Abstract: A manufacturing method of a piston in used for an internal combustion engine. The method comprises a step of reinforcing a circumference of a top ring groove by an inorganic fiber assembly, a step of forming an oil cooking gallery by a soluble core, a step of fixing the soluble core by projections formed in a strut preventing a thermal expansion of the piston, a step of setting the soluble core in a position supported by a punch mold, and step of setting the inorganic fiber assembly in an annular groove of a lower mold.

Abstract: Bonding pressure is uniformly applied to the lay-up (70) of a bonded product (10) by the disposition of flexible, compressible, perforated sheet material (85) between the lay-up and a pair of molds (75 and 80) during the manufacture of the product by diffusion bonding.

Abstract: The present disclosure relates to an apparatus and a method for deforming sheet metal plates and more particularly aluminium and steel plates. The objectives of this disclosure are realized by laminating a plate of sheet metal in juxtaposed and parallel strips. This method allows for the formation of spherical surfaces having a variable curvature. These strips are oriented according to predetermined axes according to the expected result.

Abstract: A method of manufacturing an air permeable electrocast shell comprising forming a conductive layer on the surface of a model, placing a layer of elutable particles into close contact with the surface of the conductive layer and effecting an electrocasting treatment to deposit metal between the conductive layer and the particles, except for the points of contact between the conductive layer and the particles, and between adjoining particles. The deposit of the metal is controlled so that the thickness of the electrocast shell is less than that of the particle layer. Thereafter, the particles are eluted from the electrocast shell to form innumberable fine vent holes which open at both surfaces of the electrocast shell.

Abstract: In a method for producing a clad plate by rolling an improvement comprises: a base material, a cladding material, and a cover material overlaid one on another to form a multi-layer structure, and after cleaning joining surfaces of the materials, the cover material is welded to the base material along the periphery thereof, thereby sealing and fixing the cladding material between the cover material and base material, and forming a multi-layer assembly. A member for preventing warp is overlaid over an outer surface of the cover material via a separating agent, and the member for preventing warp and the base material are fixed to one another by welding along the periphery thereof, thereby forming a blank for rolling. The blank is hot-rolled, a rolled article is cut along its periphery to separate the means for preventing warp, and subsequently, the cover material is removed by machining, grinding, or pickling.

Abstract: Welding muffs for joining thermoplastic pipes are molded using a core in which are placed terminals supported by plastic posts which may be removable and/or frangible so that when the cores are withdrawn the plastic posts do not prevent withdrawal.

Abstract: An improved heat exchanger is shown for indirect heat exchange between two fluid media. The heat exchanger has thin metallic walls and a multitude of convoluted or tortuous shaped internal flow passages to increase the effective contact time during which heat is transferred between the media. The heat exchanger is particularly suitable for heat exchange between fluids having low differential temperatures or specific heats, due to the thin wall structure, the elongated tortuous internal flow path created by the core structure and the absence of welds, soldering or other thick areas which tend to inhibit heat transfer due to their relatively greater mass. The heat exchanger is produced by a novel technique. A support matrix is assembled from a plurality of low melting point forms, each of which has angled internal passages. The passages of each form are positioned in register with the passages of adjacent forms.

Abstract: A laminated amorphous-metal transformer core having four sides joined by corner regions includes (a) joints located in a joint region in one of its sides and (b) side portions between the joint region and two corner regions. After annealing the core and while restraining the core laminations in a core region remote from the joint region, the joints are separated by displacing each of the side portions into a position of approximate alignment with the side of the core interconnected therewith at a corner region. Then a splint is applied to each of the side portions and the aligned interconnected side, thus holding these two parts in approximately aligned relation. The splint is relied upon to facilitate insertion of the aligned parts into the window of a coil, following which the splint is slid off the aligned parts, and core-lacing is completed.

Abstract: A base board having a plurality of semicircular through-holes filled with solder at side walls produced by filling through-holes with solder can be connected electrically to printed circuit boards with large connecting strength and high reliability.

