Abstract: A method and system for pulse welding provides an output pulse waveform. The waveform has at least a frequency from a range of available frequencies not limited to harmonic frequencies. The waveform provides power suitable for welding, and has a plurality of background portions alternating with a plurality of peak portions. A transition down occurs from the peak portion to the background portion with a first acceleration and a transition up occurs from the background portion to the peak portion with a second acceleration. At least one of the first and second accelerations are non-zero over at least most of the transition. The waveform is preferably created by switching an inverter. Both accelerations may be non-zero, and each transition may have two accelerations, one negative closer to the peak, and one positive closer to the background. The accelerations may be constant with opposite polarity. Preferably the process is current controlled during the transitions. The process frequency may be fixed or varying.

Abstract: The present invention includes a welding system that has at least two metal inert gas (MIG) welders configured to perform a cooperative pulsed MIG welding process. The welding system also includes at least one communications link connecting the at least two MIG welders to deliver at least one of subordination commands and superiority commands to either of the at least two MIG welders to synchronize the cooperative pulsed MIG welding process.

Abstract: The present invention is a device for coating surfaces of metallic work pieces with an electrically conductive material by employing short duration high current packets of pulses in which the work piece forms the cathode and the consumable coating material forms the anode, which are connected to a generator for generating pulses by charging and discharging a bank of capacitors using a MOSFET. The invention is also a device for controlling the on and off time of a metal oxide semiconductor field effect transistor (MOSFET).

Abstract: A method and apparatus for multi process welding includes providing a controlled short circuit output and a pulse output in response to a user selection across a workpiece output stud and a torch output stud.

Abstract: A metal cored electrode used to form a weld metal on a workpiece having improved yield strength, tensile strength and impact toughness by the combination of molybdenum, titanium and boron, the electrode containing at least about 0.001 weight percent boron, at least about 0.05 weight percent molybdenum, at least about 0.005 weight percent titanium and a majority of iron, the above metal alloy system having an average yield strength of at least about 70 ksi and an average tensile strength of at least about 90 ksi.

Abstract: An arc welding control method carries out weld with a welding current and a welding speed different from those at a steady welding period according to intrinsic resistivity of a weld wire or a base material at a welding start period and a welding end period, so as to obtain a satisfactory welding quality.

Abstract: A welding power supply including power conversion circuitry adapted to receive a primary source of power, to utilize one or more power semiconductor switches to chop the primary source of power, and to convert the chopped power to a welding output is provided. The provided welding power supply includes a pulse width modulated (PWM) digital controller including gate drive circuitry that generates a PWM output signal that controls the switching of the one or more power semiconductor switches. The PWM output signal includes a duty cycle term corrected for one or more sources of error in the welding system.

Abstract: An electric arc welder for creating a welding process in the form of a succession of AC waveforms between a particular type of cored electrode, with a sheath and core, and a workpiece by a power source comprising a high frequency switching device for creating the individual waveforms in the succession of waveforms, each waveform having a profile is formed by the magnitude of each of a large number of short current pulses generated at a frequency of at least 18 kHz where the profile is determined by the input signal to a wave shaper controlling the short current pulses; a circuit to create a profile signal indicative of the particular type of electrode; and a select circuit to select the input signal based upon the profile signal whereby the wave shaper causes the power source to create a specific waveform profile for the particular type of cored electrode.

Abstract: A method and system with a welding torch having a contact tip which has an upper portion and a lower portion, where the upper portion and the lower portion are electrically isolated from each other and each of the upper portion and the lower portion make contact with the same electrode during a welding operation. A first power supply is coupled to the upper portion which provides a first current to the upper portion during the welding operation, and a second power supply is coupled to the second portion which provides a second current during the welding operation. The first and second currents are accumulated in the electrode during welding to provide a welding waveform. The first power supply can have a higher inductance than the second power supply.

Abstract: A system and method is provided in which a welding system modulates the heat input into a weld joint during welding by changing between a high heat input welding waveform and a low heat input welding waveform. The system can utilize detected weld joint geometry and thickness to vary the utilization of the high heat and low heat waveform portions to change the weld bead profile during welding. Additionally, the wire feed speed is changed with the changes between the high heat input and low heat input portions of the welding waveform.

Abstract: An arc welding system includes a power converter that outputs a welding waveform based on a welding signal. The power converter is operatively connected to a welding torch to create an electrical arc between the welding torch and a workpiece based on the welding waveform. The arc transfers at least one drop of molten material onto the workpiece. The arc welding system also includes magnetic field system includes a magnetic field generator that generates a magnetic field based a magnetic steering signal and a controller that is operatively connected to the power converter and the magnetic field controller. The controller controls operations of the power converter according to the welding signal and simultaneously controls the magnetic field system according to the magnetic steering signal. The welding signal includes a peak portion and a background portion for each waveform cycle, and the magnetic steering signal includes a peak portion.

