Abstract: The invention relates to a machine for wave soldering or tinning comprisinga solder reservoir (9);means that can form at least one solder wave with a so-called laminar form (8b);a conveyor system (2) that can bring a piece (1) to be soldered or tinned into contact with said laminar wave; andmeans for injecting (12) a gas in the vicinity of the wave;characterized in that the said injection means includes an injector located in a position adjacent to and downstream from the wave and provided with a wall (17) facing the solder wave, wherein the wall of the injector has at least a first group (15) of openings positioned so as to provide a first gas jet directed toward the flat surface of the solder wave.

Abstract: Screen printing and chip mounting are executed in a dry air atmosphere to prevent generation of solder balls due to absorption of moisture by a flux ingredient of paste solder. Screen printing of the solder on a board takes place in a space which has the board, a printing screen and a squeegee arranged therein and is formed therein with a dry air atmosphere having a pressure slightly higher than that of an atmosphere outside the space. Likewise, mounting of a chip on the board is carried out in a like space. Also, a reflow step is executed in a reflow oven kept at a dry air atmosphere.

Abstract: Flexible connectors having substantially vertical conductive legs allowing the connectors to accommodate deflection in the lateral directions (x-y directions in the plane of the connectors) induced by CTE mismatches between a chip and a substrate during thermal cycling of the chip. The connectors also accommodate deflections in the vertical direction (z direction--perpendicular to the plane of the connectors) which may be caused by connection to a substrate. Such substantially vertical leg features are formed using projection lithography, such as projected x-ray or ultra-violet ("UV") radiation, to selectively expose a photoresist layer such that the substantially vertical metal features may be formed by plating or etching. The sacrificial layer may be in the form of an array of posts, such that "stool-like" post connectors are created, or may be in the form of an array of apertures, such that "basket-like" receptacles or sockets are created.

Abstract: Volatile organic components are controlled in electronic component assembly processes to prevent deposits on finished circuit boards and the like. The method of controlling the components in a machine having a plurality of enclosed heating zones followed by at least one cooling zone containing gas, and a conveyor for passing circuit boards therethrough on a conveyor path, comprises the steps of removing a portion of gas from at least one of the heating zones, cooling and filtering the portion of gas remote from the heating zones and the cooling zone to condense at least some of the volatile components in the portion of gas, and returning the cooled and filtered portion of gas to at least one other zone of the heating zones and the cooling zone.

Abstract: This invention concerns a containment box disposed around a welding head (1) and including a fixed frame carrying a fairing (16) modeled to the shape of the element (3) to be welded, a cover (9) sliding on the frame (10), and a bell with spherical boss (7) integral with the welding head (1) which slides and rotates in a vertical sleeve (8) traversing the cover (9). All the movements of the welding head (1) are therefore permitted which makes it possible to have complicated welding trajectories. Gaskets (15, 17) are provided.

Abstract: A protective device for welding a seam between a pair of workpieces has a flexible metallic band extending along the seam, spaced from surfaces of the workpieces, and having longitudinal edges on which are carried respective elastomeric heat-resistant strips extending the full length of the band and engaging the surfaces of the workpieces. A flexible ceramic band is provided between the elastomeric strips on the metal band between same and the surfaces. The band has a face turned toward and spaced from the surfaces and forms with the surfaces at the seam a chamber extending along the seam.

Abstract: An apparatus and method are available for detecting the presence of inert gas in an enclosure isolating one side of selected weld structures being joined during welding operation. The system and method include using an inert gas detector relying upon an electric filament positioned in a separate containment connected to the first containment in order to determined whether the required purity level of inert gas has been achieved in the weld enclosure.

Abstract: In one aspect, a device for attaching a component to a circuit board is provided, comprising a circuit board held in a holder and a contact heater that heats the component on the circuit board by contact and by conducting heat through the component. In a further aspect, the contact heater is in a wand which is manually moved onto the component. In another aspect, the invention provides a method for attaching a component to a circuit board, comprising the steps of gripping the component with a contact heater; placing the component on the circuit board; and heating the component on the circuit board by contact, wherein heat conducted through the component melts solder under the component and attaches the component to the circuit board.

