Abstract: The invention relates to a plug connection between two tubular workpieces (1, 2) which are made of concrete and each of which has an inner liner (5) made of plastic, one of which forms a tip end (3) and the other a socket end (4) receiving the tip end (3), wherein the inner liners (5) have circumferential sealing flanges (12) which cover the end face (13) of the tip end (3) or the socket face (14) and wherein a joint seal (16) is provided between the sealing flanges (12). In order to provide advantageous structural conditions, it is proposed that the inner liners (5) are provided with a circumferential elastomer angled profiled section (8, 9) at the end face, which receives the circumferential edge of the inner liner (5) in an end-face profiled groove (11) of its axially parallel limb (10) and whose limb at a right angle to the axis forms the sealing flange (12).

Abstract: A prefabricated part comprises a concrete body that has the form of a pipe section with two pipe ends and a pipe inner side. The pipe inner side is lined at least in some areas by a lining made of plastic material connected to the concrete body, and at least one of the pipe ends is covered at least in some areas by a molded part made of plastic material connected to the concrete body. At least the pipe end, which is covered at least in some areas, has a connecting joint in order to connect the pipe end to a pipe end of a further prefabricated part. The lining consists of a thermoplastic material and the molded part consists of a thermosetting plastic. The lining and the molded part are connected to each other in a sealed manner.

Abstract: Structural body comprises a concrete core and a cap around the opening. A first wrap is wrapped under tension around the concrete core and a portion of the cap to form a continuous water resistant barrier around the outer surface of the concrete core. A second wrap can be wrapped under tension around the inner surface of concrete core to form a continuous water resistant barrier around the inner surface of the concrete core. Structural body can be formed as a pipe with a male and female ends to interconnect multiple pipes. The joint formed between two structural bodies has a continuous water resistant barrier that prevents the environment from contacting the concrete core.

Abstract: A medical tube which is relatively thin in thickness over its entirety while an outer layer and an inner layer are preferably prevented from being separated from each other. A medical tube includes a first layer and a second layer that is provided adjacent to an inner circumferential surface of the first layer. The medical tube also includes a wedge-shaped convex portion that is provided on an outer circumferential surface of the second layer so as to be widened in width radially outward, and a concave portion that is provided on an inner circumferential surface of the first layer, with the convex portion and the concave portion engaging each other.

Abstract: A method of lining an interior of a pipe in need of repair comprises providing a carrier tube having one or more expandable materials, coating the carrier tube with a binder, securing one or more layers of a fiber-laden material along an exterior surface of the carrier tube with the assistance of the binder. The carrier tube is delivered, together with the at least one layer of the fiber-laden material and the binder, to a targeted location inside a pipe in need of repair. The carrier tube comprises a first diameter while the carrier tube is being delivered to the targeted located inside the pipe in need of repair. The method additionally comprises radially expanding the carrier tube from the first diameter to a second diameter, such that the one or more layers of the fiber-laden material and the binder at least partially contact and/or adhere to an interior wall of the pipe.

Abstract: A load-bearing structure and a method of producing a load-bearing structure, in particular a tower of a wind energy plant, provides a hollow concrete part with an outer wall which is manufactured by several layers produced in wet-on-wet technology. The outer layer is a fine-grain concrete layer provided with a textile reinforcement, and the inner layer is made of bulk concrete.

Abstract: A fuel head assembly (120) for a pulverized coal nozzle includes removeable back cover (123) that may be removed substantially horizontally to allow access to liners (141,143,145) inside of the fuel head assembly (120) for servicing. This may be used in places where there access from above the fuel head assembly (120) is restricted. The liners (141,143,145) are constructed of a wear-resistant material and include curved vanes (131,133) for more evenly distributing pulverized solid fuel particles, and for reducing erosion of the fuel head assembly (120).

