Abstract: This electric stud-welding device includes a welding gun for a stud or bolt to be welding to a workpiece, and a control device. The latter consists of a welding current source and a setting device for welding time and welding current. The welding gun and the control device are connected through two welding current lines. A pilot current circuit is present, using only the two welding current lines (5, 6). Also present is a setting device (10), coordinated with the welding gun (3), which is switched into the pilot current circuit. In the control device (2), there is a sensor (9) which, dependent on the control signals produced by the setting device (10) each time, after the actuation of the selective switches or setters (13, 14) arranged thereon, controls the control device (8), present in the control instrument, for the welding time and the welding current.

Abstract: Apparatus is provided for welding a stud to a workpiece. The stud is positioned against the workpiece in such a manner that the stud retracts from an extended first position to a second position against the workpiece. The stud is then retracted away from the workpiece to a fully retracted third position. Welding current is provided so as to establish a welding arc between the stud and the workpiece as the stud is being retracted to the third position. The stud is then plunged toward the workpiece to make contact therewith. The displacement of the stud from its initial first position to the second position is measured during the time that the stud is in engagement with the workpiece and before the stud is retracted therefrom to the third position. The plunging of the stud toward the workpiece is controlled as a function of the measured displacement in such a manner as to control the point in time at which the stud makes contact with the workpiece.

Abstract: A stud welding system wherein welding is prevented unless the armature is located within an acceptable displacement window. A D.C. signal representative of armature position is generated by connecting differential amplifier across the coil and applying a constant voltage across the coil. The output of the amplifier is converted to a D.C. signal which is received by window comparator which will enable welding only when the armature is properly located.

Abstract: Stud welding apparatus comprising a housing, a spring-loaded stud holder which holds a welding stud in welding position by its resilient restoring force, a feed channel through which the stud is delivered into a substantially cylindrical space within the stud holder, and loading means which is movable relatively to the welding stud by a pneumatic piston and which presses the stud into the stud holder against the resilient restoring force, characterized in that the loading means is pivotally attached about an axis fixed in relation to the housing, that at least one lever is disposed between the loading means and the pneumatic piston whereby the pivotal point of said lever on the loading means is spaced by a small distance from its axis of rotation and that loading means, lever and the movement of the pneumatic piston are coordinated so that loading means is pivotable between a loading position, in which the feed channel is cleared, and a position in which the loading means presses stud into the stud holder.

Abstract: Apparatus and a method of using it to straighten a dent in a sheet metal workpiece are provided. The apparatus includes a stud welding gun to releasably grip a stud and weld it to the dent, as well as integral hammer means to apply force to the welded stud, straightening the dent. The apparatus and the method of use then provide means for dewelding the stud from the straightened workpiece, thereby avoiding the usual stud cutting and grinding operations. Exchangeable electrodes are provided so that the apparatus can be used for both stud welding and spot welding.

Abstract: A connection arrangement with profiled parts contains, in at least one hollow chamber in a profiled part, a connecting element by means of which a connection with the other profile part is effected. The purpose of the invention is to provide, at low manufacturing cost, a reliable connection and to eliminate any after-treatment of surfaces in the vicinity of the connection. It is proposed that the connecting element be secured to the web of the first profiled part and that a length thereof projects, prior to welding, beyond the front surface; and that, after welding, the weld-zone be arranged in the hollow-chamber in the second profiled part and be at a distance from the adjacent front surfaces of the profiled parts.

Abstract: A welding apparatus for welding a new stud on to the end of a broken-off stud which comprises a conventional mig welding hose through which inert gas can pass and through which a mig welding wire can be fed, the hose having a conventional extension at one end thereof for attachment of a mig welding nozzle thereto, the extension also having a longitudinally extending contact tip guide attached thereto and through which the welding wire passes, the nozzle having an enlarged cylindrical portion which is received over the extension of the hose, and a reduced cylindrical portion extending over and beyond the contact tip guide in concentric relation thereto. The mig welding hose has a trigger for initiating the flow of inert gas through the hose and into the annular area between the guide and the nozzle, for supplying a d.c. welding voltage and for feeding the wire through the hose and through the contact tip guide.

