PURPOSE: To provide a process for producing a different material pipe joint of a large diameter having excellent joinability and joint strength.
CONSTITUTION: A cylindrical intermediate layer material 12 consisting of a zirconium material or titanium material is fitted to the outer side of a cylindrical inside layer material 11 consisting of a stainless steel or nickel-base alloy and further, a cylindrical outside layer material 13 of the same kind as the kind of the inside layer material 11 is fitted to the outside surface side thereof. A tantalum layer 14 consisting of Ta foil is interposed in the respective joint surfaces, by which a fitted and assembled material 10 is formed. After this material is heated, the material is rolled by a cross helical rolling mill having three pieces of cone-shaped rolls, by which the respective layer materials are joined and a clad pipe is formed. The one end side of the clad pipe of a prescribed length is removed in such a manner that the outside layer 13 remains and the other end side is so removed that the intermediate layer material 12 remains. The different material pipe joint is thus produced.
IKENAGA YOSHIAKI
TAKEDA SEIICHIRO
NAGAI TAKAYUKI
DORYOKURO KAKUNENRYO