Abstract: A method and apparatus for manufacturing a corrugated product in which the corrugated mediums are bonded at their flute tips with no intervening liner. A corrugated belt or belts is provided to withdraw the bonded and aligned mediums in a substantially straight line from the pair of corrugating rolls which are synchronised to achieve the alignment and bonding of the flute tips of the two mediums. The corrugated belt provides support and constraint for the bonded mediums until the bond is set or until a liner sheet is bonded to one of the mediums.

Abstract: The known double facer of the type that when a single-faced cardboard sheet and a liner are being pinched and conveyed by a belt on the upper side and a heating box on the lower side, pressurized air is fed from an air chamber onto the back side of the belt to press the single-faced corrugated cardboard sheet and the liner onto the side of the heating box and thereby the single-faced corrugated cardboard sheet and the liner are made to stick to each other, is improved in that the side walls of the air chamber are supported in a movable manner in the widthwise direction of the sheet so that the width of the air chamber can be adjusted according to the width of the corrugated cardboard sheet to be produced to avoid the side edge portions of the corrugated cardboard sheet from crushing and insufficiently sticking. This results in reduction of unacceptable sheet products and economy of a driving power expense.

Abstract: An apparatus for making laminated dual and multiple arch corrugated structures including a first unit for making single-face corrugated members formed of a corrugated member and an attached liner and a second unit for combining one or more single-face corrugated structures into a double-face structure. The subject invention includes a novel mechanism for laminating one or more portions of the single-face or double-face corrugated structures and/or for impregnating one or more of the members of the such structures with an impregnating substance. The subject improvements also reside in a novel hold down roll construction to prevent wrinkling of the edge portions of web members used in the construction of corrugated panels.

Abstract: A double-facer unit includes an applicator roller having a cylindrical outer surface with spaced depressions distributed relatively uniformly over the surface thereof, mechanisms for maintaining corrugation ridges opposite from the liner side of the single-face web against an arcuate portion of the outer surface of the applicator roller for applying adhesive thereto, and an adhesive container having adhesive therein exposed to the cylindrical surface of the applicator roller in the double-facer unit whereby the adhesive contained in the container is transferred to the surface of the applicator roller including into the depressions therein, a device associated with the adhesive container for scraping excess adhesive from the roller but not from the depressions whereby the adhesive remaining in the depressions is transferred to the corrugation ridges on the single-face web when in contact therewith, and mechanisms for maintaining predetermined tension on the single-face web during the time the adhesive in the d

Abstract: Apparatus for applying adhesive onto flutes of single facers of corrugated media, so that the single facers may be adhered together and to a facing to form a composite web, comprises a plurality of adhesive applicator rolls, each for applying adhesive to the flutes of an associated one of the single facers. The actual speed of travel of the single facers passing across the applicator roll peripheries is sensed, and the rate of rotation of each roll is independently and accurately controlled, in accordance with the sensed speed, to apply a desired amount of adhesive onto selected areas of the flutes. The independent accurate control over applicator roll speeds enables minimum amounts of adhesive to be applied onto the flutes of the individual single spacers, as determined by their configurations and consistencies, while still ensuring proper adhesive of the single facers one to the other ad to the facing.

Abstract: A method of forming trim cover being one of elements constituting a seat which is used for furniture or as an automobile seat, comprises feeding an assembly of a sheet of covering material and wadding material, with the covering sheet side of the assembly turned upward, onto support means for receiving and supporting the assembly thereon. The support means has at least one hole of a desired predetermined shape. A portion of the assembly substantially positionally corresponding to at least one hole is pressed downwardly to cause a portion of the wadding material of the assembly positionally corresponding to the hole of the support means to be protruded downwardly from the support means through the hole of the support means. The protruded portion of the wading material of the assembly is cut, while the same portion of the assembly is still pressed downwardly. The assembly is advanced to a backing sheet laminating station.

Abstract: A single facer comprising a pair of upper and lower corrugating rolls having a corrugation thereon for corrugating a core sheet fed therebetween. The sheet is then pasted at the tops of their corrugations. A liner is fed in different direction and caused to pass together with the pasted sheet between the lower corrugating roll and a pressure roll to be sticked to each other to thereby form a single-sided corrugated sheet. The upper and lower corrugating rolls are supported by separate rotatable frames, and engageable with each other to form a corrugation forming unit. A plurality of corrugation rolls having a different corrugation shape thereon are provided on each of the rotatable frames.