Abstract: A proceses is disclosed for use in the manufacture of a color cathode ray tube having a rectangular flat faceplate. The process comprises positioning the faceplate in a predetermined x-y plane by referencing faceplate a-b-c reference areas on two adjacent edges or sides of the faceplate with complementary a-b-c reference points on a faceplate locating fixture; the fixture also has three spaced six-point precision indexing means. With the faceplate a-b-c reference areas and the faceplate locating fixture a-b-c points mutually referenced, six-point precision indexing means are attached to the faceplate in registation with the precision indexing means on the faceplate locating fixture. Using the precision indexing means attached to the faceplate, a shadow mask is registered with the faceplate through the use of complementary precision indexing means to provide a faceplate-shadow mask assembly in mutual precise registry.

Abstract: A method of manufacturing the adapter of a multipole slab includes assembling simultaneously a stack of alternating plates of magnetic steel and non-magnetic steel, a solder and a thin-wall steel container of which the walls sealingly enclose the stack of the plates and the solder. Then the container with the stacked plates and solder therein is heated to a soldering temperature, and subsequently cooled. Then the walls of the container adjoining the edges of the stacked plates are removed.

Abstract: The invention provides a method of manufacturing a hollow metal light conductor in which at least one metal layer is provided on a core of a synthetic resin material, for example, polymethylmethacrylate, after which the core is removed, and a metal tube is formed. The core is preferably removed by slightly elongating the core so that the cross-section is reduced, after which the metal light conductor can be pulled from the core. The reflecting metal layer on the inside surface of the light conductor preferably is of aluminium. The invention provides a hollow metal light conductor, for example, for use in an optical spectrometer, which is also suitable in particular to be used for light having a short wavelength, to less than 200 nm.

Abstract: A tripod universal joint includes a shaft with a forked end or tulip which is held in assembled relationship with a tripod spider by a spring clip having angularly spaced legs adapted to snap releasably into grooves in the tulip. The spider is located in a cup-shaped housing. To facilitate assembly of the tulip with the spider, a resiliently flexible washer is placed on the bottom of the housing and holds the spring clip upwardly in a position permitting the legs of the clip to interlock with the tulip when the tulip is moved axially toward the clip. After assembly of the tulip with the clip has been completed, the spacer washer is removed from the housing by pulling on a flexible retrieval wire which is attached to the washer.

Abstract: A pneumatic jack comprising flat sheets of an elastomeric material with no cords therein peripherally held in place by rigid framing members. The jack also includes a valve for communicating with the interior of the sheets. A source of aeroform fluid is utilized for inflating the jack to an enlarged shape to lift a car sufficiently for changing a tire.

Abstract: A method for manufacturing bladed disks, or blisks, for turbines by press welding of blades or outer airfoil elements to blade stives or inner airfoil elements on a disk is characterized by the provision on the outer and inner airfoil elements of flanges of excess flash material having alignment holes for dowel pins that assure alignment of leading and trailing edges of the airfoil elements during pressure welding, followed by removal of the excess flash material and the included dowel pins.

Abstract: Disclosed is a method of manufacturing a semiconductor device which comprises the step of forming grooves in the form of a grid on the upper surface of a semiconductor wafer formed with elements, the step of grinding or polishing the underside of the semiconductor wafer to thereby reduce the thickness thereof, the step of applying a first single-sided, self-adhesive sheet onto the underside of the semiconductor wafer, and the step of stretching the second single-sided, self-adhesive sheet so as to space out each other a multiplicity of semiconductor chips divided along the gridlike grooves of the semiconductor wafer. Each semiconductor chip is picked up and mounted on a lead frame.

Abstract: A cutter subassembly for a concrete planing machine which is comprised of an elongated acrylic plastic tube on which is manually assembled a set of circular multitoothed cutting elements and annular spacers arranged in a predetermined order to provide a desired cutting configuration along a linear axis. The cutting elements and spacers are assembled in a jig which additionally permits the attachment of a retaining clip at each end for holding the cutting elements and spacers in a fixed position on the tube. A plurality of completed cutter subassemblies are mounted on the cutter shafts of a drum assembly of the planing machine. Upon rotation of the drum assembly, the acrylic tube of each cutter subassembly disintegrates, providing the needed relative radial movement or play between the cutting elements and the cutter shaft during a planing operation.

Abstract: A method of sculpting in metal is disclosed in which the artist first sculpts or otherwise forms a core in a desired, artistic, aesthetically pleasing shape. The core is formed of a material which is at least meltable, and in most instances capable of being completely destroyed, as for example by being burned. In carrying out the process, the artist applies pin-like elements to the entire surface of the core, having large flattened heads flush with the core surface and at some locations, from one another. Thereafter, a brazing rod is applied to the heads of the nails, using conventional welding methods, forming a metallic sheath that follows the surface of the sculptured core and which is formed throughout with irregularly shaped openings occurring between the heads of the pin elements. The core is then burned out or otherwise destroyed without affecting the metallic sheath, leaving the hollow metallic sheath as the end sculpture.

