VERFAHREN UND STEUEREINRICHTUNGEN ZUR SITZREINIGUNG VON DOPPELSITZVENTILEN

PCT No. PCT/EP91/01984 Sec. 371 Date Apr. 30, 1993 Sec. 102(e) Date Apr. 30, 1993 PCT Filed Oct. 10, 1991 PCT Pub. No. WO92/08070 PCT Pub. Date May 14, 1992.A process for cleaning the seats of a double seat valve having two independently movable closing elements, each of the closing elements being associated with a respective one of the valve seats, which closing elements can be moved into simultaneous fully open positions when the double seat valve is in an open state, and at least one of the closing elements is movable to a partly open position independently of the other closing element, in which partly open position a passage is defined between said at least one closing element and the seat associated with said at least one closing element, comprising: periodically alternately moving said at least one closing element to the partly open position and reversing the moving to move said at least one closing element to the closed position in partial stroke movements, the reversing of partial stroke movements of the closing elements from opening to closing movement and from closing to opening movement is done by a control unit in response to the passage of time, to the closing elements attaining predetermined positions, or as a function of the flow of cleaning agent.