Abstract: An apparatus for repairing high temperature process vessels while at or near their operating temperatures, which may be up to 3000.degree. F. The apparatus includes a lance, a welding apparatus at the distal end of the lance, and power supply and control cabling within the lance. The welding apparatus is contained within a protective housing and both the lance and the housing may be either air- or water-cooled.

Abstract: A system for automatically feeding studs to the electrode of a manual stud welding tool. The system comprises a magazine associated with the tool. The magazine receives a tandem row of studs mounted in and collated by a disposable mounting and collating strip assembly. A drive assembly is associated with the magazine to advance the mounting and collating strip assembly such that each stud, when it becomes the forwardmost stud of the tandem row, is properly positioned with respect to the tool to be welded to a workpiece.

Abstract: A stud holder for a stud-welding device with a through-duct has an outlet orifice and a first holder with resilient holding fingers which extend in the longitudinal direction of the through-duct and each have, in the region of the outlet orifice, holding portions distributed round a periphery of the through-duct. The device further comprises at least one second holder with resilient holding fingers which extend in the longitudinal direction of the through-duct over a proportion of its length, each holding finger having, at one end region, a holding portion which rests on a circumference of the through-duct, the holding portions of the holding fingers of the second holder and optionally of each further holder ending before the holding portions of the holding fingers of the first holder.

Abstract: The device proposed is designed to weld together at least two parts (1, 2) using arc-welding or resistance-welding, in particular pressure arc-welding, techniques. An arc is struck across a gap between the two parts (1 and 2), thus causing them to melt. In oder to ensure a very precisely defined vertical gap between the parts, the second part (2) is first placed on the first. The final position, determined by a program-control unit (12), is measured by means of a travel-measurement instrument (10). Starting from this "zero position", the bolt is lifted through a freely programmable distance and the main welding current activated. On expiry of the prescribed period of time, the bolt on the second part (2) is moved towards the first part (1), this movement also being carried out under program control.

Abstract: To form a welded joint between a fastening means (1) and a structure (2), a fastening means (1) with a holder (3) and a connecting element (4) is proposed. The holder (3) essentially consists of an electrically insulating material. The connecting element (4) consists of a substantially electrically conductive material. The holder (3) substantially surrounds the connecting element (4). The connecting element (4) has a contact face (5) located inside the holder (3). The holder (3) has a through-orifice (6) at least partially overlapping the contact face (5). A contact piece (7) of an electrically operated welding device is introduced through the through-orifice (6).

Abstract: In a welding method for the connection of a component (6) to a workpiece (7) by means of an arc between the component end and a welding point on the workpiece (7), the arc voltage is set and is monitored continuously during the welding process. The component lift is in each case automatically adjusted accordingly.

Abstract: A welding device, in particular a stud welding device with a stroke compensating arrangement comprises a clamping member cooperating with a dragging sleeve and a conically shaped region of an actuating pin capable of reciprocating in its longitudinal direction. The dragging sleeve at least partially surrounds the clamping member and the region. The clamping member is designed in the form of a hollow cylinder with at least one elastic portion which can be brought to rest radially on the dragging sleeve by the region, and a carrier member is provided on which the clamping member rests in part.

Abstract: An electric welding device for welding a fastening element (4) having a through-duct (17) on a workpiece is proposed. The welding device comprises a conveying and holding system (1) having a guide member (2) with a guide duct (3). The fastening element (4) is supplied to the guide duct and is held in one of its ends during the welding process. Within the guide duct there is arranged a loading member (6) which is capable of moving to and fro in the longitudinal direction thereof and has a head (7) which can be brought to rest on the fastening element (4). The loading member has a duct (9) with an inlet (10) and an outlet (11) formed on the head (7). A gas supply duct (12) opens into the guide duct (3). The loading member (6) closes the gas supply duct (12) in a first position. In a second position, the loading member (6) connects the inlet (11) to the gas supply duct (12) so a gas flows to the welding position during the welding process.

Abstract: The invention relates to a process for the application of components strung together in the manner of a belt onto workpieces in which the components are intermittently brought successively into a separating position for a respective component. The component halted in the separating position is initially grasped by a spatially movable jointing tool brought to the separating position over a free path, the jointing tool being held in its position defined by the halted component, the grasped component then severed from the subsequent component and is finally transferred by the jointing tool into the respectively desired jointing position remote from the separating position, in which the component is fastened on the workpiece, for example by electric arc welding.