Abstract: A polyaxial bone anchoring device includes a bone anchoring element having a shank and a head, a receiving part including a rod receiving portion, and a head receiving portion having a first end and an open second end with a bounding edge, wherein the head receiving portion is configured to be rotatably connected to the rod receiving portion and is flexible for introduction and clamping of the head, and a locking ring configured to be mounted around the head receiving portion, wherein the head is insertable into the head receiving portion from the second end, is pivotable in the head receiving portion at a larger maximum pivot angle relative to the receiving part at a first location of the bounding edge, and can be locked at an angle relative to the receiving part by compressing the head receiving portion with the locking ring.

Abstract: The present invention provides for a manufacturing apparatus for forming a ceramic preform from an extrudate having a first end and a second end. A cutter forms the first and second ends of the extrudate complementary to each other such that the first and second ends of the extrudate align with each other in a spaced relationship to define a preform having a substantially uniform exterior surface and a substantially uniform thickness. The present invention provides for a method of forming the preform from the extrudate having the first and second ends utilizing a mandrel. The method includes the step of aligning the second end complementary to the first end of the first layer in a spaced relationship to define the preform having the substantially uniform exterior surface and the substantially uniform thickness.

Abstract: Pressure cast lined steel pipes comprise an annular concrete or mortar liner along an inside diameter, and a metal shell surrounding the liner, wherein the liner is in direct contact with the metal shell. The wall thickness of the liner can be from 10 to 50 times the thickness of the metal shell. The pipe may be coated with a dielectric material. A mold assembly used to form the pipe includes an annular concrete or mortar composition chamber formed between the metal shell and an inner mold member. Pressurized water is used in the mold assembly to pressurize the concrete or mortar composition and exert a desired pressure force onto the metal shell while the composition cures in the mold. Once a desired degree of cure is achieved, the pressure is removed causing the metal shell to exert a desired compression force onto the cured liner.

Abstract: A vibration-resistant reinforced concrete watertight pipe, at opposite ends of which coupling units formed of a separate material are formed, and a method of manufacturing the same are provided. The vibration-resistant reinforced concrete watertight pipe includes a reinforced concrete pipe having a reinforcement mat, which is assembled with longitudinal reinforcements and transverse reinforcements, disposed in a concrete layer, and a convexity coupling part and a concavity coupling part that are coupled to opposite ends of the reinforced concrete pipe and have coupling ridges and coupling furrows respectively. Here, the coupling part and the concavity coupling part are formed of a synthetic resin, which is different in physical properties from the reinforced concrete pipe, and have the same shape and thickness as the reinforced concrete pipe. Each of the convexity coupling part and the concavity coupling part has a metal core installed therein to increase a coupling strength.

Abstract: A pre-stressed concrete pipe is taught that incorporates a cylinder (20), an annular ring (34) and an annular offset member (40) welded together. A seal band (44) stretches over the annular offset member and the assembled annular ring is welded within a first end (22) of the metallic cylinder. A strip of pressure sensitive tape (54) seals the internal interface. An O-ring (52) is positioned around the annular ring during joint attachment of a pipeline. The cylinder second end (24) utilizes a hat member (56) and a resilient seal band (44a) stretched over the hat member with the assembled hat member welded within the second end of the cylinder. A strip of pressure sensitive tape (54) seals this interface. A film layer of release agent (64) is adhered to the inside of the metallic cylinder where a concrete tube (68) is cast within the cylinder.

Abstract: Pressure cast lined steel pipes comprise an annular concrete or mortar liner along an inside diameter, and a metal shell surrounding the liner, wherein the liner is in direct contact with the metal shell. The wall thickness of the liner can be from 10 to 50 times the thickness of the metal shell. The pipe may be coated with a dielectric material. A mold assembly used to form the pipe includes an annular concrete or mortar composition chamber formed between the metal shell and an inner mold member. Pressurized water is used in the mold assembly to pressurize the concrete or mortar composition and exert a desired pressure force onto the metal shell while the composition cures in the mold. Once a desired degree of cure is achieved, the pressure is removed causing the metal shell to exert a desired compression force onto the cured liner.

