I’m building a process for welding heavy assemblies.
(2) W14x550 x 41’ beams with 2” crossmembers
I only have 12” between the flanges and my preheat/interpass is 300 degrees.

I essentially have a 300 degree box, 12x16x24 deep
I need to put 5/8” fillets in hundreds of these sections.

Does anyone make liquid cooled sleeves?
How can this be done?