Abstract: Both an apparatus and method for plugging a conduit, such as a tube in the tubesheet of a nuclear steam generator, is disclosed herein. The plugging apparatus generally comprises an inelastically expandable plug that contains a fluid-receiving cavity, and an expansion means including both a source of pressurized hydraulic fluid and a pull-rod member having a piston for advantageously applying both a radially expansive force and a compressive force to the plug at the same time in order to inelastically expand it into sealing engagement with the inner wall of a tube. In the apparatus of the invention, the compressive force exerted on the plug by the pull-rod member not only serves to inelastically deform the plug into a radially expanded shape, but is also used to seal the open end of the plug so that the pressurized hydraulic fluid admitted within the cavity of the plug will not escape.

Abstract: An improved fixing arrangement includes a planar flange having a mounting hole formed through an axial portion thereof, a radially expanded portion being formed in a portion of the peripheral surface of the mounting hole for receiving an annular resilient sealing member; and a pipe having one end provided with an pipe-diameter portion and a radially expanding annular portion. The radially expanding annular portion is engaged with the peripheral edge of the mounting hole which is formed on the back side of the flange to insert the pipe-diameter portion into the mounting hole. In addition, within the mounting hole, the end of the pipe-diameter portion is enlarged or a part of the pipe-diameter portion is radially expanded to press the resilient sealing member and to clamp the radially inwardly projecting peripheral edge of the mounting hole between the radially expanded portion and the enlarged end or radially expanded end portion, thereby fixedly connecting the flange and the pipe.

Abstract: A method of attaching a female element having an annular riveting portion to a panel and the installation apparatus. The method includes driving a punch through the female element into a panel supported on a die member forming an unsupported cone-shaped panel portion in the cavity of the die member. The punch includes an axially extending piercing end which pierces a small opening in the cone-shaped panel portion and an arcuate drawing portion which is driven against and through the panel opening, enlarging the panel opening. The annular riveting portion of the female element is then driven into the cone-shaped panel portion and through the panel opening, drawing the panel portion into a tubular shape engaging the external surface of the riveting portion. Finally, the riveting portion is driven against a center post of the die member, radially outwardly deforming the free end of the riveting portion and forming a mechanical interlock with the tubular panel portion.

Abstract: A liner (12) substantially smaller than the thickness of the tube plate (2) is inserted into the tube (8) so that, while one of its ends is in a region of the tube (8) inside the tube plate (2) and away from the entry face (2a), the other end of the liner (12) is beyond the exit face (2b) of the tube plate. Diametral expansion and roller expanding of the liner (12) are performed in the position which the latter occupies inside the tube (8).

Abstract: An apparatus for securing straight tubes between two tube sheets in a pressure-tight manner, especially in the manufacture of heat exchangers. Tubes are inserted, with play, in bores of the tube sheets. One end of each tube is hydraulically expanded via a pressure medium to thereby press this one end against the associated tube sheet. The one end is secured to the associated tube sheet, preferably by being welded thereto. Each tube is heated in conformity with a prescribed prestress that is to be produced in secured ones of the tube to take into account subsequent operation conditions to push a portion of the non-secured other end of the tube out of its associated tube sheet until a predetermined difference in length between the cold and heated-up states of the tube is pushed out.

Abstract: A method and an apparatus for manufacturing cam shafts in which cam members are held in respective rotatable axially aligned rings by holding members connected within the rotatable rings so that a pipe member cam be inserted through respective aligned holes of the cam members. The rings are individually rotatable so as to rotate the cam members by respetive predetermined angles. After a pipe member is inserted in the holes of the individually rotated cam members, a bulging process device seals respective opposite ends of the pipe member and forces a pressurized fluid into the pipe so as to bulge the pipe to fix the pipe in the respective holes, thereby to form the cam shaft.

