need some input

Date 12-02-2005 12:59

Many years ago I authored an article on "Chemical Engineering" magazine on abrasion resisting material for grinding mills.
You don't know the chemical composition of your ring, and you'll never know it, because it's a confidential information that makes part of the manufacturer's know how and is not disclosed to the public.
However, the chemical composition is just one part of the know how. The other are the thermal treatments that the piece has undergone to achieve a uniform hardness of, may be, 50 HRC (Rockwell C) or more. "Uniform hardness" means that it's the hardness of all of the mass of the material, and not just that of the surface. Consequently, your ring's microstructure is a highly martensitic one.
At this point, you've already understood that making welds on that material isn't an easy task.
Unless someone in this Forum has an actual experience on how to weld Remco 9000 crusher's rings and is able to give you a valuable information, I suggest you to get in touch with the equipment manufacturer and ask for his reccomendations. Of course, first thing he'll try to do is to sell you a new ring, but you can always convince him that in this particular moment you can't buy one because you're in a hurry and can't stop production, or because you're short of money etc.
A word of warning. Whoever in this Forum gives you a suggestion, he should have experience on Remco 9000 material. As I said before, the material chemical composition and thermal treatment make part of the manufacturer's know how, and therefore may vary from one to the other.
Not only that, but they will vary also within the same manufacturer, depending on the material to be crushed (hard and abrasive vs. soft and smooth) and/or the money you're willing to spend. A material containing 5% of chrome, for example, is better than one containing 2,5%, but is also more expensive.
As a conclusion, there are several abrasive resistant materials for grinding applications, and that's why I suggest you to listen to the
manufacturer's recommendation.
Giovanni S. Crisi
Sao Paulo - Brazil

By weldo

Date 12-03-2005 02:37

Thanks for the suggestion, and the info. G.S., the first suggestion that I referred to in my original post, came from a welding supply distributor, I was, and still am quite skeptical about that suggestion, which is why I posted here, anyway, I will try to contact the manufacturing co. and see where that leads. Yes, I was aware of the material being consistent throughout, which is why I definitely want to find the proper procedure for this application, I do thank you for all of your input on this, and still hold out hope that someone else here may possess the info. I am looking for.

Steve

By pipehead (***)

Date 12-03-2005 08:15

Just Another suggestion if you can't get anything out of the manufactuer you Might try contacting the Stoody Company they are manufactuers of hard facing and build up rods for this purpose. We used them a few years ago on a Cedar Rapids Crusher and they sent out one of their engineers to take a look at what we needed to accomplish and also explained the procedure to us very well.

Hope this helps.

By weldo

Date 12-04-2005 05:20

Appreciate the advice, we use the stoody XHC quite a bit on some of the parts, i have even wondered if the super 20 would work for the build up portion of this application, due to the fact that it contains Chromium, molybdenum, and tungsten, but it is limited to single pass application only, due to it's tendency for checking, the idea of contacting them is a good one and I will certainly look into it.
Thanks.
Steve

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

Date 12-05-2005 15:57

Looks like you're on the right way, Steve. I'm anxious to learn how this project ends up. Please tell us, frequentors of this Forum, how you managed to solve your problem.
Givoanni S. Crisi

By lewis edwards (*)

Date 12-06-2005 00:24

I had a different situation but we had to replace a wear deck on some coal mine equipment the new piece was made out of Hardox 400 material . One of the applications for this material is crushers . For thi material they recamend under matching the filler marerial and reducing the heatinput as muchas possible . We torch cut the worn deck out apoxamatly 4' x 15' then instaled the replacement deck by slipping it between the side rails which were 4' apart . well we needed to have forgiveness on the sides so that we could slide this 1" thick pre-bent plate into place .With the literature we got from Oxelosund ( www.oxelosund.ssab.se ) and the input from our engineers we were told to weld it in with L-56 solid wire at the lowest voltage we could . We had .035 with 75-25 gas 23 volts was what we used. They also said no preheat and weld one side complete first then weld the opposing side after the plate cooled . It worked first time . Well it made it out of the shop anyway. We never seen the job again so I guess it worked good enough . It was our equipment .They said that any part subject to ware should only have the last to passes welded with hard surfacing . The hardness was HBW 370-430 on the specs .

By weldo

Date 12-13-2005 00:25

A recent update on this, I contacted the Remco Co. and spoke with one of their onsite Engineers, First off, he did tell me that the penta-ring is actually a chrome-iron cast made up of 28% chromium, the next thing he said, they did not have a specific procedure for welding it, in fact from what he was telling me, he said they had not had any luck with welding one of them, from what he said, even when they preheated, the weld looked fine, but upon cooling, it would crack out right on the weld area, he did suggest that maybe if it were wrapped in a heat blanket and allowed to cool slow that possibly it may work.
As for me, I just can't give up that easily, I have a few old ones around and I believe that with the right combination, I don't know, maybe.
If anyone has any Ideas or has ever done anything along these lines, I'm definitely open for suggestions.
Thanks, Steve

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

Date 12-13-2005 20:17

OK, Steve. Now you know that the ring is made of 28% chrome white cast iron and Remco has given a very few, although useful, reccomendations to you. Apparently, they didn't say anything on the ring's hardness, but I would "guesstimate" something around 50 HRC (Rockwell C).
If I were you, I would investigate further both Lewis' and Pipehead's suggestions.
By the way, Lewis, what do you mean by "hardness HBW 370 - 430"? Brinell perhaps? I've always seen it represented by the intials BHN (Brinell Hardness Number).
Giovanni S. Crisi