GB868288A - Improvements in or relating to the removal of water from fibrous material and wet presses therefor - Google Patents

Abstract

868,288. Wet presses. LIPPKE, P. Nov. 25, 1958 [Dec. 19, 1957], No. 37915/58. Class 96. In a wet press for removing water from a web of fibrous material, e.g. paper pulp, the web, supported on a felt 5, is fed into a nip, which is insufficient to bank back water, between the rigid, e.g. metal, surface of a main roller 1 and a felttensioning and guide roller 3, and follows an arc of the surface of the roller 1 to a second nip between this roller and a cooperating pressure roller 2, water being pressed out only through the felt; preferably the web is then continued around the roller 1 to a further nip or nips between the main roller and a further pressure roller or rollers, e.g. roller 4 (Fig. 2). The rollers 2, 3, 4 are preferably rubber surfaced, pressure-adjustable by mechanical, pneumatic, or hydraulic means, e.g. as at 32, 33, 34, and adjustably driven together by belts 6, 7. The extraction of water from the paper web may be facilitated by an endless, incompressible sieve cloth 8, e.g. of metal or plastic mesh, supporting the felt 5, and passing therewith through the nips and in tensionadjustable manner around idle rollers 9, 10, 11, and also by warming the water in the web by electric heating, as described in Specification 774,227. A doctor mechanism comprising a blade 13 in a holder 14 mounted on an arm 15 restores fibres adhering to the roller 1 back to the web, such fibres, by piling up against a rail 20, actuating a relay 21 which in turn causes a solenoid valve 23 to transmit pneumatic or hydraulic pressure to a cylinder 18 to withdraw a rack 17 which through a bearing 16 causes the arm 15 to move from against a stop 19 to a position against a stop 25, indicated by the dotted line position in Fig. 2; the actuated relay 21 also supplies current through a time delay relay 26 to a solenoid valve 27 which permits compressed air to flow via a tube 28 to the enclosure of the holder 14 to blow away and deposit the fibres on to the web, their removal causing cessation of the actuation of the relay 21 and consequent return of the arm 15 to against the stop 19.