Abstract: A process for manufacturing a piston ring includes the step of forming a gap seal from an elongated member on one side and an "L-shape" on the other side; compressing the ring to close the gap seal and move the two ends into a nesting position; welding a wire across the outside surface of the ring to hold it in that compressed condition; placing a plurality of such compressed rings onto a mandrel; and tightly clamping them in axially aligned positions. The surfaces of the clamped rings are then ground into a cylindrical surface which simultaneously removes the wire and the weld. The nested ends including the elongated member and the "L-shaped" member nest together when compressed into a cylinder.

Abstract: Process for the hot forming of sheets (5) made of a material that is difficult to work, especially of a dispersion-hardened high-temperature alloy by hot-isostatic pressing in one operation against the contour of a mold (1) serving as negative form in a container (2) that is under vacuum (6) and closed by a cover (3) with welding seam (4). In addition, joining of several sheets (5) to form one body (9) of complicated shape by the diffusion bonding process at the end of the hot-isostatic pressing in one heat in the same single operation.

Abstract: A method for manufacturing a disc-shaped curved magnet coil, particularly for a system for accelerating and/or storing electrically charged particles such as electrons. The conductors of the coil to be made are to be arranged around a winding core having a convex outside and a concave inside and are then to be fixed in position around the winding core. A coil form or fitting piece of predetermined shape is first added to a winding core, so that a provisional winding body with only positive radii of curvature on its outsides is formed. The conductors are wound under tension around the winding body and subsequently are fastened only to the winding core of the winding body and, after the coil form is removed, the thus exposed conductor portions facing the region of the concave inside of the winding core are pressed against this inside and fixed in position.

Abstract: A slotted retaining plate for use in a tubular reactor within an analytical system. The reactor contains inert packed material which provides for the necessary flow path length for a fluid stream entering the reactor. The retaining plate is extremely thin and has an array of slots which permit the necessary flow of the stream through the reactor, but retain the packing material within the reactor. The design of the slot array in the retaining plates essentially eliminates any possible impediment to the stream flow. The slots are adjustable to provide more flexibility in slot size control to allow use of smaller packing particles within the reactor and improve the instrument resolution in, for example, an amino acid analyzer.

Abstract: A method of lining the hot face of the wall of a heated enclosure, such as a furnace, boiler or the like, comprising the steps of compressing a plurality of substantially cylindrical modules of ceramic fiber material inwardly from the perimeter thereof; attaching the individual, compressed modules to the hot face of the wall in predetermined relationship whereby to define certain openings therebetween, inspecting the attaching means by virtue of the access thereto provided by the openings; filling the openings with a plug of ceramic fiber material; and then releasing the compression upon the modules to permit radial expansion thereof in all directions whereby to create a lining over the entire wall.

Abstract: For a molten metal stirring lance a steel tubular member is coated interiorly with wax, for instance, and a refractory material plug is cast in the member. The plug extends from one end of the member and leaves a clear space near the other end. Melting the wax out leaves a thin gas passageway gap around the plug. The end having the clear space is capped and connected to a gas feed pipe which is surrounded by a stiffener member. The latter member is convered with a refractory material protective sheath. The refractory material in the tubular member erodes or ablates by a small amount during each use in molten metal to keep the gas discharge gap clear.

Abstract: An improved method for coating multi-piece explosion-proof housings with a corrosion-resistant material which permits assembly and disassembly without interference with the corrosion-proofing function of the coating is disclosed. The method features assembly of the portions of the housing together with spacer means and dipping or otherwise coating the housing portions with a corrosion-resistant material. The spacer is formed in order to cause seal members to be formed directly in the coating which are brought into compression with one another upon subsequent assembly of the housing without the spacer so that an effective seal is provided.

Abstract: Improvements in means of and methods for mounting grips (hand grips, for example) on handlebars of bicycles and motorcycles; improvements in means of and methods for mounting resilient sleeves on shafts, pipes, rods and the like; inserting a plastic sleeve or strip into a resilient sleeve or handgrip, such operable to serve as a sliding, low friction surface with respect to a handlebar, shaft, pipe, rod or the like as the resilient sleeve or handgrip is mounted thereon.

