From surface reforming of the inside of pipe section or surface reforming or the cleaning device null nozzle of the inside of pipe section which is used for cleaning manner and

摘要

PROBLEM TO BE SOLVED: To provide a method of reforming or washing surface in pipe capable of controlling a collapse region of cavitation air bubble even when an inner diameter of a pipe is different, and to provide a device of surface reforming or washing in pipe used in the method.;SOLUTION: In the method, high-pressure liquid is jetted into a pipe from a nozzle, cavitation is generated around a jet stream of the high-pressure liquid and the surface in a pipe is reformed or washed by a collapse impact force of cavitation air bubble, wherein the collapse region x of cavitation air bubble in the pipe is controlled by controlling a jet pressure p1 of the high-pressure liquid and a pressure p2 in the pipe in accordance with pipe inner diameter D and nozzle bore diameter d. As the result, the collapse impact force of cavitation air bubble can act on the collapse region of cavitation air bubble on a prescribed inner part of the pipe and therefore high-efficient treatment is permitted.;COPYRIGHT: (C)2007,JPO&INPIT