Abstract: A welding system for welding a new stud onto the end of a broken-off stud which comprises a welding gun having a forward end and a rear end, the forward end of the gun supporting a new stud to be welded to the end of a broken-off stud, the new stud being threaded at least along a rear portion thereof, a shroud mounted at the forward end of the gun and surrounding the new stud, the forward end of the new stud projecting outwardly from the gun into the shroud, the new stud having a longitudinal bore extending from the rear end thereof to a location adjacent to the forward end thereof where the bore flares outwardly to a larger bore at the forward end of the new stud, the new stud also being provided with slots at the forward end diametrically opposite from each other and in the region of the enlarged bore, a coated welding rod supported by the gun and extending from a location adjacent the rear of the gun through the bore in the new stud and to a point adjacent the forward end of the new stud, the welding rod h

Abstract: A resistance weld pin for securing insulation to duct interiors is disclosed. A characterizing feature resides in the provision of a layer of heat activated adhesive on the under surface of the washer of the weld pin, which adhesive is melted in the course of forming a resistance weld and bonds to the surface of the insulation, defining an annular air seal surrounding the pin.

Abstract: A resistance welding pin for connecting insulation batts to ducts comprises a head having a shank and a sharpened tip remote from the head. The shank, adjacent the tip, includes an abutment against which a welding electrode may bear, the electrode being passed through an aperture or passage in the head.

Abstract: A multi-operator grid system for stud welding is disclosed which works in conjunction with a microprocessor controlled single stud welding power supply. The multi-operator grid system utilizes a single multiplexer interconnected with a plurality of weld stations each of which includes an isolator, hand held terminal and stud welding gun. Each hand held terminal working through the multiplexer can program the microprocessor stud welding supply for parameters of pilot arc and welding current energy and cycles. The microprocessor controlled stud welding supply, through the multiplexer, provides read outs to printers and to the hand held terminals of the resultant stud welding parameters such as total welding energy, weld current and the like. The multiplexer, working in conjuction with the microprocessor controlled stud welding supply and the isolators, controls the pilot arc and weld current to the stud welding guns as well as the plunge thereof.

Abstract: A method and apparatus are provided for welding a stud to a workpiece and maintaining the area around the weld substantially free of smut. The existence of the smut detracts from the appearance of the workpiece and, if the workpiece is to be painted or otherwise covered with a coating material, the smut must first be removed. A spark shield assembly has an outer end which is placed in contact with the workpiece around the stud. Anti-smut liquid is first deposited from the assembly on the weld area around the end of the stud where the weld occurs thereby to eliminate the deposit of a coating of smut. Air is then directed through the spark shield assembly toward the outer end thereof after the weld is completed to aid in removing the anti-smut liquid from the spark shield assembly.

Abstract: Control circuit for arc welding components to workpieces, in which a component is placed on to a workpiece by a weld gun and after a welding stroke is lifted from the workpiece in a return stroke by igniting a pre-current arc and is brought up to the workpiece again in a forward stroke during the burning of an interconnected welding arc, in which a sequencing control determines the tripping moments of return stroke and forward stroke as well as of the welding arc and a monitoring voltage is bypassed from the pre-current arc ignited at the welding point, characterized in that the monitoring voltage (V) is converted into a correction voltage (line 27) by means of a set-point comparator (25) and is superposed on a control voltage (line 18) for principally controlling a high-frequency modulated switching mode power supply unit (15) and said switching mode power supply unit (15), in accordance with the thus corrected control voltage, adjusts its output current (lines 13,14) during the respective welding operation

Abstract: A connector assembly for a stud welding device is provided. The connector assembly facilitates removal of jammed studs and prevents studs from shooting out of the feed tube when the assembly is removed.

Abstract: An electric resistance welding apparatus is shown for attaching insulation to duct work comprising a supporting anvil with a surface for supporting a sheet metal duct work with a covering sheet of insulating material and a movable hammer member spaced from and movable relative to the anvil. The hammer member has one or more magnets for supporting a resistance welding pin and is movable to drive the pin through the insulating material to engage the sheet metal duct work. The hammer member and anvil are connected in an electric welding circuit to supply current from the hammer through the pin to the anvil to fuse the end of the pin to the sheet metal with the head of the pin holding a washer tightly against the insulating material. The hammer member and anvil are both copper with recesses having cylindrical copper electrode members removably positioned therein. In one embodiment, the hammer member recess is deeper than the copper electrode member, and the magnet fits the recess behind the electrode member.

Abstract: The invention relates to a method of securing a first part made of a thermoplastic material to a second part made of an electrically conductive material, a connector means of an electrically conductive material being placed in the part made of a thermoplastic material and subsequently being welded to the part made of an electrically conductive material. A metal ball is used for the connector, which ball is inserted into an opening in the first part and is brought into contact with the second part, after which the ball is welded to the second part by means of a welding electrode.

