Abstract: In a papermaking machine for forming tissue paper, a turning bar is disposed having a curved surface about which a web of tissue paper is turned. The bar has an internal air plenum which supplies air to two sets of holes or slots. The first set is arranged to direct air normal to the curved surface of the bar or in the machine direction, the second set is arranged to direct air toward the edges of the tissue which is turned around the bar. The second holes or slots produce air jets which apply a cross machine direction tension to the web which prevents wrinkling of the web. The first set of holes or slots forms jets of air that prevent the tissue web from contacting the turning bar.

Abstract: Two racks of parallel screening bars each have rigid rack frames which extend beneath the bars. Two crankshafts with offset cam surfaces are mounted to the machine frame, and the rack frames are mounted by bearings to the crankshaft cam surfaces. The rack frame bearings are closely spaced beneath the bars to balance the system, while the rack frames provide a stiff oscillatory platform for the bars, permitting narrow gauge bars and increased screening area. The rack frames also include counterweights to dynamically balance the system.

Abstract: Radially spaced calibration holes are drilled parallel to the exterior surface of a cylindrical shell for a dryer roll. An ultrasonic transducer is mounted in a fixture filled with a coupling medium which allows for adjustment of the spacing and angle of the transducer which traverses the shell as it is rotated. The transducer produces a signal directed to the shell. A computer calculates the time the signal takes to travel from and return to the transducer and the depth of the shell from which the signal returns. A clear signal corresponding to holes up to one inch from the surface are found by adjusting the ultrasonic transmission angle. This angle is approximately 23 degrees from a normal to the casting surface. The calibrated transducer traverses the surface of the shell. The signals are gathered and stored to create data which may be used in maintaining the shell for the dryer roll.

Abstract: A drying section apparatus is disclosed for drying a web of paper. The apparatus includes a size press for applying size to at least one side of the web. A single tier dryer is disposed downstream relative to the size press for drying the web. The single tier dryer includes a plurality of dryer cylinders and a plurality of vacuum rolls. Each of the vacuum rolls is disposed between adjacent dryer cylinders of the plurality of dryer cylinders. A dryer felt extends around at least one of the dryer cylinders. The arrangement is such that at least one of the dryer cylinders is top felted for permitting downward removal of broke. An air cap is disposed above at least one of the dryer cylinders for blowing air through the felt for drying the web disposed between the dryer cylinder and the felt. The arrangement is such that both sides of the web are dried during passage of the web through the single tier dryer.

Abstract: A process for drying a wet material in a drying system includes supplying a current of heated gas to a dryer from a combustion chamber. The material is exposed to the current in the dryer. The dried material is separated from the current of heated gas. The current of heated gas is split into a first stream of heated gas and a second stream of heated gas after the dried material has been separated. The first stream of heated gas is introduced into the combustion chamber so that the first stream is further oxidized therein. A third stream of heated gas is removed from the combustion chamber. The third stream includes at least a portion of the first stream. The second stream of heated gas is introduced into the combustion chamber so that it makes up a portion of the current conveyed to the dryer.

Abstract: A controlled deflection roll has a roll shell which is hydrostatically radially supported by internally disposed hydrostatic shoes. In order to axially position the roll shell, a mechanical locating link is provided which is disposed externally of the roll shell. The link is coupled at one end to an element attached to the roll shell, and is coupled at an opposite end to a fixed support, such as a floor stand. The end of the roll at which the locating link is disposed is thus axially fixed, while the opposite end of the roll remains free to float. The locating link can be connected to an oscillator to oscillate the roll shell axially during operation so as to distribute any non-uniformities in the roll shell and thus to mitigate their effect on the sheet.

Abstract: A loose joint assembly for linking two segments of a shaft which are substantially aligned at either end of the joint assembly co-axially about a axis of rotation. The joint assembly includes a male coupling member disposed co-axially within a female coupling member with an intermediate bearing member to align the coupling members. The male coupling member has a plurality of circumferentially spaced flats located within the space enclosed by the female coupling member. A corresponding plurality of openings, preferably in the form of slots extending in the circumferential direction, are located in the female coupling member, each slot being aligned with a corresponding flat. A drive pin is attached to the male coupling member at each flat and extends radially from the flat and at least partially into the corresponding slot in the female coupling member.

