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View Full Version : 2" Thin-Wall (Sch 200?) Balloned!


MEXANDME
03-10-2009, 07:01 AM
I had to do a repair on a 2" pressurized irrigation line the other day and it was "balloned" near a tee that I was replacing. A coupling would not fit over the old pipe once I cut it in two! Once I dug back further and cut off more old pipe, the coupling fit. This system is fed by city water but used to be fed by a golf course irrigation system. Could the high pressure from the golf course system have actually caused the pipe to "ballon" at the tee fitting? (I do not know exactly what type the 2" pipe is but it is thinner than SCH40.)

AI Inc
03-10-2009, 07:03 AM
Did it actualy balloon , or did it egg out of round?

MEXANDME
03-10-2009, 07:12 AM
No, it was not egg-shaped. That was the first thing I looked at. It was like the pipe was 1/32" or so too wide all the way around.

Dripit good
03-10-2009, 07:33 AM
Yea. PVC has the ability to balloon quite a bit before it bursts!

139283

AI Inc
03-10-2009, 07:44 AM
wow, looks like a friggen tumor.

AI Inc
03-10-2009, 07:50 AM
Drip , was that near a pump, was it heat related?

FIMCO-MEISTER
03-10-2009, 07:59 AM
MEX do you know what the allowable constant pressure on CLASS 200 pipe is? Not trying to trip you up but just curious.

DanaMac
03-10-2009, 08:09 AM
wow, looks like a friggen tumor.

In my best possible Arnold accent - "It's not a tumor".

Dripit good
03-10-2009, 08:10 AM
Drip , was that near a pump, was it heat related?

Yes sir. This came right out of the pump and 90'ed into the ground. Bad solenoid prevented flow. I'm thinking the water heated up, and with the increasing pressure ballooned (at it's weakest point) before bursting. If the prv didn't also fail, this wouldn't have happened. Changed it out to galvanized and replaced the prv. IMO it's still a ticking time bomb without mercoids.

Sprinkus
03-10-2009, 09:15 AM
Could be excessive velocity and/or pressure in the line that caused the problem. I've also seen that happen in areas where solvents, like paint thinner, or fuels, like gasoline and diesel, were spilled or dumped.
Excess glue and/or primer inside the pipe at the glue joint could also cause the same problem.

Sprinkus
03-10-2009, 09:27 AM
Yes sir. This came right out of the pump and 90'ed into the ground. Bad solenoid prevented flow. I'm thinking the water heated up, and with the increasing pressure ballooned (at it's weakest point) before bursting. If the prv didn't also fail, this wouldn't have happened. Changed it out to galvanized and replaced the prv. IMO it's still a ticking time bomb without mercoids.

I've used the Smart Box (http://www.munrocompanies.com/content/view/29/84/) on some of my recent pump installs. They have a version of it that includes a heat sensor, as well as the pressure sensor, and will shut the pump off if the water in the volute case gets too hot.

Wet_Boots
03-10-2009, 09:50 AM
Lightning strikes can also lead to the ballooning.

ARGOS
03-10-2009, 11:25 AM
Ballooning is also dangerous during lightning.

AI Inc
03-10-2009, 11:47 AM
Ballooning is also dangerous during lightning.

Wheres the expert, Dana around?

DanaMac
03-10-2009, 03:51 PM
Ballooning is also dangerous during lightning.

Sure is. No good pilot will fly if lightning is close. Now, I've flown through fog and dense clouds before with my pilot. Not the safest either. But if I wanted safe, I'd take up chess. Or Scrabble on Facebook :)

MEXANDME
03-10-2009, 05:36 PM
FIMCO - MEISTER,

To answer your question.....no, I do not.

Regards,

Ros

FIMCO-MEISTER
03-10-2009, 05:53 PM
FIMCO - MEISTER,

To answer your question.....no, I do not.

Regards,

Ros

The only thing I will say is that knowing those odd little factoids about pipe bursting strength, prs pressure, amps at a solenoid, etc etc may seem a big waste of memory space but they are great troubleshooting helpers.

For example you mentioned you had ballooned pipe. You mentioned city water/golf course water. You mentioned less than sch 40 pipe. Besides making the obvious repair a little cya is in order that you can manipulate for lots of future service work.