Abstract: Electric welding device (5) for welding a fastening element (4), in particular a weld stud, on a workpiece with a stud holding means (1) comprising a conveying duct (2) which is connected at one end to a supply duct (3) and holds a fastening element (4) in its other end during the welding process and including a loading pin (6) which is displaceable to and fro along the axis of the longitudinal direction of the conveying duct. The pin has a shank part (13) and a head part (12) which can be brought to bear on a fastening element (4). At least the head part (12) of the loading pin (6) is an electrically insulating surface.

Abstract: An automatic welding stud feeder for a stud welding gun 10 comprises a magazine 40 provided at the upper side of the gun and a transfer lever 26 for transferring the respective foremost welding stud in the magazine 40, by pivotal movement through a substantially quarter-circular path, to an operating position in front of a welding electrode 14. The driving force for the transfer lever 26 is generated by springs 24 which are compressed when the welding electrode 14 with the stud 43 is pushed against the workpiece 50. In its rest position, the transfer lever 26 is locked by a catch 36. The catch 36 is actuated by a release lever 35 which is operated with the thumb of the same hand that holds the welding gun.

Abstract: A stud welding device comprises a receiver and a T-shaped transverse passage through which a T-stud may pass to an axial bore of the receiver and into the path of a plunger which carries the stud into a welding position. A fulcrum is provided in the axial bore about which the T-stud can pivot or rotate to a deflected position that avoids jamming.

Abstract: A retractable feeding rod is located in a guide cylinder. A workpiece retaining pipe is connected to a leading end of the guide cylinder which serves as a movable electrode and a feed-in passage for a workpiece positioned at an acute angle to the guide cylinder. It opens within the guide cylinder and a control surface is provided for appropriately regulating the advancing speed of the workpiece in an end or in the middle of a passage through which the workpiece is fed to the guide cylinder to prevent the guide cylinder from being damaged or worn by the workpiece that impacts the guide cylinder at a high speed.

Abstract: An apparatus for transporting a plurality of fasteners in an automated changing system, i.e., in a robotic tool changing system, wherein the system includes a tooling adaptor assembly adapted to be coupled and decoupled to and from a robot adaptor assembly. The transport apparatus includes a first member which has a first passage formed therethrough and a second member which has a second passage formed therethrough. Both the first and second members are mutually adapted for alignment to one another when the adaptor assemblies are coupled. When the adaptor assemblies are coupled together, the first and second members form an interface fitting so that the plurality of fasteners, i.e., studs, may pass therethrough, and ultimately be transported to a tool, i.e., a stud welding gun.

Abstract: A new adjustable collet for stud welding employs a plurality of electrically energizable jaws coordinated to firmly grasp studs of various shapes, sizes and orientations while welding them to a work surface. This adjustable collet will also ensure better contact with the stud and thus reduce the likelihood of arcing and faulty welds. Premature collet wear will also be averted by reducing the amount of sliding contact between the collet and the stud.

Abstract: A welding head for projection welding wherein the spring which biases the electrode is initially preloaded to exert a significant biasing force on the electrode to maintain it against a stop to define the normal fully extended position of the electrode. The spring of the welding head is also initially precalibrated to exert an accurate predetermined biasing force on the electrode when the electrode is depressed inwardly so as to effect compression of the spring by a predetermined distance, which latter distance is of very small magnitude. The welding head is disposed in engagement with overlapping sheets so that the electrode is engaged with the sheets in alignment with a projection thereon, and the electrode is depressed through said predetermined distance so that a uniform predetermined biasing force is applied to the electrode and hence to the projection weld area.

Abstract: According to the present invention, the inputs of the pilot power supply and the welding arc power supply are connected to a common terminal and there is provided the switching means to selectively switch the operations of the pilot power supply and the welding arc power supply with the switching means switching the power supplies to activate the pilot power supply when a pilot arc should be produced. Thus, the power supply system requires only one secondary winding in the transformer, and the single secondary winding is sufficient to make it possible to use a small and low-priced transformer. This results in reduction in the size as well as the cost of the power supply system. In addition, since the switching means can be composed of the rectifying thyristors connected to the A.C.