Abstract: A method for production of a multi-layer gap-less steel pipe. An inner pipe and an outer pipe are formed from thermomechanically rolled steel strip with high notched bar impact strength by welding. The individual helical welding seam steel pipes of about the same lengths are matched with a difference of less than about one percent between the outer diameter of the inner pipe and the inner diameter of the outer pipe. The matched inner pipe is inserted into the outer pipe and the pipes are mechanically expanded with diameter control to a preset outer diameter of the multi-layer steel pipe. The resulting multi-layer steel pipe has the inner pipe disposed under compression and the outer pipe layer disposed under stress. The presence of a compression stress in the inner pipe provides a means opposed to hydrogen sulfide stress corrosion.

Abstract: A burnable absorber cluster assembly includes a support plate, a plurality of burnable absorber rods, and an improved attachment joint for detachably connecting an upper end of each of the absorber rods to the support plate. The attachment joint includes a plug insert defined on the end of each of the rods, a hollow annular wall extending outwardly from each plug insert, holes defined through the support plate for receiving the plug inserts, and recesses formed in the support plate and connected with the holes therein. Each recess is conical-shaped and extends in flared fashion outwardly from one hole to a maximum diameter greater than the diameter of the hole. The annular wall on each plug insert is deformed into conformity with the shape of one of the recesses for providing an interengaging connection between the insert plug and the support plate in which the plug insert is disposed within the support plate hole.

Abstract: At least one ring (2) of material having a hardness greater than that of the tube (3) and that of the hollow cylindrical component (1) is arranged around the latter in contact with its outer surface. The cylindrical component is introduced inside the tube (3) and then expanded and crimped at least in its part containing the ring of hard material (2), thereby embedding the ring in the cylindrical component (1) and in the tube (3) at the same time.

Abstract: A composite pipe is proposed which is comprised of an aluminum pipe and a lead pipe formed in the aluminum pipe in direct contact with the inner wall of the aluminum pipe. The composite pipe is produced by supplying a lead pipe to a continuous aluminum extrusion machine which can extrude while enveloping a long object, to form an aluminum pipe on the outer periphery of the lead pipe. A heat pipe using the composite pipe is also proposed.This is a division of U.S. patent application Ser. No. 811,164, filed Dec. 19, 1985, now U.S. Pat. No. 4,733,699, issued Mar. 29, 1988.

Abstract: A method of combining a plurality of parts and a structure of a plurality of parts combined by the method, wherein each of the plurality of parts are provided with connecting bores in opposed portions thereof, the plurality of parts are put together in a piled state and a connecting tube is inserted into the connecting bores. An expanding punch is provided for subsequently expanding the connecting tube thereby combining or connecting members to each other.

Abstract: A method and apparatus for belling and expanding the tubes of a plate fin heat exchanger that involves a gripper for gripping the tube during the belling operation and a clamp for clamping a tube sheet during the tension expanding operation.

Abstract: A pair of back-up members (32, 42) are inserted between adjacent projection (4) of a workpiece (2). Openings (36, 46) through the members (32, 42) are aligned with holes (6) through the projections (4). A wedge (54) is driven between the members (32, 42) and forces them against outer surface portions (5) of the projections (4) surrounding the holes (6) and radial end surfaces (9) of bushings (7) positioned in the holes (6). A mandrel (62) is pulled through the bushings (7) and the openings (36, 46) to install the bushings (7). Another embodiment of back-up members (132, 142) has a plurality of openings (136, 146) for use with a workpiece (102) having a plurality of rows of axially aligned holes (106). This embodiment is preferably used with a locator (70) which has two rods (74) for holding the holes (106) and openings (136, 146) in accurate alignment.

Abstract: A coupling sleeve (3) pushed onto the plastic pipe (1) and provided with barbs (3a) is drawn over a driving shoulder against the connecting piece (2) by a union nut (4). The opened-out pipe end (1a) is clamped between a curved end face of the connecting piece (2) and the coupling sleeve (3). Possible leakages caused by the flow of the pipe material are prevented by a spring (6), and the pipe (1) is prevented from turning during assembly by a sliding ring (5). The device used for assembling the pipe connection has grips (13) for fixing the pipe in position with a toggle lock (16) and a press ring (26), which can be displaced in sliding manner on a stop (25) acting as a centering arbor, and can be actuated by a hand lever (31). With only a few manipulations, the coupling sleeve (3) can be pushed onto the centrally held plastic pipe (1).

