What is the relationship between arc length and voltage?
The voltage and arc length are closely related. The shorter the arc, the lower the arc voltage and the lower the temperature produced, an as the arc lengthens, the resistance increases, thus causing a rise in the arc voltage and temperature.
What is arc voltage?
Arc Voltage is that amount of voltage that exists on contacts separated by a small gap that will cause an electric discharge across the gap. Depending on the severity and duration of the arc, each time an arc ignites, contact erosion occurs.
What is arc voltage in welding?
Gases. 2 VOLTAGE Arc voltage is the voltage between the end of the wire and the workpiece. Because of voltage drops encountered in the welding system, the arc voltage cannot be directly read on the power source voltmeter.
What is the effect of current and voltage on welding?
The welding variable that has the greatest effect on the degree of weld penetration is current (measured in amperage or amps). Quite simply, as welding current increases (i.e., more amperage), weld penetration increases and as welding current decreases (i.e., less amperage), weld penetration decreases.
What happens to the relationship between current and voltage of arc length is increased?
As the arc length increases proportional to an increase in voltage, the electrode extension, distance from the contact tip to the point where the welding wire is melting in the arc, consequently decreases, Figure 3.
What is the relationship between length and current?
Ohm’s Law tells us that V=IR. This implies that I∝1R. But, R∝l, where l is the length of the conductor.
Which electrode gives high arc voltage?
Cellulosic electrodes: produce a gas shield high in hydrogen raising the arc voltage.
What is arc voltage directly related to?
4.3 Plasma-arc cutting
| Metal thickness | Plasma gas | Shield gas |
|---|---|---|
| 3 | Air | |
| 6.5 | Air | |
| 6.5 | N2 | CO2 |
| 6.5 | Ar + H2 |
Which current is used in arc welding?
Arc welding uses both direct and alternating current. A step down transformer is used to get the alternating current for arcs. The transformer gets its current from the main supply but needs to go down to 80 to 100 volts.
How much current is required for arc welding?
Both AC and DC can be used in the arc welding. Usually, 70 – 100 V on AC supply and 50 – 60 V on DC system is sufficient to strike the arc in the air gap between the electrodes. Once the arc is struck, 20 – 40 V is only required to maintain it. The current rating is usually 50 – 1000 A.
Which current is used for arc welding?
Both direct current (D.C.) and alternating current (A.C.) are used for arc welding. The alternating current for arc is obtained from a step down transformer. The transformer receives current from the main supply at 220 to 440 volts and step down to required voltage i.e., 80 to 100 volts.
What voltage affects welding?
Welding voltage primarily controls the arc length which is the distance between the molten weld pool and the wire filler metal at the point of melting within the arc. As the voltage is increased, the weld bead will flatten out more and have an increasing width-to-depth ratio.