Automatic Welding Repair Technology for Four Major Types of Pipelines in China’s Coal-fired Power Plants Successfully Put into Use for the First Time

On October 23, the full set of remote-operated pipeline automatic repair equipment and technology was successfully put into use in the reheating steam pipeline system (ASTM A335 P92) repair project of Jiangsu Guohua Chenjiagang Power Co., Ltd. under CHN Energy. The welding seams were verified to be qualified after just one-time operation. This was the first time that the automatic welding repair technology for four major types of pipelines was applied in China’s coal-fired power plants.

The technology is an outcome of the research project “full life cycle-based ultra-supercritical generation unit intelligent welding and repair key technologies research and engineering application” jointly undertaken by the Jiangsu branch of CHN Energy and Suzhou Nuclear Power Research Institute. Based on intensive module design, they worked out a set of performing mechanism applicable for preheating pipe welding in limited spaces. It features functions such as walking, integrated two-way wire feeding, AVC tracking, swaying, wire heating, intelligent cooling, anomaly detection, clamping and locking, waling ABS, and hard cutoff, ensuring the safe, stable, and efficient operation of equipment. Through collaborating with core controllers, it can achieve precise, looped output of welding parameters, multi-pulse coupling control, multilayer and multichannel welding control and self-examination, and automatic calibration. Moreover, with the help of the remote visual system, it can achieve real-time remote control, and monitor and record all kinds of welding parameters, so as to monitor and control the welding pool through video in the entire process. This technology boasts a high degree of flexibility in application, and can significantly reduce labor intensity, eradicate the interference of human factors, and enhance the efficiency and quality of equipment overhaul and repair.

The successful application of the full set of remote-operated pipeline automatic repair equipment and technology marked a breakthrough and upgrade of intelligent repair technology for four major types of pipelines in coal-fired power plants, verified the feasibility and reliability of intelligent automatic welding technology in coal-fired power plant equipment repair, filling in the domestic void in the field. Furthermore, it pushed forward the innovation of energy equipment repair science and technology, and helped innovate power plant generation unit repair modes and accelerate repair technology iterations, pushing coal-fired power plant pipeline repair technology to a new height.