Abstract: A vibration-resistant reinforced concrete watertight pipe, at opposite ends of which coupling units formed of a separate material are formed, and a method of manufacturing the same are provided. The vibration-resistant reinforced concrete watertight pipe includes a reinforced concrete pipe having a reinforcement mat, which is assembled with longitudinal reinforcements and transverse reinforcements, disposed in a concrete layer, and a convexity coupling part and a concavity coupling part that are coupled to opposite ends of the reinforced concrete pipe and have coupling ridges and coupling furrows respectively. Here, the coupling part and the concavity coupling part are formed of a synthetic resin, which is different in physical properties from the reinforced concrete pipe, and have the same shape and thickness as the reinforced concrete pipe. Each of the convexity coupling part and the concavity coupling part has a metal core installed therein to increase a coupling strength.

Abstract: An electrical conduit encasement including a top section and bottom section secured together by mortar and adjacent encasements by mortar. A pair of vertically extending threaded rods suspend the concrete encasements with the rods extending through members attached to plates embededly attached to the encasements.

Abstract: A pressure pipe for transporting corrosive material, such as ozonated water, is formed with a pipe joint that is resistant to ozone. An intermediate portion of the pressure pipe is formed from a low-carbon steel cylinder with inner and outer concrete layers and prestressing wire. A stainless steel slip joint member is attached to an end of the low-carbon steel cylinder to facilitate joining adjacent pipe sections. The stainless steel slip joint members resist the corrosive effects of ozone, while the inner concrete layer protects the low-carbon steel cylinders of the intermediate portion. In one aspect of the invention, a water treatment system constructed from pressure pipe as described above is connected as a bypass loop to a primary pipe run from a water source to a treatment plant. Ozone is introduced to water diverted through the bypass loop. The water decomposes prior to being reintroduced back into the primary pipe run.

Abstract: In order to reinforce a cylindrical pipeline, in particular an underground water supply pipeline, prestressing reinforcements are placed and tensioned around it. In a zone where the pipeline has a radial projection, for example providing a manhole for access to the inside of the pipeline, the prestressing reinforcements are deflected to bypass the radial projection so that the reinforcements, located in the same layer on a side of the pipeline opposite the side having the projection, are distributed in a plurality of layers on this side having the protuberance.

Abstract: A structural reinforcing layer made from wire, a structural reinforcing composite layer made from wire, and the resulting load bearing structures made from or retrofitted with wire reinforced plastics and cements. Said layers and structures made from monofilament metallic or pre-cured composite materials twisted into multi-strand wire geometry optimized to mechanically shear load into rigid thermoplastic, thermoset, metallic or cementious resin systems. Wire geometry, count, size and strength/stiffness can be varied in combination with resin type, sheet structure, permeability and orientation to create layers intended for use in composite and cement based structures as originally molded reinforcement or retrofitted structural upgrades.

Abstract: The present invention relates to a conduit repairing material, repairing structure, and repairing method thereof, and particularly provides a repairing method for an existing conduit characterized by comprising using a plurality of reinforcing members capable of being carried in the existing conduit, assembling said reinforcing members into a hollow skeleton-like reinforcing body extending substantially along the inner surface of the existing conduit, attaching a plurality of inner face bars to the inside of the reinforcing body to assemble them into a tubular form along the lengthwise direction of the conduit, and injecting a curable infilling into the gap between the inner face bars and the inner surface of the existing conduit.

Abstract: The present invention relates to a conduit repairing material, repairing structure, and repairing method thereof, and particularly provides a repairing method for an existing conduit characterized by comprising using a plurality of reinforcing members capable of being carried in the existing conduit, assembling said reinforcing members into a hollow skeleton-like reinforcing body extending substantially along the inner surface of the existing conduit, attaching a plurality of inner face bars to the inside of the reinforcing body to assemble them into a tubular form along the lengthwise direction of the conduit, and injecting a curable infilling into the gap between the inner face bars and the inner surface of the existing conduit.

