Welding refractory anchors

Date 01-08-2009 16:52

Is there a separate code (ASME sec. VIII / IX) requirement for developing procedures to weld refractory anchors (800H or 800HT) to the inside of a 516 Gr.70 vessel. If so where can I find the specifics. I've looked in sec IX and I think i can just develop a regular welding procedure but am not sure. The processes that could be used will more then likely be SMAW (Inconel 182 filler) or GMAW (Inconel 82). I am not sure of the other specifics such as the wall thickness of the vessel or size of the anchors. Any guidence would be greatly appreciated.

On a side note would it be possible to go to a 304 filler as a cheeper alternative. I have looked at several consumable manufacturing companys dissimilar joing charts and It doesn't seem to be recomended but I can't think of why. My only thought is that this alloy (800H) is used for high temp service and it is exspected to see those temperatures, where as these anchors will be burried under refractory and most of the anchor won't see crazy high temperatures at least not what 304 couldn't handle.

Thanks again for any help,

Charles

By 803056

Date 01-08-2009 21:00

You can use the WRC diagram or better yet, the modified WRC diagram by Kotecki and Lippold, to estimate the ferrite number of the diluted weld.

I would be suspect of using 304 filler metal when welding to the carbon steel. There is a good chance your ferrite number would be too low and cracking can be expected due to LMPC.

Best regards - Al

By ravi theCobra (**)

Date 01-09-2009 18:02

Basicly you have to weld with the appropriate rod and preheat in the range of 200 - 225 ' F.

Where I worked once we had to do this and it was a bear -

Watch out particularly if the inlet / outlet gas chambers being lined are subject to pressure - ours were 150 psi

and we had to do penetrant on them -

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

Date 01-12-2009 12:19

Back in my days of erector engineer I had to weld the refractory anchors of three crude oil furnce heaters. The heaters' shell was carbon steel and the anchors were made of high alloy steel. Many years have passed since then and I don't remember what kind of alloy steel was it.
The anchors were welded with stick electrodes of a composition compatible with that of the anchors, and were specified by the heaters manufactrurer. Again, I don't remember the electrodes type. Neither the WRC 1992 nor the De Long diagrams existed in those days.
Clearly, and Al agrees with it, a 304 type electrode is insufficient for that application. Remember that no chain is stronger than its weakest link, and it's useless to have an anchor that withstands the sun temperature welded with a material that will melt with boiling water. (I'm exaggerating, of course).
The cost of the welding consumables is little compared to the cost of the finished vessel, i.e., ready to be put in operation, so, in my opinion, welding consumbles is not the right place to save money.
Giovanni S. Crisi
Sao Paulo - Brazil

By Uncle Chuckles (*)

Date 01-12-2009 15:39

Thanks guys,

As a youngin in welding I have recently developed a understanding in the complexities involved with this industry. The more I learn the more it is evident that there is so much to know. This forum helps me time and time again make informed decisions. I really appreciate all the advice that you gentlemen provide. Thank you.

I will be staying away from 304 and other cheaper electrodes and go with the manufactures recommendation (Inconel 182 / Avesta P10). Has anyone worked with these filler metals, and can offer some advice on what to watch out for? Repairs would be quite costly on this vessel and time is not on our side to begin with.

Thanks again for all the help,

Charles

By Uncle Chuckles (*)

Date 01-12-2009 17:01

Just for my knowledge I used the DeLong diagram on a 308 filler and the weld metal would be pure austenite. You were absolutely right Al

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

Date 01-13-2009 19:21

The De Long diagram dates back to 1973 and it's already obsolete. You should use the WRC 1992 diagram, which was developed in 1992. If you don't have it, it's available on the Internet.
Regarding the fillers you mention, they're not so easy to use for who's accostumed to use carbon steel. Reason is the high chrome and nickel content.
If you don't have a welder who's familiar with those filler alloys, ask INCO and Avesta for their reccomendations, buy a few extra pounds of filler and have your welder practice with them, following strictly the reccomendations.
Giovanni S. Crisi

By Uncle Chuckles (*)

Date 01-13-2009 19:23

I will use the WRC 1992 diagram, thanks

Charles

By 803056

Date 01-14-2009 20:06

Use the WRC diagram that has been modified by Kotecki and Lippold. You can probably get a copy from the Lincoln web site. It is modified to permit joining of carbon steels to stainless steels and provides useful information about the expected microstructure of the HAZ as well as the weld deposit.

Best regards - Al

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

Date 01-16-2009 20:01

Al,
I've just searched the Lincoln website and found the usual WRC 1992 diagram published by Kotecki and Siewert on the May, 1992 issue of Welding Journal.
I found no references to the Kotecki ands Lippold diagram.
Giovanni S. Crisi

By Uncle Chuckles (*)

Date 01-16-2009 20:31

I found the diagram as well and I believe (Al will correct me if I'm wrong) Kotecki was the gentalman who added the Martinsite boundary to the WRC-1992. Search for AWS WRC-1992 in google (I don't know how to attach files on this fourm).

Hope that helps,

Charles

By 803056

Date 01-16-2009 21:41

I have a copy of the file, but it isn't compatible with this system and it gets corrupted when I tried to convert it to something compatible with the forum's system.

You are correct that this is the modified WRC that I find very useful when joining carbon steel or low alloy steels to stainless steels.

Best regards - Al

By bigjongpls (*)

Date 06-19-2009 06:13

When we weld anchors and clips in a cement plant preheat tower we use Avesta 309l-16. Been doing it for 9 years now with no failure.