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Pipe Location
4

Pipe Location

Pipe Location

(OP)
I'm interested in acquiring a pipe locator.  Specifically when copper tracer wire has been installed.  I've been looking at the Leica DigiCat and associated signal generator, but thought I'd see if anyone here has any suggestions/recommendations/experiences.  Thanks in advance.
 

RE: Pipe Location

Two rigid copper wires, one held in each hand.  No kidding.  I've seen it work many times.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: Pipe Location

That's dowsing for water.  I don't believe in that.  This works for pipe, at least big heavy steel pipe.  Of course you can also find swinging a magnet.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: Pipe Location

(OP)
I guess I should have clarified, the situation of interest is during the case of non-metallic pipe, with tracer wire.

RE: Pipe Location

The two rods work for any kind of pipe, with or without the tracer wire. They work for me all the time. I won a bet on finding the end of a clay pipe stub, 13 feet deep around one bend and 90 feet from the manhole. The rods cross on the pipe.If they put in a tracer wire, why didn't the engineer of record have an as-built drawnup.  

Richard A. Cornelius, P.E.
WWW.amlinereast.com

RE: Pipe Location

There you go! Exactly what I saw.  PEs can't lie.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: Pipe Location

I went and got my L-bent brazing rods out of the cabinet and threw them away, then went dumster diving when the theory was resurrected, so do I need to throw away again (this would confuse an educated person!>)

RE: Pipe Location

My Dad could dowse for pipes.  I never managed the trick.  He said it was because I just didn't believe hard enough (nor would I clap my hands).

If the electronic pipe locators work so darn well, how come the sparkies can't tell you where to dig for their buried cables?  Or, when they do, get it wrong by more than 10 or 15'?

Sorry, I shouldn't be in this forum, I know.  I'm just not civil enough.

RE: Pipe Location

For not being civil, you sure know how to slam it to the sparkies.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: Pipe Location

I believe and it works. However, I had a polish guy working for meand the rods turned out instead of in. Don't throw those rods out.

Richard A. Cornelius, P.E.
WWW.amlinereast.com

RE: Pipe Location

Reverse Polish notation.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: Pipe Location

BigInch,

Here is your chance to be a wealthy. All you have to do is prove to James Randi that your downsing technique works and you get a million dollars.

The JREF sponsors the famous million dollar challenge offering a prize of US $1,000,000 to anyone who can demonstrate evidence of any paranormal, supernatural or occult power or event, under test conditions agreed to by both parties.

Typical is what happened when James Randi tested some dowsers using a protocol they all agreed upon. If they could locate water in underground pipes at an 80% success rate they would get $10,000 (now the prize is over $1,000,000). All the dowsers failed the test, though each claimed to be highly successful in finding water using a variety of non-scientific instruments, including a pendulum. Says Randi, "the sad fact is that dowsers are no better at finding water than anyone else. Drill a well almost anywhere in an area where water is geologically possible, and you will find it."

http://www.skepdic.com/dowsing.html

RE: Pipe Location

OK, really I don't know if I could do it looking for water.  Those I witnessed were all looking for gas pipelines.

I also don't know if I would agree that its paranormal. Remember, I said he used two rigid copper wires.  That's definitely a scientific instrument.  What would Ben Franklin have thought about somebody calling his kite & key non-scientific instruments?  Don't dowsers actually use a forked willow switch?  I don't think that's scientific, but then again I'm not a botanist.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: Pipe Location

(OP)
I think this has turned out to be the most popular discussion I've ever started...even though it's gone in a completely different direction from what I was after.

RE: Pipe Location

Sorry for that.  Usually we try to stick to the question.  Apparently nobody checking in here so far has any experience with that specific device.  At least you got a general comment on the accuracy of these types of equipment not being too good, and maybe an option or two.  Got two copper wires?

Good Luck.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: Pipe Location

jartgo,

I'm no expert but I also think you need a generator to create the signal in the copper wires and then a detector to track the signal.

This link should take you to another manufacturer of these instruments - Radiodetection C.A.T (cable avoidance tool)

http://www.radiodetection.com/products_det.asp?sec_id=2690&art_id=5210

RE: Pipe Location

I've dowsed for lines and have it work as well as have it not work and I don't have a clue or even looked into the mystery.  I have a job right now where a utility is using this method and they have locates that are dead on as well as 20 feet off.

As far as the rods turning in or out.  I was told and shown by an older gentleman that they will turn one way if your hands are placed together with the palms touching and another way if the palms are facing you and the knuckles are touching.