Abstract: A method for root pass welding steel plate and pipe is provided that uses pulse arc welding having a current pulse waveform exhibiting a low constant background current and fixed frequency. The welding process may be performed without a backer or backing material.

Abstract: Methods and systems for creating and controlling an AC output for welding, plasma cutting or heating are provided. One embodiment of the present disclosure achieves a desired square wave AC output and reduces the number of circuit components needed by combining components of a buck converter and a full bridge inverter. Current flow paths through a power control circuit that are generated via switching of transistors in the circuit on and off are provided. In one embodiment, a pulse width modulation leg, which controls the level of current flow through an inductor, is provided. Certain embodiments include a bidirectional buck converter that converts an unregulated DC flow to a regulated DC flow through an inductor. In one embodiment, a steering leg is provided, which controls a direction of current flow through the inductor. Additionally, an output clamp circuit, which suppresses the parasitic load inductance during polarity reversal is provided.

Abstract: A method and apparatus for welding is disclosed. The output is preferably a cyclical CV MIG output, and each cycle is divided into segments. An output parameter is sampled a plurality of times within one or more of the segments. The CV output is controlled within the at least one segment in response to the sampling. The parameter is output power, a resistance of the load, an output current, an output voltage, or functions thereof in various embodiments. The control loop is preferably a PI or PID loop. The loop may be applied only within a window. The set point may be taught or fixed. The system can be used to weld with a controlled arc length.

Abstract: An improvement in a welder including a power source for performing a TIG welding process across an electrode and a workpiece where the power source has a first output lead connected to the electrode and a second output lead connected to the workpiece with a controller for creating a waveform across the power leads. The waveform has a profile alternating between a first current section and a second current section at a given overall frequency and the sections each have a peak current in either the positive or negative direction and a duration. The improvement comprises at least one of the current sections being pulsed between a high current level equal to its peak current and a low current level in the opposite direction of the peak current at a pulsing frequency greater than the given overall frequency.

Abstract: A controller for a welding system adapted to determine a value of a weld secondary parameter across a weld secondary component based on a sensed parameter is provided. The controller may also be adapted to compare the determined value to a reference value range and to alert a user to a presence and location of a weld secondary error when the determined value is outside the referenced value range.

Abstract: A structural skeleton of a nuclear fuel assembly is assembled by inserting guide tubes through a plurality of spacer grids, and performing pulse arc welding to connect the inserted guide tubes and the spacer grids. In the structural skeleton, the spacer grids may comprise intersecting grid straps, and at least some of the grid straps may include tabs that are pulse arc welded to guide tubes. The structural skeleton may include grid retaining rings installed on the guide tubes and pinning some spacer grids, with the grid retaining rings being pulse arc welded to guide tubes. A fuel assembly includes the structural skeleton, a plurality of fuel rods comprising fissile material passing through the spacer grids, and upper and lower end fittings secured to upper and lower ends, respectively, of the guide tubes.

Abstract: Disclosed is a consumable electrode arc welding in which short-circuit welding is performed by alternating short-circuits and arcs while a welding wire is fed automatically. In this method, a short-circuit state and an arc state are alternately generated by feeding the welding wire in periodically alternating forward and backward directions at a predetermined frequency and a predetermined velocity amplitude with reference to a basic wire feed speed based on a set current. The speed of periodic feeding of the welding wire is controlled in such a manner that the waveform to feed the welding wire is different between the forward and backward directions.

Abstract: A three stage power source for an electric arc welding process comprising an input stage having an AC input and a first DC output signal; a second stage in the form of an unregulated DC to DC converter having an input connected to the first DC output signal, a network of switches switched at a high frequency with a given duty cycle to convert the input into a first internal AC signal, an isolation transformer with a primary winding driven by the first internal high frequency AC signal and a secondary winding for creating a second internal high frequency AC signal and a rectifier to convert the second internal AC signal into a second DC output signal of the second stage, with a magnitude related to the duty cycle of the switches; and, a third stage to convert the second DC output signal to a welding output for welding wherein the input stage has a regulated DC to DC converter with a boost power switch having an active soft switching circuit.

Abstract: An arc welding power source supplies a start current, a welding current and a crater current as an output current in accordance with an activating signal supplied from outside. The power source includes a start period setting unit, a crater period setting unit, and a current control unit that controls the output current. The current control unit causes the power source to supply the start current and the welding current consecutively while the activating signal is in an on-state, where the start current is supplied for the start period, and the welding current is supplied for the period following the start period. The current control unit also causes the power source to supply the crater current after the activating signal is turned off, where the crater current is supplied for the crater period.

