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because you cant answer it, nothing new..so you want to cause it by wrapping copper to a galvanized pipe...its hard to argue wits with some one that comes unarmed like yourself...:vs_laugh::vs_laugh::vs_laugh:
Failed heater inspection.
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Metal on metal in and of itself does not cause galvanic reaction. If I am unarmed you brought a gun missing a couple parts to a fist fight.
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you said you were connecting tracer to pipe, not me..I try not to hurt my hands, ill just stab you in the heart, much easier..
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I think I made a potato one, but that was back in grade school...
saline in the ground conducts electrical current and the proper way to protect buried steel lines is cathodic protection, hence why all the utilities are going to poly pipe..just eliminate the problem all together..
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Yes, saline and many other minerals along with water will create a solution that can carry electrons and worsen corrosion. Regardless of there being a galvanic potential or not you can still have electrolytic corrosion. I specifically noted that the exposed cut threads on galvanized pipe(which is coated with zinc for cathodic protection) will be the most susceptible to corrosion.
And even if the threads aren't touched until all of the zinc coating is gone we all know that the thin layer of zinc is worthless which is why galv is garbage.
Now if you have a scenario where a steel gas line runs from a tank, underground, into a regulator, and then to an appliance with all metal pipe and fittings being used along the way it will be grounded at the appliance. If that appliance has any sort of electrical issue that isn't serious enough to trip the breaker than both the neutral and the ground hooked to the gas line will carry current in relation to their resistance.
Because though some say "Electricity takes the path of least resistance" this isn't totally true. Electricity takes all of the paths, the ones with least resistance see more current. Just like hooking two headlights off the same positive terminal on a battery. They can be hooked in parralell and still both conduct electricity.
Now that we've determined that our steel pipe is charged with a voltage potential(alternating or direct, both will do), we can look at how it will suffer from electrolytic corrosion and galvanic corrosion. There are different ways to deal with each. We'll start with the galvanic corrosion, our pickle.
The pipe is charged like the steel nail in our pickle. The pickle also has a copper nail or bare wire inserted, but this can be replaced with any metal which is dissimilar from our steel pipe. It can even be another steel pipe or the metals in the dirt. As long as they aren't at the same galvanic potential one will be the anode and one will be the cathode. As you pointed out steel is usually the cathode because of it's place on the galvanic chart so often our anode will be a nearby copper gutter or grounding rod. The cathode will be consumed while the anode may gain material, this is how electroplating works, that is electrolytic corrosion caused by a galvanic potential.
Now we can talk about the electrolytic corrosion aspect. Galvanic corrosion comes from the metals themselves producing a charge. Electrolytic corrosion comes from a charge being placed on two metals with an electrolytic solution(wet dirt) between them. If the steel pipe has a potential, and the copper grounding rod(or any other anode) also has a potential than we will get electrolytic corrosion happening. If we use the tracer wire to connect them and make them the same potential(mostly) than we can limit the electrolytic corrosion.
As you can see galvanic and electrolytic corrosion are closely linked but are not the same.
There's your 1st year apprentice explanation.
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The short answer is that the pipe is one electrode and something else in the earth will be the other electrode. While they will make a galvanic reaction and the pipe will likely suffer galvanic corrosion they both may also be at different voltage potentials and if we connect them with the tracer wire than we can stop that voltage potential and limit electrolytic corrosion.
If it makes you feel better I used to prototype electrical devices.
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you mean they gave you shock treatment at the mental hospital....:vs_laugh::vs_laugh:
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Gotta change the subject? Can't even man up and admit when I have made a good point?
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I didnt even read that freaking book you posted..too late. maybe tomorrow..
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I know you have trouble reading.
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Wow. I’m not gonna go in to cathodic protection or anodic protection; it sounds like you guys have no lack of opinion on it.
Tracer wires aren’t required for metallic pipe (around here anyway). If you use PE with with stab fittings or use the fusion welded stuff you have to have a tracer (and in most circumstances, detectable burial tape).
Btw an older plumber told me that the burial tape worked with divining rods. So yeah. There’s that too. 😜
Tracer wires aren’t required for metallic pipe (around here anyway). If you use PE with with stab fittings or use the fusion welded stuff you have to have a tracer (and in most circumstances, detectable burial tape).
Btw an older plumber told me that the burial tape worked with divining rods. So yeah. There’s that too. 😜
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any buried line NEEDS caution tape about a foot above it....steel lines no tracer, poly pipe needs tracer line....the short and sweet of it..
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who? you have to quote who your asking the question to..
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Back in the late 70's I often ran sch 40 PVC gas pipe with a tracer wire
it was required to be a min. of 18" deep, :biggrin:
it was required to be a min. of 18" deep, :biggrin:
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