Welding Chromoly To Carbon Steel. A Beginners Guide to Welding Chromoly. The benefit of using 309L is that it.
Preheat is not necessary for tubing under 120 thick however it wont hurt anything either. Low carbon steel may be welded by any of the commonly used welding processes the choice depending upon the section the thickness and quality requirements. You can also use CG-12 which is the cast equivalent to using a 309.
Assuming your using 1 12 tubing Im sure theres alot of people on here that know much more about this than I do.
I bet it spits sometimes. The moly is stronger but at the welded joint without pre and post heat can be verry brittle after welding. The melting point of low carbon steel is about 1539-1515 C. Please be informed that ASTM A335-P11 is not P-Number 11 in ASME Section IX.