Abstract: A single facer for corrugated paperboard of the type using a very large diameter fluted bonding roll and a much smaller diameter fluted corrugating roll which engages the bonding roll to provide a corrugating nip. The small diameter corrugating roll is made to be resilient so that it is capable of inward deflection in the vicinity of the corrugating nip in order to cushion impact as the rolls interengage along the corrugating nip. This cushioning deflection absorbs vibrational movement due to chordal action of the interengaging flutes, and thereby reduces noise levels, roll wear and improves the quality and consistency of corrugation.

Abstract: A method and apparatus for producing a single face corrugated web in which a steam cloud is injected between the corrugated medium web and the liner web directly at the line along which the webs converge. This type of steam injection allows faster corrugator speeds without sacrificing bonding quality. An adhesive slurry of water and starch granules is applied to the flute tips to form glue lines on the corrugated web prior to the convergence of the webs. The injected steam cloud directed at the web convergence line adds heat without promoting premature dehydration to facilitate proper conditions for effective cooking of the adhesive slurry to thoroughly gelatinize the adhesive. In some applications, dry steam is preferred because dry steam does not significantly interfere with subsequent dehydration of the adhesive gel during the formation of the initial green bond.

Abstract: A method and apparatus for producing a single face corrugated web from an adhesively bonded liner and medium web without the use of a pressure roll nip where the liner web is joined to the medium web. A heated bonding roll with a fluted outer surface carries the single face web around a circumferential portion sufficient to create a green bond in the glue lines before the web is removed from the roll. The bonding roll may be internally heated or a steam chamber may be positioned around a portion of a lower bonding roll, such that the steam chamber introduces a supply of steam into contact with the single face web while the single face web is in contact with the outer circumference of the bonding roll. An adjustable wrap arm places the freshly glued single face web in contact with the bonding roll and tension in the liner web is controlled to adjust the radial force applied to the glue lines.

Abstract: A rotary bristle brush, particularly adapted for use in a decelerating conveyor for shingling sheets, operates over a preload surface that subjects the moving bristles to an increasing bending deflection. The bristles are released from the preload surface just above the sheets entering the shingling conveyor to allow the ends of the preloaded bristles to spring downwardly into contact with the sheet. The contact force of the bristles helps drive the sheet downwardly onto the shingling conveyor which may be a vacuum conveyor.

Abstract: A vacuum-assisted hot plate is used to precondition webs, such as paper webs used in the manufacture of corrugated paperboard. The vacuum-assisted preheater has a web supporting and heating surface separated into four sections, namely: an input section, a central upstream section, a central downstream section, and an output section. The sections are separated by three vacuum channels that are sized wide enough to prevent clogging from paper dust. The central upstream section and the central downstream section have convex surfaces. Vacuums applied to the vacuum channels provide a normal force to pull the traveling web against the heated surface, whereas the convex configuration of both the central upstream section and the central downstream section provide a normal force pushing on the paper web in the opposite direction. The result is effective positive contact of the traveling web against the heated surface, thereby promoting effective heat transfer.

Abstract: A gapless order change in a continuous running corrugated web is provided by utilizing a partial web sever extending transversely across the web upstream of a web selector device. The partial web sever allows the output web selector device to be readjusted downstream of the slitter-scorer to redirect the output webs between upper and lower cut-off knives as required. The partial web sever allows the order change to be effected with a continuous unbroken web containing the outs for the cut-off knife level handling the output web portions opposite the partial sever.

Abstract: A gapless order change in a continuous running corrugated paperboard web, created by using a partial transverse web sever upstream of the web selector device, utilizes selector fork orientation and operation that allows a redirected web portion to be diverted from one slider table to the other with no gap at the transverse slit. The improved apparatus is particularly effective in providing web transition at order change from the lower slider table to the upper slider table where the total width of the output web portions going to the upper level is increased and requires an upward diversion of a redirected web portion.

Abstract: An apparatus for preconditioning a medium web on a corragator before fluting the medium web during the manufacturing process of corrugated paperboard uses steam flows and pressures to press the medium web against a hot plate assembly. A plurality of elongated steam showers are located within a steam chamber secured to the preconditioning apparatus. The steam chamber wall structure includes a sealed web inlet and sealed web outlet for the medium web. The velocity and pressure (e.g., average steam pressure within steam chamber approximately 0.1 to 0.3 psi) of steam injected into the steam chamber holds the medium web against hot plates to promote heat transfer from the hot plates to the medium web. In addition, the medium web is heated directly by the latent heat of steam condensation, and also moistened directly by the condensation of the steam. A vacuum may or may not be used to increase the pressure of the medium web against the hot plates.

Abstract: Shingling of paperboard sheets cut from a web with a helical blade cutoff knife utilizes the downward deflection of the trailing edge of the cut sheet and simultaneous lifting of the leading edge of the web to position the sheets for shingling immediately downstream of the knife. A vacuum outfeed conveyor takes advantage of the initial downward deflection of the sheet caused by cutting to pull the trailing edge of the sheet onto the vacuum conveyor which is simultaneously slowed relative to the lead edge of the advancing web. In the preferred embodiment, vacuum is continuously applied and the conveyor is accelerated back to line speed as soon as the leading end of the web is pulled onto the vacuum conveyor.

Abstract: A corrugator double backer includes a web holddown apparatus that provides both heat and a holddown force to the upper surface of the paperboard web to maintain the web in intimate drying contact with the lower heating units without the use of a conventional driven holddown belt. A heated holddown mat which is longitudinally and laterally flexible is provided by a series of generally parallel, somewhat flexible, closely spaced heating tubes which are suspended above the web in the heating section in catenary fashion in the direction of web travel. Lift devices on one or both ends of the mat of tubes can vary the amount of mat contact with the web and, therefore, the heat and load imposed on the web. The tubes are steam heated and have flat low friction, high wear resistant lower surfaces which lie directly atop the corrugated paperboard web running thereunder.

