40 Disassembly of products for others; Pipe tapping services, namely, drilling or cutting holes in pressurized pipes without draining or spilling the contents of the pipes; Refining of metals; Welding; Welding for construction and repair purposes; Welding services; Welding services for construction and repair purposes; Custom manufacture of general product lines in the field of steel pipe and tubing; Dental scrap refining; Metal welding