Abstract: The metal transfer,welding current,arc voltage and operational performance of the three kinds of self-shielded flux cored wires were studied by using high-speed photography,arc parameters rapid acquisition and analysis system,as well as operational performance test method.The following conclusions have been drawn in this experimental condition,the bridging transfer without arc interruption of self-shielded flux-cored wire can be characterized with the voltage value less than 17.5 V for more than 0.5 ms,and its frequency can also be calculated.The calculated characteristic value t50 which was used to characterize the duration of the transition can be used to describe the quality of bridging transfer without arc interruption of self-shielded flux-cored wire.The quantity and quality of bridging transfer without arc interruption are the main factors to determine the operational performance of self-shielded flux-cored wire.The more the numbers of bridging transfer without arc interruption,the longer the transition duration,the better the operational performance is,which is consistent with the operational performance test results.