Talk:Exothermic welding

Trademark issue
I have left a similar message on the talk page of. All I could find on the issue of the trademark is that CADWELD is a trademarked brand name of a line of products manufactured by ERICO (including here); nothing I have found says that the CADWELDing process is a trademark of ERICO. If someone can provide a U.S. patent number or other, similar reliable information that shows that the CADWELDing process is or was a trademark of ERICO, please provide it so we can incorporate appropriately. Otherwise, the current version, which was largely a revert to this version dated 22 March 2009, is worded just fine, i.e., from NPOV and without blatant advertising tone. KuyaBriBri Talk 15:29, 16 April 2009 (UTC)


 * I'm no expert on the subject, and can't remember why I edited the page in the first place, but I will give an opinion.


 * Firstly, I don't like using the name "exothermic welding" for the article. Cadwelding seems to refer only to exothermic welding used to produce an electrical connection.  There is another article - thermite welding - describing the use of other exothermic reactions to produce a mechanical bond between two metals.  The name "exothermic welding" would cover both areas, and the articles would need to be merged.  I'm open to merging them, but if they are separate, this name should not be used.


 * The version of the article submitted by ERICOLEGAL seems to be a clear advertising page, and if not removed should at least be moved to a page describing only the brand (see kleenex and facial tissue for an example) and heavily edited to make it neutral. In other articles involving trademarks, the trademark symbol is not used for every instance of the trademark - this request seems rather pointless, especially as CADWELD seems to be somewhat genericized.


 * I also think that the CADWELD material safety data sheets should be considered valid sources for an example composition used for exothermic welding. The rationale for using independent sources is primarily to avoid biased information.  However, I'm pretty sure it would be a violation of federal law for ERICO to lie about the composition of their product on the MSDS, so the information here should be reliable.  Similarly, the information on the history of the process should be added back, if it can be verified that Cadwell invented or popularized the process.


 * --Pyrochem (talk) 01:26, 19 April 2009 (UTC)


 * The problem with referring to the process generally as "cadwelding" is that it is a misuse of the trademark CADWELD. ERICO's effort here is akin to Xerox's campaign to keep people from using XEROX as a verb referring to photocopying, as in "xeroxed" or "xeroxing" (see Xerox).  I can recall Xerox running television ads in the 60s just to address this issue.  As such I can understand ERICO's point in wanting to prevent misuse of its trademark, which over time could weaken its trademark rights.  (Pyrochem's reference to CADWELD as "somewhat genericized" illustrates the threat perfectly.) Froggy88 (talk) 20:37, 13 May 2009 (UTC)

detailed quote, please
I'd like to see the paragraph and surrounding text in context for the printed source given for the sentence. "Such welds are commonly known as Cad-Welds and Cadwelds, and the process as Cadwelding." This would seem to give excessive prominence to one of the companies. DGG (talk) 20:30, 17 April 2009 (UTC)

Trademarks (again)
Wizard191 recently removed references to brand names used for this process by several companies (Cadweld, Thermoweld, and Ultraweld), calling them "spam." I strongly disagree with this position. I think a reference to brand names, if done neutrally, would benefit the article. To go further, all of these brand names ought to redirect here. ("Cadweld" and "Cadwelding" already do.) "Mylar" redirects to PET film (biaxially oriented), which lists other brand names. More brands are listed at Polyethylene terephthalate. As long as the list of brand names is made without favoritism, I don't see the problem. Anyone else have a view on this? - Froggy88 (talk) 19:28, 4 March 2010 (UTC)


 * I'm no expert on this topic, but I removed it because it seemed spammy to me. Mylar is a very common brand name that is used to refer to PET, so that makes sense, however for the above brand names to be restored I would like to see references supporting their common use. For a good example of this see heli-coil. Wizard191 (talk) 21:29, 4 March 2010 (UTC)


 * From a quick search over at Google Books I came up with this from Crisp, John, Introduction to Copper Cabling, 2002, ISBN 0750655550, at pp. 87-88: "Exothermic Bonding. This can be used weld cable to cable and for cable to ground rod to provide system bonding.  Many cables are, of course, copper but this method can be used to weld a range of metals such as stainless steel, cast iron, common steel, brass, bronze and Monel.  The method is marketed under a variety of names such as Cadweld, Techweld and Thermoweld."  Froggy88 (talk) 22:19, 4 March 2010 (UTC)


 * Awesome! Please add that ref into the article. Wizard191 (talk) 23:09, 4 March 2010 (UTC)


 * Favoritism continues to be an issue with regard to brand names. Removal of all brand names is the only logical solution. smarcomb (talk)(UTC)Smarcomb (talk) 11:55, 27 July 2010 (UTC)


 * Reliable sources that state commonly used trade names are perfectly acceptable. Wizard191 (talk) 12:51, 27 July 2010 (UTC)

Proposed merge from thermite welding
It seems that the two articles are describing the same process, with the thermite welding article having a rail used slant. If they are really the same process (of which I'm not sure because I know nothing about the process), then they should be merged. Wizard191 (talk) 22:36, 2 June 2010 (UTC)

