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The latest tale of woe

The latest tale of woe

The latest tale of woe

(OP)
So, I have two 20 ton water tanks that are my only source of potable water. They are large and concrete. The genius who designed them put them on separate foundations, and put the pump in between them. The pump fills a header tank up the hill. Over the years the two foundations have moved relative to each other so the rigid pipe between each tank and the pump split cracked or broked. The previous owner fixed it with tape. And to be fair that repair has stood up for more than five years.

Sadly the other day someone touched the repair with a spade, and it now drips at a rate of perhaps a ton per week or month. Since this is my summer's water I have to fix it. Since there is no valve between the tank and the leak, I cannot turn it off. I cannot get a 20 ton tanker in empty for less than the cost of it bringing in new water, so there's no way I can offload much of the current water.

Ideally I'd like to fix it by merely wrapping the pipe in some magic waterproof substance that'll work under slight pressure. Then ideally some sort of waterproof jacket that can be wrapped around a pipe.

Nurses in Casualty are very good at this, why don't we have a plumbers equivalent? Plaster of paris springs to mind.

Anyway, I'm going to pick up some JB Weld Waterweld, and keep wrapping various forms of tape around it. When the tank drains I'll pull the horrid mess apart and do the job properly.

Luckily the second tank is unaffected by this so this is just one of life's irritations rather than a biggie.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: The latest tale of woe

"Ah, the sharks have him."

Just get some thin rubber, glue it to some plastic sheet. Tie some 1/2" PVC to the sheet and then poke the sheets down into the tanks over the outlets and they will suck-up against them sealing the outlet (classic holed boat saving trick). Then, put a couple of Ebay big ball valves in and either some flex hose or a repair coupling. Repair couplings have a slip seal joint and can slide down a pipe for many inches without leaking.

Keith Cress
kcress - http://www.flaminsystems.com

RE: The latest tale of woe

That plan will still work well. Use 20 foot sticks of cheap 1/2" PVC. In boats many many have been saved by just dragging a sail across the hole. It gets sucked in and the leak reduces so much that time is available to affect a fix.

Keith Cress
kcress - http://www.flaminsystems.com

RE: The latest tale of woe

Buy a big roll of black plastic (here in Kiwiland I am thinking of a roll of silage stack cover) & make a temporary holding pond. Otherwise a water pump capable of pumping the water back in fastener than it is flowing out, be it the leak or while installing the repair?

Do they really call them 20 ton water tanks in Oz over here it would be 20,000 litre tank.

RE: The latest tale of woe

Try 3M Marine sealant/adhesive 5200. Works on wet and underwater. Then wrap with Gorilla tape.

Ted

RE: The latest tale of woe

If you can see the outlet pipe from the top of the tank there are a number of devices you can use to insert an expanding plug to seal it off while you repair the pipe.

I'm kind of assuming that the current repair is doing half a job, but if you remove it to put on one of these clamps then it could pour out of the hole / crack?

These guys have many and various options for pipe sealing upstream your leak. https://www.petersenproducts.com/Plugs-Inflatable-...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: The latest tale of woe

What are the pipes that you're trying to repair made of?

RE: The latest tale of woe

Try Rustolium LeakSeal. It should get you by for a while.
Next time that the tanks are low you can try to plug the line from the inside and replace the outlet piping.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: The latest tale of woe

(OP)
MM Yup, just got a roll of silicon tape. That's today's first job.

I don't know how big the underlying leak is, since all I have at the moment is a weep through the layers of tape that were the old solution. So one exciting thing to do would be to unwind all the old tape, find out what the real problem is, and solve that. That will be the permanent fix, but entails more work than I can justify to retain the water in the tank, or mess about with 20ft poles and rubber sheet -which is a good idea in principle.

hydtools, a goo of some form is the next attempt at a bodge, I'll look around for 5200

MJ, I can't see if the rubber gasket wraps around the pipe which in context is what is needed. That's pretty much what I was hoping for, except that in Australia they are so expensive it's cheaper to lose all the water and fix it with a simple flexihose, which is what my permanent fix will be.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: The latest tale of woe

Greg; We'd love to see some photos of your "Off the Grid" home if that is possible.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: The latest tale of woe

Greg,
If all else fails and you have to salvage the water , you might want to talk to these people , https://www.turtlepac.com/products/collapsible-wat...
You may not want to buy one , but they may be able to tell you who has one near by who could loan or rent it to you.
B.E.