Do the repair...save the fitting...find the person who okays work...show them the fitting...throw some facts at them and explain that if the whole system is similar to this situation then we need to stay on top of it from a service point of view since it is highly likely there will be a repeat occurence. Might even be able to sell a master valve as upgrade to avoid having constant pressure on fittings that can't take the pressure being put on them.

Now I know from reading London Rain's post that you guys are susceptible to high water pressure which means you will go through valves much faster.

So much can be gleamed from a simple repair that can fill your calendar with work 2-3 more times a year.

Truly I was not trying to be a smartazz. I just wanted you to see beyond the repair for other opportunities.

Mike Leary
03-10-2009, 06:20 PM
a smartazz.

If you've got a system that has issues, you have to find the problem, not band-aid in a master valve, all that does is insure the leak does not happen in the day time. We've capped all the heads on a zone to find where the cheap-ass class 200 lateral had breached. On a suspected mainline leak, we leave the water on, hook up the 125cfm (wow, is that the earliest winterize post ever?) compressor and blow the pipe and fittings out of the ground, otherwise, you could spend forever looking for the leak. (See "521 Thread"). :)

irritation
03-10-2009, 06:25 PM
cheap-ass class 200

SDR 21 is the best for irrigation.:)

Mike Leary
03-10-2009, 06:35 PM
SDR 21 is the best for irrigation.:)

Don't get me started; you will never win; I have more time on my hands. Sch 40 rules.

MEXANDME
03-10-2009, 06:40 PM
FIMCO,

I did not take your answer as a smart -a answer. I sincerely appreciate your replies and tips. I have learned so much from from folks like you on this board. I am here to learn and again sincerely appreciate your help! (I did keep the pipe and shared it with the customer.)

Regards,

Ros

irritation
03-10-2009, 06:52 PM
Sch 40 rules.

Rules for friction loss.:laugh:

HokieAg07
03-10-2009, 07:42 PM
Don't get me started; you will never win; I have more time on my hands. Sch 40 rules.


Waste of plastic...

SCH40 is hardly ever spec'd around here...

Dont get me wrong SCH40 has its uses for certain things but not the whole system in this area. Nobody is going to pay for it, plain and simple.

Mike Leary
03-10-2009, 07:58 PM
Rules for friction loss.:laugh:

Yup, that and price; that's why all the pikers use that crappy pipe. :hammerhead:

irritation
03-10-2009, 08:05 PM
Yup, that and price; that's why all the pikers use it. :hammerhead:

Yea, higher friction loss, higher price = :jester:

Mike Leary
03-10-2009, 08:08 PM
:Yea, higher friction loss, higher price = :jester:

Huh huh, you think that's what it's all about? :hammerhead:

irritation
03-10-2009, 08:37 PM
No, there's more advantages using SDR 21. ;)

eagle irrigation
03-10-2009, 08:50 PM
bell end ?

Kiril
03-11-2009, 09:21 AM
Rules for friction loss.:laugh:

Not worth mentioning for dinky pipe systems, unless you find the additional loss of 1.53 psi / 100 at 12 GPM (1" distribution main) for SCH40 is really going to make a difference in the total cost of the system.

For dinky pipe, SCH40 is far more durable than class/sdr any day of the week and the difference in cost for most systems is negligible given the durability advantages one gains.

FIMCO-MEISTER
03-11-2009, 09:39 AM
Not worth mentioning for dinky pipe systems, unless you find the additional loss of 1.53 psi / 100 at 12 GPM (1" distribution main) for SCH40 is really going to make a difference in the total cost of the system.

For dinky pipe, SCH40 is far more durable than class/sdr any day of the week and the difference in cost for most systems is negligible given the durability advantages one gains.

The extra weight of sch 40 in large loads on trucks and vehicles all over the country is causing serious greenhouse gas problems besides the additional energy and petroleum in making it.

Fight globalwarmingclimatechangegreenhousegases use class 200 unless your constant pressure will exceed 100psi.

Kiril
03-11-2009, 09:44 AM
ROFL .... been talking to your daughter again I see.