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OT Copper content in large transformers

SBAER

Hot Rolled
Joined
Aug 21, 2006
Location
Kitchener, on canada
I bought some large transforms, 150KVA, 900lbs. I have never sold such large transformers, so I don't know if there is much of a market for these things. Does anyone have any idea what proportion of the the transformer's weight is copper? I have heard that the silicon steel is worth more than normal steel as scrap, is this correct?
 
I'm no expert, but I have been made to understand that some of the older transformers had PCB's in them. That is, if they're not the "dry type"

I now wait for someone who knows what they're talking about to straighten me out and expound on this. I'm just trying to keep you from opening a can of worms.

Richard
 
There are guys that come up from Mexico to look at our transformers and determine whether or not they are usable or can be rebuilt.

If you advertise a little online, you'll have plenty of traffic interested in these who are willing to pay several times scrap price.
 
I have a friend that is a scrapper. He gets transformers all the time. I know he spends the time ripping them apart for the copper, but i cannot see how he comes out ahead spending the man hours deconstructing those damned things. I think he just likes destroying stuff anyway so it doesnt matter, but i would imagine he's only making a couple bucks per hour if you do the math. Not worth it to me, but i wonder if theres any other meathods for dismantling them thats more efficient. Once apart, there are all those copper plates to seperate. What a pain in the ass.
I was toying with the idea of making a filtered burner for him to burn off wire for all the copper wire he strips too. Scrappers could probably use something like that, but i dont want the burn off poluting the air. I was thinking of making a blower fed water filtration type of incinerater. Can such a thing be made easily for those that like to get all this copper wire and transformers? Would the energy spent in fuel make it worth it?
 
Booster, if you could solve the insulated wire problem for the scrap industry with something like that, then it will be the last problem you will ever have to solve.

From then on, it's pina colada's on the beach in Maui...
 
Before you do anything dractic have them vetted for insulation strength compatibility with common voltages etc. If they are oil filled have an oil sample checked for PCB's. If they are PCB filled you will probably have to pay to dispose of them at anauthorized site.

If they are the dry type and you want to scrap them you'll get more money from the clean scrap than intact transformers. Separate the coppere wound fom the aluminum wound. Dismantle the transformers to the wound core. Ifind a place in the boonies. Build a hot fir twice the size of the transformers. When it burns down to a bed of coals toss on the cores and add more fuel. Cover with old batt house insulation to hold in the heat and filter the smoke. Come back in a week when the transformers are cool The cores shoudl de-laminate easilry with a little encouragement. The windings will probably have some fiberglass residues. Rub them off with a wire brush. If any aluminum melted gather up the nuggets and remelt.

If the transformers will fit into a 55 gallon drum that works better. Better have a forklift and a fire hose handy. Still want to get into the scrap business?
 
If they are the dry type and you want to scrap them you'll get more money from the clean scrap than intact transformers. Separate the coppere wound fom the aluminum wound. Dismantle the transformers to the wound core. Ifind a place in the boonies. Build a hot fir twice the size of the transformers. When it burns down to a bed of coals toss on the cores and add more fuel. Cover with old batt house insulation to hold in the heat and filter the smoke. Come back in a week when the transformers are cool The cores shoudl de-laminate easilry with a little encouragement. The windings will probably have some fiberglass residues. Rub them off with a wire brush. If any aluminum melted gather up the nuggets and remelt.

They are dry, but that sounds like a bit more work than I am interested in. I was quoted $0.20 a lb for the complete transformers. I guess I will have to hunt around for a local used electrical equipment dealer.
 
