1　焊接试验用材料和设备Ｕ型传热管是蒸汽发生器的关键部件 ,它起着隔离和传热的双重作用 ,即在内表面流通的是带放射性的热量较高的一回路工质水 ,在外表面流通的是取自自然界的海水或河水经必要处理的用来产生蒸汽的二回路工质水 ,通过它将一回路水的热能传导给二回路水并使 A welding test materials and equipment U-shaped heat transfer tube steam generator is a key component, which plays a dual role of isolation and heat transfer, that is circulating on the inner surface of the radioactive heat with a higher working fluid water , On the outer surface of the circulation is taken from the nature of the sea water or water through the necessary treatment for the production of steam in the second circuit of working fluid through which the primary circuit water heat transfer to the secondary circuit water and