"金属蛇形管" can be translated as "metal serpentine tube" or "metallic corrugated/flexible tube (if emphasizing its flexibility or corrugated shape resembling a serpent)".
"Metal serpentine tube" directly conveys the idea of a tube made of metal with a serpentine (snake-like, winding) shape.
"Metallic corrugated tube" or "metallic flexible tube" could also be used if the focus is on its corrugated structure or flexibility, though these terms are slightly broader and may not strictly imply the serpentine shape.
The most precise and literal translation for "金属蛇形管" is "metal serpentine tube".