Abstract: An apparatus comprises a sputter cleaning device, an alignment device operable in atmospheric condition and a heating and soldering device in the form of a belt furnace operable in non-oxidizing or reducing environment. Instead of the sputter cleaning device, a mechanical polishing or cutting device can be used to clean a surface of solder or a member to be bonded or a solder ball plated with gold may be used. An alignment between two members to be bonded is provided by an alignment mark means which comprises a protrusion on a surface of one member and a complimentary recess formed at a center portion of a protrusion means formed on a corresponding surface of the other member.

Abstract: An inert gas air horn distribution device employs a labyrinth with a baffle to clean the nitrogen gas used to deposit flux on circuit boards before wave soldering operations. The baffle diverts the gas flow causing heavier flux particles to collect in the labyrinth while the lighter gas exits for use in depositing flux on the circuit boards. The labyrinth cleans the gas thereby keeping the knife clean which produces more uniform results with less maintenance.

Abstract: A purge block including a first and second first diameter disk constructed from a substantially rigid material; a resilient disk having a second diameter larger than the first diameter concentrically aligned and secured between the first and second first diameter disks; at least one vent hole formed through the first and second first diameter disks and the resilient disk in a manner to form a pathway through the first and second first diameter disks and the resilient disk; and a positioning mechanism protruding from one of the first and second first diameter disks. The resilient disk is preferably constructed from a heat resistant material. The positioning mechanism is preferably a handle or centrally oriented flexible member attachment device.

Abstract: A gas lens assembly for an arc welding torch includes a lens body having a rearward end and a forward end, a passage through the lens body from its forward end to its rearward end for receiving an electrode therethrough and for permitting flow of an inert gas in a forward direction in the passage. A lens housing is secured to the lens body and defines a chamber around a forward end portion of the lens body. One or more openings in the forward end portion of the lens body enable the inert gas to flow from the passage into the chamber. The gas lens assembly further includes a flow control device associated with the housing through which said inert gas is adapted to flow in a forward direction. The flow control device controls the flow of the inert gas therethrough so that the gas exists the flow control device as a laminar stream of gas moving in a forward direction. The laminar stream is adapted to blanket a weld puddle during a welding operation on a workpiece.

Abstract: A soldering device includes a solder vessel for containing a molten solder, solder ejecting nozzle disposed in the solder vessel for upwardly ejecting the molten solder to form a solder wave thereabove, a cover plate covering the vessel and having an opening such that the solder wave can pass therethrough, a nozzle forming body provided adjacent at least one side of the solder wave to define a thin space between the nozzle forming body and the cover plate, and a gas feed conduit connected to the nozzle forming body for feeding a gas to the thin space, so that the gas is jetted through the thin space and flows toward the solder wave.

Abstract: A system is disclosed for forming metal tubing and, more particularly, brake tubing. The system includes a mill for rolling a metal strip into a tube so that at least a portion of the strip overlaps itself. The strip is then brazed so that the overlapping portions of the strip fuse together and form the tube. Thereafter, the tube passes through a cooling tunnel which cools the tube to a temperature such that the tube can be coated with a corrosion resistant material, such as a zinc based material. An inert gas, such as argon, and/or a reducing gas, such as hydrogen, is introduced into the cooling tunnel to prevent or remove oxidation of the tubing as it passes through the cooling tunnel.

Abstract: High frequency electrical discharge or nonpolar discharge using microwaves is generated in a gas that is introduced into a gas duct formed by a dielectric material, such as glass or ceramic. Surface treatment is applied to components, which are under atmospheric pressure, by exposing them to the gas flow containing the active species generated by the above mentioned electrical discharge. The components are soldered before, during, or after the application of this surface treatment. The surface of the components is exposed to the active species by either directly exposing the components to the electrical discharge, or by directing the reactive gas flow containing the active species at the component surfaces. By selecting an appropriate gas for generating the active species, it is possible to improve the wettability of the surface of the component to be soldered, or to remove organic substances or oxide film surfaces.

