welding on springsteel

Date 10-30-2002 00:05

Springsteel is a high carbon, heat treated steel which is impossible, or at least very difficult, to weld. Even if you could weld it, the heat generated by the weld would normalize the welded and heat affected zones and the springing properties would disappear.
Giovanni S. Crisi
Sao Paulo - Brazil

By dee

Date 10-30-2002 08:31

GS,
Does thios mean it should be normalized, then welded, then re-tempered again, calling for both pre and post heat treatments?
d

By G.S.Crisi (****)

Date 10-30-2002 14:15

No, it means that a spring can not be welded.
First of all, high carbon steel is extremely difficult, if not impossible, to weld.
Second, even supposing that you'll be able to weld it, a weld within the spring is a discontinuity. Even if you do as you suggest, the spring won't behave as it was supposed to when it was made.
Giovanni s. Crisi

By Jay Krout (*)

Date 10-30-2002 18:38

We were in a jam with some broken springs on a 75ton truck in the mines, I looked for the right springs in the graveyards but none were to be found, so I ordered new ones. Meanwhile, to keep the truck running, I beveled them and preheated them after I had them set to the right arch or bow or whatever you want to call it and stick welded them with stainless( don't remember the number,sorry) and put them on the stove in the breaker to cool them down slow(it was wintertime) and put them back into the truck the next morning(in a snowstorm:( not happy). They held together for 4 months, and then I put the new ones in. I guess that as long as the main lower springs aren't broke it's a suitable temporary fix. I don't know what he wants to fix but that worked for me. By the way the new ones got there the day after the truck was running. What a way to make a living. Just a thought hope this helps some one. J Krout

By dee

Date 10-31-2002 17:13

GS
As many of us are in the repair business perhaps a man of your technical cunning might help devise a means to control the stresses.

It has also been published that automotive frames cannot be welded, nevertheless, techniques exist which are in regular use. One might consider adapting a similar technique; a suitable collar, or splint if you will, to redirect the stress... perhaps even secured by means of a capilary process selected to not interfere with the heat treatments (if any exist).
I would suspect a piece of similar spring suitably cut, ground and fashioned to serve as filler, and select a suitable GTAW torch as my heat source, as being the right stuff to use, however I lack the necessary metallurgical knowlege; its beyond my level of experience and I can only hope a suitable structure would develop in the HAZ that could be corrected by later treatments.

I do recognize the kernel of practicality from which your description of the problem as being irreparible stems. There are facilities that are equipped to fabricate new springs, and indeed it likely is a valid and more practical conclusion to pursue that alternative wherever possible.

I continue to hold your opinion in high regard, and bow to your experience and discretion.

Regards,
d

By billvanderhoof (****)

Date 11-02-2002 07:41

One problem with repairing springs is that they have almost always failed from fatigue. Hence the surrounding materials grain structure has gone in an unfavorable direction and there are probably tiny cracks all over the place. Were this not the case (i.e. new material broken by overload) all springs I have seen were made of material that had been rolled or drawn to shape. This modifies the grain structure in a favorable way that I doubt can be duplicated in a weld. Heat treatment after welding would not be a problem to one who had the appropriate oven and knew what sort of alloy he was dealing with.

All in all difficult to do, results are poor, and new parts aren't usually all that expensive.

I have heard that blacksmiths of exceptional skill can forge weld this stuff and get a reasonably good result. Forging retains the grain structure and no filler is used. I have also heard that blacksmiths of any less than exceptional skill can't even stick the stuff together.

If you just want to use old spring as wear strips on a backhoe bucket (it's good for that) 7018 will put it on just fine.

Bill

By dee

Date 11-02-2002 20:00

Bill,
Thanks for the depth. It helped, but (as a favor, for the future) don't be afraid to use the proper technical terms- I can look up terms I do not fully understand; it points me in the right direction.

I liked the message better when I ended it after I said "Thanks, it helped [me]"... I appreciate your effort and benefit from the knowlege you impart to me/us.

regards
d