Abstract: A welding apparatus comprising a hollowed tubular stud-receiving portion including an axially extending slit at the end thereof and a reduced inner diameter portion at the inner side of the end thereof; and an adapter opened to communicate with the stud-receiving portion for feeding a flanged stud having a shank and a flange formed at an end of the shank into the stud-receiving portion with the flange at the leading end. A collet is positioned to be axially slidable in the stud-receiving portion and provided with a bore at the end thereof to receive the stud shank in the bore, and at least the end portion of the collet is made of an electrically conductive material. Collet driving means is provided for driving the above collet to move the same between a retracted position in which the collet end is placed rearward of the opening of the adapter and a projecting position in which the collet end projects from the end of the stud-receiving portion to apply urging force to the stud.

Abstract: A weld monitoring and evaluating circuit (10) for non-destructively determining if a just-completed weld is a satisfactory or an unsatisfactory weld. The circuit is used to derive the temperature at the weld zone in real time by determining the total power input to the weld zone, taking into account losses experienced at the weld zone, and dividing the result by the thermal mass of the weld zone. The predicted temperature at the weld zone is compared against an electrical signal representing at least a minimum desired welding temperature needed to be attained at the weld zone to produce a satisfactory weld at the time that the stud (16) contacts the weld pool (18a) (e.g., the "plunge event"). If the derived weld temperature signal has exceeded the reference signal at the time the plunge event occurs, then it is assumed that a satisfactory weld has occurred.

Abstract: The invention relates to a welding process for drawn arc stud welding wherein after ignition of the main current electric arc, the latter's voltage (U) is measured and, depending upon the measured voltage, the current flow of the continued main current electric arc and/or the dipping movement of the parts which are to be welded together, is regulated or controlled.

Abstract: Disclosed is a stud for a boiler or other high temperature application, such as a furnace. The stud is made of an iron aluminum alloy which comprises about 81 to 91 wt. % iron, about 8 to 13 wt. % aluminum, about 0.01 to 0.3 wt. % carbon, and zero to about 3 wt. % of a refractory metal and/or zero to about 1.5 wt. % zirconium. The studs are welded to a surface of a component of the boiler or furnace by arc or resistance welding. The aluminum of the iron aluminum alloy imparts good oxidation and sulfidation resistance to the studs. The alloy also has a good electrical resistance which makes the alloy especially useful for arc or resistance welding. The aluminum content acts as a getter to eliminate gas porosity in the resulting welds. The present invention is particularly useful for making boiler heat exchange surfaces or refractory covered surfaces wherein the studs function as refractory anchors.

Abstract: The connection of structural component parts in adjusting devices for seats, in particular for motor vehicle seats, is disclosed. In connecting structural component parts for adjusting devices for seats, the structural component parts to be rigidly connected with one another are welded in their connecting region. In order to prevent distortion of these structural component parts caused by the welding process, one structural component part has at least one bevel which projects toward the connection side and can be pressed into at least one recess of the other structural component part during a capacitor impulse welding process, this recess substantially conforming to the bevel with respect to shape and dimensions.

Abstract: A capacitive stud welding having an inductive-capacitive welding current supply circuit is provided with a stud and a tunable inductor. The stud is attachable to a workpiece and has an end portion shaped to retain in place on the workpiece at the weld point the flux from the stud to form an optimum weld. The tunable electrical inductor optimizes resonance of the inductive-capacitive welding current supply circuit and the flow of welding current through the stud and workpiece.

Abstract: A battery powered dent puller for re-contouring sheet metal having a dent is disclosed. A direct current welding electrode mounted on a handle allows the user to attach the electrode to an indentation in sheet metal with a very brief surge of 12 volt direct current. The welding current is regulated by means of a switch mounted on the handle which controls a relay through which the current travels. Once the electrode is attached on the sheet metal, the user may pull with considerable force in a direction that is generally in-line with the electrode. The force of the user pulling on the sheet metal tends to alter the contour of the metal, thus pulling out the indentation. To disengage the electrode from the sheet metal, the user twists the electrode, which breaks the weld. The battery power supply allows portability, increases safety, and tends to reduce assembly costs.

