| 摘要 |
PURPOSE:To provide titled double-ply pipe which prevents the deposition phenomena of solid carbon at the inside or outside surfaces of pipes surely by press- sticking an Fe-Cr -Ni type austenite heat resistant steel pipe blank material and an Fe-Cr type steel thin- walled blank material to one body via metallic powder or the like which is highly heat conductive and is easy to work plastically. CONSTITUTION:Metallic powder 3 which is highly heat conductive and is easy to deform plastically (e.g.; Cu powder) is coated on the inside surface of the above-described heat resistant steel blank pipe 1, and the above-described thin- walled blank pipe 2 is inserted to the inside surface thereof. Both pipes are superposed concentrically. These two blank pipes which are held superposed are subjected to plug-drawing or the like to expand the pipe 2 assuming an inside layer pipe and to stick it by pressure to the pipe 1, thereby forming these into one body. It is equally well to stick the pipe 1 as an inner layer pipe into the pipe 2 as an outer layer pipe by pressure to one body. Metallic foils may be used in place of the metallic powder. The resultant double-ply pipe is the outstanding pipe for reactors to be used for high temp. thermal decomposition and reforming of hydrocarbon-contg. materials that substitute conventional Fe-Cr-Ni type single layered pipes or centrifugally cast double pipes. |
