Welding Pre-1920 Steel to New Steel 1

[Deutero]

I am asking this question for PT999 as well as myself. PT999 has posed a similar question at thread507-167093.

Can an existing 15" wide flange erected in 1907 be field welded to a new A992-Gr 50 wide flange?

What material would the 1907 beam be composed of?

Thank you ...

 

[unclesyd]

I would do this before cutting out a piece to test.

A quick test to see if it is readily weldable is to make a one side fillet weld,7018 electrode, a 1/4" 2"x2" tab in an inconspicuous place and try to forcibly remove it.
Try first in the hard direction, hitting one time on the weld side. Then hit it from the easy side. It shouldn't break out the hard way. The weld should fail hitting from the easy side.

 

[metengr]

Have you also considered a bolted flange connection versus welded?

 

[deanc]

I would suggest first pass of E6010 P5 then the "half bead" method as described in the NBIC. E7018 to finish.

Be careful that it is not cast or wrought iron.

 

[metengr]

deanc;
FYI. We (the NBIC) deleted the half-bead temper bead procedure after the 2004 Edition of the NBIC because it is not really as effective as a temper bead procedure. Also, those darn metal burrs that are generated after grinding that first pass are a killer.

 

[deanc]

metengr

Knew it was gone---but I think it is still the best way to go in some cases.

I have found that with some of this old steel(locomotive fireboxes esp.) that a bead of say 7018 will not tie in. If you lay down a layer of 6010 and grind half of it away you end up with a more weldable surface.

So that is the reason I suggested the "half bead". I do agree the temper bead is better if you wish to avoid PWHT.

 

[gtaw]

In general, structural steels produced earlier than the 1940's did not have to control sulfur or phosphorus. They only had to meet minimum tensile strength requirements. Another property the early steels didn't have to contend with is notch toughness.

A36 steel was developed in WWII to improve weldability and to bypass government fixed prices. It was new, improved, and was not included in the pricing schedules published by the War Department.

The suggestion that you limit the filler metals to the low hydrogen type is good advice. The other piece of advice I would offer is to take a sample and have a chemical analysis performed. The cost of obtaining the sample will be more that the actual chemical test, but well worth the effort. I would also suggest that you compare the various electrodes offered by the different manufacturers. Many manufacturers make more than one type of E7018 electrode. Likewise compare flux cored electrodes if you decide upon using the FCAW process. Select a filler metal with a manganese content that is at least ten times the sulfur content of the steel you are trying to weld. Use the low hydrogen electrode such as E7018-H4 or use a second generation flux cored electrode that will meet the low hydrogen requirements (not all flux cored electrode are created equal). The low hydrogen filler metal is necessary because most early steels had "higher" carbon content than most modern construction steels. Also, the chemical analysis will be useful in determining the minimum preheat temperature. I prefer to use the "Alternative Methods for Determining Preheat" found in Annex XI of AWS D1.1-2002 (for example). The details are in paragraph X16.2.2 and Tables XI-1 and XI-2.

The sulfur and phosphorus can lead to hot cracking. The higher carbon content can result in delayed cold cracking. The higher manganese will help mitigate the problems associated with sulfur. The high preheat and low hydrogen electrodes (properly stored on the job site at 250 degrees F) will minimize the delayed cold cracking problems associated with the higher carbon content often associated with early steels.

The last bit of advice I would offer is to have an AWS Senior CWI watch over the welding to provide a level of assurance the work is performed in accordance with a written welding procedure specification.

Ok, let this be the last bit of advice. Wait at least 48 hours to have the welds inspected using the magnetic particle test method if the welds are fillet welds or the ultrasonic test method if the welds involve complete penetration groove welds. The NDT technician should be certified by ASNT as either ACCP Level II or ACCP Level III. The reasoning is that the ACCP certification involves third party certification rather than only employer certification as is the case with NDT certification to SNT-TC-1A or CP-189.




Best regards - Al

 

[deanc]

gtaw

Nice reply,if in doubt ask a welding eng. Star for you.

 

[gtaw]

I'm not really a welding engineer, but I did stay in a Holiday Express last night!

Best regards - Al