Black Powder Welding!
 

Reading today where the water line being installed out here uses Black Powder Charges to ground Each 20 ' section of pipe to the other. The 137,000' of 30 and 24" pipe has "O" rings sealing each section, and a heavy copper wire is welded from section - to - section to provide Cathodic Protection. A jig holds the wire in position, a worker pours in a small Black Powder Charge, and the "explosion" produces the heat to weld the copper wire to the steel pipe. That's new one on me...and I thought Thermite Welding of Railroad Tracks was about as 'far out' as it gets.

Sounds like the person writing the article doesn't check the facts very well. That sounds like Cadweld to me. :rolleyes:

http://www.farwestcorrosion.com/fwst/cable/erico01.htm

Heard of black powder cutting. Or is that just blowin' up ****?

Hank

A .22 hitting a can of black powder is fairly impressive. :)

Black powder is so unstable that legal retailers in MI must store in it a locked safe...
I couildn't imagine using it 'cept for the flint & percussion locks.

Now, that sounds more like it! Just another example of the press and their depth of knowledge required before they publish an article.

I agree with Hotfoot- Mike W has the correct explanation.

I'm a cathodic protection technician. Yes it's cadwelding, not very common up here anymore but some companys still use it to bond isolated sections of pipe to get continuity to the protection circuit. ;)

One is the concept, the other is the result!!! :D

Black powder now days is used for fuses, fireworks, and as propellant for black powder pistols, rifles and canons. It is a low velocity explosive. High velocity explosives are used for their cutting and shattering effect. Black powder was replaced as generally used civilian explosive during early rail road tunneling by nitroglycerin. Which was replaced by safer TNT and that was replaced by cheaper dynamite. TNT is a high explosive and dynamite is a low explosive which has more of a pushing effect. Black powder is not practical for cutting steel or explosively welding. Now days 2 part liquid explosives are the most used. It is basically nitrogen fertilizer and fuel which is cheap and easily shipped as flammable non explosive before 2 parts are mixed.

I have explosively cut scuba bottles with wraps of det cord and thicker steel with flex linear shape charge. You can explosively weld with data sheet. They all use a high velocity explosive called PETN. Explosive cutting leaves a wide ragged kerf with lots of slag.

let's hope not, that would just make a really big explosion as opposed to a really big POOF!!!!

your facts are a bit off, dynamite is nitroglycerin absorbed into keiselghur(sp) and is a high explosive, i don't believe TNT was ever used commercially, just by the military.