Exothermic reaction <-> Exothermic welding <-> Thermite welding <-> Aluminothermic reaction
All the three seperate listings in Wikipedia have mixing content and do not clearly point to the correct definition:
 * Exothermic reaction: simply said a reaction (oxidation & reduction of material) that produces (extensive) heat
 * Exothermic welding: a process "welding" two parts together using the exothermic reaction. This reaction is producing a super hot molten material (not copper, not iron - just material in general) creating a molecular bonding of the parts. Such exothermic welding process always require a closure/covering material (mold) around a limited area of reaction. Common are ceramic or graphite molds which can resist the extremely high temperatures. The shape of the mold is defining the design of the molecular bonded connection. Most common connections are steel to steel (a.k.a. thermite), copper to steel, copper to copper, aluminum to copper or aluminum to aluminum.
 * Thermite welding: using the trade name "Thermite" which is a composition of (iron) oxide powder and aluminum powder. As aluminum is used to reduce the other material, this exothermic reaction is called aluminothermic reaction or aluminothermic welding. —Preceding unsigned comment added by Wassernase (talk • contribs) 13:59, 16 July 2010 (UTC)


 * So what's your point? You support the merge? Wizard191 (talk) 14:40, 16 July 2010 (UTC)

I support the merge to the generic process name exothermic welding. The brand names (as I understand it both Thermite and CadWeld are brand names) can be mentioned along with any other available supplier. Ke4juhjim (talk) 20:38, 1 April 2011 (UTC)

Railway application
why is termite reaction used on railway tracks?? —Preceding unsigned comment added by 84.68.142.165 (talk • contribs)
 * I'm not absoloutely sure but I think it is because it provides a conviniant portable way to produce enough molten iron to fill the gap between two rails. Afaict most types of welding done only produce a narrow seam of weld not a complete filling of a gap between two peices of metal joined end to end.


 * As for why railways are welded rather than bolted that is because it allows a much smoother joint. Plugwash 01:30, 3 November 2007 (UTC)

I thought the gaps between the rails were to allow the tracks to expand and contract with temperature changes... so the rails don't buckle in the heat. Steel expands and contracts a fair amount with temperature changes. Is there a better page for my question? --PReinie (talk) 17:41, 13 April 2009 (UTC)


 * This is true; traditional track with short rail lengths allowed the rails to expand easily. Obivously long lengths of welded rail don't have these small regular gaps. So, welded track will have special expansion joints (know as breathers sometimes in the UK) which allows the rails to move as temperature rises. Also to combat the effects thermal expansion rail is 'stressed' - have a look at the Rail stressing page for a full description. This is all part of my day job! Hope that helps :-) Zozzie 9t9 (talk) 14:51, 30 July 2009 (UTC)

some thermite answers
Greetings, all. This is my first venture into Wikipedia as a potential contributor. I was a trackworker in the USA for 32 years, and my specialty was track welding, including thermite. I want to make some corrections on the thermite page, regarding some materials. The item in question was the mold. For rail welding, a sand mold is used. Depending upon the manufacturer, the mold will be in two or three parts, plus a diverter plug in the pouring gate. The sand mold is formed and hardened by the manufacturer and installed by the welder. When a thermite process is used for signals - the bonding of wires to the rails, a graphite mold is used, which is reusable many times. A steel weld reaches a much higher temperature than a copper one, and a graphite mold would be consumed by the high temperatures. In signal bonding, the mass of molten metal is quite small, and the mold is lightly clamped to the side of the rail, also holding a signal wire in place. In rail welding, the weld charge can weigh about 30 pounds, 12 or 13 kilograms. The mold is bulky and must be securely clamped in a very specific position and then subjected to intense heat for several minutes before firing the charge.

When rail is welded into long strings, the longitudinal expansion and contraction of steel must be taken into account. As has been mentioned here, British practice (and very likely many others) is to use a sliding joint of some sort, to allow this movement. American practice is very often straightforward restraint of the rail. The rail is prestressed, or conssidered "stress neutral" at some particular ambient temperature. In my locality, that was 75 degrees F. or about 24 degrees C. The rail is physically secured to the ties (or sleepers) with rail anchors, or anti-creepers. If the track ballast is good and clean and the ties are in good condition, and the track geometry is good, then the welded rail will withstand ambient temperature swings normal to the region. In my case from -50 degrees F. to about 100 degrees F. (about -45 C. to 37C.)

The one inch gap between rail ends for welding (25mm) is to allow consistent results in the pouring of the molten steel into the weld mold. In the event of a welding failure, the rail ends can be cropped to a 3 inch gap (75mm), removing the melted and damaged rail ends, and a new weld attempted.

In ordinary jointed rail, it is standard practice to leave a small gap between the rail ends inside the bolted joint, to allow for thermal expansion and contraction of the rails. About a fourth of an inch (about 6mm) is normal in my area, especially if the rails are placed in the winter.