Abstract: Wave soldering or tinning machine comprising:a solder reservoir;a means that forms at least one solder wave having a laminar form and including a flat surface;a means for bringing a piece to be soldered or tinned into contact with the laminar wave; andmeans for injection of a gas in the vicinity of the wave comprising an injector located in a position adjacent to and downstream from the wave and provided with a wall facing the solder wave, wherein the wall has at least a first group of openings positioned so as to produce a first gas jet directed toward the flat surface of the solder wave.

Abstract: A method for wave soldering a circuit having two or more faces comprising the steps of:(i) passing at least one initial gas mixture comprising at least one of an inert gas, a reducing gas and an oxidizing gas into at least one apparatus for forming excited or unstable gas species;(ii) converting the at least one initial gas mixture into at least one primary gas mixture comprising excited or unstable gas species and substantially free of electrically charged species;(iii) treating each of the two or more faces of the circuit with the at least one primary gas mixture at a pressure close to atmospheric pressure; and(iv) contacting the two or more faces of the circuit with at least one wave of a liquid soldering alloy.

Abstract: The present invention provides a reflow apparatus and method effective to make constant the internal gas flow direction in a heating section within a reflow furnace. A circulating gas path is formed in a heating unit which collects and causes the gas to flow from a sirocco fan, up the rear side of the heating unit and then down towards a circuit board moving along a transfer path at the front side of the heating unit. Moreover, a plurality of straightening plates are arranged above the transfer path of the heating unit so as to guide the hot gas, which is flowing forwardly downwardly toward the circuit board moving along the transfer path. A blow-down nozzle is provided and includes a plurality of plates aligned in rows in the transferring direction of the circuit boards. The plates have an inverse U-shaped cross section. The blow-down nozzle is arranged below the straightening plates to cause the vertical hot gas flows to flow uniformly over the whole surface of the circuit board.

Abstract: An apparatus and method for soldering components to a circuit board. The apparatus includes a conveyor in a tunnel for transporting the board through a preheat zone, molten waves of solder including a turbulent wave and a laminar wave, and a cool down zone through which the board passes upon exit from the laminar flow wave of the solder wave. The improvement comprises at least one distributing manifold mounted in the tunnel having an inlet port for receiving a cold gas under pressure and at least one outlet nozzle for directing the cold gas to the circuit board, thereby rapidly cooling the circuit board and the components.

Abstract: A castellated nozzle for connecting a plurality of microelectronic leads to an associated plurality of contact pads and method of using the same. The castellated nozzle includes a body having a plurality of castellations protruding therefrom, with each of the castellations having a contact surface thereon. A channel is formed adjacent to at least one castellation of the plurality of castellations. An opening extends through the body for introducing a heated gas therein. The contact surfaces of the plurality of castellations are aligned to a respective plurality of leads. Typically, the castellated nozzle includes a first plurality of castellations forming a first row and a second plurality of castellations forming a second row.

Abstract: An apparatus for providing inert gas to a desired location for a welding operation is provided. The apparatus includes a gas feed line and structure for mounting the feed line to extend in a first direction in a pipe. A gas locator tube communicates with the gas feed line to direct inert gas from the gas feed line in a second direction, different from the first direction, towards a pipe joint to be welded. The locator tube is capable of continually directing inert gas in the second direction as the pipe is rotated during a welding operation.

Abstract: A heating device used in a bonding apparatus including a cover which is provided on a heating body so as to cover a guide groove which guides lead frames; and gas grooves are formed in the heating body so as to run along the guide groove, and an inert gas is supplied into the gas grooves so that the inert gas prevents the entry of air from the joining surfaces of the heating body and cover.

Abstract: A solder reflow convection furnace employing flux collection and heating to minimize flux and solvent build up and gas densification to reduce input gas flow is disclosed. As solder melts in the furnace, an effluent of vaporized flux is driven off and can condense on cooler components. To minimize such condensation, the gas is directed through a cooling system in which the flux condenses, and the cooled, cleaned gas is directed into the furnace's product cooling section. In another embodiment, in which the gas in the furnace is recirculated, a cooling coil is located upstream of the recirculating gas mover to heat the primary gas. The vaporized flux condenses on the cooling coil, which can be readily removed and replaced. In another aspect of the invention, when the furnace employs a gas amplifier, the recirculating gas is cooled prior to reentry into the heating chamber, which increases its density and removes flux by condensation.

