Lincoln Electric IM846-A manual Pulse Welding, Current Wave Form Pulse, Pulse-On-Pulse Gmaw-Pp

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OPERATION

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PULSE WELDING

Pulse welding procedures are set by controlling an overall "arc length" variable. When pulse welding, the arc voltage is highly dependent upon the waveform. The peak current, back ground current, rise time, fall time and pulse frequency all affect the voltage. The exact voltage for a given wire feed speed can only be predicted when all the pulsing waveform parameters are known. Using a preset voltage becomes impracti- cal, and instead the arc length is set by adjusting "trim".

Trim adjusts the arc length and ranges from 0.50 to 1.50, with a nominal value of 1.00. Trim values greater than 1.00 increase the arc length, while values less than 1.00 decrease the arc length.

Most pulse welding programs are synergic. As the wire feed speed is adjusted, the Power Wave will automatically recalculate the waveform parameters to maintain similar arc properties.

The Power Wave utilizes "adaptive control" to com- pensate for changes in electrical stick-out while weld- ing. (Electrical stick-out is the distance from the con- tact tip to the work piece.) The Power Wave wave forms are optimized for a 0.75" (19mm) stick-out. The adaptive behavior supports a range of stickouts from 0.50" (13mm) to 1.25" (32mm). At very low or high wire feed speeds, the adaptive range may be less due to reaching physical limitations of the welding process.

Arc Control, often referred to as wave control, in pulse programs usually adjusts the focus or shape of the arc. Wave control values greater than 0.0 increase the pulse frequency while decreasing the background cur- rent, resulting in a tight, stiff arc best for high speed sheet metal welding. Wave control values less than

0.0decrease the pulse frequency while increasing the background current, for a soft arc good for out-of-posi- tion welding.

(See Figure B.3)

FIGURE b.3

CURRENT WAVE FORM (PULSE)

Current

Time

PULSE-ON-PULSE™ (GMAW-PP)

Pulse on Pulse™ is a Lincoln process specifically designed for use in welding relatively thin (less than 1/4"(6.4mm)0 thick) aluminum (See Table B.3). It gives weld beads with very consistent uniform ripple.

In Pulse on Pulse modes, two distinct pulse types are used, instead of the single pulse type normally used in GMAW-P. A number of high energy pulses are used to obtain spray transfer and transfer metal across the arc. Such pulses are shown in Figure B.4. After a number "N" of such pulses, depending on the wire feed speed used, an identical number "N" of low ener- gy pulses are performed. These low energy pulses, shown in Figure B.4, do not transfer any filler metal across the arc and help to cool the arc and keep the heat input low.

"N" PULSES

"N" PULSES

HIGH HEAT

LOW HEAT

PULSES

PULSES

PEAK

 

AMPS

 

BACKGROUND

 

AMPS

 

 

TIME

The Peak Current, Background Current, and Frequency are identical for the high energy and low energy pulses. In addition to cooling the weld down, the major effect of the low energy pulses is that they form a weld ripple. Since they occur at very regular time intervals, the weld bead obtained is very uniform with a very consistent ripple pattern. In fact, the bead has its best appearance if no oscillation of the welding gun ("whipping") is used.(See Figure B.5)

When Arc Control is used in the Pulse on Pulse modes, it does the same things it does in the other pulsed modes: decreasing the Arc Control decreases the droplet transfer and weld deposition rate. Increasing the Arc Control increases the droplet trans- fer and weld deposition rate. Since Arc Control varies weld droplet transfer rate, the Arc Control can be used to vary the ripple spacing in the weld bead.

POWER WAVE 405M

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Contents Safety Depends on You Power Wave 405MCalifornia Proposition 65 Warnings SafetyElectric Shock can kill Iii Welding and Cutting Sparks can Cause fire or explosionPrécautions DE Sûreté IvSAFETYElectromagnetic Compatibility EMC Methods of Reducing Emissions Mains Supply On-Line Product Registration ViiPlease Examine Carton and Equipment For Damage Immediately TAbLE of Contents Information InstallationTechnical Specifications Power Wave 405M Product Ordering Input AC Rated DC Output Weight DimensionsSelect SUITAbLE Location Safety PrecautionsSingle Phase Input Three Phase InputNegative Electrode Polarity Output CAbLES, Connections and LimitationsCAbLE INDUCTANCE, and ITS Effects on Pulse Welding Work Voltage Sensing Power Feed Wire Feeder INTERCON- NectionsVoltage Sensing System DescriptionUP to 4 Feed Heads Allowed Configuring the SystemUP to 4 Wire Feeders Allowed Single Head FeederSystem that is not Auto Mappable 6INSTALLATIONA-6 Alternate Hard Automatic ApplicationTWO Power Waves Welding with Multiple Power WavesInstallation Electric Shock can kill Receptacle SpecificationsDIP Switch Settings and Locations Recommended Processes and Equipment Safety PrecautionsOperation General DescriptionDuty Cycle and Time Period Case Front Layout Power Wave 405MRequired Equipment LimitationsMaking a Weld Nominal ProceduresFringe Procedures Welding AdjustmentsNon Synergic CV Constant Voltage WeldingCurrent Wave Form CV Synergic CVPULSE-ON-PULSE GMAW-PP Pulse WeldingCurrent Wave Form Pulse Smaw Welding Procedures for PULSE-ON-PULSE TAbLE b.2BENEFITS of Pulse on Pulse from Lincoln Electric TIG GtawRecommended Welding Procedures for Power Mode Table b.3 Power ModeOptional Equipment AccessoriesFactory Installed Field InstalledCapacitor Discharge Procedure MaintenancePeriodic Maintenance Routine MaintenanceTROUbLESHOOTING Error code before the machine is turned off Using the Status LED to TROUbLESHOOT System PRObLEMSError Code # Indication Error Codes for the PowerwaveRecommended TROUbLESHOOTING GuidePRObLEMS POSSIbLE Areas Symptoms Misadjustments Course of ActionSymptoms TROUbLESHOOTING Recommended Course of Action PRObLEMSPOSSIbLE Areas of Misadjustments Wiring Diagrams Diagrams Connection Diagram Semi-automatic Simple System Connection DiagramDimension Print Power Wave 405M Precaucion Warnung