CLEANING METHOD FOR DRAIN PIPE

PROBLEM TO BE SOLVED: To provide a cleaning method for a drain pipe that spreads a small amount of chemical readily and uniformly over an entire inner peripheral surface of a drain pipe of a toilet bowl, thereby effectively removing urinary calculus.SOLUTION: A cleaning method is for a drain pipe 20 that drains sewage from a toilet bowl 10 installed on each floor by leading the sewage to a horizontal pipe 21, and from the horizontal pipe 21 to a vertical main pipe 23. The cleaning method comprises: a urinary calculus softening step in which a chemical spraying nozzle of chemical injection means is inserted from a cleaning port 27 provided in the vertical main pipe 23, for spraying a urinary calculus softening agent from each of injection ports onto urinary calculus adhered on an inner wall surface of the vertical main pipe 23, thereby softening the urinary calculus; a neutralization step in which a neutralizing agent is injected into the vertical main pipe 23 for neutralizing the urinary calculus softening agent; and a high-pressure water cleaning step in which a high-pressure water injection nozzle of high-pressure water supply means is inserted from the cleaning port 27 provided in the vertical main pipe 23 for spraying high-pressure water and cleaning the inner wall surface of the vertical main pipe 23, thus removing the softened urinary calculus. The horizontal pipe 21 is cleaned in the same way.SELECTED DRAWING: Figure 1 【課題】少ない薬品の量で便器の排水管の内周面全体に容易に万遍なく薬剤を付着することができて効果的に尿石を除去できる排水管洗浄方法を提供する。【解決手段】各階に設置されている便器１０からの排水を横管２１に導き、横管２１から更に立本管２３に導いて排水する排水管２０の洗浄方法である。立本管２３に設けた掃除口２７より薬剤注入手段の薬剤散布用ノズルを挿入して各噴出孔から尿石軟化剤を散布することで、立本管２３の内壁面に固着した尿石に尿石軟化剤を付着させて尿石を軟化させる尿石軟化工程と、立本管２３内に中和剤を投入して尿石軟化剤を中和させる中和工程と、立本管２３に設けた掃除口２７より高圧水供給手段の高圧水噴射ノズルを挿入して高圧水を噴射させて立本管２３の内壁面を洗浄することで軟化した尿石を剥離する高圧水洗浄工程とを具備する。横管２１についても同様に洗浄を行う。【選択図】図１