一、大口径焊接锅炉管发展概况美、法、日、苏等国在发展大容量火电机组时都遇到如何解决大直径的主蒸汽导管、再热蒸汽导管的问题。对于高压的主蒸汽导管他们都是采用卧式水压机引伸或锻造方法。近年美、苏还研究电渣重熔、离心铸造法生产大口径钢管。对于承受中压的大直径再 First, the large-diameter welded boiler tube development profile The United States, France, Japan and the Soviet Union and other countries in the development of large-capacity thermal power units have encountered how to solve the large diameter of the main steam duct, reheat steam duct problems. For high-pressure main steam pipe they are using horizontal hydraulic press extension or forging method. In recent years, the United States, the Soviet Union also study the electroslag remelting, centrifugal casting method of producing large diameter steel pipe. For large diameter to withstand medium pressure then