Abstract: A tube connector comprising a first member and a second member, each member being made from a sheet metal stamping. Each member includes an annular portion, a tubular barrel, and plural legs. The tubular barrel extends from an inner periphery of the annular portion. The legs extend outwardly from the annular portion and are adapted to flex axially so as to facilitate insertion of such member into the tube through one end of the tube. The legs have sharp edges tending to dig aggressively into an inner wall of the tube so as to resist withdrawal and rotation of such member. The tubular barrel of the first member fits within and extends through the tubular barrel of the second member and is crimped at one end so as to secure the tubular barrel of the second member bears at one end agains the annular portion of the first member. The tubular barrel of the first member is internally threaded and consequently deformed so as to fit tightly within the tubular barrel of the second member.

Abstract: An improved cold forging tool to exert radial forces outwardly within a tubular member to forge it into an annular member having a central body with a shoulder on its exterior at both ends and support connecting into one end, a resilient sleeve surrounding the central body, a passage through the central body to communicate between a pressure supply connected to the end of the body and the interior of the resilient sleeve, a support ring surrounding each end of the resilient sleeve and a segmented ring positioned between the central expansion portion of the resilient sleeve and each of the support rings with resilient ring retaining the segmented ring in surrounding relationship to the ends of the resilient sleeve to prevent extrusion of the resilient sleeve during forming of the tubular member. In one form of the tool the resilient packer sleeve is molded on the central body.

Abstract: An assembly for securing a repair sleeve within a damaged pipe, comprising a tubular repair sleeve, and a shape memory alloy element positioned within the sleeve and having a mandrel on each end with at least a portion of each mandrel extending beyond the sleeve at a respective end of the sleeve, arranged so that when the shape memory alloy element recovers, the mandrels are moved towards one another so that each end portion of the sleeve is caused to expand outwardly.

Abstract: A method of forming and installing anti-vibration bars into a tube bundle of a steam generator is disclosed. The tube bundle comprises rows of tubes, each tube carrying a high temperature coolant. Each of the resultant anti-vibration bars has a tubular configuration and is disposed between adjacent rows of the tube bundle for stabilizing the tubes against vibration caused by fluids recirculating at high velocities through the steam generator. The method of this invention comprises the steps of inserting at least one anti-vibration bar between adjacent rows of the tube bundle and applying a pressurized fluid in the anti-vibration, thus expanding the anti-vibration bar to contact the tubes of the adjacent rows and to make a series of indentations therein. Typically, the pressure of the fluid is increased incrementally up to a maximum level set such that the configuration of the steam genrator tubes is not deformed.

Abstract: A method of producing a shaft having plate-like member joined thereto comprises the steps of forming a through hole in the plate-like member, forming an annular groove in the inner surface of the through hole of the member, making the surface of the annular groove rugged by knurling, forming an annular projection on a shaft the outer diameter of the annular projection being substantially equal to or slightly smaller than the inner diameter of the through hole of the plate-like member inserting the shaft into the through hole of the plate-like member so that the annular groove is positioned between both sides of the annular projection supporting the side of the plate-like member and an end portion of the shaft and pressing substantially the whole of the side face of the annular projection of the shaft so that a part of the annular projection of the shaft plastically deforms and flows into the annular groove of the plate-like member, whereby the plate-like member is rigidly joined to the shaft.

Abstract: Method of repairing a steam generator tube by means of a liner, in which the mechanical deformation (19) of the liner (15), by expansion in its end part opposite the expanded end (16) inside the tube plate (11), is located at a limited height, and the parameters of the mechanical deformation (19) are calculated in accordance with the welding parameters subsequently applied. These parameters are determined in accordance with the parameters of the initial mechanical deformation (19) so as to obtain relief of the stresses more particularly in the critical zones (19a, 19b) of the mechanical deformation.