You are judged not by what you know, but by what you can do.

RE: The latest tale of woe

(OP)
Here's a pic, the water tanks are on the left, one is out of shot. The 'agricultural' sunshading is gone, as are the crazy purple curtains. Above the driveway is a garage and the sheds with solar panels on them and the water header tanks.

Here's the view from the front deck, we just sit there reading and listening to the birds and frogs. Note the mowing on the paddock, we are in a fire danger area.



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: The latest tale of woe

Thanks Greg. I like your digs.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: The latest tale of woe

Here in The Colonies, Wal-Mart carries 3M 5200 in ~3oz tubes for ~$5.

It has rather a strong odor while curing.
It's basically a filled single-component polyurethane.
5200 is an attractive bright white, and can be worked with a wet tool for a short time before it kicks.

It sticks to anything, even underwater.

Once cured, it emits no odor, and nothing will remove it except some serious heat.

Only death will remove it from your hands.

Mike Halloran
Pembroke Pines, FL, USA

RE: The latest tale of woe

(OP)
And the winner is... Tommy Tape, moltenmetal's silicon tape, VirtualLPS. Given that it is self amalgamating I was thinking of going old school and wrapping it in string as well. I'm going to experiment with wet tape and see if it can be held in place externally and seal.

Anyway the next exciting installment will be late January when I take a knife to the whole sorry mess and put a flexible joint in, unless it rains before then in a serious fashion.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: The latest tale of woe

When will the whole tank next freeze out?

If the tanks do not freeze solid naturally, then buy a few pounds of dry CO2 (pellets are easiest to use) and make a temporary freeze plug around the drain of BOTH tanks. Then cut the interconnection pipes away from both tanks downstream of the freeze plug, add a cutout valve on BOTH tanks, the pipe run from the cutout valves to the tee, the discharge pipe run from the tee to the load, and the final connections.

Liquid nitrogen is more fun than solid dry ice, but less safe. More expensive too, unless you're near a bull semen distributor.

RE: The latest tale of woe

Once you've cut the pipes, if the freeze plug ztarts leaking, ztuff some wadded up
White btread in the open end. That should give you time to install a valve, and will easily flush away when you don't need it anymore.

Mike Halloran
Pembroke Pines, FL, USA

RE: The latest tale of woe

I would have thought the easiest thing IS a long pole with some foam attached to the end. Once the pipe is cut, that foam would suck right to the outlet hole, allowing you to do whatever repair you needed.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: The latest tale of woe

Glad to be of service...you have a lovely place!

Wrapping the tape with string is a good idea- will keep it out of the sun and provide some external reinforcement.

Freeze plugs do work, as long as you do them in a way to avoid splitting the pipe. I would never freeze plug a piece of plastic pipe- the likelihood that you break off the entire frozen line while you attempt your repair is very high.

White bread plugs are meant for holding back water from an incompletely drained piece of copper pipe while you're effecting a repair- to hold just long enough for you to get it hot enough to solder. A white bread plug won't hold any pressure- it just keeps the dripping at bay so you aren't fighting the losing battle of trying to boil off the water as fast as it drips down toward your joint.

Once it's drained, installing block valves and flex lines will solve it properly.

RE: The latest tale of woe

(OP)
The tank outlet is a a standard piece of 2" cold water plumping pipe, plastic. it's embedded in the side of the concrete tank. It's 40 years old. I imagine that it may be getting brittle, so when i have the system apart I'll probably install an inner pipe and bodge that in place. At the moment I'm sticking with if it an't broke don't fix it. The second tank gives me a 3 month window to fix it if anything catastrophic happens to this one.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: The latest tale of woe

In my neck of the woods, you could just wait for it to freeze.

I've seen cryo freeze seals for power plant repairs.

RE: The latest tale of woe

Freeze plugging is done all the time- just not in plastic pipe..

RE: The latest tale of woe

Not just water.
I have seen the flow of molten glass controlled by freezing.
The glass flowed through a hole in a platinum disk that had a heating element cast in the disk.
By controlling the temperature of the disk, the amount of restriction due to glass freezing was controlled.
If the current was shut off completely the disk would eventually freeze over completely and stop the flow of molten glass.
An air hose was used to speed things up when shutting down the flow.

Bill
--------------------
"Why not the best?"
Jimmy Carter

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