Abstract: A post-tensioning apparatus and method including first and second body sections interconnected by an intermediate anchor head. Each body section has an end anchor head on an end opposite the intermediate anchor head and includes a tendon with a pair of strands adapted for being tensioned between the intermediate anchor head and the corresponding end anchor head of each body section. Each pair of strands is encapsulated between the intermediate anchor head and each corresponding end anchor head of each body section in a mechanically interlocked duct adapted to receive a bonding agent after tensioning of the strands. A passage is provided proximate the end anchor head of the first body section and provides a passage for insertion of bonding agent, preferably in the form of grout, into the duct of the first body section. Grout can be injected through the passage proximate the end anchor head of the first body section such that the grout can enter and fill the duct of the first body section.

Abstract: Parallel spaced grooves are cut within the surface of an existing reinforced concrete member in the direction of bending and at locations where existing tensile reinforcing is inadequate. Elongated reinforcing elements, such as composite rods with continuous carbon fibers, are positioned within the grooves, after a curable bonding material, such as an epoxy resin, is inserted into each groove so that the bonding material surrounds the reinforcing element. The material is formed flush with the surface and allowed to cure to bond each reinforcing element to the concrete defining the corresponding groove. The grooves and reinforcing elements extend within the top surface of a concrete slab across a beam or support for the slab, extend within the bottom surface of the slab at least fifty percent of the distance between adjacent supports for the slab, or within a vertical surface of a concrete or masonry wall or column.

Abstract: A method for manufacturing pre-stressed piezoelectric actuators using a pre-curved piece of ceramic is provided. An adhesive, preferably a polyimide, is disposed between a metal pre-stress metal layer and a pre-curved PZT ceramic. The entire composite structure is heated to a temperature above the melting point of the adhesive material and then subsequently cooled to allow the adhesive layer to set. As a result of the difference in thermal contraction rates of the materials, the pre-curved PZT ceramic is compressively stressed. This pre-stressing provides a piezoelectric actuator which is durable, and produces a higher displacement than a conventional piezoelectric actuator.

Abstract: A fiber bundle is wrapped with a tape by helically and entirely winding the tape around the bundle, while applying a constant longitudinal tension to the bundle; and thereafter unwinding and removing the tape from its last turn to gradually expose the bundle towards its basal end, while inserting the exposed portion of the bundle gradually into a cylindrical protector. The method keeps constant the outer diameter of the bundle by adjusting the tape tension, even if the bundles are composed of varied numbers of fibers in one protector, so that a wider use of the protector is realized. In the method, the wrapping operation does not produce any damaged fibers from which a fluid such as blood leaks in a hollow fiber apparatus, and no later adjustment is necessary for the wrapped bundles, thus improving the production efficiency.

Abstract: A method and means for attaching flexible, low density or compressible structure such as foam to injection molded parts, wherein a mold has a recess shaped for a corresponding flexible, low density or compressible structure. A valve plate made of injected material is placed against the foam structure to compress and protect the foam structure from molten injected material. The valve plate has through apertures for limited access of the injected material to predetermined surface portions of the foam. The molten injected material forms an adhesive between the foam structure and valve plate to adhere the foam structure to the valve plate, and the resultant final component assembly.

Abstract: A prestressed concrete tensioning system for a tensioning tendon in the construction of a prestressed concrete beam comprising an anchor seat and a prestressed tensioning device. The anchor seat embedded in one end of the beam and has spherical structure and inverse ratchet gripping device therein for adjustably holding one end of the tendon. The tensioning device has a hollow cylindrical housing including a hydraulic fluid chamber therein for slidably disposing a piston member in associated with a wedged surface grip means which are operated by hydraulic pressure for gripping and tensioning one end of the tendon, and a hemisphere concave in the forward end of the housing for engaging with the hemisphere convex of the anchor seat to obtain an universal joint effect. This disclosure is characterized in the prevention of shear and strength declination to the tendon and the risk to the ambient personnel.

