will be at a
point where there is water in the pipe, not ice.

Discuss.

Dave


With the above conditions I would say that the pipe bursts at the last
point to have water - not "where there is water". Obviously the ice
expanding that breaks the pipe. If the section of pipe with water is
sealed from both ends, either valve or ice, it will break.

Perhaps one of the reasons that although I never blow out my sprinkler
lines I have never had a broken pipe. That and having black plastic.
The lines drain such that the only water is at the very end of the
lines. I expect that evaporates before it gets cold enough to freeze.

A couple years ago the feds mandated new faucets leak under the severe
pressure like over 10K PSI to minimize burst pipes when freezing.

it was a good idea. sorry i read this awhile ago but dont have a link