Abstract: A TIG welder and methodologies for providing an output welding current in a welding circuit. The welder has main and background power supplies. The main supply has an SCR network which selectively connects a transformer secondary winding to the welding circuit according to SCR control signals. The background supply is connected to the SCR network, which selectively connects the second power supply to the welding circuit according to the SCR control signals. The SCR network may have first and second SCRs operating according to first and second SCR control signals from a control circuit, where the control circuit is connected to the SCR network and the second power supply and selectively connects the SCR control signals to the SCR network according to the setpoint current value.

Abstract: A welding apparatus having a system to facilitate its assembly. The apparatus is assembled by affixing a pair of molded end panels to a molded base and each of the end panels has a specially constructed receptacle area that is adapted to receive an end of the base. Each end of the base has a pair of snaps that extend outwardly and which engage with a correspondingly located pair of ramps formed in the receptacle area of each of the end panels. Thus the assembly is easily carried out by simply inserting the base ends into the receptacle areas where the snaps ride up the ramps and engage the vertical walls on the inner side of those ramps to securely affix the end panels to the base. Preferably the snaps are U-shaped in configuration with the distal end of the snaps being the closed ends of the U-shaped snaps.

Abstract: A TIG welder and methodologies for providing an output welding current in a welding circuit. The welder has main and background power supplies. The main supply has an SCR network which selectively connects a transformer secondary winding to the welding circuit according to SCR control signals. The background supply is connected to the SCR network, which selectively connects the second power supply to the welding circuit according to the SCR control signals. The SCR network may have first and second SCRs operating according to first and second SCR control signals from a control circuit, where the control circuit is connected to the SCR network and the second power supply and selectively connects the SCR control signals to the SCR network according to the setpoint current value.

Abstract: Systems, devices, and methods for measuring a peak to peak switching ripple in a voltage present on welding output terminals are provided. The systems, devices, and methods may also be utilized to determine, during a welding operation, a weld cable inductance based on the measured peak to peak voltage ripple.

Abstract: A consumable electrode type arc welding method for generating arc between a plate-shaped work and a welding wire by a mixed shield gas including argon gas to weld the plate-shaped work, includes: making a state of reverse polarity in which the polarity of the welding wire is positive at the welding start time, and switching at least once to a state of positive polarity in which the polarity of the welding wire is negative.

Abstract: A system and method is provided in which each of a GMAW power supply and a TIG/plasma power supply are utilized in a common weld joint, where the waveforms from each of the power supplies are pulsed waveform which are pulsed out of phase which each other. Such a system minimizes arc interference and arc blow while at the same time increasing travel speed and throughput of a welding operation.

Abstract: An electric arc welder for depositing weld metal along a groove between two edges of a metal workpiece where the welder comprises a first electrode driven by a first wire feeder toward a point in said groove, a second electrode driven by a second wire feeder toward the point and a main power source with a first output terminal connected to the first electrode and a second output terminal connected both to the second electrode and directly or indirectly to the metal workpiece to create a second electrode path and a workpiece path. The power source includes a high speed switching output stage for creating current with a selected AC waveform between the first and second output terminals where the waveform of the main power source is generated by a waveform generator controlling a pulse width modulator circuit to determine the current operation of the output stage.

Abstract: A method and apparatus for welding include initiating a pulse welding process includes initiating a welding arc by providing CC type welding power, maintaining the arc by providing CV type power. Then, pulse type welding power is provided. The method and system can be used to start short circuit, or other welding processes by providing short circuit power, or welding power of a given mode, instead of providing pulse power. Also, in one alternative, a method and system of initiating a pulse, short circuit, or given welding process includes initiating a welding arc by providing CC type welding power at least until a pseudo-equilibrium for the arc is established. Then, providing welding power in a pulse, short circuit, or the given mode.

Abstract: A TIG welder and methodologies for providing an output welding current in a welding circuit. The welder has main and background power supplies. The main supply has an SCR network which selectively connects a transformer secondary winding to the welding circuit according to SCR control signals. The background supply is connected to the SCR network, which selectively connects the second power supply to the welding circuit according to the SCR control signals. The SCR network may have first and second SCRs operating according to first and second SCR control signals from a control circuit, where the control circuit is connected to the SCR network and the second power supply and selectively connects the SCR control signals to the SCR network according to the setpoint current value.