Abstract: A stud welder which includes a welding head having a stud receiving and retaining mechanism for holding an end of a stud towards a workpiece, a linear actuator having a fixed permanent magnet, a movable coil coupled to an acutator shaft and the actuator shaft coupled to the welding head and a controller coupled to the actuator coil and to the welding head and operative to move the actuator coil and welding head from a retracted to an extended position and back again and to cause welding current to flow into the welding head.

Abstract: A welding stud designed to have reduced weight without loss of strength by having a stepped diameter, cylindrical form shank with a relatively thin head. The head is centrally depressed and the shank is of a first relatively large diameter closely adjacent the head and is extruded to a smaller diameter from there to the end opposite the head. The weight is additionally reduced by providing the head with a central depression which extends into the head from the axial outer end. The method of forming the stud starts with a workpiece of a diameter larger than the final desired stud diameter and cold heading the workpiece to form the stud head. Thereafter, the shank of the workpiece from a point spaced from the head to the free end of the shank is extruded through a circular die to reduce its diameter to the desired final diameter throughout the majority of its length.

Abstract: Welding studs are punched from a metal band in such a way that a shank 11 of the stud is formed from a metal strip which is integral with a head 10, partly cut free therefrom and bent at right angles with respect to the plane of the head 10. For sufficient bending resistance, the metal strip forming the shank 11 is bent about the shank axis, preferably to such an extent that both lateral edges 15, 16 of the strip contact each other.

Abstract: A stud which is automatically fed so as to welded stably and properly, has a large electric contact surface with the collet, facilitates clip attachment, and maintains the engagement firmly after the attachment of the clip. A stud 1 extends upwardly into a rod-like form which is threaded on its periphery, and includes a welding tip at the lower end thereof for welding to a base member such as a panel so as to be used in mounting a member to be attached on the base member. The stud 1 is formed to be short in overall length and its welding tip is formed as a flange 4 whose diameter is larger than that of the rod-like body. A crest 6 of the screw 3 is formed flat. An upper flank angle 8 of the screw is formed large while a lower flank angle 10 of it is formed small. An edge 12 of an upper end 11 of the stud is chamfered.

Abstract: An electric stud gun positioning apparatus is attachable to a collar of a stud gun and has making parts for aligning and orienting the stud relative to a part on which the stud is to be welded.

Abstract: An apparatus for welding a stud to a substrate has a housing, a rear tubular element fixed in the housing and defining a rear passage portion, and a front tubular element in the housing defining a front passage portion itself defining an axis and forming with the rear passage portion a continuous passage. The front tubular element has a front end and is limitedly axially displaceable in the housing between a front position and a rear position. A spring braced between the front tubular element and the housing urges the front element axially forward relative to the housing into the front position. A chuck or holder at the front end is adapted to hold the stud. A sleeve fixed to the housing has a front edge lying axially rearward of the front end in the front position of the front element and axially forward of the front element in the rear position so that when the stud in the holder is pressed axially forward against the substrate the stud and front element move axially backward in the housing.

Abstract: A system (10) and method for predicting weld quality in a stud welding system by measuring the displacement of a movable shaft (20) with respect to the gun body (12) during the weld process. A sensor (34) is positioned with respect to the welding system in order to produce a series of discrete signal values each indicative of this displacement. These values are plotted graphically and used to produce a weld "signature" which can be compared with signatures of welds of known quality to more accurately predict the quality of the current weld. Based on these weld signatures, various weld parameters including current, time and lift can then be adjusted until a consistent signature indicative of good weld quality is produced.

Abstract: A stud welding apparatus has a welding jig, guide frames and a cartesian coordinate type robot. This robot has a travelling frame, a robot main body, an elevating arm and a stud welding gun. Power supply passages are provided on the travelling frame, the robot main body and the elevating arm, respectively, such that electric power can be supplied from a welding power source to the stud welding gun via these power supply passages. The power supply passage provided on the travelling frame is formed in a first power supply bar which is fixed to the travelling frame and is elongated in a horizontal direction. A pressure type first power supply joint is provided on the robot main body and urges a contact member to be connected to the power supply passage provided on the robot main body into contact and away from the first power supply bar by means of a cylinder.