Abstract: A composite structure and related fabrication method is provided which has a plurality of composite material layers and at least one embedded shape memory alloy component for providing controlled structural deformation. The shape memory alloy component includes a shape memory alloy tendon having a relaxed shape at temperatures below a predetermined transition temperature and a contracted shape at temperatures above the predetermined transition temperature. The shape memory alloy component also comprises a pair of electrically insulating opposing face sheets adhered to opposite sides of the shape memory alloy tendon to electrically isolate the shape memory alloy tendon from the surrounding composite material layers.

Abstract: A method and apparatus are shown for lining a tubular member with an elastomeric liner having an outside diameter which is initially greater than the inside diameter of the tubular member. A series of downsizing rollers reduce the outside diameter of the liner a preselected amount. A series of shaping rollers form the downsized liner into an ellipse, thereby allowing the downsized liner to be guided around bends and turns into the interior of the tubular member. After insertion, the liner is allowed to expand to substantially its original outside diameter to secure the liner within the tubular member.

Abstract: A method for forming ferroelectric wafers is provided. A prestress layer is placed on the desired mold. A ferroelectric wafer is placed on top of the prestress layer. The layers are heated and then cooled, causing the ferroelectric wafer to become prestressed. The prestress layer may include reinforcing material and the ferroelectric wafer may include electrodes or electrode layers may be placed on either side of the ferroelectric layer. Wafers produced using this method have greatly improved output motion.

Abstract: A hose assembly, an internally threaded member therefor and methods of making the same are provided, the hose assembly comprising a flexible hose having opposite ends, an internally threaded member mounted on one of the opposite ends in a manner to swivel thereon to permit the internally threaded member to be finger coupled to an externally threaded part of a liquid dispensing spigot, the internally threaded member having an outer peripheral surface, and an annular member disposed around the internally threaded member in a manner to engage the outer peripheral surface thereof and having an external peripheral surface to be finger engaged for turning the internally threaded member in unison therewith relative to the hose, the annular member comprising a SANTOPRENE material.

Abstract: A method of introducing a casting compound composed of aggregates and a matrix with a hardening binder into a hollow space within a tubular sheathing of a tension member composed of one or more individual elements, particularly in the anchoring range of the tension member relative to a structural component. In accordance with the method, the aggregates are introduced first and the matrix is then introduced in the liquid state into the grain structure formed by the aggregates. A finely granular material is used as the aggregate. The finely granular material is introduced with the aid of compressed air through at least one tubular lance which is inserted in longitudinal direction of the tension member through the anchoring range.

Abstract: Pre-stressed concrete railroad ties are manufactured by the slip form process in the absence of mold members, other than the slip form itself. Tie casting occurs on portable casting soffits between portable soffit anchored deadmen supporting the pre-stressed tie tensile members immediately overlying the casting soffit. Tie formation occurs with the slip form passing around and over the pre-stressed tension members. Track fastening hardware is vibrationally inserted through windows of the slip form to place the track fastening hardware to precise measured dimension along the route of slip form movement and to configure that portion of the tie adjacent the track fastening hardware. End of tie locations as well as tie batch identification are likewise marked during the slip form process. Upon cure, the ties are cut at their marked end location.

Abstract: A process for encasing articles, particularly encasing cable splices, cable termination, a radially expanded tube made of a rubbery elastic material is positioned on the article. The tube is maintained in the expanded condition by a tension medium in the form of a plastic tube attached to the outer surface of the tube. The attachment between the surface of the tube and the tension medium is removed for the purpose of resetting the tube. The resetting is accomplished by cooling the plastic tube to a sub-ambient temperature thereby destroying the plastic tube.

Abstract: In a method and apparatus for manufacturing a slide fastener chain having rows of coupling elements and members of a separable bottom end stop assembly, two positioning holes are formed at predetermined positions on reinforcing films attached to a pair of fastener tapes. The positioning holes are used to position the fastener tapes relative to a molding unit with respect to each individual slide fastener length. Thus, even when a positioning error is produced due to a change in tension on the fastener tapes being processed, such error is limited to a small extent which is created only in the individual slide fastener length. Thus, the coupling elements and the first pin member and the second pin member can be molded precisely.

