Development of Optimum Welding Heat Input Device Based on Welding Frequency and Spark Detection

According to the previous researches, the welding frequency increases as the load impedance decreases when the narrow gap shorts out during ERW welding process. The proper welding frequency is theoretically calculated and also measured for OCTG pipe manufacturing. Also, to assure the quality of ERW tube, the spark detection device developed. According to signals from the spark detection device, there are two types of sparks found as a single-shot spark and sustainable spark. The formation of single-shot spark is too short to recognize the existence of spark with operator’s naked eyes during ERW process. Thus, the paint spraying system was used to mark the sparking location for screening at the inspection unit. Therefore, spark detecting devices (bad signal detection) are used to increase the productivity of products and improve its quality. In addition, the database server system developed according to the accumulated data can provide the cost savings and the creation of new demands.