WELDING APPARATUS AND METHOD FOR WELDING TUBULAR END PORTIONS

摘要

A method and apparatus for joining a pair of abutted thermoplastic end portions 38, 40 utilises a transparent sleeve extending around the outer surface of the tubular end portions to be joined and a mandrel 150 on the inner surface. An infrared heater 136 provides radiant heat through the transparent sleeve 116 to melt and fuse the tubular end portions 38, 40. The tubular end portions 38, 40 may be visually monitored through the visually transparent sleeve 116 during the welding process. The method is particularly suitable for weld melt processable fluoropolymers such as perfluoroalkoxy (PFA). The abutting tubular end portions may be compressed together during heating by a rod assembly inserted axially through the two end portions and through the mandrel. The rod assembly having members to engage the two tubular portions for the application of a compressive force thereto. (See figure 20. Not shown). The mandrel 150 use in the welding system may be soluble in fluid for removal from the welded end portions. The tubular end portions may be part of a piece of tubing or pipe or other piece of tubular equipment to be connected.