Welding method for ultra-thin composite layer low-carbon steel - austenitic stainless steel multiple tube adaptor

The invention discloses a welding method for low carbon steel-austenite stainless steel compound pipe of ultra-thin stainless composite bed. The character is: the welding is completed with transition layer welding seam and base layer welding, it hasn't single stainless steel composite bed seam; the welding rod for low carbon steel base layer seam is the same to the one for mother metal; the first welding for stainless steel composite layer and the transition layer between the stainless composite layer and the low carbon steel base layer use argon tungsten-arc welding with back argon filling protection, or uses manual arc welding; the welding wire or welding rod use stainless steel in order to form the transition welding seam; after the transition welding seam is completed, the second time uses manual arc welding to weld the low carbon steel base layer, the welding rod uses low carbon steel in order to form base layer welding seam.