PCB oil is heavier then water (density ~2.2) mineral oils are lighter (density ~.8), pour a drop into a can of wter and see if it floats/sinks. Cost my company >£250,000 25 years ago to rid themselves of all the PCB filled stuff
Frank
 
no big deal to scrap

Make sure the winding is copper, there will be 25% or better copper, at 3.00 a lb there will be a good deal of monny there. Just strip off the sheet metal case and heat up the core with a weed burner ( I have to think you dont have any laws about this in canada, thay would lock me up here in montana for the smoke) the steel core should fall apart with the heat and all you have to do is burn the copper winding and sell the copper....Phil in Mt
 
= Ifind a place in the boonies. Build a hot fir twice the size of the transformers. When it burns down to a bed of coals toss on the cores and add more fuel. Cover with old batt house insulation to hold in the heat and filter the smoke. Come back in a week when the transformers are cool The cores shoudl de-laminate easilry with a little encouragement. The windings will probably have some fiberglass residues. Rub them off with a wire brush. If any aluminum melted gather up the nuggets and remelt.

I hate to point this out, but that is pretty much an old way of thinking these days. I dont want to point the finger directly at you and start off on some tirade about global warming, but thats just not a good way of thinking these days. We have 6 billion people on the planet, and this isn the old west anymore. I for one am a "depopulationist" and wouldnt take much notice if that sort of activity took place on a sparsly populated planet, but i have to be responsible for my ancestors/offsprings quality of life. I dont want to catch a trout in a stream and eat it only to find that i just ate a toxic pcb laden fish, when i thought i was out in the boonies away from people. I grew up in a city with 3 oil refinerys. Im familiar with polution and corruption. I've grown up around toxic waste and government coruption that swept the waste under the rug(local river) for a nice little bribe. I know what the baby boomers did to my land in the race for wealth. They die old and rich and leave me with tumors and unatural premature death and disease. I believe one should be able to drink from a local river and not worry about what poisons them. We are the stain of the industrial revolution and we need to start cleaning it up, because with this bio mass we are only going to live in each others filth and suffer the poison until something changes. Again, this is not directed at you, but your generation. My fathers way of thinking is just the same.
Who know's, you may come back to live here some day.
 
I don't know any good clean ways to de-insulate copper wire. I guess Booster would rather throw it away and open more copper mines. I do know that the guys who used to rebuild a lot of the industrial motors in Tucson used to use a muffler gun or heavier air hammer to cut the coils off flush with the field shoes then tap the rest of the wire out of the field length wise. Didn't see the punch they used to move the wire out, but it might have been another punch fitted to the muffler gun. I know that when they had the rewinding job figured out it didn't take long to strip the motor and start over...Joe
 
Why not use them as.. gulp... TRANSFORMERS

Those things are probably worth a LOT more as transformers, if they aren't too smashed up or rusted out. Call a used transformer supply house & see what they'll do for you.
You'd be AMAZED at what utility transformers sell for... even used ones!
 
Well said Booster!!

I have rarely seen such an irresponsible piece of writing as that post from Forrest.

This is supposed to be a forum for professional informed advice!

Charles.
 
ah, if he was being satirical, then i totaly missed that :), but i know people here that would do that and much worse. From meth labs to oil refinersy, lots of damage is done in the name of making a quick dirty buck.
 
I GOTTA start using smileys. Do they make animated smileys where one heavily nudges another to make sure he gets the point?

Actually that procedure was the way it was done when I was a kid in 1957 working for spending money with a bunch of old bums in a junkyard. It's not too different nowadays except the old motor stators and transformers are placed in an oven, heated to 900 degrees with gas or electricity and the gasses burnt off in an afterburner. Same principle as the bonfire but far more equipment and cerfification intensive.

By the way the varnishes, organic insulation, etc that are burned away are contemporary plant products in the global carbon cycle. Once oxidized, its carbon dioxide is greenhouse neutral. Only the fuel gas (or the fueled electrical generating equipment) make a fossile carbon contribution. A clean dry wood fire is also greenhouse neutral. A wood fire once established doesn't make much smoke but when adding wood or inferior fuel the combustion products degrade accordingly. The burn-out oven produces far less objectionable gas but there is no evading a trace of that burnt toat reek.
 








 
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