Abstract: Apparatus and method are provided for sensing the presence of arc discharge in arc welding such that the change in electric current is sensed at the time of discharge and light emitted from a welding position is sensed only when the sensed electric current surpasses a predetermined level.

Abstract: The stud holder has in the interior of the supply passage of the stud holder proximal to the workpiece side of the clamp jaws, a circular groove for engaging and holding a headlike enlargement of the stud in a plane perpendicular to the axis of the clamp jaws. The supply passage is constricted conically, narrowing in the feed direction of the stud, upstream of the circular groove with respect to feed of studs at least adjacent the clamp jaws. The jaws are expandable against a spring tensioned under influence of the stud as the stud is fed.

Abstract: A stud-welding apparatus in which the chuck is axially displaceable to bring the stud into engagement with a detent past which the stud has been propelled so that the stud is held as retraction of the chuck sets the stud in the mouth thereof. The chuck is then advanced to carry the stud away from the detent and into engagement with a workpiece so that the welding current does not affect the detent and mechanical stress is not applied thereto during the welding operation.

Abstract: A stud welding gun has a forepart which includes the delivery end of an automatic stud-feeder and is secured to the housing by a quick releasable joint so as to be readily replaceable by another forepart supplying a stud of different size. The gun includes a pneumatic piston and piston rod which serves to push a stud into the collet after delivery to the gun. The piston rod is detachable from the piston and means is provided for locking it in the forepart so that it is replaced into the forepart for studs of different size.

Abstract: A solenoid power control circuit provides full power during lifting and reduced power during maintaining a lift condition in a lifting solenoid of an electric arc stud welding gun. During the stud lifting portion of a stud welding process, relatively high power is provided to the lifting solenoid to effect work necessary to accomplish the lift; but after a lifted condition has been achieved, the invention phases back power to reduce the energy dissipated while the stud and the lifting solenoid are maintained in lifted condition. A relaxation oscillator having two different charging time constants that can be selected to provide long or short phase delay is employed for the phase modulation control of lifting solenoid energization.

Abstract: A weld attachment device and method are disclosed for effecting resistance welding connections through an insulating layer to a metallic substrate without necessarily having access to the rear surface of the substrate. The apparatus comprises a spaced parallel pair of weld pins supported on an electrical insulating carrier, the device being attached by advancing the tips of the pins into contact with a metal substrate and passing welding current through a circuit defined by the metal pins and the area of the substrate between the pins.

Abstract: Apparatus for welding studs utilizing a two-wire control is provided. The apparatus includes a stud welding tool capable of welding studs by a drawn-arc technique. A stud welding control circuit and a source of welding power are remotely located from the tool with the difference exceeding one hundred feet in some applications. Heretofore, two wires were required to connect the tool and the control circuit to initiate the welding cycle and two additional wires were required to control movement of the stud during the welding cycle independently of the position of a start switch on the tool after the switch is closed. The present apparatus requires only two wires to both initiate and control the weld cycle. This reduces costs and maintenance and increases reliability and maneuverability of the tool.

Abstract: A method and apparatus is provided for attaching forging handles in the nature of studs to metal billets. The billets are passed in end-to-end relationship through a furnace following which the heated billets are individually delivered to a welding station where a welder welds a stud to the billet. The welder includes a welding head which is shifted by a translation mechanism from a feeding position where studs are successively fed to the welder to a welding position in which the stud is brought into engagement with the billet and electrical current is delivered through the stud to produce the weld.

Abstract: An apparatus for welding studs to a workpiece includes a stud supporting and positioning unit adapted for cooperation with a guide template to provide for accurate positioning of a stud to be welded. The unit includes a centrally located electrode provided with a stud positioning bore and a detent for releasably supporting a stud within such bore; a casing or housing supported on and electrically insulated from the electrode; and a plurality of stud guide pins, which are arranged parallel to the stud positioning bore and supported for axially directed reciprocating movements under the control of spring devices between an extended, guide position and a retracted, stud welding position. The pins cooperate with guide holes provided in the template to accurately locate the stud to be welded. The method involves the mode of forming the template and cooperation of the positioning unit therewith to achieve accurate positioning of a stud.

