Concept of polarity in arc welding
Arc welding uses three different polarities—Direct Current Straight Polarity (DCSP), Direct Current Reverse Polarity (DCRP) and Alternating Current (AC) polarity, their advantages and disadvantages, effects, choice of polarity, etc. are discussed here. Read detail…
Direct Current Straight Polarity (DCSP) in arc welding
When base metals are connected with positive terminal of the welding power source and electrode is connected with the negative terminal, then the connection is termed DCSP. Advantages, disadvantages and effects of straight polarity on arc welding performance are given here. Read detail…
Direct Current Reverse Polarity (DCRP) in arc welding
When electrode is connected with positive terminal of the power source and base metals are connected with negative terminal, then the connection is termed as DCRP. Advantages, disadvantages and effects of reverse polarity on arc welding performance are given here. Read detail…
Difference between straight polarity and reverse polarity
Differences between straight polarity and reverse polarity in arc welding on various aspects such as connection, performance, penetration, deposition rate, defects, etc. are provided in tabulated form. Read detail…
Alternating Current (AC) or reversing polarity in arc welding
In reversing polarity, base plate becomes positive and electrode becomes negative in one half of cycle; while in next half of the cycle base plate becomes negative and electrode becomes positive. Advantages, disadvantages and effects of reversing polarity on arc welding performance are also discussed here. Read detail…
Comparison among DCEN, DCEP and AC polarities
Differences between straight polarity, reverse polarity and alternating polarity in arc welding are discussed here considering various aspects such as connection, performance, penetration, deposition rate, defects, etc. Read detail…
How polarity affects arc welding performance?
Effects of polarity on filler deposition rate, depth of penetration, reinforcement, width of weld bead, voltage requirement, arc cleaning action, electrode life, arc scattering, various defects like lack of penetration, insufficient melting, inclusions, etc. Read detail…
Oxide cleaning phenomenon in welding
What is oxide cleaning in welding and how it is affected by welding polarity? Surface of base plates may contain one or more unwanted items including dirt, oxide layer, color layer, coating layer, oil or grease, loose foreign particles, etc., which has to be removed prior to welding. Read detail…
Which polarity gives better oxide cleaning in arc welding?
Direct Current Reverse Polarity (DCRP) gives best oxide cleaning action. When avalanche of electrons liberate from work surface, they break the thin non-conductive oxide layer deposited on work surface to make a free passage for flow. Read detail…
Which polarity gives better penetration in arc welding?
With DCSP connection, electrons, liberating from the electrode (negative polarity), are accelerated towards base metal and strike the work surface leading high heat generation on base plate and thus better melting and penetration. Read detail…
Which polarity gives maximum deposition rate in arc welding?
In direct current reverse polarity, electrode is made positive and work is made negative. So avalanche of electrons liberate from work surface and strike electrode at a very high velocity. As a result, more heat is generated at the vicinity of the electrode and hence higher deposition rate. Read detail…