Abstract: A synthetic reinforcement having a plurality of recesses on a surface to facilitate adhesion to wood structural members and a process for making the same is disclosed. The synthetic reinforcement is comprised of a plurality of continuous fibers that are maintained in position by a resin encasement. The surface of the synthetic reinforcement is characterized by recesses that are located in a generally random pattern, which increases the surface area of the resin encasement. The synthetic reinforcement is connectable to wood laminae or itself with commercial grade adhesives such as the resorcinol resins, which are suitable for adhering the wood laminae together.

Abstract: A method for the manufacture of pretensioned prestressed concrete sleepers wherein, the tensioning wires are taken directly from one or more rolls of wire and are introduced in a longitudinal feed into a tensioning frame, and the tensioning wires (5) are initially anchored at the end thereof located at the front in feed direction. The wires are tensioned by a tensioning device arranged outside of the tensioning frame and resting against the opposite end thereof, and the wires (5) are anchored at the tensioning device; only then are the wires severed by means of a severing device. In this manner, it is possible to combine in a single station the operating stages of cutting to length, introducing and tensioning the wires, which stages in the past were distributed over several manufacturing stations, so that the labor intensive and time consuming manipulation of wires which have been previously cut to length is eliminated.

Abstract: A method of constructing a double-walled tank includes forming the two containers, and removing the top of the containment shell and filling it with hot water so that the containment shell expands temporarily increasing the diameter of the side wall of the containment shell. The primary container is positioned in alignment over the containment shell and is lowered into contact with the hot water, and is filled with cold water of a temperature at least about 70.degree. F. less than the temperature of the hot water so that the primary container contracts temporarily decreasing the diameter of the side wall of the primary container, and allowing the primary container to sink into the containment shell while displacing the hot water from the containment shell until the primary container is resting on the bottom of the containment shell.

Abstract: A method of making a plurality of toothed belt constructions and a set of such belt constructions are provided, the method including the steps of disposing tubular sleeves of stretchable fabric material respectively onto a plurality of toothed mold members having different diameters, forcing mold material against the outside surfaces of the sleeves to tend to stretch the fabric material into the grooves of the toothed mold members as the mold material enters the grooves of the mold members so that the resulting toothed belt constructions will have the fabric material thereof carried in certain positions relative to the respective teeth thereof, and forming the sleeves from the same fabric material and with the same diameters in the nonstretched condition thereof.

Abstract: In a glass lid (1) for a vehicle roof opening, the glass pane (2) is provided in its edge zone all around with a cast-on or foamed-on plastics border (3). At least at the longer sides of the glass pane (2), curved correspondingly to the roof curvature, stiffening profiles (4, 5) of steel, supporting the glass pane from below, are embedded into the border (3). The stiffening profiles (4, 5) have, before embedding, a curvature different from that of the glass pane and, in the completed lid (1), are elastically bent corresponding to the curvature of the glass pane so that they are embedded with prestress in the border (3), in order to counteract uplift forces acting upon the lid (1) while the vehicle is travelling, in the sense of maintaining the shape of the lid (1).

Abstract: A shirred fibrous casing article containing about 20% to about 30% moisture by total casing weight and composed of shirred portions spliced together and retained in an overwrap wherein a flag which identifies the splice location between the shirred portions is extended radially through the overwrap.

Abstract: A stopper for a rope which is injection molded on the rope. The stopper has a sleeve-like shape and surrounds the rope without play and prevents an axial slippage of the stopper from the rope. A strut is formed as one piece with the stopper and extends radially through the inner diameter of the rope. Also a method of forming a stopper on a rope is included.

Abstract: A reinforcing panel and process for making the same for use in reinforcing wood structural members including laminated beams, wood I-beams, and trusses. The reinforcing panel is comprised of a plurality of synthetic fibers that are arranged parallel to one another and aligned with the longitudinal direction of the panel, and accordingly the wood structure. The panel has substantially no transverse fibers. The fibers are maintained in position by a resin encasement that completely encloses the fibers with the exception of some fibers that are closest to the surface. The surface of the reinforcing panel is treated so that those fibers closest to the surface of the panel are caused to "hair up" so that the reinforcing panel may be used with non-epoxy adhesives which are commonly used in the laminated beam industry, such as resorcinol.

