Abstract: Apparatus for supplying deaerated stock to a processing machine incorporates an enclosed receiver and an open receiver open to the atmosphere. Stock deaerated by vacuum in the enclosed receiver flows to the processing machine, preferably via the open receiver. Some of such stock spills over a weir associated with the open receiver to maintain a constant-level pond in such receiver. Such constant-level pond minimizes stock pressure fluctuations at the machine. The apparatus may be provided with devices for controlling the level of stock in the conduit leading from the enclosed receiver and for passing stock from the enclosed receiver to the conduit in a predictable flow pattern to minimize generation of pulsations at the entry to the conduit. The stock spilling over the weir in the open receiver is recycled. During a temporary shutdown of the processing machine, the system may be maintained in operation with continuous recirculation of stock through the receivers to facilitate rapid restarting of the machine.

Abstract: Apparatus for treating a papermaking suspension which includes an elevated receiver mounted at the top of a pedestal structure, there being a plurality of generally vertically oriented cleaners connected at the underside of the receiver and the pedestal structure providing conduit means through which the suspension to be cleaned is conveyed to the cleaners, rejected stock from the cleaners being returned to a subsequent cleaning operation and through which cleaned deaerated stock can be conveyed from the receiver to a point of use such as a papermaking machine.

Abstract: Apparatus for supplying deaerated stock to a processing machine incorporates an enclosed first receiver and a second receiver open to the atmosphere. Stock deaerated by vacuum in the first receiver flows to the second receiver. Some of such stock spills over a weir associated with the second receiver to maintain a constant-level pond in such receiver. Stock is supplied to the machine from such constant-level pond, so that the pond minimizes stock pressure fluctuations at the machine. The stock spilling over the weir is recycled to the first receiver. During a temporary shutdown of the processing machine, the system may be maintained in operation with continuous recirculation of stock through the receivers to facilitate rapid restarting of the machine. Because there is no need for a pond of stock in the enclosed receiver, such receiver may be compact. The system may be installed in a preexisting mill and space within a preexisting vessel may be used for the second receiver.

Abstract: Outflow of liquid from an elevated chamber maintained under a condition of vacuum which outflow is delivered through a dropleg conduit to a point of use at a lower level is effected by establishing a plurality of outflow courses in an upper length portion of the dropleg conduit with entry to such outflow courses being arranged at different elevations within the chamber so that flow through an outflow course cannot occur before first there occurs the filling of outflow courses having entry elevations below the said particular outflow course.

Abstract: More efficient and effective mounting of centrifugal cleaners in a cleaning stage of papermaking apparatus is effected by mounting the cleaners in vertical orientation in a feed plenum in which the inlets to the cleaners are disposed submerged in the papermaking suspension flow in the plenum, the feed plenum being disposed at the underside of a receiver maintained under vacuum to which the accepts from the cleaners discharge, the rejects from the cleaners also discharging to a chamber maintained under vacuum. Additionally, means are provided for readily, removably mounting the cleaners to the plenum structure.

Abstract: Papermaking apparatus in which deaerated papermaking stock is gravity fed from the evacuated chamber of a stock receiver to paper web-forming means through dropleg supply conduit system interconnecting the bottom of this chamber and the exit slot or slice of paper web-forming headbox, the dropleg conduit system having entry communication with the receiver chamber along a substantial part of a major lateral expanse of the bottom portion of the deaerated stock collecting zone thereof, the droplet conduit system preferably having exit communication with the delivery passage of the paper web-forming headbox transversely in the direction of the transverse length of the exit slice. The conduit system is provided such that its flow course between the stock receiver and the web-forming headbox delivery passage has no course deviation laterally of the web-forming means axis.