| 主权项 |
1. A method for cleaning the seat of a double seat valve, which has two closing members (3, 4) arranged in series and moveable relative to each other, which prevent in the closed position of the double seat valve (1) the overflowing of fluids from a valve housing part (1a; 1b) of a valve housing (10) into another (1b; 1a), which delimit between each other both in the closed as well as in the open position a leakage cavity (5), which is connected with the area surrounding the double seat valve (1) via a discharge bore (3d), which is bordered by a tube shaft designed on the first closing member (3) and fed out of the valve housing (10),
wherein, in the closed position, the first closing member (3) designed as a pusher piston is received in a sealing manner in a connection opening (2c) interconnecting the valve housing parts (1a, 1b) and forming a first seating (2a) and, in the course of its opening movement, comes to rest in a sealing manner in or on a second closing member (4), which is assigned to a second seating (2b), and the second closing member (4) is also transferred to an open position (H) during the further opening movement, wherein the closing members (3, 4) are transferable independently of each other through a partial stroke (T1, T2) respectively gap wide into a seat cleaning position for the purpose of rinsing its seatings (2a, 2b), wherein a seat cleaning flow (R1, R2) generated in the respective seat cleaning position experiences a restriction in a restrictor gap (D1, D2) arranged on the leakage space side on the associated closing member (3, 4) before it enters the leakage space (5) and wherein the first seat cleaning flow (R1) generated by the first closing member (4) experiences a bumpless deflection directed into the discharge bore (3d) on a rotationally symmetrical deflection surface (4d), which is designed in a recess (4b) in the second closing member (4), characterized in that the first seat cleaning flow (R1) is urged through the deflection surface (4d) radially inward and axially to the first closing member (3) up until the exit of the second closing member (4) on a front and radially inside end (4e) of the second closing member (4) located outside the recess (4b). |