Abstract: A stud welding tool has an improved plunge dampener and an improved lifting mechanism assembly. The plunge dampener is mounted in a front cover of the tool for easy assembly and disassembly. A threaded member controls movement of the dampener to adjust the amount of free travel of a stud and chuck assembly during a plunge stroke in a welding cycle. The lifting mechanism is mounted in a housing as an assembly. The housing is located in a bore or recess in the welding tool body and held in place by a main plunge spring in the tool. The housing and lift mechanism is easily installed and removed for replacement or repair.

Abstract: An industrial stud welding machine is provided with a chuck which defines a work piece receiving orifice of infinitely variable diameter. The stud welding chuck is thereby able to accommodate studs of different diameters, and is also adjustable to compensate for wear resulting from extended use. The stud welding chuck employs a barrel having an annular wall in which longitudinal slots are defined. The barrel is tapered and threaded externally. A collet encircles the barrel and is treadably engaged therewith. Advancement of the collet in one longitudinal direction squeezes the edges of the barrel walls together to reduce the work piece receiving orifice diameter. Advancement of the collet in the opposite direction along the barrel allows the work piece receiving orifice to open to a larger diameter.

Abstract: This invention relates to the protection of metallic surfaces susceptible to abrasion by rock-like material. According to the invention, a metallic surface susceptible to abrasion by rock-like material is protected by stud welding studs of abrasion resistant metallic material to the metallic surface in closely spaced relationship to cause the majority of the rock-like material to contact the abrasion resistant studs instead of the metallic surface. Typical of such metallic surfaces are a ground engaging tool, earth-working equipment, or chutes for conveying the rock-like material. The abrasion resistant metallic material comprising the stud can be formed of cast material of compacted metallic powder.

Abstract: A large diameter stud and a method and apparatus for welding same are provided. The large diameter stud has a protruding tip at a weldable end thereof containing a solid rod-like body of flux. A ceramic ferrule which can have a two-step cavity surrounds the weldable end portion of the stud when engaged with workpiece to which it is to be welded. An arc blow coil surrounds the ferrule and is spaced therefrom with powdered flux therebetween and above the ferrule. The arc blow coil is attached to adjustable legs of a welding tool and has a weight thereon to aid in supporting the welding tool upright on the workpiece during the welding operation. In the welding cycle, a relatively low weld current is used for the main welding arc and is maintained for an extended period of time. Current through the arc blow coil is initiated when the welding cycle begins and is gradually increased to a maximum at an intermediate point in the welding cycle.

Abstract: A transfer member is provided for welding apparatus wherein fluid is deposited about the weld area during the welding process and T-studs are automatically fed from a remote source to a welding gun. The transfer member comprises two tubular members, one disposed within the other, and sealed one from the other. Studs are transferred through the inner tubular members and fluid, in the form of gas or liquid, is transferred through the outer tubular member.

Abstract: An arc welding device for welding tie elements to a work piece includes a welding head for positioning one tie with respect to the welding spot on the work piece and exerting pressure between the tie and the work piece. A control member determines the amount of energy to be dispensed by the energy source to the welding head. A memory stores data indicating the relation between amount of energy dispensed and various welding parameters. A measuring member supplies values for some of the parameters. A measuring member compares the amount of energy actually dispensed with the energy determined by the memory member and readjusts the setting for the energy source as a result of this comparison.

Abstract: An improved resistance weld pin is disclosed, the pin being especially adapted to hold insulation batts to the surfaces of ducts. The pin is characterized by the provision of axially directed heat radiating ribs which terminate at and extend radially beyond the junction of the tip of the pin and the shank.

Abstract: An underwater arc stud welding system consists of a specially designed submersible stud welding gun which is connected, by means of an electrical umbilical to conventional stud welding equipment located out of the water. The stud gun employs a simple, corrosion resistant, stud lifting mechanism with only one moving part, which freely floods with water and thereby eliminates problems associated with increased ambient pressure and also employs a magnetic base and a grounded electrical safety shield.

Abstract: Improvements to stud welding equipment having automatic stud feeding apparatus. The stud receiving chamber and receiving chamber entrance are positioned for top loading of the studs being fed through a stud loading tube. The stud loading tube and attached stud feed tube are detachably connected to the stud welding gun by a stud block and disconnect assembly which includes a transversely movable slider which provides the dual function of providing the detachable interlock with the stud welding gun and blockage of the stud loading tube when the assembly is detached.

