Bob - I'll check with Taylor. He doesn't use steam - but a long stainless trough he had welded up for a tank, with an upsidedown V of the same thin stainless for a lid.

Under the tank, is a long tube with small holes drilled in it with the end of the tube attached to a propane tank. The holes- perhaps 1/8" in diameter emit flame the full length of the tank, as it is long enough to rust-blue barrels up to 48" long.