Abstract: A double wall tank for the storage of liquids is manufactured from a rigid, cylindrical single wall inner tank by applying a primary spacing material to at least a portion of the exterior surface of the inner tank, applying over that inner tank exterior surface and primary spacing material a substantially rigid outer sheath of material, forming an opening through that sheath extending the full length of the sheath, introducing the secondary spacing material between the sheath and the inner tank exterior surface, and closing the sheath opening. This method provides a double wall storage tank in which at least a portion of the liquid-tight outer sheath is spaced from the inner tank.

Abstract: An apparatus for use in the manufacture of brush seals which comprise a plurality of filaments of brush material sandwiched between two sideplates. The apparatus comprises a workplate onto which is mounted one of the sideplates of the seal. A plurality of first clamping members clamp against the sideplate. Each member can be lifted to enable a tuft of brush material to be inserted and clamped against the sideplate. To enable more than one layer of tufts to be built up on the sideplate a second clamping means is provided to enable the first clamping members to be released. An indexing mechanism allows the first clamping members to be moved relative to the clamped tufts and when the assembly of tufts is complete a second sideplate is clamped onto the tufts and first sideplate. The apparatus also includes means for cutting a prewound ribbon of adhesively bonded wires into short lengths to form the tufts.

Abstract: A process for the production of laminated capacitors constituted by a stack of dielectric layers separated by metallic foils or plates, those of the even and uneven rows being respectively interconnected by lateral electrical connections. A plurality of juxtaposed master capacitors is produced on a large diameter wheel and a common intercalated layer is used between two successive stacks of master capacitors. The separation of the master capacitor stacks takes place after metal spraying 1 of the lateral edges of the group, so as to maintain the equilibrium thereof and permit the metal spraying of the other lateral edge prior to the separation of the master capacitors and optional cutting up into individual capacitors.

Abstract: The method of making a print head of the type that includes a piezoelectric transducer positioned within a metal housing having an annular channel in its inner surface that is sealed by a thin metal diaphragm to form an annular ink chamber. The transducer is in mechanical engagement with the inner surface of the diaphragm. The sudden removal of a voltage applied to the transducer expands the disk to reduce the volume of the ink chamber, rupture the meniscus, and force a droplet of ink from the printing orifice.The housing is formed with an internal taper which permits a groove to be cut readily either by a casting or by a tool entering from the larger end of the central opening in the housing. An aluminum mandrel is tapered to match the taper on the inner surface of the housing and provided with an annular groove that corresponds to the groove in the housing. The mandrel is plated with nickel that will later form the diaphragm. The housing and mandrel are then plated with indium.

Abstract: It is known to apply coatings which have desired characteristics, e.g., wear resistance, thermal barrier capabilities anti-oxidation, to articles the material of which does not have the desired characteristic, wherein the coating is applied directly to the article. Some article materials, e.g. titanium are highly reactive which immediately obviates several known methods of applying coatings. The invention uses a member (12) which would normally be preformed to mate with the article surface to be coated. The member (12) is manufactured from cheap, non-reactive material, as a base to which the coating (14) is applied by the most suitable of any of the known means. The member (12) is then placed against the article with the coating (14) therebetween and the whole hot isostatically pressed. The member (12) is afterwards removed, e.g. by machining or etching.

Abstract: An apparatus and method for rolling metal matrix composite material is disclosed. The material is confined within an aperture in a frame member during the rolling process. The frame member has deformation properties compatible with that of the metal matrix composite material permitting the frame member to be deformed during the rolling process and allowing the surfaces defining the aperture in the frame member to constrain the material during this process, thus eliminating edge cracking of the material. The frame member may be interposed between a top member and a bottom member both having deformation properties compatible with that of the metal matrix composite material so as to "encapsulate" the material during the rolling process.

Abstract: A capacitive acoustic transducer comprises a first field plate mounted to a semiconductor substrate structure, a second metal field plate having first and second oppositely and substantially exposed surfaces, and a mounting arrangement for mounting the second field plate to the semiconductor substrate structure so that the first and second field plates form an acoustically responsive capacitor, the first exposed surface of the second field plate substantially facing the first field plate, the mounting arrangement allowing the second field plate to respond to acoustic energy for altering the capacitance between the first and second field plates, the mounting arrangement including first and second contacts for respective connection to the first and second field plates.