Abstract: The invention is primarily concerned with a sandwich material (55) made of sheets based on paper. This material is substantially comprised of a sheet (42) of corrugated paper (44) forming one or several layers. An intermediate paper sheet (31) is bonded to the corrugations of the sheet 42. A film (29) of a thermoplastic compound adheres physically as the result of an extrusion to the outer side of the intermediate paper sheet (31).The process for manufacturing this material consists firstly in extruding a film (29) of thermoplastic compound on the intermediate paper sheet (31), and then in bonding the web (27) of protective layer thus obtained on the corrugations of the sheet of corrugated paper (42).The invention is remarkable in that these operations are carried out on a standard machine for manufacturing corrugated paperboard.

Abstract: In the fabrication of double-faced corrugated paperboard, the exposed flute tips of single-faced corrugated board are prepared with a coating of liquid adhesive to receive a second liner web. To press the flute tips uniformly against the adhesive film coated surface of a glue applicator roll, pressure is applied by a segmented air bearing wherein multiple air bearing shoe segments are resiliently secured to a common manifold air source.

Abstract: Apparatus for stacking of corrugated cardboard sheets on at least two stacks disposed adjacent each other in a stacker included in a corrugator, wherein a slitter scorer, first conveying means, cut-off means, second conveying means and a stacker are located each behind the other in conveying direction, characterized in that at least one applying means is located above the first conveying means, said applying means being supported for movement transverse to the conveying direction and said applying means being adapted to apply adhesive strips, self-adhering paper strips or the like to adjacent webs.

Abstract: A system is disclosed for the production of double-walled helically wound thermoplastic pipe. The apparatus includes an endless former (10) of the axially advancing and rotating type for forming a band of thermoplastic material (24) into a corrugated outer wall (26). An internal extruding device (28) extends along the core of the former and extrudes a second band (34) of thermoplastic material onto the interior of the outer wall. A cold shoe (36) presses the inner wall against the outer wall to form a smooth inner wall (42) of the double-walled pipe. It is also possible to provide for the insertion of a reinforcing profile in the corrugations of the outer wall.

Abstract: At a location between a single facer machine and a glue machine, a web of corrugated paperboard has the flutes crushed in a narrow zone longitudinally of the web. A bonding agent is applied only to the uncrushed flutes. Preprinted liners are applied to the bonding agent on the uncrushed flutes with the liners being spaced from one another by said narrow zone.

Abstract: A single facer including a main frame installed on a base for supporting a paste application roll, a pressure roll and so on, a movable frame fixed on or removably supported on the main frame for rotatably supporting upper and lower corrugated rolls in meshing engagement with each other, and a transfer mechanism for moving the movable frame in a transverse direction substantially in the axial direction of the respective upper and lower rolls to transfer them out of or into the main frame.

Abstract: Apparatus is disclosed for introducing a gas into a porous pack the apparatus comprising gas injection means for introducing a gas into the pack, a conveyor for moving the pack into superimposed position to the gas injection means and for deflecting the gas out of the pack between the gas injection means.

Abstract: Back pressure against a single-faced, corrugated web opposite of a flute tip glue applicator roll is provided by a transversely extending air bearing. Air bearing fluid flow is derived from an air distributor manifold that is secured for adjustable positionment relative to the web surface.

Abstract: A process for producing a strip (4) of corrugated cardboard by gluing one or more sheets (8, 10) of single-face corrugated cardboard and a sheet (6) of covering paper.At least the corrugations of the upper sheet (10) are heated by means of an infra-red radiation panel (40), after the glue has been deposited on them in the gluer (1) and before the sheets come in contact with one another in the double-face machine (2).

Abstract: A splicer is used in a corrugated cardboard production line. The splicer has a pair of pivotal levers having opposing jaws which open and close responsive to a pivoting of the levers. The faces of each of the jaws have a pair of pads for enabling a passage of a web of corrugated cardboard when the jaws are opened and for gripping the web when the jaws are closed. A guillotine blade is positioned between the pairs of jaw pads to grip the web when the jaws are closed. A pair of brake shoes are positioned downstream from the jaws for holding the web while the brake shoes are closed.

