New progressive method of electroslag melting of vessel nozzles for NPP

Described is the electroslag remelting of connection pipes up to 400 mm in diameter which excludes their hand welding to item. Copper water-cooled mould is secured to an item at points where a connection pipe is to be formed and molten flux is poured into said mould. Next, a consumable electrode of an alloy close in composition to the material of the item is introduced into the mould, and the connection pipe is cast by remelting. Said technique was developed in application to connection pipes of HPR reactor steam separator and of WWR- 440 reactor volume compensator. Metallographic studies, mechanical tests and inspection of 22K steel connection pipes and of their joints with the body have shown that their quality meets fully the requirements placed upon items of nuclear power generation equipment