Abstract: An insulating system for pipes is provided which includes at least two different types of pipe insulation, wherein each pipe insulation is a pipe jacket formed by two mating sections, a first section and a second section with each section having a mating surface, wherein further when the two mating sections are put together with the mating surface of the first section exactly abutting the mating surface of the second section, they form a tubular structure having a bore which is a suitable size to receive a pipe. Of the three possible types of pipe insulation available, insulation A, insulation B, and insulation C, each pipe insulation type is formulated to insulate pipes having a different surface temperature, and yet pipe insulations A, B, and C each have identical outer diameters.

Abstract: The invention relates to a device reinforcing circumferential welds 8 which join two contiguous pipes 6 and 7 in order to increase the fatigue life of said welds by reducing mechanical stresses in them when being subjected to periodic bending.

Abstract: A clip-on stirrup mat for a concrete reinforcement cage comprises at least one and preferably a plurality of resilient clips attached to the stirrup mat and extending outwardly therefrom in the direction of application of a mat to a cage. The clip has a relatively narrow outer end that fits between adjacent wires in the cage and has inwardly extending, diverging first and second legs that lead to more widely spaced distal ends that form an inner end of the clip. The first leg is attached to the mat adjacent a distal end of the leg, and the second leg is resiliently deflectable toward the first leg. The clip and legs are shaped and positioned on the mat such that, as the mat is attached to the cage, the outer end of the clip fits through adjacent wires in the cage and the second leg engages and is deflected toward the first leg by one of the adjacent cage wires. The second leg includes a gripping surface thereon, which may be convolutions, that engages a wire on the cage as the mat is installed on the cage.

Abstract: There is disclosed a hollow reinforcing element for casting into composites, which in use defines passageways that may communicate to the exterior of the composite and that can serve as conduit arrays in structures formed from the composite. Benefits include superior strength to weight ratios, reduced thermal stresses, suppression of crack propagation, and improved corrosion protection. The hollow reinforcing elements may also be used to provide antennae, drain systems, leveling devices, containment structures and pneumatic levitation of vehicles.

Abstract: An outer pipe casing (20) and a concrete tube (26) cast inside, form a pre-stressed concrete pipe in its elementary form. Prior to casting, a layer of non-cohesive material (28) is sprayed on the inside of the pipe casing and an annular ring (32) is welded inside adjacent to each end. A resilient seal ring (46) is captivated into the inwardly facing legs (38) of the second channel (36) of each annular ring and a temporary seal (52) separates each annular ring from the material (28). After the concrete of the tube cures, a pressurized solidifying compound (54) is inserted under pressure to a pathway (42) formed into each annular ring and it is also extruded into a region (30) coated by the non-cohesive material. Pressurization of the compound is sufficient to cause the pipe casing to bulge outwardly and compression of the concrete in the tube is achieved. When the compound hardens, the compressive force remains and pre-loads the pipe.

Abstract: An insulation blanket for a pipeline, comprising at least one insulating cell, wherein the or each insulating cell comprises a protective layer and an insulating layer.

Abstract: Cast iron pipe and other elongated hollow articles are lined with a cementitious mortar for certain applications, such as the transmission of potable water or sewage. To improve the resistance to attack from acids and to provide a crack and holiday free cement lining, a calcium alumina cement is used to line the article. A plasticizer such as fireclay is added to the calcium alumina cement prior to its application. The cement lined article is then coated with an asphaltic based coating and then cured in a high humidity environment.