Abstract: A regenerative-type thermal-storage heat exchanger having a thermal regenerator matrix formed by a plurality of radially spaced coaxial coils of solid cross-section thermal material surrounding a core. The matrix is formed from woven structures, each structure consisting of a plurality of longitudinal thermal members, a plurality of transverse cords woven through the thermal members and means for maintaining the thermal members in alignment during fabrication of the matrix. The matrix is formed by spirally winding the woven structure around a mandrel. After winding, the wound structure is inserted in a regenerator housing and the alignment maintaining means is then removed.

Abstract: A method for manufacturing a porous thin foil at least comprising a process for folding a first metallic plate having a large elongation percentage in half and putting a second metallic plate having a small elongation percentage between the folds of the folded first metallic plate, a process for cold-rolling a laminate of the folded first metallic plate and the second metallic plate put between the folds of the folded first metallic plate, and a process for separating a porous thin foil formed from the second metallic plate from the first metallic plate.The porous thin foil thus formed has numerous elongate fissures extending perpendicular to the direction of rolling, and hence the porous thin foil has a fibrous construction.

Abstract: Methods for manufacturing components having internal flow passages in which an insert composed of a carrier and passage-forming and/or flow controlling elements is sandwiched between or installed in elements of the component. The insert associated and component elements are then bonded together and the carrier subsequently leached away to complete the formation of the flow passages.

Abstract: In a method and apparatus for the height adjustment and installation of a slidable and/or raising, rigid roof member, to be built into a roof opening of an automobile roof, which roof member, after its height adjustment, is screwed to elements of the roof construction which do not participate in the height adjustment movement, a rapid and reliable height adjustment and installation are achieved in that, first the actuating elements are moved into the closed position, whereupon the roof member is inserted, by means of an installation template engaging over the roof opening and to be positioned onto the automobile roof, into the roof opening in a defined position with pressing of the roof member front edge onto the associated roof opening edge and simultaneous height adjustment, whereafter finally the screwing of the roof member in this position takes place.

Abstract: The disclosure relates to a process for the fabrication of low cost dual property turbine rotors having blades that are diffusion bonded to a blade ring that is simultaneously diffusion bonded to a central hub.

Abstract: A method for forming small-orifices 20 in the face plate 10 of an injector 12, especially a liquid propellant injector for a rocket engine. A stainless steel base plate is given a first layer 28 of electrodeposited Ni and fuel feed passages 24 and 26, respectively, are formed therethrough for fuel and oxidizer transfer. The feed passages 24 and 36 are filled with wax and silver is worked into the surface of the wax to permit electrodeposition of face plate 10. Connecting bores 42 to the perforations are made through the face plate nickel layer 40. Plastic mandrels 44 are fabricated, having legs 46 with support sections 48 and orifice-forming sections 50 and coupling tabs 54 for tying the legs 46 together. The support legs 48 of the mandrels 44 are inserted in the connecting bores for support and another layer 60 of Ni is electrodeposited to enclose the orifice-forming sections 50 of the mandrel legs 46.

Abstract: A method of producing rocket combustors wherein in forming an outer cylin by a powder metallurgical method on the outer side of a cylinder provided on its outer periphery with a cooling wall of channel construction having a plurality of grooves, a low-melting alloy is used as a filler to be filled into the grooves. It is also possible to form the outer cylinder after forming a Cu plating shell on the periphery of the inner cylinder filled with the low-melting alloy.

Abstract: An improved method of making an airfoil includes stacking plies in two groups. A separator ply is positioned between the two groups of plies. The groups of plies and the separator ply are interconnected to form an airfoil blank. The airfoil blank is shaped, by forging or other methods, to have a desired configuration. The material of the separator ply is then dissolved or otherwise removed from between the two sections of the airfoil blank to provide access to the interior of the airfoil blank. Material is removed from inner sides of the two separated sections to form core receiving cavities. After cores have been placed in the cavities, the two sections of the airfoil blank are interconnected and the shaping of the airfoil is completed. The cores are subsequently removed from the completed airfoil.

Abstract: A method of producing rocket combustors wherein in forming an outer cylin by a powder metallurgical method on the outer side of a cylinder provided on its outer periphery with a cooling wall of channel construction having a plurality of grooves (14), an Ni electroforming layer is formed on the outer side of the outer cylinder, and also a method of producing rocket combustors wherein an outer cylinder is of multilayer construction having two or more layers.

