water leak detector 1

[Keith1976]

Hi All;

I tried looking for the same thread but ended up with the helium stuff.

Most of the manufactures (RadCom, Gutermann) that produce underground water leak detector use noise corregulator principle. I would appreciate it very much if anybody can share his/her experience with me.

I doubt this product could really PINPOINT the leakage. I challenge one vendor: "you find the leakage for me and I will pay for your service according to the water loss at that point of leak". The salesman ran away, saying that he only sells product and not service.

Thanks and regards,
Keith

 

[PEDARRIN2]

I remember (in another life) there was a product we used for leak detection in double walled piping.

I believe Raychem made it. They are part of Tyco now or at least the heat trace part is.

I think the product was called trace-tek or something like that.

Not sure if it could pinpoint the leak though.

Might be a start.

 

[SteveWag]

The company I work for can located a leak on buried steel or cast iron within 5 feet or less if three metallic connections within about 500 feet of the leak. The leak must be over 30 or so GPM. Our locating equipment either work poorly or not at all on non-metallic pipe. The equipment uses time correlation between the three listening devices to pin-point the leak. The operators need a lot of time (experience) and there can be a lot of interference (multiple leaks, highway noise, power transformers).
Steve

 

[Keith1976]

I am refering to PVC pipe,steel pipe and PEpipe for water distribution, underground.

As STeveWag mentioned, the basic idea is to use correlation mathematical stuff. But I can't see its reliable.

Keith

 

[Apakrat]

Once Hydrostatic tested 11 miles of 18" OD, 0.25 wall, X-40 pipe, newly buried in the sand bed South of Kermit, TX. Pressured through yield+, and then had to hold pressure with out loss, for a minimum of 24 hours.

At 24 hours, the tremendous sum of about 8 gallons had been added to maintain pressure. A repeat during the next 24 and 48 hours ruled out temperature influences.

One of those fancy sound detection devices was brought in and detected a leak at about the mid point of the pipe route.

A section of the pipe was replaced and the entire line again pressurized up and through a higher yield+ point. The pressure again was maintained for 24 hours revealing about a 3 gallon per day loss. The sound detecting device could not detect anything.

About 20 Backhoes with Operators were hired to remove ditch backfill to within about 1 ft on the top of the pipe. People walking the pipeline, with probing sticks, (survey laths), poked each side of the pipe, looking for a damp spot.

One of the pipe probing people we later nick named “Waddles”, stepped on a spot and sank to his knee near a location where he had just previously probed.

The line was then passed for operations tie-in, after a final yield+ pressuring and 24 hour holding with out loss.

Bethlehem Steel picked up the tab for a major portion of the costs associated to these flawed pipe.

At 74th year working on IR-One2 PhD from UHK - - -

 

[Keith1976]

Apakrat;

From you story, so this device works only on relatively big leak??????

Keith

 

[unclesyd]

Have you checked into GPR (Ground Penetrating Radar) to find your leaks.
I witnessed a short demonstration of a GPR on a plastic and CI line. The demonstration was cut short by a thunderstorm, but not before it had located two leaks. It was also used to map the pipe line for about 1500 ft prior to locating the leaks.

 

[Keith1976]

Unclesyd;

GPR is for the third step in leakage management, isnt it? it is used to pinpoint the leakage.

Does anyone have expereince with Gutermann's Zonescan800.

Keith

 

[Apakrat]

Sorry for the delay in getting back to Your question Keith1976, about leak size.

If a total of 24 gallons in 72 hours, with pressure maintained above 1100 psi, is considered a "relatively big leak", then I suppose the answer would be yes.

Just want to also mention that the device was considered ineffectual during wind conditions approaching 10 mph or more and stand-by time was expensive.

Sure wish Ground Penetrating Radar had been available in my testing days.

At 74th year working on IR-One2 PhD from UHK - - -