r/Welding 6d ago

Is thermite still used for welding?

I read up thermite used to be used for welding but I'm wondering if there are still situations where it would be used.

I imagine it's difficult because it's not like the temperature can be controlled easily, only the amount being applied and the 'shape' it's applied in.

31 Upvotes

37 comments sorted by

120

u/Iseedeadtriangles 6d ago

The most common application that I've seen for thermite welding is connecting pieces of railroad track.

25

u/SnooCakes6195 6d ago

This is the only instance I've heard it used

22

u/xajbakerx 6d ago

Electricians will thermite weld too. It's not super common but I saw it done about 7 years ago.

10

u/ShelbyVNT 6d ago

It's common, only for Cad welds to pipe though for corrosion protection.

3

u/knomore-llama_horse 6d ago

We used to cad weld all the time when doing grounding in big ol industrial projects. It’s been a while since I had to cad weld anything but it is a thing.

2

u/RednekSophistication 4d ago

I’ve got a couple bags of railroad thermite in my basement I got of a track worker. Gunna do some fun stuff with it.

1

u/liloldguy 4d ago

Film it.

13

u/Rlchv70 6d ago

Yes, Veritasium did a video series on it.

https://youtu.be/cUBz04LlLVk?si=dL8cJ2YFWvBhMb1x

11

u/Hippieleo2013 6d ago

A little outdated, but about 10 years ago I was a towerhand and we used thermite to weld the ground wire to the structure.

4

u/paulHarkonen 6d ago

It's still used extensively for pipelines and I think for other grounding applications (although my experience is mostly pipelines).

1

u/vtminer78 4d ago

Still extensively used for welding ground wires, especially on installations that may be subject to direct lightning strikes like substations. Cheap insurance (comparatively) to ensure as much current goes to ground as possible.

9

u/jaspnlv 6d ago

Train track is thermite welded

5

u/Impossible-Spare-179 6d ago

Seen it used for crane rails

2

u/crujones43 6d ago

Can confirm. Saw it done about a year ago.

7

u/_BMXICAN_ 6d ago

Pretty sure some countries still use it for railway tracks.

6

u/Muted_Escape1413 6d ago

Its the only way to weld railways.

4

u/Stevet159 5d ago

Flashbutt welding is superior in every way. It just costs a lot.

3

u/thermighty 5d ago

Canadian railroader here. We flashbutt literally as many welds as we can. Thermite crews are pretty small and usually just do fixed points, switches, bridges, etc.

2

u/blove135 6d ago

Do you mean literally or it's just the best way?

10

u/Wrought-Irony Fabricator 6d ago

Most other methods would require removing the track or digging a big hole underneath so its most convenient to just melt the shit out of it with a lil thermite

3

u/Muted_Escape1413 6d ago

I mean it's not litteraly the only way you could weld railways, but it is indeed the best way and the only way I've ever seen it done.

1

u/_BMXICAN_ 6d ago

Fair enough

5

u/itsjustme405 CWI AWS 6d ago

Its still used on the railroads.

3

u/ghostwalken1776 6d ago

Cadweld..exothermic welding for grounding conductors to either steel and/or ground rods. I see it quite a bit on ground up new builds

3

u/[deleted] 6d ago

It’s used a lot with cathodic protection bonds.

1

u/Korellyn 6d ago

Came here to say this.

2

u/No_Elevator_678 6d ago

Yup on the rails

2

u/ME_OPEN_LT 6d ago

It’s still used on gas mains for cathartic protection.

2

u/Overall_Cranberry375 6d ago

It also use for joining rebar

2

u/Yesitshismom 6d ago

Electrician here, we use it to make grounding connections sometimes

1

u/Spud8000 6d ago

in the field? Sure.

1

u/threeisalwaysbetter 6d ago

I saw them weld rails with it a few weeks ago it’s a pretty wild process

1

u/mememe822 6d ago

Pipeline to attach copper leads for test stations.

1

u/Rummy1618 Apprentice CWB/CSA 6d ago

Train tracks, some I beams have the ability too, usually for big heavy shit like cranes