Abstract: A heating device for corrugated cardboard in a corrugated cardboard pasting machine, comprising several heating plates spaced in feeding direction and covering the maximum width of the corrugated cardboard strip while being adapted to be connected to a source of heat via a control device and against the upward facing heating surface of which the cardboard is guided under load by a weighting belt and/or compressed air, with two or more separate heating plates arranged side by side transversely of the direction of movement of the corrugated cardboard in at least one section and adapted to be separately heated by means of the control device.

Abstract: Device permitting the instantaneous changing of the width of application of glue to a web of paper in the manufacture of corrugated cardboard, the glue being applied to the web with the aid of a gluing cylinder (5) driven rotationally and dipping into a tank of glue over a width adjusted by two barriers which are movable in the tank. It includes a detachable auxiliary doctor device (1) comprising two doctors (2) to be applied momentarily to the two longitudinal ends of the gluing cylinder (5), on the non-immersed top part of the latter, the said doctor device being in addition equipped with a device for adjusting the distance (L3) left free for the passage of the glue between the two doctors.

Abstract: At a location between a single facer machine and a glue machine, a web of corrugated paperboard has the flutes crushed in a narrow zone longitudinally of the web. A bonding agent is applied only to the uncrushed flutes. Preprinted liners are applied to the bonding agent on the uncrushed flutes with the liners being spaced from one another by said narrow zone.

Abstract: Multiple ply corrugated or solid fibre paperboard having any desired number of plies is made by adding to the delivery end of conventional corrugator or paster apparatus, between the cut-off section and the stacker section, a glue applicator system controlled, preferably by computer program, to apply glue only to the desired areas of those outfeeding paperboard sheets which are to be bonded together to form the desired multiple ply paperboard. The glued and unglued paperboard sheets proceed to the stacker section where they are stacked one upon another. The paperboard sheets having an interface of glue are bonded together to form the multiple ply end product and the paperboard sheets having no glue interface allow subsequent separation of the plurality of multiple ply corrugated paperboard end products in the stack. Offsetter mechanism is provided to offset corresponding margins of certain plies of a group before depositing them in the stacker, to form a splice joint.

Abstract: Apparatus is disclosed for splicing together successive sections of single facer corrugated board having planar and corrugated fibrous layers, which sections are initially conveyed colinearly in spaced relation at uniform speed with the flutes extending in the direction of travel of the sections, characterized by the provision of a reciprocatory vacuum bar feed member operable initially to accelerate a subsequent section relative to a preceding section to a position in which a protruding layer portion at the trailing end of the preceding section is in superposed relation relative to a protruding layer portion at the leading end of the subsequent section, and subsequently to displace the section at the lower uniform speed at the moment at which the adjacent ends of the sections are in overlapping relation, whereupon the superposed portions may be bonded together to connect the sections to form a continuous web having longitudinally extending flutes.

Abstract: An apparatus and method is disclosed for attaching a continuously moving elastic ribbon to a continuously moving web such that only selected discrete areas of a finished conformable garment fabricated from the web are elasticized. The web is moved into engagement with a continuously moving first conveyor means having a plurality of spaced apart gaps in its surface and the first conveyor means travels along an inclined guide means toward a second conveyor means traveling opposite to and in the same direction as the first conveyor means. The second conveyor means carries a plurality of spaced apart web tucking means which are moved by the second conveyor means into registry with the gaps in the first conveyor means. As each of the web tuck means move in registry with the gaps, the web tuck means are inserted into the gaps to form tucks in the web due to the movement of the first conveyor means toward the second conveyor means.

Abstract: There is provided a single facer consisting of an upper roll, a lower roll, a pasting device and a pressure member in parallel with the lower roll for manufacturing single-faced corrugated board. The single facer is characterized by the provision of a suction conveyor having belts for conveying single-faced corrugated board, the suction conveyor being disposed at the side of another sheet in the transport passage of the single-faced corrugated board in the proximity of the engaging point between the lower roll and pressure member, thereby preventing the strip-off or separation of a contact portion between the corrugated sheet and another sheet by means of the structure, which is extremely simple and compact in form.

Abstract: A method and device for use in the method for forming a reinforcing filamental network is the subject of this application. The network includes a pair of straight filaments (54, 56) which can extend generally parallely with respect to one another and be spaced at a given distance. A serpentine filament (58) is made to sinuate across the straight filaments (54, 56), and can be bonded thereto at intersections by means of a hot melt adhesive which impregnates the filaments (54, 56, 58) and which has a measure of flow potential when subjected to pressure.The device for forming the network includes a cylindrical cam (100) which is disposed for rotation about an axis generally parallel to the axis of one of two pressure rollers (76, 90) which effect cold flow of the hot melt adhesive with which the filaments (54, 56, 58) are impregnated. The cam (100) has a groove (110) formed in its outer surface. A shoe (108) of a reciprocating filament guide (102) rides in the groove (110).