Abstract: A stud welder is provided with a pair of magnetic coils and a compression spring. One of the coils provides the lift to separate electrode held parts and start an arc therebetween. The other coil and the compression spring provide fast follow-up force driving the parts into reengagement to quench the arc and weld the parts together. The combined acceleration of the spring and the booster coil enables the welding of certain materials such as brass which were previously not weldable with stud welders.

Abstract: Stick and stud welding apparatus which utilizes a microprocessor and related RAMs, ROMs and peripheral interface devices to control the welding parameters. The ideal desired weld current and weld cycles in the case of stud welding can be selected depending upon the mode of operation and/or stud conditions. The program for the microprocessor instructs the microprocessor to periodically compare the actual welding current to the ideal current, compute the difference and alter the phase firing time of an SCR bridge to compensate or adjust the welding current to the ideal current. In the case of stud welding mode, the program further instructs the microprocessor to reference the selected number of cycles, compute the total energy delivered across the stud and workpiece gap from actual current, welding terminal voltage and time and enlarge the number of actual weld cycles to a given percentage of that initially selected to provide a total energy input to the stud as selected.

Abstract: The present invention relates to an arc-welding device for securing studs on metallic elements underwater, and comprising a head containing a chamber and of which the welding bead is obtained by means of a dielectric refractory ring placed around the base of the stud, wherein an annular space is provided between the stud and the ring and neutral gas is blown into the chamber through said space, to drive the water out of the chamber and keep up therein a gaseous atmosphere to facilitate the welding of the studs; the refractory ring is produced from borosilicate glass, rich in silica.

Abstract: The present invention provides a capacitor charging circuit for a discharge type welding tool. The circuit includes a rectifier for producing rectified pulsating currents, a capacitor to be charged, a thyristor between the rectifier and the capacitor. A pulse generator receives the pulsating currents and in turn produces a pulse at each hill of the pulsating current. The thus produced pulse is applied to the gate of the thyristor which turns the thyristor on. A charge potential detecting circuit directly measures the charge potential across the charged capacitor and transfers a signal change, according to the level of the capacitor potential, to the pulse generator so as to thereby control the timing of the pulse generation at each hill of the pulsating current.

Abstract: Apparatus is provided for welding studs to a workpiece with the area around the welds being substantially free of smut. The existence of the smut detracts from the appearance of the workpiece and if the workpiece is to be painted or otherwise covered with a coating material, the smut must first be removed. The coating of smut can be eliminated if, during the weld process, fluid is carefully deposited on the weld area around the end of the stud where the weld occurs. The fluid consists of a small volume of low-pressure air and an anti-smut liquid. The latter also helps to keep weld splatter from adhering to the interior of a spark shield used with the stud. However, by applying a non-metallic, preferably plastic, sleeve within the spark shield, the problem of splatter can be further reduced or substantially eliminated.

Abstract: Electrical stud-welding apparatus of greater efficiency and reliability and more simply operated than known stud-welding apparatus. A base member is provided with a tubular housing, an insulating bushing therewithin and a welding piston inwardly of but of greater length than the bushing. Mounted in the housing is an actuating member under the control of a coil compression spring comprising a rod capped on its forward end on the workpiece side of the apparatus. Means including an electrical control circuit actuate the longitudinally moving parts.

Abstract: Method and apparatus for simultaneously welding by the stud end welding technique a stud having two or more ends. The stud includes at least one elongated relatively thin metallic projection from each end of the stud to be welded. The method and apparatus maintains a current density in a given projection sufficient to disintegrate the projection with consequent arc initiation. The resultant arcs melt all stud ends and plate. The molten ends are lowered into the pools at a controlled rate at which time the current is extinguished and the material solidifies.

Abstract: The present invention is directed to an apparatus for attaching welding pins to sheet metal, and particularly for attaching by a resistance welding procedure pins for retaining insulating material to a duct substrate. A characterizing feature of the invention resides in the provision of a fixed hopper member for receiving bulk quantities of weld pins and a carriage movable relative to the hopper for enabling the pins to be applied to the duct at spaced points, the combination including means for discharging a plurality of oriented pins from the bulk supply hopper to the movable carriage responsive to predetermined movement of the carriage.

Abstract: Stud welding apparatus having a clamping sleeve at one end of the apparatus, a delivery tube or passage coaxially of the sleeve, an inlet for a succession of studs in communication with a stud feed and a displaceable setting or holding member for forcing a stud in the stud delivery passage into the stud clamping sleeve, and the setting member having a displacement at least as long as a stud. The succession of studs is fed in such manner that even prior to the termination of the welding process of one stud held in the clamping sleeve the following stud is properly positioned in the stud delivery passage and is introduced into the stud clamping sleeve when the latter is in its return position.

