（1. Central Iron & Steel Research Institute, China Iron & Steel Research Institute Group, Beijing 100081, China）（2. China First Heavy Industries, Qiqihaer 161042, China)
Based on the development of nuclear pressure vessel steel and its manufacturing technology for pressurized water reactor in China, the challenges of “l(fā)argescale integrated design” and “high-safety long-term operation” to the property limitation in engineering application of nuclear pressure vessel steel and manufacturing capacity limitation of its equipment were reviewed. The research progress and breakthrough on the manufacturing technologies for heavy forgings of A508-3 steel were introduced on emphasis, containing composition optimizing and matching technique, high purity and uniform metallurgical technique of extra-large steel ingot, near-net-shape forming technique of complicated forgings, as well as combined heat treatment technique for improving the low-temperature toughness and homogeneity of heavy forgings. The technologies as mentioned are the key factors to the high-safety and long-life operation of nuclear power plants. In addition, the development progress and breakthrough on new-generation heavy forgings of A508-4N steel for nuclear pressure vessel were also introduced.