Welding A1018 HSLAS to A500 Grade C

[EngDM]

We are the EOR on a project and the fabricator wants to substitute our spec'd G40.21 350W to A500 Grade C, and our G40.21 300W plate to A1018 HSLAS Grade 50. As far as strengths are concerned I don't have an issue with it, but I couldn't find any information in the textbooks/references I have regarding whether or not these two materials are suitable to be welded together. I don't typically get involved with weld process and what not, but I'm curious if these can be welded together and if there is a specific weld process requried.

 

[weldstan]

They are weldable to each other.

 

[Twistlock Dynamics]

As the EOR on a project, we were approached by the fabricator to swap G40.21 350W with A500 Grade C and G40.21 300W plate with A1018 HSLAS Grade 50. Strength-wise, no red flags popped up, but I had to dig deeper on weldability. Both are low-carbon steels, so welding is feasible with common methods like SMAW or GMAW. The key is checking carbon equivalents (CE) to avoid cracking and ensuring the WPS is updated accordingly. It’s a solid reminder that material swaps aren’t just about strength. Welding processes and preheat requirements need a second look, too!

 

[EngDM]

As the EOR on a project, we were approached by the fabricator to swap G40.21 350W with A500 Grade C and G40.21 300W plate with A1018 HSLAS Grade 50. Strength-wise, no red flags popped up, but I had to dig deeper on weldability. Both are low-carbon steels, so welding is feasible with common methods like SMAW or GMAW. The key is checking carbon equivalents (CE) to avoid cracking and ensuring the WPS is updated accordingly. It’s a solid reminder that material swaps aren’t just about strength. Welding processes and preheat requirements need a second look, too!

But as the EOR, is it on you to check CE or is it on the fabricator that is proposing the substitution to do this (assuming the shop drawings will be stamped).