Abstract: A method and apparatus for securing straight tubes between two tube sheets in a pressure-tight manner, especially in the manufacture of heat exchangers. Tubes are inserted, with play, in bores of the tube sheets. One end of each tube is hydraulically expanded via a pressure medium to thereby press this one end against the associated tube sheet. The one end is secured to the associated tube sheet, preferably by being welded thereto. Each tube is heated in conformity with a prescribed prestress that is to be produced in secured ones of the tube to take into account subsequent operating conditions to push a portion of the non-secured other end of the tube out of its associated tube sheet until a predetermined difference in length between the cold and heated-up states of the tube is pushed out.

Abstract: Axially spaced cams and bearing rings mounted on a tube are permanently secured to the tube by circumferentially spaced projections on the tube extending into grooves formed on the inside surfaces of the cams and bearing rings.

Abstract: An improved tube and fin heat exchanger and a method and apparatus for making the same is disclosed. The head exchanger includes spaced end sheets and a stack of plate fins positioned therebetween. Hairpin tubes extend through the end plates and the stack of fins. The tubes are initially sized to loosely fit through the end sheets and fins and are expanded into tight heat exchange engagement therewith during manufacture. The end sheets are accurately positioned a fixed distance apart by a method and apparatus in which the end sheets are held a fixed distance apart during the expansion of the tubes. The bent ends of the hairpin tubes are moved upwardly through the adjacent end sheet and the fins ahead of the expansion bullets to compensate for the shortening of the tubes created by the expansion operation.

Abstract: An elongated tool device adapted for use in installing a tubular sleeve within a tube and forming a pressure-tight seal therebetween. The tool device includes a housing having a reduced-diameter forward extension portion attached to a front cylinder, and containing a rear piston. The front cylinder is attached to a collet having multiple radially expandable fingers and contains a front piston attached to a tapered mandrel which is axially movable within the fingers, and has a forward tapered nose portion to facilitate inserting the tool into a tube. The rear piston is attached to the front piston by an elongated rod. By pressurizing the tool front piston by a hydraulic fluid pressurizing unit, the mandrel is forced forward through the collet fingers to expand the fingers and sleeve tightly into the tube to form the seal joint.

Abstract: An insert for providing a reduced inside diameter for a structural tube, specifically an instrumentation guide tube, of a nuclear fuel assembly. The insert has forming lobes which coact with the structural tube to plastically deform the structural tube and mechanically lock it with respect to grid straps of a grid assembly. The insert also has centering lobes to prevent it from being expanded in other than a coaxial alignment with the structural tube. An expansion tool is provided for sequentially registering with and expanding sequential forming lobes in a simplified manner whereby all of the operations necessary to assemble the structural tube in the fuel assembly can be easily and accurately performed.

Abstract: A rod mounting system for mounting expander rods in tube expander machines is disclosed. The mounting structure includes an opening in a header sized to receive the end of a mounting rod. A key extends into the opening from one side thereof. The rod end is provided with two longitudinally extending keyways and a peripheral groove. The first keyway extends from the end of the rod to an end face aligned with the peripheral groove. The second keyway extends from a location spaced from the end of the rod in both directions beyond the peripheral groove. The rod is installed in the header by longitudinal movement in an installation and removal orientation in which the key is aligned with the first keyway. When the rod engages the inner end of the first keyway, it is rotated to position the second keyway and the key in alignment. In such orientation, the rod is locked within the header for movement between two limits of longitudinal movement.

Abstract: An apparatus for joining two tubular members together at a subsea location wherein one of the tubular members has internal grooves and the second tubular member is sufficiently small to slide into the first tubular member and the first tubular member has an external flange suitable for connecting to a flowline, which apparatus includes a tubular mandrel having means for connecting to said first tubular member, a resilient sleeve surrounding said mandrel and adapted to be positioned within said second tubular member, volume compensating means positioned within each of said grooves and testing means carried by said mandrel to allow testing of the joint while the mandrel is still in position after forming.

