D1.1 with foreign equivalents 2

[Mr168]

I have three materials at hand, JIS-SS400, Q435, and Q235 all for a basic structural application. The vendors supplying the steel have been less than cooperative thus far.

I have yet to find any information other than their basic composition tying them to a UNS number or ASTM equivalent. Am I looking at having to qualify new procedures to allow our guys to weld on any of these per D1.1, or is there any literature out there with the equivalents of these steels that will allow me to use our prequalified procedures?

Thanks in advance.

 

[gtaw]

The easiest way around this mess is to qualify the WPSs using the materials you propose to use. The fly in the ointment is that the materials have to have published mechanical properties.

AISI steels typically are not required to meet any minimum mechanical properties. That is one reason they can not be used for structural applications with prequalified status.

Best regards - Al

 

[Mr168]

I agree completely. If, however, there was a UNS number I could use to skirt the issue, I would. The structural engineers on site at the project were unaware that we couldn't begin welding on something that was "close enough", and did not plan accordingly. It is now having an impact on production.

Just another one of those lovely oversights.

 

[gtaw]

A UNS number only compares base metals on the basis of chemistry, not mechanical properties. It does not take into consideration the state of heat treatment that will impact the mechanical properties of the carbon based iron alloy systems.

The fact that the two base metals are assigned the same UNS number does not infer they have equal weldability and is permitted as a prequalified material only when blessed by the Engineer for auxillary attachments when working with AWS D1.1.

Best regards - Al

 

[Mr168]

Thank you for the reply. Looks like they have some PQR's and welder quals to perform.

 

[bigjack1952]

What is going on with this Asian crap! anyway
I am experiencing the same issues read in your previous forum on Q 235 material. Jusr received a call from client in Martinsburg, W. Virginia regarding welds completed on Q 235 material were cracking and the supplier has no answers and not willing to become involved.

I have a few Questions (Hopefuully this reaches you?)
1. What Filler Metal/Electrode/Wire did you use to weld this mat'l?
2. Did you have to perform any Preheat and/or PWHT?
3. What ASTM Mat'l did this closely match? A36, A106? I see in several email searches that these Mfgr's are claiming Q 235 is equal to A106, A53, A36? all over the board

Look forward to a response

 

[Mr168]

We qualified a procedure for Q235B. There is no "spot on" ASTM equivalent, but it was close enough for us to treat it as we do all other P1 materials. We ended up running PQR's in accordance with D1.1 following the standard preheat requirements (50/100/150) for carbon steel using both E7018 and E71T-1M. The procedures were qualified without PWHT.

Unfortunately, the "to the cheapest bidder" mindset is certainly haunting us these days. The steels from the Asian market cause downtime as we try to qualify procedures, supports and hangers sub'd to Europe only create further qualification concerns along with misfabricated parts due to improper US customary to metric conversions... it undoubtedly creates quite a headache.

 

[bigjack1952]

Mr168,
Thanks for the post.
I am curious about Q 235 falling under P1 Material? if this is correct, then our WPSs/PQRs using Group P2 to P2 would also qualify Q 235 if it is a Group P1 Mat'l, Yes/No?

Thanks again for the update

 

[racookpe1978]

In appreciation for your efforts.

In Europe, qualifying welders to US-written (old!) WPS qualified by (even older!) QPR's using (very old) WPQ's written to old US standards ......)

Blah.

 

[Mr168]

I thought I had replied to this already, but must have been mistaken.

bigjack: It was not classified as a P1 material. However, in choosing the variables in which to qualify the procedure, everthing mirrored the parameters that we use for all of our other carbon procedures, i.e preheat, interpass temperatures, consumables, etc.

 

[tjrush2000]

We are in the process of placing an order for 304L fabrication to D1.1 and the vendor is suggesting that the material he is purchasing in Japan JIS SUS304L may not show yield strength on the certs.

I am assuming the welding can still be performed to AWS.
Will proceedures need to be qualified on this material?
Will welder qualifications be required?

Any other cautionary notes? I always had a pretty high opinion of Japanese materials and would expect this material to be equivelant to ASTM 240 plate. Comments and experience are appreciated.

 

[bigjack1952]

tjrush2000
Just finished having to deal with the Japanese with Q-235 mat'l verses A36 mat'l
The only option was to run mat'l through the series of qualify procedures, Charpy, NDT, etc... to ensure that it met A 36 standards.

Your trying to ensure 304L will meet US Std, so plan on doing the same.

Good luck

 

[gtaw]

Consider using AWS D1.6 if you are using stainless steel for a structural application.

It is difficult to imagine the supplier will not provide chemistry and mechanical properties for their materials. If that is truly the case, the company, and the client is playing craps with the material.

It is folly to use materials without published mechanical properties for a structural application. That is why most welding standards will not permit the use of "steels" purchased to a UNS or AIS/SAE specification. The mechanical properties are dependent on the state of heat treatment as well as the chemistry. The same material can be supplied in the annealed condition or the quenched condition resulting in differences in tensile and yield strength, ductility, etc., not to mention weldability.

I hope the application is not something that could result in someone being injured as a result of some bean counter not recognizing the importance of ordering the correct material even when a cost increase may be incurred. A small profit margin is preferable to a liability suit and an out-of-business auction.


Best regards - Al