Abstract: In order to be able to weld on studs (2) with a larger than normal diameter, a stud-welding process is proposed in which the pressure applied to the stud (2) before the welding current is triggered is applied symmetrically to the stud axis (A), but extra-axially and adjustable as appropriate, thus ensuring better centering during the welding operation and also improving the quality of the weld. A suitable pressure-application device (27) is proposed for this purpose.

Abstract: A stud welding gun 1 has a collet 4 to hold a stud, a piston to push a stud out to the collet, and a feed pipe to automatically feed studs one by one. A stud receiving member 15 to receive and store studs is provided between the collet and the stud feed pipe and the stud receiving member is provided with at least two stud receivers 16. Each stud receiver is capable of moving between a first position in which it receives a stud and a second position which continues to the collet and in which a stud pushed out by the piston is held by the collet, and when a stud receiver 16 is in the second position, another stud receiver is in the first position. By this, the receiving of a stud is carried out simultaneously with the loading of a stud to reduce the working time.

Abstract: An arc shield is used in projection welding. The projection welding is performed for welding the lower end of a metal stud to the upper surface of a metal plate. The stud has a head and a stem connected securely to the central portion of the lower surface of the head. The arc shield includes an annular horizontal top wall defining a hole therein, and an annular vertical side wall having an annular top end connected securely to the outer peripheral portion of the top wall, and an annular bottom end having a plurality of notches. The annular side wall defines a chamber therein. The hole of the top wall has a size slightly greater than the diameter of the stem of the stud so as to allow for extension of the stem of the stud into the chamber through the hole of the top wall. When the projection welding is being performed, the electric arc is enclosed within the arc shield, while the surplus gas and molten metal that occur in the chamber flow from the arc shield through the notches of the annular side wall.

Abstract: Apparatus is presented herein for controlling a stud welding gun for welding a stud to a workpiece. The stud welding gun has a gun body and a gun shaft mounted to the body in such a manner to permit reciprocal movement of the shaft relative to the body. The shaft has a distal end having means for carrying a stud to be welded to the workpiece. A linear motor is carried by the gun for directly driving the shaft in forward and reverse directions between fully extended and fully retracted positions relative to the gun body. A floating point detector provides a control signal when the stud engages the workpiece as the shaft is being driven in a forward direction to establish a reference position of the gun body relative to the workpiece.

Abstract: The invention keeps welding time constant by appropriately setting the time of stud descent determined by the de-energization of lift means so as to obtain stable quality of welding. A stud welding machine has a welding gun having a collet to hold a stud and a lift coil to lift the stud from a base material. A control device is connected to a power source and the welding gun and functions to supply power from the power source to the welding gun to produce a pilot arc and later a main arc. The control device energizes the lift coil to lift the stud to a predetermined height to produce the pilot arc and the main arc, and it de-energizes the lift coil so as to bring the stud into press-contact with the base material to make the weld. The control device has a voltage detector to detect that the stud is in press-contact with the base material and to stop the power supply from the power source to the welding gun upon receipt of a press-contact signal from the detector.

Abstract: Method and apparatus for automatically compensating for spring fatigue and aging, mechanical wear, and the like in a stud welding machine. In order to hold plunge time at an ideal constant value, the plunge times of each weld are measured and a running average is generated to adjust the command to drop the stud onto the workpiece as necessary to hold plunge time substantially at the ideal constant value.

Abstract: A stud welding device for use in welding T studs comprises a receiver into which T studs are fed from a feeding device and located in the path of a plunger which carries the stud into a welding position. Spring means are provided in the receiver to engage the head of a T stud fed into the receiver to hold the stud in place thus to reduce the possibility of jamming.

Abstract: A stud welding device comprises a stud holder and a movable member which moves the stud holder to carry a stud into position for welding. The movable member is provided by the stator or the armature of a helical thread reluctance motor.

Abstract: Apparatus is presented herein for controlling a stud welding gun for welding a stud to a workpiece. The stud welding gun has a gun body and a gun shaft mounted to the body in such a manner to permit reciprocal movement of the shaft relative to the body. The shaft has a distal end having means for carrying a stud to be welded to the workpiece. A linear motor is carried by the gun for directly driving the shaft in forward and reverse directions between fully extended and fully retracted positions relative to the gun body. A floating point detector provides a control signal when the stud engages the workpiece as the shaft is being driven in a forward direction to establish a reference position of the gun body relative to the workpiece.

