Welding for pipe and plate used to form pipe plate for heat exchanger, comprises expanding end of pipe in oversize hole in plate and then heating

摘要

A pipe (4) is inserted into an oversize hole (3) in a plate (2) and the end of the pipe is expanded in order to form a ring contact with the inside of the hole (9) and then the pipe end surface (6) and inside wall of the hole are welded together. Forming a welded joint between a pipe and a pipe plate comprises: (a) forming a smooth surface at one end of the pipe; (b) inserting the pipe into an oversize hole in the plate so that the pipe end surface is located below the plate surface (5); (c) bending the end of the pipe outwards so that part of the outside of the pipe forms a ring in contact with the inside of the hole; (d) heating the pipe end surface and inside wall of the hole to a melting point temperature; and (e) and supplying a welding material to the molten material. An independent claim is also included for a pipe plate (1) for a heat exchanger obtained using the above process.