Abstract: A method for introducing a prestress into a concrete member includes the steps of passing a steel rod (2) through a hollow steel rod (1), applying a tensile force to the hollow steel rod (1), while using the steel rod (2) as a reaction support member, placing concrete (4) around the hollow prestressed steel rod (1), and hardening the concrete (4). The apparatus includes a flat bearing support plate that abuts the concrete to be prestressed, a jack and ram, a rigid support member for interconnecting the jack and ram to the bearing support plate, and a holding cylinder positioned between the bearing support plate and the jack and ram. The bearing support plate and a leading end of the holding cylinder are apertured and screw threadedly receive the threaded trailing end of a hollow steel rod. The trailing end of the steel rod is screw threadedly received by the trailing end of the holding cylinder.

Abstract: A method and apparatus are shown for lining a tubular member with an elastomeric liner having an outside diameter which is initially greater than the inside diameter of the tubular member. A series of downsizing rollers reduce the outside diameter of the liner a preselected amount. A series of shaping rollers form the downsized liner into an ellipse, thereby allowing the downsized liner to be guided around bends and turns into the interior of the tubular member. After insertion, the liner is allowed to expand to substantially its original outside diameter to secure the liner within the tubular member.

Abstract: A method and apparatus are shown for lining a host pipe with an elastomeric liner having an outside diameter which is initially greater than the inside diameter of the host pipe. A length of the liner is reduced to a downsized outside diameter and the downsized liner is cryogenically cooled to a supercooled state to maintain the downsized dimensions of the liner while increasing the tensile strength to facilitate insertion of the liner into the host pipe.

Abstract: A tendon for prestressed concrete structure comprises a core member such as a steel wire for prestressed concrete structures, a steel strand for prestressed concrete structures or a steel bar for prestressed concrete structures, and an unset bonding material coating the core structure in a predetermined thickness, having a specific setting time determined by selectively determining the respective contents of the ingredient of the bonding material and capable of setting at an ordinary temperature. The tendon is arranged in a desired arrangement for forming a prestressed concrete structure, concrete is placed so as to bury the tendons therein, and then the tendons are tensioned and fixed after the strength of the deposited concrete has increased to a degree to permit tensioning the tendons and before the unset bonding material sets. Thus, the unset bonding material sets after the tendons have been tensioned and fixed to bond the tendons firmly to the prestressed concrete structure.

Abstract: A stripping station which is used for stripping a mold from a cast concrete lamp pole has a mold that has an axial compressive load placed thereon by a tension force applied to tension members running through the mold. The tension members are secured to anchors located at one end of the mold. A stripping fixture attached to the anchors exerts a tension force sufficient to relieve the axial compressive load on the mold and transfers the axial load to the frame of the stripping machine. This allows the mold to be removed. The axial compression load is transferred to the pole after the mold is stripped.

Abstract: The invention provides an apparatus and method by which an opening into a lateral pipe connection for a pipeline into which a liner is being installed may be sealed and protectively lined. The invention features a bushing which is emplaced in the lateral connection by use of an expandable mandrel and a control means. The bushing includes an integral heating element for softening the thermoplastic material from which the bushing is formed. O-rings are positioned between the bushing and the lateral pipe to form a seal.

Abstract: A method and an apparatus for making an endless, flat, flexible belt of pourable plastics include a core, especially a multiple core, as tension bearer, for example in a conveyor belt of polyurethane. Spaced apart support filaments extending transversely of the longitudinal direction of the belt are tightened in a mold approximately in the center plane of the belt to be cast so that the tension bearer will be placed as accurately as possible in the middle, based on the thickness of the belt to be produced. Subsequently the tension bearer is wound in longitudinal direction of the belt on the winding support formed by the support filaments. Thereupon liquid plastic material is poured into the mold and following that the support filaments protruding from the side surfaces of the belt are cut off upon termination of the curing.