Abstract: Parts are fed at an optimum speed to a device installed at the end of a feed passage. The invention is characterized in that the basic arrangement comprises a device for once stopping a part, the device being disposed at a position separated a required distance from the parts holding device, and in that a movable shield member is installed at the side to which parts and the feed rod are advanced. Further, the arrangement is applicable to a stud welding apparatus.

Abstract: Process for welding a weld stud onto a workpiece by means of a drawn arc, in which the weld stud is placed onto the workpiece and, with performance of a welding stroke, is removed from the workpiece in a return stroke, igniting a pilot arc, and is advanced toward the workpiece again in a forward stroke during the combustion of a connected welding arc. The welding arc is divided by pulse-wise current reduction to a minimum value into a sequence of current pulses and the last of these current pulses is extended in time by at least about 1.5 times relative to the preceding current pulses. This extended current pulse lasts substantially to the end of the forward stroke.

Abstract: A stud welding machine features several welding outputs for welding tools with different polarity for various welding operations. The polarity of at least one welding output is reversible.

Abstract: Method and front-end fixture adapted for use with manually-operated electric stud welding guns, which permits the successful welding of a plurality of metal studs uniformly onto a workpiece. Various aspects of the invention provide for repeated accurate spacing of the studs as they are successively welded, for accurate alignment of a series of studs, and for each stud to be oriented in a disposition substantially perpendicular to the surface of the work piece. The preferred embodiments include a bracket mounted to a conventional welding gun, an alignment bushing mounted on the bracket forward of the chuck of the gun for contacting a previously-welded stud, and a footpiece mounted on the bracket rearward of the chuck.

Abstract: A welding apparatus welds shear studs onto a horizontal surface and uses ferrules as weld molds. The apparatus includes a weld module having a frame and having a welding gun with a chuck, the module being translatably mounted to a carriage, a holder mounted on the frame which holds a stud in a first position and a ferrule in a second position, and a driver which drives the weld module downward so that the chuck contacts the stud and drives a lower portion of the stud into the ferrule.

Abstract: An attaching assembly is disclosed which permits attachment of ceramic fiber to a back plate. The assembly includes a stud retainer plate having a perforation, such as at the center of the plate. The stud retainer plate can be affixed to a perforate backing element, e.g., a metal mesh. On the side of the stud retainer plate opposite the backing element, there is a tube retainer. This tube retainer is secured to the stud retainer plate. An elongated, removable tube can be inserted into the tube retainer. A stud can be inserted through the removal tube, and through the retainer plate perforation and perforate backing element. The stud is then welded to a back plate, e.g., a solid furnace wall. A refractory element inserted in the retainer plate perforation insulates the stud from the retainer plate to prevent arcing during welding.

Abstract: A stud welding system which utilizes a stud welding gun capable of interacting with the stud welding power supply and welding controller in a manner such that the extent and rate of lift, duration of holding and lift position and extent and rate of plunge can be independently varied and controlled over a wide range. The interactive stud welding gun utilizes a stepping motor in the stud welding gun which actuates the gun shaft assembly and its associated chuck carrying the stud to be welded. A transducer associated with the stud welding gun senses the position of the gun shaft assembly relative to the gun body and provides a reference signal therefor. A microprocessor controlled interactive gun control responds to the signal from the tranducer to determine gun shaft assembly position and generates an energization signal for the stepping motor to drive the gun shaft between lift, hold and plunge positions preprogrammed into the interactive gun control.

Abstract: The next stud is blown under pressure into the receiver after a stud has been welded and as the rod which locates the stud for welding is withdrawn to its fully retracted position the next stud is first subjected to a vacuum which draws the next stud into the collet and then blown fully into the collet.

Abstract: An arc stud welding machine having an arc shield mount section for retaining a generally semicylindrical arc shield segment. The arc shield mount section has a semicylindrical inner clamp member for abutment against an inner surface of said arc shield segment, two quarter cylinder outer clamp members for abutment against an outer surface of said arc shield segment, and pressure screws for applying pressure in the direction of said arc shield segment to said outer clamp members at approximately the middle of the periphery thereof.