Abstract: Disclosed is an improved method of producing corrugated cardboards, in which water suspension of raw starch is used as an adhesive. The raw starch is, after application thereof, heated to form gell or paste with dry steam prepared by reheating low-pressure steam with high-pressure steam. Also, disclosed is an apparatus for practicing the improved method.

Abstract: A method and apparatus for the production of air cell cushioning dunnage material, for protective cushioning purposes in packaging or other purposes, with the air cell product possessing substantial strength, and the ability to retain its original thickness under load. The method and apparatus are such that the apparatus can be halted in its operation without injurious effects to the dunnage product being produced, and can be restarted to again commence production of the cushioning dunnage product. The apparatus and method utilize flexible thermoplastic sheets or film of material, to produce the air cell product, with the plastic sheets being preferably formed of a composite of an intermediate stratum of relatively high density high melting point plastic, and exterior stratums of relatively low density, low melting point thermoplastic bonded to the intermediate stratum. Various other embodiments of flexible air cell sheeting are also disclosed.

Abstract: An apparatus is disclosed for aligning at least two running webs with each other. It is characterized in that any lateral displacement is corrected at a position at a predetermined distance upstream of the displacement detection point or where excessive tension is not applied to the web to be corrected. Further, correction is made taking into consideration the time for the displacement detectors to follow the web movement and the time for the web to come back to a stable condition after splicing.

Abstract: A reinforced corrugated laminate and the method and apparatus for the manufacture thereof which includes forming a corrugated layer with reinforcing wire elements with at least certain of the wire elements being positioned normal to the corrugations and applying planar webs to one or both sides thereof by adhering them to the crest portions of the corrugated layer and combining the planar and corrugated structures with cushioning and resilent foam materials.

Abstract: Connection insulators having a plurality of insulating compartments for electrically isolating electrical connections formed from strips of insulating material of indeterminate length. In one embodiment, a first strip of insulating material is supplied to a securing station at a predetermined average rate of supply and a second strip of insulating material is supplied to a forming station at a predetermined average rate of supply greater than the predetermined average rate of supply of the first strip with the pliability of the second strip being enhanced by heating the strip for aiding the deformability characteristics of the second strip. The second strip of insulating material is deformed into predetermined patterns at the forming station and then moved into position adjacent to the first strip of insulating material at the securing station.

Abstract: Described is an apparatus for the application of a thin non-woven web of glass or mineral fibers onto corrugated sheet perpendicularly to the corrugation which comprises a rectangular frame open at the top and bottom and having parallel vertical walls, wherein the frame is provided with wheels and supported on rails above the sheet material which is supported by a matrix on working-level above the floor and coated with a layer of a solidifying glue. An applicator plate is mounted vertically movable in guideways at two opposite walls of the frame and adapted with its bottom edge to follow the corrugations of the sheet to bring the fibrous web into close contact with the glue-coated sheet. Because of the delicacy of the fibrous web of material, the lower end of the applicator plate which is adapted to press the web of material against the sheet, must be rounded.

Abstract: A reinforced laminate and the method and apparatus for the manufacture thereof which includes the embedding of reinforcing wire elements in plastic layers and plastic laminates to provide reinforced structures, producing a reinforced corrugated laminate including a corrugated layer with plastic layers applied to one or both sides thereof, producing a wire grid, corrugating the grid and applying overlying plastic layers and combining the planar and corrugated structures with cushioning and resilient foam materials.

Abstract: In a single-face corrugator of the type in which the corrugated paper is held by suction against the lower corrugated cylinder, the latter includes, outside its inner chamber filled with saturated heating vapor, separate longitudinal channels in the peripheral body of the cylinder. Each channel is connected to the exterior via axial channels and elongate grooves machined in the periphery of the cylinder, and can be connected to a suction apparatus via two hollow and sealed circular arcuate sectors bearing on the part of the face of the cylinder associated with the holding region on the latter. The grooves are staggered and machined in circumferential portions of the periphery of the cylinder so as to extend over several corrugations thereof. An additional blowing sector permits detachment of the corrugated paper.

