The polarity and its influences on the usability quality of submerged arc welding were reviewed. The results show that The arc shape is different during DCEP and AC

the metal transfer type is not completely changed by polarity

but the droplet diameter and droplet detachment frequency are different. Although the polarity has some influence on the porosity of submerged arc weld

but the control of moisture in the flux is the most important measures to prevent porosity. The polarity significantly affects the weld geometry

there are HAZ and dilution values in straight polarity are less than in reverse polarity

but since the fluxes used are not the same

different results may be produced. The influence of polarity on the mechanical properties of weld metal of SAW is quite complex. In the waveform control technology

variable polarity submerged arc welding power can significantly improve the deposition efficiency and welding speed

easy to control the penetration and weld shape

to bring a new concept of submerged arc welding field.