Abstract: An existing underground sewer or other pipe is renovated by rupturing and radially expanding the pipe and installing a replacement pipeline within the ruptured pipe. The pipe is ruptured and radially expanded by introducing a plurality of radially expandable tubular members into the pipe so as to form a liner. Each member is then radially expanded so that the liner engages with and then ruptures the portion of the pipe adjacent thereto. The tubular members may be radially expanded by inflating a bag within the confines of the members.

Abstract: An improved process by which heavy duty aluminum ladder rungs are easily manufactured with the central stepping portion of the rung itself possessing qualities of exceptionally high yield strength, while the ends of the ladder rung are easily formable such that they are readily crimped and secured to the end rail or stile during the ladder assembly process--without cracking or fracturing. In order to maintain high strength at the central portion of the ladder rung while providing for adequate deformability at the ladder rung ends, the invention uses a selective localized heat treating process whereby high frequency induction heating is applied selectivley to the ladder rung ends prior to collar and upset formation.

Abstract: An apparatus for tension expanding a plate fin heat exchanger to provide a heat exchanger with bells of the same form and dimension and then expanding the tube into contact with the tube sheets and hairpin tubes while the bells are clamped to prevent the hairpin tubes from moving.

Abstract: A union joint assembly comprising a union fitted around and end of one pipe, a nut fitted around an end of the other pipe and adapted to be screwed to the union for joining the ends of pipes, and a retaining means for retaining the union on said one pipe against axial displacement with respect to the one pipe. The retaining means comprises an annular recess opening to an axial central through-hole and an annular ridge projecing radially outwardly from the outer periphery of said one pipe and fitted in the recess.

Abstract: A method for preventing corrosion of an expandable mounting element which involves introducing a sealing composition into a mounting hole of a support structure first to fill the hole about half-way, then driving an expandable mounting element into the half-filled hole to displace the sealing composition initially against the base of the mounting hole and then up along the surface of the expandable mounting element until the excess emerges out of the mounting hole. A compressible impact device, which has an upper and lower part and a spring part fixed therebetween, is arranged so that an impact tool can be driven against the upper part to fully drive the expandable mounting element into the mounting hole, effecting a sealing compaction in correspondance with the pressure exerted by the spring part. All gaps and cracks are thereby sealed against corrosive media.

Abstract: A fabricated camshaft having individual lobes mounted on tubular collars that are in turn mounted on an internal tubular member that is expanded between the collars to form bearing journals for the camshaft.

Abstract: This invention is directed to a method of working the free end of heat exchanger tubes, and particularly the formation of braze cups, with the heat exchanger tubes in situ relative to the heat exchanger core with the method including the step of utilizing centering tooling positioned about a tube expansion rod to assure that the braze cup is centered relative to its respective tube axis.

Abstract: This invention relates to a method of forming hollow, box-section, frame members which include localized reinforcement. The frame members are produced by fitting a sleeve about a tube, deforming the tube and sleeve to avoid the occurrence of frictional drag in a final die, and then expanding the tube and sleeve in a final die to form the hollow, box-section, frame member. The expansion is achieved by application of an internal pressure within the tube.

Abstract: The axially movable pressure plate of a friction clutch for motor vehicles is non-rotatably secured to the housing by a set of leaf springs each of which has an end portion overlying that surface of the pressure plate which faces away from the clutch plate. The end portion of each leaf spring has an opening in register with the open end of a blind bore in the surface of the pressure plate. Such end portions of the leaf springs are permanently fastened to the pressure plate by tubular connecting elements having (a) enlarged end portions overlying those sides of the leaf springs which face away from the pressure plate and (b) main portions which extend through the respective openings and into the registering blind bores and are radially expanded into pronounced frictional engagement with the pressure plate.