Abstract: A concrete pipe and methods for forming the same are presented by this invention. The pipe includes an inner and outer sleeve separated by a spacer ring which creates a void therebetween. Concrete is poured within this void to solidify the pipe structure. The spacer ring is formed by a plurality of interlocking ring forms which have nesting members to allow for the interconnection thereof. In an alternative embodiment, interlocking forms are employed to form both the inner and outer surface of the pipe. These alternative forms provide convex nesting numbers which form internal conduits between the inner and outer surfaces that accept reinforcing members or connection members to interlock the forms to one another. Concrete is then filled in these conduits and between the void of the inner and outer surfaces to solidify the pipe construction. Both embodiments may employ a plurality of elbow forms to form a bell-mouth which connects with the end of an adjacent pipe.

Abstract: A self locking stirrup mat for providing supplemental support for wire cage concrete reinforcement comprises a stirrup mat formed of a grid of interconnected wires preferably with manually formable tie wires, stirrup elements projecting from the grid, and a self-locking attachment mechanism for attaching the stirrup mat to a wire cage. The self-locking attachment mechanism comprises a plurality of clips fixed at spaced locations on the grid. The clips are shaped and positioned to receive cage wires therein through inlets that are engaged by moving the stirrup mat on the surface of the cage. The clips have one-way inlets that resist removal of the cage wires from the inlets with considerably more force than needed to insert the cage wire into the inlets. In one aspect of the invention, the clips are formed of flat elongated resilient steel loops welded to the tie wires at inclined angles.

Abstract: A conduit for the circulation of fluid under pressure comprising a tubular enclosure delimited by a thin wall and fixed on a rigid base slab of molded material. The upper part of the enclosure comprises, in cross-section, at least three thin wall segments, including two lateral segments each extending from a lower side to an upper side, and at least one upper segment closing the enclosure by connecting the upper sides of the lateral segments. Each lateral thin wall segment is joined to a rigid support element of molded material fixed at its base to the corresponding side of the slab and comprising an inner surface conjugate with that of the lateral segment onto which the latter is applied. The inner surface extends from the level of the upper surface of the slab as to a level sufficient to maintain the rigidity of the lateral segment over its entire height.

Abstract: Methods and apparatus for continuously extruding a hydraulically settable mixture and simultaneously placing continuous filaments within the extruding mixture to yield articles having a filament-reinforced, hydraulically settable matrix. The filaments can be placed within the mixtures in a parallel configuration, a helical configuration, or combinations thereof, in order to yield an article having the desired properties of, e.g., tensile strength, flexural strength, hoop strength, burst strength, toughness, and elongation ability. The desired properties of the hydraulically settable mixture, as well as of the cured hydraulically settable matrix of the hardened article, may also be adjusted by including varying amounts and types of aggregates, discontinuous fibers, binders, rheology-modifying agents, dispersants, or other admixtures within the hydraulically settable mixture.

Abstract: Unreinforced or reinforced concrete moldings, for example concrete pipes, with improved corrosion resistance to acids and acidic sewage, improved permeation resistance to inorganic and organic liquids and gases and improved mechanical stability, produced by molding with machines, for example in press molding machines or extrusion machines or concrete pipe pressing machines, and allowing to harden plastic-viscous concrete mixtures of hydraulic inorganic binders, preferably cement, aggregates and water, where, in the preparation of the plastic-viscous concrete mixtures, to the latter has been added in a positive mixer an effective amount of an aqueous plastics dispersion based on anionic and hydrolysis-resistant copolymers of ethylenically unsaturated monomers, the minimum film forming temperature (MFT) of which is above the setting temperature of the concrete mixture, preferably above 23.degree. C.

Abstract: Conduits having cement-containing liners for the inner and outer surfaces of metal pipes include a fibrous material, such as glass fibers, to prevent cracking and/or inhibit crack propagation.