Abstract: Disclosed are a motor casing made of a resin and a method of manufacturing such a motor casing. A bearing for rotatably supporting a core shaft of a rotor core is inserted into a bearing seat portion of the motor casing when the temperature of the resin material which forms the bearing seat portion is substantially at the glass transition temperature thereof or above, the resin material being cooled to a room temperature.

Abstract: A prestressed concrete beam is made by first fitting the opposite ends of a group of reinforcing rods through respective holes in a pair of longitudinally spaced end plates having longitudinally confronting inner faces and opposite outer faces, then providing on each of the rods a head bearing longitudinally inward on the respective outer face, and then applying opposite outward traction to the end plates to tension the rods and filling around the rods and between the inner faces of the plates with a mass of concrete. The concrete mass is then cured and the traction on the end plates is released. Subsequently the heads of the rods are released from the plates and the plates are removed from the ends of the mass of cured concrete. The heads can be machined or burnt off, or the plate can be constructed to release them.

Abstract: An annular, elastomer bulkhead gasket for sealing pipe fittings at concreate structures. A tubular body portion includes an annular casting flange having a three-quarter radiused peripheral edge which radially projects from an outer surface. A half radiused annular bead projects from an inner surface to seal around a fitted pipe. The gasket is securable to an annular flange of a conically tapered mandrel which is securable to a casting form wall. The mandrel retains and supports the gasket in compresed relation between the casting form walls during the pouring of the bulkhead.

Abstract: Assembly of the ski is effected in one preliminary step in which a mechanical resistance sub-assembly is produced, followed by a single molding step. During the preliminary step, at least one lower reinforcement piece (1), a core (2), and an upper reinforcement piece (3) are stacked together, said stacked assembly is inserted in a heat retractable casing (4), and the casing is heated to shrink it retracted. During the single molding step, the lower elements of the ski structure (11, 12, 13) are placed in the mold, the mechanical resistance sub-assembly is placed on the lower elements of the ski structure, the mold is closed, and a thermohardenable polymer is injected so as to form the protective covering (15) of the ski.

Abstract: A steel reinforced cement product having substantially increased strength made by: positioning prestressed reinforcing steel in a mold cavity; providing a cementitious mixture in the mold cavity about the reinforcing steel in an amount sufficient to fill the mold cavity to a predetermined extent; curing the reinforced cementitious-steel composite article in the mold; drying the article; applying a glaze to the surface of the dried article; burning the glaze; cooling the burned, glazed article, whereby reducing the strength of the composite article; hydrating the reduced strength composite article; and then recurring the thus produced article.

Abstract: A thin-walled ferrocement product is formed from mortar supplied in a liquid or semi-liquid state, and a thin foraminous layer of reinforcement positioned centrally between the opposite wall surfaces of the product. The liquid or semi-liquid mortar is deposited in a uniform layer on a conveyor and the reinforcing material is positioned parallel to the lower surface of the conveyor. In a preferred embodiment, the material is maintained under tension at the desired position above the conveyor surface as the mortar is deposited onto the conveyor and flows through the foraminous reinforcing layer. The mortar is developed to a coherent plastic state before removal from the conveyor, preferably with the application of heat. The developed plastic material may be formed into various configurations, or may be maintained flat, while subjected to curing to a solid state. The developed plastic ferrocement material may be separated into convenient lengths for handling.

Abstract: A method of forming an integral intermediate layer in a flexible single injection molded component is disclosed. According to the method a strip comprising the sandwiched layer is securely positioned within a molding cavity. During injection of the mold material a tensile force is applied throughout the strip in a plane orthogonal to a critical component direction. The method is particularly suited for the fabrication of wrist mounted electronic devices having an electrical connection to a conductive member integrally housed within a molded wristband.