Abstract: A vestibule for part entry or exit from a flow through type of braze furnace in which no substantial physical barrier is necessary to prevent air exchange between the vestibule and the outside. A controller burner within the vestibule continually burns oxygen that does leak in, sensing whether combustion is complete trough the use of an analyzer in an exhaust stack. In addition, a neutral gas injector within the vestibule chamber maintains a near net zero pressure balance in order to minimize, though not prevent, ingress leakage. Parts can therefore enter the door freely without dragging through the impediment of a physical barrier.

Abstract: A weld spring clip used to tack weld two pipes together using a tungsten inert gas welder and a shield gas includes a reflector that can be inserted within a weld seam using a handle. The reflector, which is attached to an arm and a handle, is positioned beneath the desired weld site on the interior of the pipes. The handle biases the clip in place on the pipe at the seam, and a point on the end of the reflector assists in aligning the reflector at the seam. In position, the reflector reflects the shield gas toward the interior of the weld site. By reflecting the shield gas, oxidation along the interior surface of the weld site is prevented, and the need for a back gas is eliminated.

Abstract: A reflow apparatus includes a reflow furnace. A transfer device holds and transfers printed circuit boards with to-be-reflowed electronic components thereon from an inlet to an outlet of the furnace within the furnace. A plurality of adjusting/circulating sections separate an ambient gas for heating the printed circuit boards into predetermined temperature regions in the furnace in which the ambient gas is circulated in a heated state. A feed port is formed in the furnace to feed the ambient gas into the furnace under pressure. Residence parts each provided between adjacent adjusting/circulating sections regulate the amount of the ambient gas when the ambient gas, after having been sent to and heated in the adjusting/circulating section adjacent to the feed port, is circulated and sequentially moved to the adjusting/circulating sections at the inlet or the outlet and finally flows out through the inlet or outlet into atmosphere.

Abstract: A reflow soldering system includes a reflow station with one or more soldering containers. Each container includes a base and a cover reciprocable to either open or close the container. When open, the container receives a printed circuit board/electrical circuit component assembly for reflow soldering, or permits the exit of such assembly after soldering. When closed, the container provides a fluid-tight seal between the chamber inside and the immediate outside environment. Container opening and closure are synchronized with an input conveyor providing assemblies to the container and an output conveyor removing the soldered assemblies, both of which are operated by a control system at a controlled rate of speed. When the container is closed, its internal environment is precisely controlled through heating elements in the container and several conduits for supplying air (heated if desired), for supplying an inert gas, and for drawing a vacuum.

Abstract: A tunnel-type processor for solder flow application of solder connections to circuit elements on a circuit board. The boards with deposited solder are passed through a heating zone and a cooling zone, on a platen. Heated or cooled gas is injected into the zones to maintain a suitable temperature along with the platen. A housing with an exhaust conduit encloses the platen and limits flow of gas from one zone into another. An optional top manifold can be provided to discharge gas into a respective zone.

Abstract: The present invention provides a reflow apparatus and method effective to make constant the internal gas flow direction in a heating section within a reflow furnace. A circulating gas path is formed in a heating unit which collects and causes the gas to flow from a sirocco fan, up the rear side of the heating unit and then down towards a circuit board moving along a transfer path at the front side of the heating unit. Moreover, a plurality of straightening plates are arranged above the transfer path of the heating unit so as to guide the hot gas, which is flowing forwardly downwardly toward the circuit board moving along the transfer path. A blow-down nozzle is provided and includes a plurality of plates aligned in rows in the transferring direction of the circuit boards. The plates have an inverse U-shaped cross section. The blow-down nozzle is arranged below the straightening plates to cause the vertical hot gas flows to flow uniformly over the whole surface of the circuit board.

Abstract: In order to remove oxide film and contamination film on members to be bonded by soldering and solder material therefor corresponding to variation of thickness thereof by sputter-etching in a fluxless bonding method and apparatus therefor, substance emitted from the solder material under sputter-etching using atom or ion is detected and determined whether it is from the solder material or from the oxide film thereon. The sputter-etching is controlled on the basis of the determination to remove the oxide film. Then, the members are aligned in oxidizing atmosphere and soldered in non-oxidizing atmosphere.