Abstract: Unreinforced or reinforced concrete moldings, for example concrete pipes, with improved corrosion resistance to acids and acidic sewage, improved permeation resistance to inorganic and organic liquids and gases and improved mechanical stability, produced by molding with machines, for example in press molding machines or extrusion machines or concrete pipe pressing machines, and allowing to harden plastic-viscous concrete mixtures of hydraulic inorganic binders, preferably cement, aggregates and water, where, in the preparation of the plastic-viscous concrete mixtures, to the latter has been added in a positive mixer an effective amount of an aqueous plastics dispersion based on anionic and hydrolysis-resistant copolymers of ethylenically unsaturated monomers, the minimum film forming temperature (MFT) of which is above the setting temperature of the concrete mixture, preferably above 23.degree. C.

Abstract: There is disclosed a hollow reinforcing element for casting into composites, which in use defines passageways that may communicate to the exterior of the composite and that can serve as conduit arrays in structures formed from the composite. Benefits include superior strength to weight ratios, reduced thermal stresses, suppression of crack propagation, and improved corrosion protection. The hollow reinforcing elements may also be used to provide antennae, drain systems, leveling devices, containment structures and pneumatic levitation of vehicles.

Abstract: A composite concrete pipe in which both the inner and outer surfaces are plastic. The pipe may be formed of any diameter by forming the inner and outer plastic surfaces from helically wrapped interlocking plastic strips to form the diameters desired.

Abstract: A rectangular reinforcing cage is provided for a cast concrete structure having longitudinal registration tubes at each corner of the cage. An outer reinforcing cage surrounds the registration tubes and a coaxial inner reinforcing cage is supported from the outer cage by a plurality of spacers. Each reinforcing cage has a pair of facing C-shaped mats having straight mats overlapping and connected to the bent ends of the "C" to complete each reinforcing cage. Each end of the C-shaped mats have a smoothly curved transition bend joining a portion perpendicular to the main portion of the mat. Each mat has a layer of longitudinal wires connected to a layer of transverse wires. The longitudinal wires being more closely spaced near the end of each mat than in the remainder of the mat with no longitudinal wires in the transition bend of each C-shaped mat. The longitudinal wires are positioned inside each C-shaped mat and outside each straight mat when a reinforcing cage is assembled.

Abstract: A conduit for transporting an oil and water mixture wherein the conduit has an inner surface is substantially hydrophilic and oleophobic. The surface is characterized by a water absorption capacity of greater than or equal to about 8% by weight, and by a contact angle with the oil of greater than or equal to about 120.degree.. The inner surface material may be a silica containing concrete composition or a polymeric coating composition. A conduit having such an inner surface is wetted by water so as to inhibit adhesion of oil to the conduit.

Abstract: A pipe cladding composition is described which is a phosphate ceramic permeating a non-woven fibrous network. The overall thickness of the sheet is between about 5 and about 20 mils. The phosphate ceramic permeates the fibrous network and extends beyond the fibrous network only up to a maximum thickness of about 3 mils across each side of the sheet. The sheets are prepared using wet reaction mixtures which produce phosphate ceramics. These reaction mixtures are mixed and pressed into the non-woven fibrous network which forms a wet sheet that is then cured to provide the cladding material.

Abstract: Iron pipe and other hollow articles are lined with a cementitious mortar containing a quantity of polymer particles and the pipe is rotated about its axis so as to stratify the mortar and develop a polymer rich inner surface that is subsequently cured, dried and heated to the polymer fusion temperature and then coated with a continuous layer of pure polymer.

Abstract: A concrete structure is lined with a statically self-supporting glass shell composed of shell segments which are themselves joined together by sealing strips. In a pipe embodiment of the invention, the shell segments form a ring spaced from the concrete body with the spacing being filled by a backfill mass so that a compressive prestress is provided to the arch shape. When used in a container, the shell may be a laminate of two or more glass layers bonded full surface together.

Abstract: A method for manufacturing multi-dimensionally curved guide rails having tubular cross-sections for passenger and material transportation systems, in which a hose-like plastic tube of any tubular cross-section is bent according to requirements and subsequently filled with a filling compound to stabilize the shape.