Now, if I've done this right, all this verbiage should appear on a discussion page, for your remarks. Thanks. JPGandyman (talk) 04:50, 13 May 2011 (UTC)


 * Hi JPGandyman, your recommended addition sounds good to me. Feel free to add them to the article. If you have any secondary sources to add to reference your additions that would be even better. Wizard191 (talk) 14:27, 13 May 2011 (UTC)


 * to Wizard191, I'm reading assorted help notes and style pages, and still feel like I am poking around in a dark cave with a sharp stick. I tend to go wherever I find a path. Am hoping to avoid sudden pitfalls. In your reference to secondary sources, may I post a web page link to a manufacturer of rail welding kits? Maybe also some language like this: "This writer has performed thermite rail welds for more than twenty-five years, using Railtech Boutet™ materials." JPGandyman (talk) 20:11, 13 May 2011 (UTC)


 * Ehh, using manufacturers' websites for references are usually frowned upon. It depends how much the particular page is trying to sell something or how informative it is. Also, don't refer to yourself when writing the text. Actually the tone you used in your initial post is pretty good. Wizard191 (talk) 21:15, 13 May 2011 (UTC)


 * to Wizard191, Thanks for your feedback and guidance. I will compose something and post in the sandbox, if that is the appropriate method, before making it real. Am afraid I do not speak or write British English very well, being conversant only in middle American dialect. JPGandyman (talk) 21:38, 13 May 2011 (UTC)
 * Yeah, feel free to make the modifications in your sandbox and then let us know when you are done with your modifications and someone here will take a look at it (probably me, because this page isn't watched by many). As for British English note, that's just for spelling purposes (i.e. behaviour vs. behavior, color vs. colour, specialize vs. specialise, etc.) not the dialect or tone. Don't worry about that too much; again it will get cleaned up by the nature of Wikipedia. Wizard191 (talk) 22:23, 13 May 2011 (UTC)

to Wizard191, thank you for your reply, and thank you for shepherding me through this project. I will let you know when there is something to look at. JPGandyman (talk) 04:58, 14 May 2011 (UTC)

to Wizard191, I believe I have placed some text on a user page under my name. It is not formatted yet. Got to insert appropriate tags to reproduce the appearance of the original page. JPGandyman (talk) 04:00, 16 May 2011 (UTC)


 * Looks good! I added your changes to the main page. Feel free to make more changes as you see fit. Wizard191 (talk) 22:26, 17 May 2011 (UTC)

Thank you for your help, and thank you for adding the changes to the main page. Saved me much sturm und drang, figuring out the markup codes and general formatting of the page, then finding the correct path. (I can hide my own easter eggs.)Thanks much. JPGandyman (talk) 02:51, 18 May 2011 (UTC)

New Images
Hi, I added some images that I believe are relevant, but I know very little about the subject and hope I have added them in the right place Iain (talk) 04:18, 6 July 2011 (UTC)

Coherence?
The introductory paragraph refers to only copper exothermic welding (for electrical conductors) but then in the overview only iron based exothermic welding is discussed. So the article as a whole is not particulalrly coherent. Looks like the introductory para has been patched in from a description of copper exo welding. As previously suggested by others this article would benefit from possible merge with others and introduction of some structure: Generic topic - exothermic welding -> specific examples - copper conductor welding, rail welding, others (together with mention of the relevant trade-names if appropriate.81.106.218.66 (talk) 11:57, 18 April 2012 (UTC)


 * Yeah I noticed the same problem. It's probably a remnant from merges with insufficient cleanup. I'm not sure it needs to be split up, but at least we should add other metal oxides. I've gone ahead and adapted a section from Thermite for that purpose. Sakkura (talk) 17:26, 22 May 2012 (UTC)

Error in link to sleeper
The link to sleeper in the second paragraph of the "Process" section points to "sleepers" the movie instead of "railroad tie". Not sure how to make this edit. — Preceding unsigned comment added by 192.139.122.10 (talk) 23:49, 10 March 2014 (UTC)

Link to commercial site?
I see a link was just added to escoltrix.com for one of the trademarked names of exothermic welding. I am asking other editors: is this appropriate? Why link to one of the dozen or so names? Why link to any in the body of the article, instead of perhaps a reference link?

Thanks. IAmNitpicking (talk) 14:47, 17 February 2017 (UTC)

Merge discussion
I propose that Thermic welding - which is a very short article - be merged into the much longer Exothermic welding. I'm not expert enough to carry out a straight WP:BOLD blank-and-redirect. -- Red rose64 &#x1f339; (talk) 18:00, 30 January 2020 (UTC)
 * Redirected, as there was indeed nothing unique from there to merge. Klbrain (talk) 21:19, 29 August 2020 (UTC)

Thermite/Thermit
It says "thermite welding" is also known as "thermit welding". Is this actually true in English-language sources? Or is it a simpler case, that it's precisely the same term (i.e. not "also known as"), and just happens to be spelled differently in different languages? TooManyFingers (talk) 06:25, 23 August 2021 (UTC)


 * For example, it would be very unusual to write "Bread is also known as Brot" - because in English contexts it actually isn't (other than in special cases that don't seem relevant here). TooManyFingers (talk) 06:32, 23 August 2021 (UTC)