Abstract: A fluxless soldering sample pretreating system includes a sample chamber having an opening therein and a sample holder. A sample chamber extension extends outwardly from the opening to define a passageway from the sample chamber extension, through the opening, and into the sample chamber. A fluorine-containing gas is supplied into the sample chamber extension. Am energy source such as a microwave oven surrounds the sample chamber extension. The microwave oven produces microwave energy in the sample chamber extension to form a plasma therein and dissociate the fluorine-containing gas into atomic fluorine. A perforated aluminum plate extends transversely across the passageway and blocks the plasma from traversing the passageway from the sample chamber extension into the sample chamber, while allowing the atomic fluorine to traverse the passageway from the sample chamber extension into the sample holder.

Abstract: The invention relates to a method for soldering electronic components to printed circuit boards or other elements to be connected by soldering, as well as suitable continuous soldering systems. The use of electronic modules, designed in the form of printed circuit boards populated with pluggable, mountable, or surface-mountable electronic components (Surface Mounted Devices, SMDs), which must be then soldered, is growing steadily. To manufacture these modules, suitably prepared printed circuit boards are populated with the corresponding components, the latter are held in place possibly with an adhesive or soldering paste in preparation for the soldering process, and finally the printed circuit boards and the components are connected together permanently and conductively by a soldering process. This soldering process is performed under low pressure and under the plasma action of a special process gas.

Abstract: The present invention provides a reflow apparatus and method effective to make constant the internal gas flow direction in a heating section within a reflow furnace. A circulating gas path is formed in a heating unit which collects and causes the gas to flow from a sirocco fan, up the rear side of the heating unit and then down towards a circuit board moving along a transfer path at the front side of the heating unit. Moreover, a plurality of straightening plates are arranged above the transfer path of the heating unit so as to guide the hot gas, which is flowing forwardly downwardly toward the circuit board moving along the transfer path. A blow-down nozzle is provided and includes a plurality of plates aligned in rows in the transferring direction of the circuit boards. The plates have an inverse U-shaped cross section. The blow-down nozzle is arranged below the straightening plates to cause the vertical hot gas flows to flow uniformly over the whole surface of the circuit board.

Abstract: There is provided a reflow soldering apparatus for soldering electronic parts to a circuit substrate by blowing various inert hot gases of a desired density and temperature. A device for detecting whether or not a processing object is being conveyed into the apparatus is provided, so that the amount of inert gas to be supplied and the gas blowing speed are decreased when no processing object is present inside the apparatus. As a result, the amount of gas which flows out is made small, and a decrease in the temperature of the apparatus can be prevented. When the processing object is conveyed into the apparatus, the amount of supplied gas is increased so as to obtain a sufficient gas density. Thus, it is possible to prevent solder from being oxidized, and satisfactory solderability can be obtained.

Abstract: A thermo-compression tool incorproated in an assembly/disassembly system melts solder films of conductive leads of an electric circuit componet for bonding the conductive leads to pads of a circuit board, and nozzles blow high-temperature nitrogen gas to the conductive leads during the bonding work for preventing the solder films from oxidization.

Abstract: A method and apparatus for use in welding pipe. The apparatus includes means for viewing the interior of the pipe, means for establishing a predetermined atmosphere in the weld zone and means for clearing liquid from the interior of the pipe.

Abstract: A wire bonding apparatus has a sealed casing having an opening which can be opened and closed, a device for gas-tightly dividing the casing into first and second chambers, a sealing device that is movable for communicating the two chambers with each other, a device for supplying an inert gas into the first chamber, a device for supplying oxygen gas or ozone gas into the second chamber, a device for connecting an electrode of the substrate to an electrode of the semiconductor chip via the wire in the first chamber, a device for generating glow discharge in the second chamber, and a device for transporting the substrate between the first and second chambers. Wire bonding is immediately performed after impurities are removed from the electrodes by electrical discharge.