Abstract: A tubular plastic liner having a coefficient of thermal expansion greater than the coefficient of thermal expansion of a pipeline is cooled to reduce its outside diameter below the inside diameter of the pipeline, which is also cooled, and is then pulled into the pipeline. After the pulling operation is completed the liner and pipeline are allowed to return to normal temperature, whereupon the liner expands to conform to the inside diameter of the pipeline.

Abstract: A method and apparatus for constructing an above ground concrete encased storage tank. The apparatus has a support assembly that extends from the baseplate of a concrete form, that supports, elevates, and secures an inner storage tank from the form baseplate, so that the tank may be completely surrounded by concrete. The form has removable walls that may be pivotally attached to the baseplate and initially in a horizontal position. The support assembly has anchor bolts that extend through holes in the baseplate. The anchor bolts are screwed into anchor nuts that are attached to a pair of brackets. The anchor nuts and brackets are spaced from the baseplate by sleeves that fit over the threaded portions of the anchor bolts. The brackets are constructed to support the storage tank, which is placed in the form on top of the support assembly. The tank is then fastened to the support assembly.

Abstract: In casings for switch cross ties, the bottom plate 3 serves at the same time as a pattern for the position of the construction components. As a rule, a new casing is prepared for each series of cross-ties type. In small series with various positions of the construction components it is economical to use the bottom plate repeatedly. This is done by providing the bottom plate, prior to its insertion in the casing, with holes (A,B,C) for several types of finished parts, by provisionally closing the unnecessary holes by suitable means and by finding the combination of holes required for the production of a certain type of finished part through a certain searching procedure and freeing them of their provisional closing means.

Abstract: Extruded thermoplastic members, particularly structural members, are reinforced by longitudinally extending pre-stressed elements, such as filaments or matting. The elements, while under tension, are drawn into an extrusion crosshead die forming the thermoplasatic member. The elements are fully imbedded within the thermoplastic material while under tension and curing of the thermoplastic material, and final curing of the tensioned reinforcing elements, if a thermosetting resin impregnated element is used, occurs while the elements are under tension, the material of the member and the elements intimately bond and the tension forces within the elements reinforce the member at the desired locations. The forming of the reinforced member is a continuous operation.

Abstract: A prestressing arrangement and technique for the manufacture of prestressed bodies or structures includes shape memory material members. According to one aspect of the invention, the prestressing arrangement includes a tensile member in series with a shape memory material member. The formable material is shaped around the members and fixed in form. The shape memory material is then shrunk by heating it above its characteristic threshold temperature, placing the members in tension and the fixed material in compression. According to another aspect, the shape memory material member is secured in a tube. Prestressing is achieved in the tubular prestressing arrangement by lengthwise expansion of the shape memory material member prior to fixing the material of the body being formed, and then after fixation, releasing the stress on the shape memory material member, leaving the tube in tension to exert compressive forces on the fixed material.

Abstract: In a concrete column supporting an overhead load and having a base end resting on a surface, a process of strengthening the column to increase its ability to withstand atypical physical loading accompanying an earthquake, involving the steps of defining a work area about the surface of the column to which the strengthening is to be applied, the work area defined by circumferential marginal edges arranged in spaced-apart relation; overwrapping the work area with at least one layer of high-strength, stretchable fibers wherein the fibers are oriented at an angle to the vertical axis of the column; applying a coat of hardenable material, having a modulus at least as great as that of the fibers, over the layer of fibers to form a hard outer shell thereover; and, injecting a quantity of a hardenable, low-shrink liquid under the layer of fibers and over the surface of the work area in an amount sufficient to cause the fibers to undergo stretching from about 1/2% to about 4% of their elongation.

Abstract: A method for preparing cross-sections of yarn samples along the plane perpendicular to the yarn's longitudinal axis is disclosed. This method involves the steps of passing the yarn through a hollow capsule so that the axes of the yarn and the capsule are aligned in parallel, tensioning the yarn to remove any crimp, forming a solid stub inside the capsule to fix the position of the tensioned yarn, and then cross-sectioning the stub perpendicular to its longitudinal axis.

