The features of manual downhill welding,semiautomatic welding,automatic welding and other welding technologies like butt flash welding and laser beam welding (LEW) and so on are analyzed.

• 分析了手工下向焊、半自动焊、自动焊及特种焊等焊接方法的特点,在选择焊接方法时应考虑管道直径、壁厚、管道长度、设计条件、管子级别等因素。