Abstract: A headbox of a paper machine has a stock distribution header part, a distribution pipe assembly connected to the stock distribution header part, an equalizing passage following the distribution pipe assembly in the flow path of the stock suspension, an air tank in immediate communication with the equalizing passage and a converging slice part following the equalizing passage, the converging slice part having a lower lip wall and an adjustable upper lip wall. A turbulence section between the equalizing passage and the converging slice part has at least one exchangeable grating cassette consisting of at least two grating plates in abutment with each other. A first of the grating plates and in the direction of the stock flow and has a plurality of apertures formed therethrough.

Abstract: A paper machine has an equalizing part between a distribution pipe system part and a turbulence section in the flow path of the pulp stock. The equalizing part has an equalizing chamber with a length in the direction of flow of the pulp stock and a front wall. An adjusting device is coupled to the front wall of the equalizing chamber for adjusting the length of the equalizing chamber by adjustment of the position of the front wall.

Abstract: Quick connect apparatus for headbox components in a paper making machine, e.g., apparatus to quickly connect and disconnect the equalizing chamber portion of the air cushion damper from associated distribution header and turbulence sections of the machine, include an elongate locking rod extending over a substantial portion of the end region of the components to be attached, the locking rod being mounted for longitudinal movement. The locking rod is provided with spaced locking portions adapted to lockingly engage correspondingly spaced portions of adjacent components to which said component is to be attached. The components are quickly connected in one embodiment by the longitudinal movement of the elongate locking rod or, in another embodiment, by the rotational movement thereof, whereby the locking portions on the rod are moved into and out of locking engagement with the corresponding spaced locking portions of the other component.

Abstract: An apparatus for damping pressure fluctuations in the pulp-suspension flow of a paper machine includes a pipe system which delivers the pulp suspension to a headbox and in the interior of which the pulp suspension flows toward the headbox. A portion of the pipe system is surrounded by a gas, such as air, which is under pressure and which is situated within a suitable enclosure. This portion of the pipe system is formed at least in part by an elastic wall structure, the inner surface of which engages the pulp-suspension flow and the outer surface of which is exposed to the gas under pressure. Thus, the elastic wall structure changes its configuration or geometry due to pressure fluctuations in the pulp-suspension flow while the gas under pressure which acts through the elastic wall structure on the pulp suspension serves to damp the pressure fluctuations.

Abstract: A headbox of a paper machine includes a header chamber for receiving pulp stock, a distribution pipe system for receiving pulp stock from the header chamber, a flow-equalizing chamber for receiving pulp stock from the distribution pipe system, a turbulence passage system for receiving pulp stock from the flow-equalizing chamber, and a lip slice for receiving pulp stock from the turbulence passage system and discharging the pulp stock from the headbox. At least one of the above chambers is defined in part by a movable wall structure which has an inner surface contacting the pulp stock so that this movable wall structure can move in response to pressure fluctuations in the pulp stock. This wall structure has an outer surface which defines part of the hollow interior of an enclosure in which air under pressure is situated, so that through the movable wall structure the air under pressure can act on the pulp stock to damp pressure fluctuations thereof.

Abstract: A paper machine has a headbox provided with a slice through which a pulp suspension discharges from the headbox, this slice being defined in part by an upper lip frame. The pulp suspension flows to the slice from a distribution header and a turbulence passage assembly which receives the pulp stock from the distribution header and continues the flow thereof toward the slice. An air tank is provided for containing air under pressure to act on the flowing pulp stock so as to damp pressure fluctuations in the pulp suspension flow, and this air tank is connected in part to the upper lip frame of the slice so that the pressure in the air tank will act on the pulp suspension in the immediate vicinity of the slice.

Abstract: A paper machine has an enclosure for containing a gas under pressure. A hydraulic headbox of the paper machine includes a slice as well as a conductor structure for conducting suspension to the slice and a distributor structure for distributing suspension as uniformly as possible to the conductor structure to be conducted thereby to the slice. The gas enclosure and distributor structure respectively have hollow interior portions communicating with each other so as to provide for the suspension in the distributor portion a free surface acted upon by gas under pressure in the enclosure so that this latter gas under pressure will act as a gas cushion for damping pressure variations in the stock suspension.

Abstract: An apparatus, such as the headbox of a paper machine, having the capability of compensating for the tendency of a beam to become deflected due to loads, temperature-differential phenomena and the like. A beam is supported at a pair of locations situated inwardly of the ends of the beam but spaced from the center thereof in such a way that due to loads, temperature-differentials, and the like the beam has a tendency to become deflected from a straight condition to a curved condition extending along a curve which passes through the above locations to the ends of the beam. A force structure cooperates with the beam at the region of the ends thereof for opposing the tendency of the beam to assume the above deflected condition so that through this force structure it becomes possible to prevent undesirable beam deflection.

Abstract: At the slice region of a headbox or the like of a paper or equivalent machine, there is a front support structure which has an elongated substantially horizontal lower region situated adjacent an upper lip of the slice. An elongated strip extends along this lower region of the front support structure and projects downwardly beyond the latter where the strip terminates in an elongated substantially horizontal free edge defining the upper lip of the slice. An elongated plate is situated in front of and adjacent the front support structure, extending horizontally across the latter throughout the entire width of the slice, and this plate carries structure for adjusting the strip.