Abstract: The present invention is directed to an improved resistance welding pin especially adapted for fastening of batts of insulating material to metallic air conduits, such as the ducts of air conditioning and heating systems. The pin is characterized by a novel corrugated shank portion extending between the head of the pin and the sharpened tip which functions, inter alia, to dissipate the heat generated in the shank during welding, with a plurality of attendant advantages.

Abstract: Apparatus and methods for replacing or repairing missing or damaged abrasion resistant wearbars utilized in high velocity cyclone boilers. A retrofit wearbar having an aperture therein is utilized in conjunction with an end weldable stud wherein the wearbar and stud are placed in position over a damaged wearbar or against the boiler tube in the case of a missing wearbar and the stud end welding technique utilized to fuse the wearbar and stud in place with the damaged wearbar or boiler tube in the case of a missing wearbar in situ. An arc shield is utilized which has a projection from the weld fillet cavity thereof which cooperates in conjunction with the aperture of the retrofit wearbar to provide alignment of the stud in the wearbar and prevent shorting of the stud to the wearbar during the welding cycle.

Abstract: Stud-welding device and procedure to mold a stud to a workpiece, adapted to weld studs with different dimensions, changing continuously, using an automatic stud-welding device, the device being mechanically fed studs in a stud holder, individually and in the correct position, and the stud holder being held by the stud-welding device, guided to the welding position, and the stud is welded to the workpiece, after which the stud-welding device returns the stud holder to the transfer position, in order to take on another stud and to achieve such several stud holders are assigned to the stud-welding device and alternatively connected to the stud-welding device in accordance with a selectable call-up program, so that a given stud-holder, equipped with a stud and connected to the stud-welding device, is separated from the stud-welding device after the weld has been performed thereon and the transfer position has been reached and held in that location, the operating sequence being controlled electrically or electroni

Abstract: A method and apparatus for improved percussive arc welding is disclosed. In this technique a test arc of a voltage no greater than the initiating voltage of the percussive arc welding is first applied across the pieces to be welded. The welding cycle is then performed if, and only if, an arc is detected responsive to the impressing of the test voltage.

Abstract: The disclosure concerns an electrical stud-welding device with a welding head and a stud holder fastened thereto in a detachable manner. The stud-welding device is of the type that can be regulated with respect to various welding parameters, such as charging voltage, capacitance, plunge velocity, weld current, weld time, and plunge damping and providing means for weld studs of different dimensions without the need to perform test welds, thus also allowing automatic change of the stud holder, by designing the stud holder as a data carrier for several specific, variable welding-parameters, and data-acquisition units which can be acted upon by the stud holder arranged on the stud-welding device and a central, device-specific data-processing unit associated with the stud-welding device, and provided for the acquired data, which unit sets the controlled variables in accordance with the data that were determined.

Abstract: Apparatus and methods for replacing or repairing missing or damaged abrasion resistant wearbars utilized in high velocity cyclone boilers. A retrofit wearbar having an aperture therein is utilized in conjunction with an end weldable stud wherein the wearbar and stud are placed in position over a damaged wearbar or against the boiler tube in the case of a missing wearbar and the stud end welding technique utilized to fuse the wearbar and stud in place with the damaged wearbar or boiler tube in the case of a missing wearbar in situ. An arc shield is utilized which has a projection from the weld fillet cavity thereof which cooperates in conjunction with the aperture of the retrofit wearbar to provide alignment of the stud in the wearbar and prevent shorting of the stud to the wearbar during the welding cycle.

Abstract: A stud arrangement on casehardened studded chains for motor vehicles, wherein the studs consist of a steel body which is permanently welded to a chain link and provided with a centrally disposed hard metal pin. The hard metal pin is inserted into the steel body such that it is covered on all sides by steel material of a thickness which at least corresponds to the casehardening penetration depth. In a method for producing such studded chains, an inwardly converging blind hole is cut out from one end of the steel body. The hard metal pin, of a shape corresponding to the conical hole, is forced into the hole, the pin being shorter than the blind hole so that a skirt is formed outside the pin. The edge of the skirt is beveled, and the steel body with the metal pin therein is joined to the chain by resistance welding in a machine for welding studs onto chain links, the body with the pin being moved gradually toward the chain link as the beveled edge melts and flows radially outwards.