Abstract: A tire clad concrete log and method and apparatus for forming a tire clad concrete log. The method includes the steps of providing a plurality of used tires which are made into a form by placing them in sidewall-to-sidewall contact, providing a quantity of a waste ash which is mixed as a binder in a manner making a concrete material, and filling the form with the concrete material while also maintaining the used tires in sidewall-to-sidewall contact. The tire clad concrete log thus comprises a plurality of used tires disposed in sidewall-to-sidewall contact wherein a concrete material formed at least in part by waste ash is interlockingly disposed within the used tires.

Abstract: The invention concerns a prestressed construction element of composite structure comprising a bar- or tendon-like inner part (1) of high tensile strength, a sheat part (2) of, e.g., high-strength concrete or ceramic material, adapted about and precompressed by the inner part (1), and a shape-forming structure (4) adapted about the sheath part (2) with dimensions corresponding to the desired dimensions of the construction element. According to the invention, the structure (4) is such an elastic material as is capable of taking both compression and tensile stresses without cracking. The construction in accordance with the invention achieves a strong and easily workable construction element.

Abstract: Extrusion die assembly and method of insulating conductor in which tensile reinforcing elements are introduced into the conductor insulation as it is being extruded. During extrusion, the reinforcing element engage outwardly against a position control member to limit their outward movement. The extrudate flows to either side of the position control member and recombines into a single unitary mass downstream of the control member.

Abstract: A method and apparatus are shown for lining a tubular member with an elastomeric liner having an outside diameter which is initially greater than the inside diameter of the tubular member and a length which is greater than the length of the tubular member. A length of the liner is reduced to a downsized outside diameter and inserted into the tubular member to be lined. The liner is allowed to expand to substantially its original outside diameter to thereby bond the liner within the tubular member, the liner opposite ends still extending outwardly from the opposing ends of the tubular member. The outside diameter of the liner opposite ends is then increased to approximately the outside diameter of the tubular member by heating and reforming that portion of the liner opposite ends which extends outwardly from the opposing ends of the tubular member.

Abstract: The maximum safe operating speed of flywheels and shafts made of low tensile strength material is often determined by the speed at which radial tensile stress exceeds a radial tensile stress limit for the material. Circumferentially wound fiber composite material, for example, has a relatively low tensile strength along the radial direction perpendicular to the fibers. To increase the maximum safe operating speed, it is therefore desirable to form a fiber composite flywheel or shaft with radial compressive prestress. Such a prestressed flywheel or shaft is made by placing a cylinder within a fiber composite annulus, injecting a bonding agent under pressure into the interface between the annulus and the cylinder, and maintaining the bonding agent under pressure while the bonding agent solidifies. Preferably, the cylinder and annulus are aligned in a concentric relationship during solidification by a chamber into which the cylinder and annulus are placed.

Abstract: A method is disclosed for the manufacture of an electrofusion coupler, for connecting adjoining lengths of thermoplastics pipes, and which coupler takes the form of a sleeve of thermoplastics material, to receive adjoining ends of adjoining pipes, the sleeve having an electrical resistance heater embedded therein and extended around the sleeve. In the method, a plastics preform is wound with a resistance heating wire, while heating the wire, to melt the surface of the preform, or applying molten plastics to the preform in the vicinity where the wire runs onto the preform, in order to ensure that the heating wire is fully embedded in the preform. A pressing roller may be run over the preform surface before the molten plastics has solidified, in order to smooth over the molten plastics. The preform 10 is subsequently placed in an injection mould and an outer encapsulating jacket is injection moulded around the preform.

Abstract: A method of manufacturing a three-sided culvert includes prestressing tendons in the culvert form. A series of prestressing tendons are secured within a form adapted for casting a concrete culvert having three orthogonal sides. The prestressing tendons are utilized in the top slab of the three-sided culvert and are positioned within the form prior to the pouring of concrete therein. Reinforcing steel can be eliminated along with the costs associated therewith and a culvert configuration can be provided with enhanced strength and improved material properties. Such culverts may thus be provided in modular form for placement upon foundations at remote locations for the creation of bridges, drainage areas and the like.