Abstract: A prestressed concrete article including overlying the ends of the article and having gasket rings between the article and the end walls. A hardenable medium is injected between the jacket and the concrete article and generates a sufficient pressure so as to outwardly bulge the jacket, drawing the end walls together thereby compressing the gaskets.

Abstract: A fluid-conveying conduit of large cross section, formed by assembling on a laying surface a plurality of prefabricated longitudinal elements placed in sequence and comprising, in transverse section, a lower base and a vault having two lateral edges connected to the base by sealingly joining longitudinal members, which consist of two parallel metallic profiled members rigidly connected to one another by at least one crosspiece and fixed to a slab forming the base of the conduit, and the vault consists of at least one thin wall element and is sealingly fixed by its two lateral edges along two longitudinal profiled members. The invention applies especially to the construction of conduits for conveying fluid under pressure, for example for water conveyance, urban heating or penstocks.

Abstract: A concrete-type composite pipe having a cylindrical concrete layer and a corrosion protective layer formed in an inner surface of the drum mold; in a boundary region between the concrete layer and the corrosion protective layer, an intermediate resin/concrete layer having properties intermediate the concrete layer and the corrosion protective layer.

Abstract: Thrust pipe for disposition in a passage in the ground by advance of the pipe axially through the passage includes a plurality of pipe segments disposed in end-to-end relation one to the other. Each pipe segment includes an inner pipe section having a diametrically enlarged end for telescopically receiving the opposite end of an adjacent inner pipe section. The pipe segments each include an outer pipe section, substantially enveloping a corresponding inner pipe section. The outer surface of the pipe segments is smooth and substantially continuous. Each outer pipe section at one end terminates short of the end of the corresponding inner pipe seciton and is spaced from the outer pipe section of the adjacent pipe segment whereby compressive loadings from thrusting the pipe axially through the passage are carried by the inner pipe sections and not be the outer pipe sections.

Abstract: In a concrete-wrapped pipe having an inner water-impermeable resinous coating, the concrete wrapping is formed with a continuous inner portion covering the resinous coating and a helically slotted outer portion, the helical slot extending at least to the depth of a mesh reinforcement embedded in the concrete. The structure is characterized by the fact that the inner portion of the concrete wrapping is formed with one or more helically extending zones of reduced compressive strength, radially aligned with the helical slot or slots in the outer portion. The helical configuration breaks the continuity of the concrete wrapping in the longitudinal direction of the pipe and, even with pipe of relatively large diameter, enables the wrapping to accommodate limited bending of the pipe.

Abstract: A pipe elbow having a composite ceramic wear liner which is particularly adapted to resist abrasive wear from particulate material conveyed through the pipe elbow. The composite ceramic wear liner is comprised of four series of polyhedron shaped ceramic wear blocks disposed at angularly spaced locations around the circumference of the elbow flow passageway. A mixture of wear resistant particles and binder surrounds the wear bricks and provides an abrasion resistant wear surface along those portions of the pipe elbow which are less subject to abrasive wear. The pipe elbow is provided with a removable cover plate in order to access and replace the series of wear bricks located along the outside center line of the pipe elbow most subject to wear.

Abstract: A structural system for use in bridges, buildings and other structures. The system supports part of its load by tension action and part of its load by arch action. Cables are stretched and anchored between end supports. Lateral compressive elements are placed over the cables and fit over grooves across the bottoms of the elements. The gooves vary in depth. The cables are near the bottom of the elements at the center span and near the top of the elements at the end supports.

Abstract: A plain concrete pipe having an evenly distributed steel wire reinforcement is disclosed, said pipe being suitable for water piping and the like; this pipe being reinforced with a reinforcement constituted by thin wires evenly distributed and arranged in a circumferential pattern and a longitudinal pattern; a method is also disclosed for the manufacture of the pipe on an industrial scale in an efficient and economical manner.