Abstract: Method of fastening drive elements on a hollow shaft, which comprises:pushing n drive elements with a thickness a over a hollow shaft, retaining the drive elements at mutual spacings b and in respective desired azimuthal positions by means of holding devices;providing active sections of a material with a given limit of elasticity, a length c, mutual spacings d and being bounded by sealing lips on a hydraulic expanding device so that n(a+b)=n(c+d), pushing the hydraulic expanding device into the hollow shaft; andapplying a pressure through the hollow shaft to the active sections stressing the material of the active sections radially beyond the given limit of elasticity.

Abstract: A spacer sleeve is installed within an instrumentation tube of a nuclear fuel assembly comprising two end nozzles connected by tie rods and a plurality of fuel rod supporting grids distributed at axial intervals along the tie rods. The instrumentation tube has a first end received in an initially blind bore formed in one of the end nozzles and communicating with the outside by a coolant restriction.

Abstract: A blind fastener is provided for connecting two workpieces together, comprising an internally threaded fastener body and an externally threaded stem passing in threaded engagement therewith. A drive nut is mounted on the stem in contact with the fastener body for preventing rotation thereof upon turning of the stem to install the fastener. The outer end of the stem has a cap nut to enable turning of the stem. Both the drive nut and cap nut are engaged by wrench components of an installation tool to cause turning motion of the stem relative to the fastener body to deform a sleeve around the fastener body into contact with one surface of the two workpieces. Although the fastener may vary in size depending upon the nature of the two workpieces to be connected together, the outer dimensions of the drive nut and cap nut remain constant for all fasteners regardless of differing stem diameters of different size fasteners.

Abstract: A blind fastener of the type having a fastener body, a threaded stem and a sleeve is provided with a deformable drive nut in abutting contact with the fastener body to provide a positive mechanical engagement between the abutting surfaces of the two elements. The underside of the drive nut has an annular ridge made of a deformable material adapted to deform into indentations in the outer surface of the fastener body. The positive mechanical engagement between the two elements minimizes the build-up of tensile load applied to the stem during setting of the fastener.

Abstract: A method and apparatus for belling and expanding the tubes of a plate fin heat exchanger that involves a gripper for gripping the tube during the belling operation and a clamp for clamping a tube sheet during the tension expanding operation.

Abstract: A self crimping connection for inner and outer members and the method of making the same includes providing the inner member with stepped cylindrical exterior walls defining an outboard wall of reduced diameter relative to an inboard wall with an annular groove in the outboard wall; providing the outer member with a stepped bore defining an internal outboard wall and an inboard wall to slidably receive the outboard and inboard walls, respectively, of the inner member, with an annular groove in the outboard wall of the outer member; a first bushing encircling the outboard wall of the inner member and a second bushing encircling the outboard wall of the outer member, with each of the first and second bushings having a body portion and a crimp collar portion, the arrangement being such that as the inner member and first bushing are axially pressed into the outer member and its associate second bushing, the crimp collar portion of the first bushing is crimped into locking engagement into the annular groove in the

Abstract: A cam shaft made from lobes having irregularly shaped apertures spaced along the longitudinal axis of a hollow tubular shaft. The method of making the cam shaft includes the steps of: inserting a hollow tubular shaft through the apertures of a plurality of the lobes axially and radially with respect to the longitudinal axis of the shaft. The method is characterized by flaring at least a first end of the shaft and backing the exterior of the first flared end to prevent axial radial movement thereof. In addition, a plug means is inserted into fluid sealing engagement with the interior of the first flared end to sandwich the flared end against the backing of the exterior thereof. The hollow shaft is filled with liquid and the opposite ends of the shaft are clamped between the plug means at the first flared end and a fluid sealing means at the opposite end of the hollow shaft. Hydraulic force is then applied to the interior of the shaft to expand the hollow shaft into engagement with the apertures of the lobes.