Abstract: An apparatus and method for purging reactive gases from the vicinity of a molten weld during the welding process, having particular application to the welding of industrial process piping systems and pipelines, especially stainless steel and other alloy pipelines. A system is disclosed for boosting purging speed and efficiency by providing a multidirectional flow of purging gas adjacent to the interior walls of the pipe sections being joined. The rate of purge gas flow is automatically adjusted in response to changing gas pressures in the vicinity of the progressing weld.

Abstract: A circuit board is wave soldered as it is carried by a conveyor through a solder wave established in a solder reservoir. Disposed on both sides of the solder wave are gas plenums which discharge shield gas. The gas plenums include orifices for directing shield gas (i) at high velocity toward the solder wave to protect the solder wave with an atmosphere of shield gas, and/or (ii) upwardly toward an underside of the circuit board to strip entrained air therefrom. The solder wave is generated by a pump driven by a drive shaft that extends downwardly into the solder reservoir. An upper portion of the drive shaft is surrounded by a stationary hollow sleeve which projects into the solder reservoir to restrict the churning of the solder during rotation of the drive shaft. A shield gas is introduced into the sleeve to inert the solder being churned. An enclosure is positioned above the solder reservoir having an inlet and an outlet through which the circuit boards are conveyed.

Abstract: A circuit board is wave soldered as it is carried by a conveyor through a solder wave established in a solder reservoir. Disposed on both sides of the solder wave are gas plenums which discharge shield gas. Each gas plenum includes a top wall, a side wall, and a bottom wall. The side wall is spaced horizontally from the wave, and the bottom wall is submerged within the solder. The side and (optionally) top walls include orifices for directing shield gas (i) at high velocity toward the solder wave to protect the solder wave with an atmosphere of shield gas, and (ii) upwardly toward an underside of the circuit board to strip entrained air therefrom. Instead of being submerged within the solder, the bottom wall could be spaced above the solder and provided with orifices to emit shield gas downwardly between the plenum and solder reservoir to create an inert atmosphere above the solder.

Abstract: The invention relates to a soldering apparatus comprising: a soldering chamber; transporting means for transporting the objects to be soldered through the soldering chamber; and heating means for heating the objects to be soldered in the soldering chamber, wherein the heating means are formed by means for feeding heated gas to the chamber. A simple device is thus obtained which heats uniformly. Such an apparatus can be embodied in both closed and open form. According to one of the preferred embodiments the means for feeding heated gas are formed by at least one heating unit, wherein the heating units are each formed by a fan and at least one heating device, for instance an electrical heating filament, connected forwardly thereof. Cooling units can also be used.

Abstract: A cover or shroud extends over a solder reservoir and has a slot for a solder wave to protrude therethrough. Gas is provided to blanket the solder wave and the shroud is positioned to reduce solder from contacting elements that are conveyed through the solder wave. The devise comprises a solder reservoir having at least one solder nozzle projected therefrom, a pump for forming a solder wave from the nozzle, a cover for covering at least a portion of the reservoir containing the solder wave, the cover having a longitudinal slot for the solder wave to pass therethrough and contain solder splatter caused by the solder wave falling into the solder reservoir. A gas supply provides gas under the cover and also provides a gas blanket over the solder wave, and a conveyor moves the element in a predetermined path over the cover ensuring at least a portion of the element passes through the solder wave.

Abstract: An apparatus and method for purging reactive gases from the vicinity of a molten weld during the welding process, having particular application to the welding of industrial process piping systems and pipelines, especially stainless steel and other alloy pipelines. A system is disclosed for boosting purging speed and efficiency by providing a multidirectional flow of purging gas adjacent to the interior walls of the pipe sections being joined. The rate of purge gas flow is automatically adjusted in response to changing gas pressures in the vicinity of the progressing weld.

Abstract: A shield protects the back side of a molten and solidifying weld on a structure being welded from the deleterious effects of ambient gases, such as oxygen and nitrogen. The shield is in the form of a continuous tubular chamber surrounding an open central area, allowing clear viewing of the weld. The chamber is bounded by two spaced skins and inner and outer walls extending between the skins. An inert gas can be introduced into the chamber under pressure. One skin is generally planar and perforated, allowing the gas to exit the chamber. In use, the chamber is secured to a welding device for movement therewith, with the central opening opposite the weld head and the perforated skin adjacent to the panel being welded. As welding proceeds, an inert gas is fed into the chamber and escapes through the perforations and passes into the central area, preventing entry of ambient air which would contaminate the weld during welding and solidification of the weld.