Abstract: A humidifier arrangement for at least one web of travelling hydrophilic material is provided to distribute humidity in a pre-determined manner over the width of the web in order to correct a tendency to warping of a material formed by the connection of this web to a second web. The arrangement comprises a plurality of jets distributed transversely with respect to the direction of travel of the first web over a table and opposite to the path of at least one side of the latter. Means for individual regulation of the rate of flow of each jet is provided and comprise, for each jet, a slide for regulating the rate of flow through this jet. The various slides corresponding to the various jets are able to move longitudinally on the table so that the position of the slides on the table for a given regulation provides vizualization of the shape of the cross-section of the material which is to be corrected by this regulation.

Abstract: A method for producing corrugated board utilizes a glue applying means constructed with an elongated shoe floatingly mounted alongside of and urged toward a glue applicator roll by a fluid controlled biasing means. A longitudinally extending depression in the shoe is substantially closed by the glue roll to define a glue cavity to which glue is fed by a positive displacement pump. The shoe is mounted so that the downstream end of the shoe is movable away from the glue roll automatically as required to permit glue to exit from the cavity at the same rate it is supplied thereto. This provides what is effectively a self-adjusting nozzle or fluid distribution slot extending the full length of the shoe and through which glue is forced from the cavity to form a thin layer of uniform thickness on the outside of the glue roll. The latter applies such thin layer of glue directly to the flute tip of a corrugated web for joining a liner web to the corrugated web.

Abstract: In a single facer including an upper corrugating roll, a lower corrugating roll and a pressure roll, the lower corrugating roll is provided with a plurality of spaced circumferential grooves on the outer peripheral surface extending at right angles to the flutes of the corrugating roll. A plurality of circumferentially spaced bores are drilled in the roll extending in an axial direction and communicating with the bottoms of the aforementioned circumferential grooves. Suction means is disposed at one end surface of the roll for communicating with the bores. The suction means is selectively placed in communication with only those bores which at the time are in an angular position where a corrugated web is to be held in contact with the roll. In one preferred embodiment pressurized gas is placed in communication with selected bores to provide gas therethrough during the period when these selected bores are in an angular position where the corrugated web is to be released from the roll.

Abstract: Apparatus is provided for the production of a corrugated pasteboard having a cover coating on at least one side. The apparatus includes a toothed corrugating element, a toothed corrugating counter-element co-operating therewith, a glue applicator and a drying apparatus. At least one corrugating element is an endless element (2) which loops at least partially around the other element (1). In this manner the noise generation and roll wear are reduced, the quality of the corrugated cardboard is improved, the paper consumption and difficulties of adjustment of parts of the apparatus are reduced and the feed and introduction of the paper web are facilitated.

Abstract: A corrugator line includes a single facer and a double backer with a horizontal bridge extending between them. Instead of conducting the web from the single facer to the double backer as fan folds on a horizontal belt conveyor, a dancer type accumulator is positioned on the bridge between the single facer and the double backer and the web is looped back and forth between the accumulator stationary rollers and its movable dancer and the dancer is force loaded away from the stationary rollers so as to maintain substantially constant tension in the moving web. Provision is made for controlling the speed of the single facer or the double backer in response to excursions of the dancer from a reference position to allow the single face material to spend a uniform time between the single face and double back processes. Also, a steering assembly is positioned on the bridge to align the web from the single facer with the machine center line of the double backer.

Abstract: A method and apparatus for continuously forming a multi-ply corrugated container board from freshly laid web plies by simultaneously forming the separate plies from aqueous slurries of fibers on corresponding foraminous fabrics, and dewatering each of them sufficiently to form a web ply capable of being handled in a papermaking machine as an integral web. All of the webs are formed on a single papermaking machine, but separately. The first web ply is laid on a traveling forming wire, such as a fourdrinier wire, and each subsequent web ply is formed in close proximity to the traveling forming wire and brought into bonding engagement seriatim with the top surface of the previously formed web ply carried on the traveling forming wire.A typical corrugated box board has three plies with the inner ply being corrugated.

Abstract: An apparatus for detecting the correct timing of lot changing in a corrugator. The sum of a finished extent, which is the product of a specified cut length and the number of cut pieces excluding rejected cut pieces, and the residual quantity of a single-faced or double-faced corrugated board on the production line is subtracted from a lot size or length which is the product of the specified cut length and a specified number of cut pieces, to obtain a residual lot length, and this computation is successively performed at predetermined time intervals. The amount of raw material board fed is successively subtracted from the residual lot length, so that when the difference is reduced to zero, it is an indication of the desired lot changing timing.