Abstract: A plural-chambered, gravity-activated dispensing device that incrementally dispenses two or more flowable products at a substantially constant, predetermined ratio. In one preferred embodiment of the present invention, an inner container is positioned within an outer container, each container defining a chamber adapted to contain a flowable product, and having a discharge opening therein. An empty third container is sized and positioned within the inner container to impose on the inner chamber's pouring characteristics an effect similar to that imposed on the outer chamber's pouring characteristics by the inner container to thereby achieve a substantially constant dispensing ratio between the pourable products dispensed therefrom. In another particularly preferred embodiment, the effect of the third empty container mentioned above is superimposed on the inner container's shape and position within the outer container, thereby eliminating the third empty container.

Abstract: A method of securing tubes between tube sheets of a heat exchanger, with the tube sheets being interconnected via a housing. The tubes and/or the tube sheets of are made of a steel that has to be annealed after a welding process. To be able to provide a stress-free connection between the tubes and the tube sheets, and to enable simple repair of the tubes, the length of at least one end of each tube is extended by welding thereto a tubular piece that is made of a material that can be welded without subsequent thermal treatment being required. Sleeves that extend the length of the holes in the tube sheet are welded onto the outer surface of at least one of the tube sheets. At least the free end of each sleeve is made of a material that can be welded without subsequent thermal treatment being required. One end of each tube, if such end is not provided with a tubular extension, is welded onto a tube sheet.

Abstract: A method and apparatus for expanding in compression a portion of a plate fin heat exchanger up to a tube sheet and then gripping the expanded portion of the tube end to expand the remainder of the tube in tension and then unclamping and belling the end of the tube at a single station.

Abstract: Conventional joints between a fluid line and a body of a fluid injector are typically threaded or brazed. Such threaded joints are sometimes too bulky for certain engine compartments of limited space and such brazed joints are sometimes difficult to make with repeatable high quality.The present invention provides a relatively compact and inexpensive sealed joint for a fluid injector which includes a housing, a body, and a fluid line. The sealed joint is solely formed by an interference fit directly between an end portion of the fluid line and both the housing and an end portion of the body.

Abstract: An insert for providing a reduced inside diameter for a structural tube, specifically an instrumentation guide tube, of a nuclear fuel assembly. The insert has forming lobes which coact with the structural tube to plastically deform the structural tube and mechanically lock it with respect to grid straps of a grid assembly. The insert also has centering lobes to prevent it from being expanded in other than a coaxial alignment with the structural tube. An expansion tool is provided for sequentially registering with and expanding sequential forming lobes in a simplified manner whereby all of the operations necessary to assemble the structural tube in the fuel assembly can be easily and accurately performed.

Abstract: A riveting or self-fastening element such as a stud for permanent attachment to a panel preferably having a preformed panel opening, including the method of attachment and the panel assembly. The self-attaching element includes an annular barrel portion having a conical external surface which is press fitted in the panel opening to deform the panel opening and form a mating conical internal surface preventing further penetration of the fastening element into the panel. The free end of the barrel portion, which is preferably cylindrical, is simultaneously deformed outwardly in a die member having an annular die cavity, forming an annular rim which is U or hook-shaped in cross section, wherein the free end is biased against the panel preventing pull-out of the fastening element. The fastening element, method of attachment and panel assembly is particularly adapted for relatively thick metal panels, including panels having a thickness greater than 0.1 inches.

Abstract: Disclosed is a pipe repair sleeve apparatus. There is a draw means having expanding means on either end of the draw means. There is also an annular repair sleeve. The draw means is contained within the sleeve with at least a portion of each of the expanding means protruding outside of the sleeve. Then, the repair sleeve assembly is inserted within the damaged pipe. The draw means urges the expanding means toward one another and inwardly of the sleeve so that opposed ends of the sleeve are expanded outwardly into engagement with an inside diameter of the damaged pipe. Preferably, the draw means is made from a material which is a shape memory alloy. Also disclosed is a method of repairing a damaged pipe. This method specifies the steps necessary for installing the pipe repair sleeve apparatus.