Abstract: A method and apparatus for soldering a workpiece in a non-oxidizing gas are achieved by comprising conveyors running in a substantially horizontal direction, for holding and moving a workpiece in the horizontal direction, a flux supplying unit for supplying flux to the workpiece, a solder bath including solder and disposed under the conveyors such that the workpiece with a parting portion parting from the top of solder flow is dipped in the top of solder flow, and jetting unit provided at an exit side of the solder bath with respect to the conveyors and connected to a non-oxidizing gas source, for jetting non-oxidizing gas from the non-oxidizing gas source into a region defined by the parting portion of the workpiece and a vicinity thereof.

Abstract: In an automated final weld apparatus, a transporter conveys nuclear fuel-loaded cladding tubes successively to a check station to verify the presence of a plenum spring in the open end of each cladding tube, a reader station where a unique first end plug serial number is read, an evacuation/backfill station where the cladding tube is backfilled with helium, a seam welding station where a final end plug is welded to the cladding tube open end, and a seal weld station where the tube is pressurized with helium through a pressurization hole in the final end plug, whereupon the pressurization hole is welded closed. After checking for helium leakage, the seam weld is inspected in a succession of inspection stations, and, depending on inspection results, the finished nuclear fuel rods are sorted into accepted and rejected lots.

Abstract: An apparatus and method of reflow soldering electronic components, preferably to printed circuit boards, in an inert atmosphere to reduce solder defects and the need for flux or cleaning wherein the inert atmosphere is provided from a source of inert gas through several distribution lines which parallel the conveyor belt of a reflow solder furnace and supply each end of porous sintered metal diffuser tubes situated above the conveyor belt, as well as gas knives situated in baffle compartments at the inlet and outlet of the reflow solder furnace to strip barrier layers of oxygen atmosphere from the electronic components and preclude ingress of oxygen atmosphere into the reflow solder furnace.

Abstract: An improved method and apparatus for shielding inert gas from seeping out of metal pipes in a welding application wherein a high-temperature resistant purge strap is placed around the weld gap and the pipe ends. Advantageously, the purge strap is equipped with a window to allow the welder access to the pipe ends. Dams may be inserted into each pipe near the end to be welded, the purge strap placed about the pipes covering the end of each, and inert gas pumped into the pipes, displacing the air within the pipes. A weld bead is laid into the gap and the purge strap is shifted around the circumference of the pipes to allow completion of the weld. The purge strap device is also disclosed.

Abstract: A cover plate extends over at least part of a solder reservoir and has a slot for a solder wave to extend up above the cover plate. Shield gas is supplied under the cover plate to blanket the solder wave and prevent air from contacting the solder wave and circuit boards passing through the solder wave. Circuit boards are generally supported by conveyor fingers at side edges and the fingers pass through the solder wave. End shrouds are provided at both ends of the solder wave to prevent the entry of air through the conveyor fingers and to ensure that the side edges of the circuit board are uniformly blanketed by shield gas directed to the side edges passing up through the slot in the cover plate. The under surface, front edge, back edge and side edges of a circuit board are therefore uniformly blanketed by shield gas as the board passes through a solder wave.

Abstract: A soldering apparatus is disclosed which includes a longitudinally extending, air-tight housing having four contiguous, first through fourth zones and and inlet and outlet openings at both longitudinal ends thereof, a conveyer for conveying an article to be soldered along a predetermined path extending through the inlet opening, the first to fourth zones and the outlet opening, a soldering device provided in the second zone for applying a molten solder to the article traveling through the second zone, a plurality of upper and lower partition plates disposed in each of the first, third and fourth zones to partition each zone into a plurality of open ended chambers, an inert gas diffuser provided within at least one of the chambers of the third zone, and an air diffuser provided within at least one of the chambers of the fourth zone, so that the diffusion of air from the fourth zone to the third zone is substantially prevented while the diffusion of the inert gas from the third zone to the outlet opening throug