Abstract: A welding operation is performed by moving or rotating an arc in a welding torch, and feeding a metal cored wire through the torch in a direct current, electrode negative welding process. The electrode may include one or more arc stabilizers. The welding process may be pulsed or non-pulsed. Moreover, the process may be used with a number of different base metals intended to be welded, such as thin plate, galvanized metals, painted metals, coated metals, and so forth.

Abstract: A welding power supply including power conversion circuitry adapted to receive a primary source of power, to utilize one or more power semiconductor switches to chop the primary source of power, and to convert the chopped power to a welding output is provided. The provided welding power supply includes a pulse width modulated (PWM) digital controller including gate drive circuitry that generates a PWM output signal that controls the switching of the one or more power semiconductor switches. The PWM output signal includes a duty cycle term corrected for one or more sources of error in the welding system.

Abstract: Welding power is generated by first generating two different current waveforms, and comparing the waveform values for control intervals to select which waveform provides the greater current. The waveforms are for different transfer modes, such as one for a pulsed arc portion, and another for a short-circuit transfer mode or for short-circuit clearing. The waveforms may be programmed by settings in a state machine. A balance or relative prioritization in the comparison may be influenced by user inputs. The resulting hybrid process has aspects of both spray transfer and short-circuit transfer modes.

Abstract: A system and method is provided in which a surface tension transfer welding function is employed where the welding waveform switches polarity during welding when a short circuit event is detected.

Abstract: A pulsed waveform welding operation is implemented by reference to a commanded wire feed speed set by an operator. The wire feed speed is set on a wire feeder, and a signal representative of the commanded wire feed speed is applied to a power supply. The power supply control circuitry references a look-up table in which pulsed waveform parameters are provided based upon wire feed speed. The parameters may include multiple parameters such as pulse frequency, peak current, background current, and current ramp rates. The control circuitry commands power conversion circuitry to generate the commanded waveform as a function of the commanded wire feed speed.

Abstract: The invention relates to a welding method for implementing and monitoring a welding process, whereby a power source (2) and a feeding device (10) for the welding rod (11) are controlled by means of a control device (4), and whereby at least one control variable is measured or calculated from characteristic variables of the arc during the welding process.

Abstract: A method and a system to increase heat input to a weld during an arc welding process. A series of electric arc pulses are generated between an advancing welding electrode and a metal workpiece using an electric arc welding system capable of generating an electric welding waveform to produce the electric arc pulses. A cycle of the electric welding waveform includes a pinch current phase providing an increasing pinch current level, a peak current phase providing a peak current level, a tail-out current phase providing a decreasing tail-out current level, and a background current phase providing a background current level. At least one heat-increasing current pulse of the cycle is generated, providing a heat-increasing current level, during the background current phase, where the heat-increasing current level is above the background current level. The cycle of the electric welding waveform with the at least one heat-increasing current pulse may be repeated until the arc welding process is completed.

Abstract: A controller for a welding system adapted to determine a value of a weld secondary parameter across a weld secondary component based on a sensed parameter is provided. The controller may also be adapted to compare the determined value to a reference value range and to alert a user to a presence and location of a weld secondary error when the determined value is outside the referenced value range.

Abstract: A method and a system to control heat input to a weld during an arc welding process. A series of electric arc pulses are generated between an advancing welding electrode and a metal workpiece using an electric arc welding system capable of generating an electric welding waveform to produce the electric arc pulses. The welding waveform has droplet transfer pulses and at least one heat input pulse which is generated during a background portion of the waveform. The at least one heat-increasing current pulse is above the background current level and has a polarity opposite of that of the droplet transfer pulse.

Abstract: A control method for AC pulse arc welding performed upon application of cyclic AC welding current is provided. The welding current has a cycle including an electrode negative polarity period and an electrode positive polarity period subsequent to the electrode negative polarity period. In the control method, an electrode negative polarity base current and a subsequent electrode negative polarity peak current are applied during the electrode negative polarity period. The electrode negative polarity base current has an absolute value smaller than a first critical value, and the electrode negative polarity peak current has an absolute value greater than the first critical value. Then, an electrode positive polarity peak current is applied during the electrode positive polarity period. The electrode positive polarity peak current has a value greater than a second critical value.

Abstract: An electric arc welder includes a short detecting circuit for creating a short signal upon occurrence of a short circuit between an advancing electrode and a workpiece, and a boost circuit to create a plasma boost pulse after the short circuit is cleared during the time period when the welder is not outputting a peak pulse current.

Abstract: A welding system or an enterprise using welding systems can communicate with cloud-based resources for the provision of services and products to facilitate the welding operations. The communications may be via wired or wireless media, and may be direct, or through other components, such as enterprise networks, peripheral devices, and so forth. The cloud-based resources may provide for storage of data, particularly welding data, processing of data, welding protocols, specifications and processes, financial transactions for the purchase, licensing or use of welding-related products and services, welding training, and so forth.

