PIPE WASHING METHOD

PROBLEM TO BE SOLVED: To more reliably remove foreign matters from a water flow channel. SOLUTION: A flowmeter 20 and an in-line filter apparatus 10 are installed in the downstream side terminal of a block water pipeline. The in-line filter apparatus 10 is equipped with a filter 5 having a function of trapping foreign matters, a freely openable or closable drainage pipe 9 and a filter back washing drainage pipe 8 installed in the upstream side and the downstream side, respectively, while sandwiching the filter 5. At the time of washing a pipe, both drainage pipes 8 and 9 are alternately opened based on the numeral value shown by the flowmeter 20 to increase the flow speed in the water flow channel to promote removal of the foreign matters by the increase of the flow speed. Further, a flow channel from which the foreign matters are to be removed is specified by operation of a switch valve installed in the middle of the block water pipeline and another flow channel is closed to further increase the flow speed. Furthermore, since the filter 5 of the in-line filter apparatus 10 is positioned in the downstream side of the pipe washing position, the foreign matters can be trapped and prevented from flowing to the flowing water pipe P in the downstream side. COPYRIGHT: (C)2009,JPO&INPIT