Not Alloy 20 Now Hastealloy

Date 09-19-2010 23:05 Edited 09-19-2010 23:08

Off the top of my head, ER320 filler rod, stringer beads only, 350 F max interpass, 35,000 J/in. max heat input. If you overheat it, it will shatter like glass on a bend test. I believe Allegheny-Ludlum has a good Blue Sheet that includes welding info. http://www.alleghenyludlum.com

Edit: http://www.alleghenyludlum.com/ludlum/Documents/al20%20%28053106%29.pdf

By Superflux (****)

Date 09-20-2010 02:48

Some 347 would be cheaper to practice on. Carpenter 20 is high $$$ stuff. We had some 20 on a project last winter and yes ER320 is a filler match. When you get into production, be careful, that alloy 20 is some creeping, crawling out of alignment crazy stuff. Heat warp is outa this world! Use strong backs or other fixtures to control the warp. There will be warpage.

By js55

Date 09-20-2010 12:33

Most welders seem to think that Alloy 20 welds more like stainless steel (even though it is P45 the fillers are spec'd as SS's), though this is hardly a consensus because of the high Ni. Because of the Cu and Cb the heat needs to be controlled a little tighter than SS's (more like 310 maybe)(the Cu can contribute to hot cracking-though the newer low residual fillers don't hot crack as readily-and the Cb will segregate readily). Its chemistry is actually quite close to Alloy 800. Both of them are sorta bastard alloys and sit on the fence between nickels and SS's.
If you 've welded nickels and SS's you should have no trouble with Alloy 20.

By JeremyW83 (***)

Date 09-21-2010 01:59

I am also looking for any suggestions on the following:

I was reading online and it said that the interpass temperature limit was 300*. Is this accurate for all wall thicknesses? Also in the past I have gone about an inch to either side of the weld joint to check the temperature will this work?

What amperage ranges are the best for root to cap?

At this company we like to use nitrogen to purge the pipe but this has always been with 304L & 316L. Is this acceptable for Alloy 20 or do I need to insist using all Argon?

I have never welded Nickles and would be interested in how it is welded and how it could help me with alloy 20?

Are there any special tapes that I need to use cause they usually buy blue painters tape?

By Lawrence (*****)

Date 09-21-2010 03:48

Those are pretty high level questions Jeremy.

Is this company you are working for providing a Welding Procedure Specification?

Or are you about to qualify a procedure yourself?

Is there a specific code or specification you will be required to comply with?

By JeremyW83 (***)

Date 09-22-2010 02:59

Lawerence,

I believe there is already some WPS with the company but I have yet to see it. I am also going to call the prefab boss and see about getting a copy of these emailed to me so that I can review them. I will also be asking about any specific codes that we will be going by. The boss is not completely forth coming with information but I think this is because he does not know that much about welding this material. There is only one other person at this company that even knows how to weld this stuff. I am hoping to be able to talk to him about this in further datail but it might be difficult with him not wanting to come down to my job site.

By js55

Date 09-21-2010 10:25

Since the interpass is intended to control hot cracking testing the temp right in the weld is acceptable. The HAZ is not a problem, other than Cb segregation, though Cb is there predominantly as a stabilizer not as a corrosion resistant element.
Also, I would stay with argon. Alloy 20 has Cb in it. Nitrogen will form Cb nitrides that theroetically can cause microfissuring. I say theoretically since I have welded tons and tons of AL6XN (alloyed with N) with NiCrMo-3 (it used to be the filler of choice for that alloy)that also has Cb and have never experienced the microfissuring spoken of, though there has been research demonstrating such, though no where near a scale of damage to the part. I'd stick with Argon.
As for amp ranges, if you've welded 310 the parameters should be close enough. The concern is the same. Hot cracking.
Marty provided a link. There should be plenty more specific info available there.

By JeremyW83 (***)

Date 09-30-2010 01:12

Well found out that we do not have either a written procedure or a wps for Alloy 20. The boss I talked to said he was going to get on it because we are going to be having a lot of this piping coming up. But I check back in and update yall.

By JeremyW83 (***)

Date 10-02-2010 00:41

Now I have found out that it is Hastealloy that I am going to be learning to weld. I got it mixed up some how when talking to the senior welder at my company. That explains why we dont have a procedure for it in our code books.

So maybe I can restart this discussion but get some information on Hastealloy?

By Lawrence (*****)

Date 10-02-2010 00:53

Jeremy

Hastelloy is actually a family of alloys..

You can do a forum search with the term "hastelloy" and find about a million links that Henry has dropped at one time or another.

But until you share which hastelloy alloy your working with, there really isn't anything specific anybody can tell you about how it welds.

By JeremyW83 (***)

Date 10-02-2010 00:56

Thanks Larry,

I am going to be at the shop and will get more details tomorrow.

Sorry for all of the confusion.

By MBSims

Date 10-02-2010 01:51

Once you find out which alloy, you should be able to find the appropriate welding info here:

http://www.haynesintl.com/weldinginformation.htm

By JeremyW83 (***)

Date 11-13-2010 01:30

Well, the plant decided to go another route and brought in another contractor to do the welding. I did find out that it was C-276. The other company that got the job was also the ones the did the machining and inspecting of the tank. Also after my trial of welding with C-276 yesterday I am not ashamed to say that that was probably the best decision for the plant to make.

I have some pic that I am going to try and post.

Attachment: Hastelloy1.jpg (94k)

Attachment: Hastelloy2.jpg (215k)

Attachment: Hastelloy3.jpg (135k)

Attachment: Hastelloy5.jpg (180k)

Attachment: Hastelloy8.jpg (125k)

By swephnsyimf (*)

Date 01-12-2011 23:10

Based on the info that was obtained courtesy of or from the American Society of Mechanical Engineer (ASME) (i.e. one of their welding articles that was for the welding of the Alloy 20-Cb-3), they have provided their recommended guidelines with respect to welding of this type of stainless steel alloy (that is pretty close to and resembling the "Alloy 20" type of stainless steel) where the SMAW process is use, as follows: "(1) Use of the welding filler material type that was developed for welding of this material (i.e. types E320LR and ER320LR of AWS A5.4 and AWS A5.9, respectively), (2) Keep the heat input to an absolute minimum (i.e. recommended welding currents for the SMAW process should be only 80% of that typically employed for carbon steels), (3) Maintain a short arc length (i.e. this also will result in reducing heat input to the weld), (4) Maintain an interpass temperature of less than 200 degrees F, (5) In order to avoid crater cracks, filling of the crater at termination of welding and washing back across previously deposited weld metal and (6) Where possible, keep the maintain the base metal restraint to a minimum. For welding for which the GTAW process is used, as follows: (1) Adjust welding current to achieve proper penetration at a travel speed of approximately 6 to 12 inches per minute, (2) On thin material, strike the arc on a carbon steel block or weld fixture and jump the arc to the start of the joint. On thick material, start the arc in the groove on the side wall. Do not start the arc on the material outside of the weld zone., (3) Avoid crater cracks by reducing the size of the weld pool before breaking the arc, either by increasing travel speed or by reducing weld current to very low levels, (4) Use filler metal when weld reinforcement is required, where fit-up is poor and at the end of joints, (5) Keep the arc length short to help maintain a low heat input and prevent atmospheric contamination of the shielding gas. Do not hold the torch at too acute (sharp) an angle, because this can aspirate air into the shielding gas stream and (6) Use gas backup (purge) wherever possible. This helps to prevent oxidation of the root side of the weld which lead to loss of corrosion resistance."