Abstract: Methods and systems for resistance spot welding using direct current micro pulses are described. One described method comprises comprising forming a weld joint by applying a plurality of direct current micro pulses to at least two pieces of materials through a first electrode and a second electrode.

Abstract: A welding control apparatus includes an integrator for starting calculation of a voltage error integral value Sv2 when a first pulse period ends and a second pulse period starts in a pulse cycle, based on various data. The apparatus also includes a comparator for comparatively determining whether a value of the voltage error integral value Sv2 provided as the calculation result has become 0, and a waveform generator for terminating the relevant pulse cycle and starting a next pulse cycle when the value of the voltage error integral value Sv2 is 0. Where Sv2=?{Ks(Io2?Is2)+Vs2?Vo2}dt??(1).

Abstract: A welding system is provided, in which two electrodes are directed at a joint between two work pieces and the electrodes are energized with DC pulse or AC welding waveforms at a controlled waveform phase angle. The systems include a synchronizing controller to synchronize the welding waveforms, and a work point allocation system provides one or more work point values to the welding machines to provide synergic control of the welding according to a user selected system work point value or parameter. The systems and methods further provide for synchronized work point value modulation for the opposite sides of a dual fillet weld. The system and method further provide a high energy heat source that directs intense heat at a portion of the weld joint to improve weld penetration.

Abstract: A tandem pulse arc welding control apparatus includes a voltage detector; a voltage setting unit; a pulse-peak-current-reference-value setting circuit; a pulse-base-current-reference-value setting circuit; an error amplifier that calculates a pulse-peak-current variation value and a pulse-base-current variation value; an adder that calculates a pulse-peak-current value; an adder that calculates a pulse-base-current value; a pulse-waveform selection circuit that outputs the pulse-peak-current value in a pulse peak period, and that outputs the pulse-base-current value in a pulse base period; and an output control circuit that controls a current value for a second welding wire. Because an appropriate welding voltage can be obtained with this configuration, a high welding quality can be realized.

Abstract: An electric arc device and methods to build up, clad, join, or overlay an alloyed metal onto a parent metal with minimal admixture. The methods employed in the electric arc device provide a high frequency waveform with a high amplitude pulse, a low amplitude background current, and a special shorting routine, to alleviate the problem of generating too much ad-mixture. A fast transition from a peak current level to a background current level along with a shorting response and a plasma boost pulse reduces the droplet size and reduces the heat input required to achieve good welding performance.

Abstract: A pulse arc welding method is provided for performing welding by causing welding current to flow through a welding wire and a base metal via a power supply tip. The welding current has a pulse cycle made up of a first peak time, a second peak time and a base time. A first peak current is applied during the first peak time, a second peak current, smaller than the first peak current, is applied during the second peak time, and a base current is applied during the base time. When a tip-base distance between an end of the power supply tip and the base metal is smaller or greater than a reference value, the first peak current is increased or decreased in accordance with the difference between the reference value and the tip-base distance.

Abstract: The invention comprises a set of methods to detect the resistance of a connection to safety ground and to detect the presence of voltage hazardous to people in systems where an unknown amount of current intermittently flows in the safety ground circuit. Samples of voltage between two points in the safety ground circuit are taken repeatedly. When the voltage caused by the unknown currents in the safety ground circuit is below a preset threshold, a known current is applied and another voltage sample is taken to detect the electrical resistance of the safety ground circuit. If an excessive resistance or voltage is detected, one or more outputs are activated or deactivated to indicate the problem and remove power from the system. The invention requires no current sensor for its operation.

Abstract: A pulse welding welder is provided which provides a pulse welding waveform to a workpiece to be welded. The welding waveform has a plurality of welding cycles and each of the cycles has a droplet transfer peak pulse and a background portion with a first polarity and an opposite polarity portion which precedes the droplet transfer peak pulse and is after the background portion.

Abstract: The present invention provides a welding control apparatus including: a droplet separation detecting unit that detects separation of a droplet from a tip end of welding wire; and a waveform generator that alternately generates a first pulse for separating the droplet and a second pulse for shaping the droplet and outputs the generated pulse to a welding power source, the waveform generator generating a third pulse having a pulse shape different in a pulse peak current and/or a pulse width from the second pulse to output the generated third pulse to the welding pulse source after a base time of the first pulse if separation of the droplet is not detected within a peak period, a falling slope period, or a base period of the first pulse to thereby restore a droplet supply regularity.