SUPER-LONG THERMAL INSULATION STEEL JACKET PIPE AND MACHINING PROCESS THEREOF

摘要

The present invention discloses a super-long thermal insulation steel jacket pipe and the machining process thereof. The pipe has relatively good thermal insulation performance and corrosion resistance. Because an annular cavity (3) of the pipe is in a vacuum state, the pipe is internally provided with a support frame (5, 6) and filled with a phase change material. When the pipe is used for underground energy exploitation, temperature in a working steel pipe (1) in the pipe can be effectively kept unaffected when external temperature decreases. The steel jacket pipe in the present invention has long service life, and can greatly reduce costs of exploitation of petroleum and an underground heat source and reduce a heat loss in exploitation.