Abstract: A flexible blade is used as a metering device by being inserted at a nip formed between a radiused profile portion of a fixed, rigid loading element and a substrate roll. The flexible blade is forced to take the shape of the profile portion at the nip, and thereby meter the coating to a desired thickness and consistency. Inflatable air tubes engage the loading element to adjust the overall thickness of the coating.

Abstract: An extended nip press apparatus is disclosed for pressing a web of paper extending therethrough. The apparatus includes a rotatable backing roll and a press shoe having a concave surface which cooperates with the backing roll. The arrangement is such that the concave surface and the backing roll define therebetween an elongated pressing section for the passage therethrough of the web. The shoe includes an upstream portion and a device for urging the upstream portion toward the backing roll. A downstream portion extends from the upstream portion, the downstream portion being resiliently disposed relative to the upstream portion. A further device selectively urges the downstream portion toward the backing roll for controlling a pressure profile applied by the shoe to the web for inhibiting delamination of the web.

Abstract: A single drive motor is connected by a speed reducer directly to the shaft of one roll of the two aggressive surfaced rolls which form a chip destructuring nip. One roll is dynamically positionable perpendicular to its axis of rotation to open and close the nip. Each roll turns on a shaft positioned along the axis of the roll which is mounted to a frame by bearings. Only the non-positionable roll is driven directly by the drive motor. The roll which is dynamically positionable is driven by a tire arrangement mounted about the axes of the rolls. Opposed tires mounted on the spaced apart parallel shafts form a clutch-like means for driving the dynamically positionable roll.

Abstract: A rectangular clarifying tank has an inclined beach formed of sheet metal and having 575 holes per square inch, each hole having a diameter of 20 thousandths of an inch. Two side chain drives advance several scrapers along the beach. Each scraper has a rotatable knurled pipe which turns the sludge and aids dewatering through the beach. The sludge removed from the clarifier has a solids content of between eight and twelve percent. Additional dewatering may be accomplished by applying a vacuum to the last one-quarter of the beach. A tray positioned beneath the beach collects water which drains through the beach. The drain water may be returned to the clarifier tank or may be directly treated as clarified water.

Abstract: A trash conveyor has thin upstanding right triangular teeth mounted parallel to their direction of motion. A pivoting deck is positioned over the conveyor and has fixed isosceles-triangular teeth which interdigitate with the teeth on the conveyor. The deck is angled upwardly towards trash infeed end of the conveyor. The deck is suspended by four pivot arms arranged in a rectangular pattern which allow the deck to pivot up and in the direction of the motion of the conveyor. Rows of teeth attached to the deck are offset from previous rows so that the spaces between the teeth on the deck and the teeth on the conveyor varies as the teeth on the conveyor move under the deck. A blade cleaner and conveyor is located beneath the trash conveyor which removes plastic bags from the teeth of the trash conveyor and rolls them into compact shapes to facilitate disposal for recycling.

Abstract: A cleaning apparatus is disclosed for cleaning a forming wire of a paper machine. The apparatus includes a shower which is disposed adjacent to the forming wire for applying a shower of cleaning fluid to the wire. A blow box is disposed closely adjacent to the forming wire and downstream relative to the shower. The box is connected to a source of pressurized air for blowing a jet of air through the wire for removing the cleaning fluid therefrom. A plate is disposed between the box and the wire. The plate defines a plurality of slots which are disposed obliquely to a direction of movement of the wire in order to supply a multiplicity of pressure pulses to the wire for removing contaminants therefrom.

Abstract: A press of the Beloit Extended Nip.RTM. type has a nip defined between a backing roll and an elongate shoe. A paper web travels on a dryer felt through the nip and is supported over the shoe by a bearing blanket. The shoe has a rigid concave core to which is fixed a layer of compliant material which defines a concave surface. Lubricant is introduced between the compliant material and the bearing blanket to form a hydrodynamic fluid film. Preferably the rigidity of the compliant material is of the same or lesser order of magnitude than the rigidity of the fluid film at the center of the shoe in the machine direction, such that the fluid film at the nip causes a depression in the compliant material which is filled with lubricant. The thickness of the lubricant is thus greater at the center of the shoe than at regions outward from the shoe center and the escape of lubricant from the shoe is retarded. The compliant material comprises an elastomer with a low coefficient of friction and high abrasion resistance.