As far as a real pipe locator, you can probably contact some of the local utilities (water, sewer, telephone, gas, cable) and see what they are using and how they like them.  The USA Blue Book and other water utility suppliers have several models that range in price from a few hundred to a few thousand dollars.  It all depends on what features you want.  They aren't hard to use and with a tracer wire deliver an accurate locate.

RE: Pipe Location

Of course, for really precision work, nothing beats a laborer with a shovel.

RE: Pipe Location

Sorry to keep kibitzing on this.  I should point out, my experience is anecdotal, and perhaps 10 years out of date at this point.  Most of the work done was on the "wet" side of Washington state, where ground water levels are pretty much at the surface most days (at least it was whenever it was me that had to be the shovel monkey).  Workers using these devices have told us that the ground water, or soil moisture content, tends to play hob with the propagation of the electrical signals.  I think there are some acoustical devices that work, and are somewhat more reliable in such conditions, but I have no experience with those.  Buried cable runs are now mandated by our local utility company to be backfilled with location tape attached to the conduit and run along the trench at 12-24" of backfill cover.   

RE: Pipe Location


It seems clear to me that using two copper rods (they call it "Witching" around here) is totally bogus. The claims are 2 bent wires can:

- locate concrete pipes, clay pipe, plastic pipes, power lines...anything, any material your worried about.
- It can locate water,
- No one can say how acurate it is,
- No one can tell you how deep it can detect things,
- It works better for some people than others,
- No one knows how it works.

People forget the times they get it wrong.  There's a driller I worked with that remembers all the things he didn't hit, but never mentions the phone lines he drilled through in our parking lot during an open house demonstration. (I watched him witch that spot - who needs a utility locate?)

With a few surface features people who have been around usually figure out how things are run, and can get it right on that alone a lot of time.  Lines aren't just randomly put in the ground  (Most of the time anyway).

I think witching is a poor and dangerous pratice.  
This would be a good one for mythbuster.







 

RE: Pipe Location

Nobody knows how pigons and salmon figure out how to get home either, but it doesn't stop them.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: Pipe Location

Getting back to the OP (maybe we owe that just a little time!), I don't know any obvious reason the radio detection wires would not work, assuming of course one could find the leads, assuming that the wires are properly located with the pipe, and also assuming that they are originally and remain intact underground.  That however could be a lot of assuming in some field situations.  
A contractor a few years ago told me additionally that sometimes wires don't survive HDD pulls (at least with plastic pipe, as the pipe generally has a much higher pull rating than the wire, and the wire is also fully exposed outside the pipe).  While I understand some special high-strength and armored wires are available at some extra cost, they still have quite small allowable pulling load compared to pipe ratings, and generally must still be exposed.    

RE: Pipe Location

jartgo,

We use a Metrotech 810 for our line locates when using tracer wire.  It works very well and will provide you horizontal location as well as depth to wire.  Having a good understanding of signal strength and capabilities is very important when using one of these machines.  If there are other utilities, such as gas, phone, power, etc. that are in close proximity or crossing with little vertical separation, the signal can sometimes bleed off to these other utilities.

I have used the two copper/brass rods and have been about 50% successful.  We usually only use this method when we are trying to find one of our water lines that is non-metalic and has no or broken tracer wire.  We always dig carefully with this method and call for locates first.

RE: Pipe Location

I only saw on line installed on the top of pipe. Then those pipe were buried.

I thought a lot portable equipments can detect those underground pipes. Usually burial depth shall be less than 3 to 4 meters.  

RE: Pipe Location

Had a co-worker a couple of decades ago.  A very astute engineer and scientist whose specialty was vibration analysis.  He did water-witching (dowsing) on the side.

He used bent coat hanger wires.

He maintained that it worked because the human body was a very sensitive indicator of magnetic permeability.  The dowsing rods are motion toggles that take small muscular movements and magnify them greatly.  He said that nearly anyone could do it, and that special powers or ability weren't required.

I was very skeptical.  One day, several of us went in to the parking lot of our building in the area where the water service lines presumabley came in.  Several of us "unconvinced" walked over a certain area and the wires crossed.  I was unaware of any predjudice on my part (but who can say wheter suggestability caused it).

One time the company was digging for some large pipes that weren't where the drawings said they were.  This fellow told them where to dig after dowsing, and the pipes were right where he said they were.

Was it all mere coincidence?  Who can say?
 

RE: Pipe Location

Thanks, Zambo (link to a story about arrest of a guy, they said "out on bail" selling devices to locate bombs, supposedly based on "dowsing" principle!)  [While stakes would appear to be generally a little higher in that field, I've heard some pipes can be like bombs].

RE: Pipe Location

Maybe it can find pipe bombs?

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

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