Abstract: A fluid-cooled article, such as a turbomachinery blading member, is provided with a fluid passage by a method of depositing a first material on a work surface of a mandrel by low pressure plasma deposition. A first member thus generated is separated from the mandrel. In one form, an inner surface of the first member is provided with a surface groove. After depositing a sacrificial material in the groove, a cover material is applied to entrap the sacrificial material. Removal of the sacrificial material provides the fluid passage.

Abstract: A method for the in situ repair of heat exchanger tubes in major heat exchanger equipment is disclosed in which supercooled sleeves are inserted into cracked heat exchanger tubes and are expansion-fitted firmly against the inner walls of the cracked tubes. In order to prevent premature expansion of the relatively long, small diameter sleeves during insertion, the tubes may be filled with a heat sink material which is removed following insertion. The insertion is also preferably accomplished very rapidly by means of a power-actuated ram which maintains the sleeve at its low temperature until the very last moment before insertion. Various guide means and plug means for the sleeve are described. The technology is also indicated as being applicable to the temporary sealing of defective tubes by using a removable plug in the form of a closed-end sleeve into whose interior a cryogenic agent can be selectively introduced during insertion and removal.

Abstract: A process for manufacturing ball joints or other self-lubricated joints, comprising placing the inner ring of the ball joint in a heat-retractable sheath of determined thickness and shrinking the sheath on this inner ring. The inner ring is then disposed in an outer ring blank which is then deformed so that the sheath is clamped between the outer and the inner ring. After machining of the blank, the assembly is treated so as to eliminate the heat-retractable sheath and thus form between the two rings a free space whose thickness corresponds to that of the sheath. A self-lubricating resin is then injected in this space.

Abstract: The invention relates to a method and an apparatus for the manufacture of heat exchanger elements. A pair of strips of weldable material e.g. high-grade steel is welded together in such a way that on both sides a longitudinally extending weld seam is formed, said pair of strips between said longitudinally extending weld seam defining a longitudinal channel which extends parallel to the weld seams and which serves for the conduction of heating or cooling agents. At least one of the strips is first provided with at least one longitudinally extending groove and is longitudinally welded to the other strip of the pair of strips in such a way that the groove forms with the part of the other strip covering it a longitudinal channel. A liquid filler material is poured into the longitudinal channel and solidified by cooling to below its freezing point.

Abstract: A method of forming cooling ducts in the windings of a liquid cooled electrical transformer without adding permanent duct formers to the winding, and without requiring an additional manufacturing step to remove duct formers. Plastic tubes dissolvable in the liquid dielectric are utilized as the duct formers. Thermal siphon flow of the liquid through the tube openings when the transformer is energized dissolves the tubes and enlarges the cooling ducts to the outside dimensions of the tubes.

Abstract: In order to permit a motor-compressor unit to be connected with the coolant circuit of a cooling device without interference from the walls of a compartment provided in the cooling device for housing the motor-compressor unit and to secure the motor-compressor unit in the compartment, the motor-compressor unit is placed at least partially outside the compartment and is pushed into the compartment and secured therein only after its coolant conduits have been connected with the coolant circuit and the electrical connections have been made. For this purpose, a mounting plate is temporarily installed in the compartment and the motor-compressor unit is loosely placed on it. After the connections have been made, the motor-compressor unit is pushed into the compartment on the mounting plate and then the mounting plate is removed. The tongues on rails secured to the motor-compressor unit are then screwed into the housing of the cooling device at the entrance to the compartment.

Abstract: Process for manufacturing a forged article in which a preform is generated by filling a semi-rigid liner with powdered metal, providing the liner with a sealing element, and isostactically compressing the liner and its contents. The liner is then removed from the green preform, the preform is sintered, and the resulting sintered preform is forged.

Abstract: Method of filling a casing with heat insulating fibers in which a fibrous heat insulating mass of fixed size is inserted into a space to be filled by vacuum-packing the fibrous mass in a vacuum-resistant bag, which may then be wrapped about an inner cylinder, introducing the bag into an outer cylinder and, after breaking the vacuum seal, allowing the fibrous mass to swell and fill any space within the outer cylinder not occupied by said inner cylinder, if any.