Abstract: A bar screen is combined with a wire or punch screen which is suspended beneath the screen deck from a pair of oscillating bar support beams so that a single bar screen, screen combination, may not only size materials for thickness but remove small particulate material from the chips or materials which pass through the screen deck of the bar screen.

Abstract: A method for reusing spent gas from an ozone bleaching reactor includes steps for removing lint from the spent gas, compressing it, passing it through a reactor in which hydrocarbons and carbon monoxide are destroyed by oxidation, and cooling the gas. Injecting the gas together with compressed air into a mist separator for removal of any mist from the gas and then passing the gas through a pressure swing adsorption device in which nitrogen, carbon dioxide, trace water vapor, and other trace elements may be removed by adsorption on a molecular sieve material. The recycled gas is fed to an ozone generator and from there to an ozone/pulp bleaching reactor. By appropriate selection and layering of molecular sieve materials in the pressure swing adsorption device, it is possible to provide selective removal of a variety of gaseous elements from a gas stream.

Abstract: A method and apparatus for bleaching high consistency pulp with a gaseous bleaching reagent. The pulp is shredded and then fluffed in the presence of a contacting gas which includes the gaseous bleaching reagent within an upstream vessel comprising a pin/foil contactor so as to suspend the pulp in the contacting gas and react the bleaching reagent with the pulp. The pulp is retained in the contactor for a predetermined time which is sufficient to consume about 75% to about 90% of a selected dose of the gaseous bleaching reagent which is required to delignify the high consistency pulp from an initial Kappa number to an intermediate Kappa number. The pulp and contacting gas are then separately supplied to a porous bed reactor where the reaction of the selected dose of the gaseous bleaching reagent with the pulp is substantially completed so as to further delignify the high consistency pulp from the intermediate Kappa number to a final Kappa number.

Abstract: An integral outboard bearing support for a gear reducer on a papermaking machine oscillating doctor. The bearing support rotatably supports a distal end of the gear reducer's drive shaft to reduce deflection and fatigue. The outboard support also aligns internal bearing supports with the outboard support to optimize performance by preventing current reducer shaft and support bearing failures.

Abstract: A method and apparatus for bleaching high consistency pulp with a gaseous bleaching reagent. The pulp is shredded and then fluffed in the presence of a contacting gas which includes the gaseous bleaching reagent within an upstream vessel comprising a pin/foil contactor so as to suspend the pulp in the contacting gas and react the bleaching reagent with the pulp. The pulp is retained in the contactor for a predetermined time which is sufficient to consume about 75% to about 90% of a selected dose of the gaseous bleaching reagent which is required to delignify the high consistency pulp from an initial Kappa number to an intermediate Kappa number. The pulp and contacting gas are then separately supplied to a porous bed reactor where the reaction of the selected dose of the gaseous bleaching reagent with the pulp is substantially completed so as to further delignify the high is consistency pulp from the intermediate Kappa number to a final Kappa number.

Abstract: A chip slicer has pivotably mounted chip-forming knives located so that the knife edges are in a plane which passes through the axis of rotation of the knives, as well as through the axis of pivoting. Another improvement is to employ a knife which has a blade which is bent at an obtuse angle to form a first and a second leg. The first leg has a cutting edge and an upper surface which defines a chip path. The second leg is bent with respect to the first leg in the direction of rotation of the knife ring. The knives are mounted to the ring by clamping wedges which are bolted to the knife ring so that they overlie the second leg and so clamp the knife blade by the second leg to thereby substantially remove obstructions from the chip path. A further improvement has chip depth gauges which are positioned in front of the knife edges. The depth gauges have trailing edges in the direction of rotation which extend substantially parallel to the upper surface of the blades.