CONNECTION METHOD FOR BRANCH PIPE USING WORK VALVE, AND WORK VALVE USED THEREFOR

To provide a connection method for a branch pipe using a work valve capable of easily performing a valve opening operation on a valve body, and the work valve used therefor.SOLUTION: The present invention relates to a connection method for a branch pipe 10 using a work valve 3 comprising a housing 5 to which a fluid pipe 1 is externally fitted in a sealed state, and a valve body 31 capable of blocking or opening a branch part 5d in the housing 5 in the sealed state. The connection method includes: a hole forming step of boring or cutting the fluid pipe 1 in the housing 5 in an open state of the valve body 31; a connection step of connecting the branch pipe 10 to the branch part 5d of the housing 5 in a block state of the valve body 31; a pressure regulating step of reducing a differential pressure between the side of the fluid pipe 1 and the side of the branch pipe 10, holding the valve body 31 in the block state therebetween, in the housing 5; and a valve opening step of opening the valve body 31.SELECTED DRAWING: Figure 5 【課題】弁体を簡便に開弁操作することができる作業弁を用いた分岐管の接続方法及びそれに用いられる作業弁を提供する。【解決手段】流体管１を密封状態で外嵌する筐体５と、筐体５内の分岐部５ｄを密封状に遮断若しくは開放可能な弁体３１とを備える作業弁３を用いた分岐管１０の接続方法であって、弁体３１の開放状態で、筐体５内の流体管１を穿孔若しくは切断する孔部形成ステップと、弁体３１の遮断状態で、筐体５の分岐部５ｄに分岐管１０を接続する接続ステップと、遮断状態の弁体３１を挟む筐体５内の流体管１側と分岐管１０側との差圧を小さくする調圧ステップと、弁体３１を開放する開弁ステップとを有する。【選択図】図５