Abstract: A synchronized flute double wall corrugated paperboard web is produced in a corrugating apparatus utilizing cooperatively operated single facers to provide an intermediate single face web with corrugated media on both faces, and then combining outer liners to both corrugated media immediately prior to on entry into the double backer utilizing a glue applicator that precludes glue line disturbance. The system may also be operated to produce conventional double wall board or single wall board utilizing either of the single facers. A synchronized flute double wall board provides enhanced strength and may be run on this corrugator at the same speed as single wall board.

Abstract: A rotary steam heated roll of the type having a series of circumferentially spaced, generally parallel and axially extending condensate channels or open-ended steam tubes in the cylindrical outer wall, includes at least one condensate removal pump associated with a channel or steam tube to positively pump condensate which rims at high speed radially inward to the center of the roll for discharge. A preferred embodiment includes a plurality of small piston pumps driven in response to roll rotation and timed to provide sequential circumferential operation.

Abstract: A rotary knife incorporates the use of an electronically controlled, tuned mass active damping system to control vibrations of the knife cylinder. The system preferably uses one or more electromagnetic actuators to provide force on a tuned mass which is mechanically coupled to the knife cylinder. Vibration sensors, preferably accelerometers, are used to monitor vibrations of the respective knife cylinders and tuned masses. A digital signal processor implementing a state space control system controls the electromagnetic actuators to remove vibration energy from the system. An active damping system in accordance with the invention is more effective in removing vibration energy than passive systems, especially in heavy-duty applications.

Abstract: A rotary steam joint and valve assembly for a steam heated roll includes a non-rotatable, axially slidable sleeve journaled on one of the roll shaft ends and operable to selectively withdraw condensate which pools in the lower part of the roll when the roll is stopped or operating at low speed. At higher roll speeds, when condensate is more uniformly distributed circumferentially around the roll interior, the valve is operable to open all radial condensate return paths to the concentrate discharge port in the shaft end. Steam is supplied radially to the shaft end and the valve is constructed to permit steam flow in either position of the valve.

Abstract: Certain parameters in a high speed order change in a corrugator, including a small gap between orders and the relative lengths of the old and new order sheets, require altered order change and discharge routines on the downstacker conveyor system in order to prevent edge butt between the last sheet of the old order and the first sheet of the new order. Alternate order change and order discharge routines, which are automatically implemented by the downstacker system controller, include accelerated movement of the old order shingle out of the downstacker vacuum conveyor to outrun the incoming first sheet of the new order or, alternately, allowing the first sheet of the new order to overrun the tail end of the old order and utilizing, if necessary, a device to divert the lead edge of the first new order sheet upwardly to allow the shingle to be reestablished.

Abstract: A large diameter and axially long cylindrical roll is fabricated from axially short cylindrical roll sections to provide a roll with circumferentially spaced, parallel and axially extending steam passages through the outer cylindrical wall of the roll. Through bore portions, which are gun drilled in the short roll sections, are aligned with cylindrical pins that also provide backing material for the annular welds used to join the roll sections. By utilizing pins of weld backing material in the bore portions, the bores may be formed very close to the outer cylindrical surface of the roll, thereby enhancing heat transfer in the completed roll.

Abstract: The labyrinth path in the corrugating nip of a single facer is substantially reduced by utilizing a small diameter corrugating roll captured between a larger diameter conventional corrugating roll and a backing roll arrangement. The smaller diameter corrugating roll is captured to prevent bending thereof under corrugating loads. The corrugator may be operated at high speeds without the adverse increase in labyrinth path and web tension characteristic of a pair of large diameter corrugating rolls.

Abstract: A heated cylindrical roll for handling and treating a running web of material has a laminated construction in which a series of thin circular rings, each in turn formed from a plurality of flat ring segments, are joined face-to-face to form a hollow cylindrical roll. The segments from which the circular rings are formed may comprise identical stampings and may be machined or otherwise formed prior to assembly to include an outer tooth pattern to provide a fluted roll surface for corrugating, apertures extending between the faces of the segments to define axial fluid supply passages in the assembled roll, radial slots to define vacuum passages in the assembled roll, and/or outer peripheral slots to define vacuum distribution slots in the surface of the assembled roll. The laminated roll is particularly adapted to utilize a novel steam supply and condensate return system.

Abstract: Flexible edge sealing membranes cooperate with the heating surface of a vacuum preheater and a web moving over the surface (1) to minimize air loss in the portions of the heating surface not covered by the web, (2) to prevent differential heating of the edges of the web induced by unrestricted air flow, and (3) to provide reduced friction contact with the edge portions of the web.

Abstract: A method and apparatus for manufacturing recyclable paper pallets utilizes spool-shaped laminated supports which are wound on a spool-shaped mandrel utilizing adhesive coated paper strips. In one aspect of the invention, the spool-shaped laminated supports can be glued to conventional upper and lower pallet skin sheets also made of paper material, such as corrugated paperboard. In another aspect of the invention, the spool-shaped pallet supports are utilized in a system in which the pallet is integrated directly into a pre-strapped load. In this system, a slip sheet is strapped directly to the bottom of a load and the slip sheet is glued directly to the upper faces of an array of pallet supports, sufficient to support the load and to provide the spacers or standoffs for subsequent insertion of lifting equipment, such as a lifting fork, beneath the load. The inherent rigidity of the strapped load may be sufficient to compensate for the lack of rigidity of the thin paper slip sheet.