Abstract: The present invention relates to a reinforced corrugated board which is specifically reinforced in only those locations where such reinforcing is required in the product produced from this board. The board has a smooth top face or liner and a first corrugated layer adhesively affixed therebeneath. To the bottom of the first corrugated layer, a second corrugated layer is affixed. This second layer is only as large as the area requiring special reinforcing in the final product and need not be as large as the first corrugated layer. A bottom liner or facing is affixed to the second corrugated layer and any of the first corrugated layer which extends around the second layer.An apparatus and method for producing this board sheet are also presented.

Abstract: A changeover system for a corrugator designed to halt the corrugator during the changeover to diminish paper loss. When the corrugator is halted, a traveling knife severs the combined webs adjacent the beginning of the steam table run. The slitter scorer and the cutoff are changed and the corrugator is restarted. The traveling knife which severs the combined webs may operate above the steam table or below the steam table; alternate forms may be used.

Abstract: This method is a method producing double-faced corrugated boards which includes methods for changing single-faced corrugated boards. The methods comprise the steps of cutting a single-faced corrugated board which is fed from a single facer onto a bridge and delivered from the bridge into a double facer at said bridge or before it; and splicing the tailing edge of the board with the leading edge of another single-faced corrugated board which is fed from another single facer onto said bridge.

Abstract: In a corrugating system, a supplemental means for insuring that the liner and corrugated medium are properly conditioned with adhesive or bonding material along the entirety of its length and width of the bondable surface as the machine is starting up following down time to avoid subsequent board delamination.

Abstract: An apparatus and method for providing permanent pipe sections in a foam-backed material that utilizes two rotating members which cooperate to form alternate ridges and valleys in the material after which the valley portions are bonded to a backing sheet so as to maintain the pipe sections in the material.

Abstract: A reinforced laminate and the method and apparatus for the manufacture thereof which includes the embedding of reinforcing wire elements in plastic layers and plastic laminates to provide reinforced structures, producing a reinforced corrugated laminate including a corrugated layer with plastic layers applied to one or both sides thereof, producing a wire grid, corrugating the grid and applying overlying plastic layers and combining the planar and corrugated structures with cushioning and resilient foam materials.

Abstract: Wire reinforced paper products wherein wires are affixed to a paper layer or included within a paper structure with at least one paper layer conforming to the contour of the wires to supplement the rigidity produced by the wires and a corrugated paper structure including wires disposed therein. The paper products are manufactured in continuous processes which enable the use of one or two sets of parallel wires, the latter producing a wire grid structure. In the manufacture of corrugated structures one or two sets of wires may be included in the corrugated portion and the overlying layer or layers and in so doing the structural strength and moisture resistant characteristics of the resultant corrugated board may be increased several fold without materially increasing the cost of the board as compared with board using relatively heavy paper in order to achieve increased strength.

Abstract: Each corrugating roll on a single facer machine is separately driven at substantially the same speed without the corrugating rolls being geared directly together and without transmitting driving torque through mating flutes on the rolls whereby the rolls may corrugate a web passing therebetween with minimal tension of the web.

Abstract: A polymer plastic coated paper double-facer corrugating machine equipped with web preheating cylinders having position adjustable wrap control arms is described having a variable response relationship between the machine production speed and a corresponding wrap control arm setting. The double facing nip of the machine is provided with a series coupled pneumatic loading spring and worm jack to set the nip clearance. For transitional support of double faced product between the load variable nip roll and the lower tractor belt of the double-faced board pulling section, an air table is provided.

Abstract: A continuous method of manufacturing a drainage system and apparatus therefore comprises a continuous assembly line which forms a plastic core material followed by continuously forming an envelope surrounding the formed plastic core and then sealing the stuffed envelope. In a preferred embodiment of the present invention, an extruder is used to transform granulated plastic material into sheet form. This plastic sheet is then fed directly into a plastic forming machine. The plastic forming machine will form a plurality of hills and valleys in the plastic sheet thereby defining a plastic core. Thereafter, continuous sheets of permeable fabric material are attached to the upper and lower surfaces of the formed core while the edges of the permeable fabric are secured to one another either by adhesive, sewing or any other suitable bonding method. Next, the draining system is either cut into desired lengths or rolled for shipping purposes.