Establishing a connection between steam generator heating surfaces and a collector and/or distributor

摘要

The invention relates to the establishing of a connection between steam generator heating surfaces made of austenitic materials and a collector and/or distributor made of martensitic or ferritic materials or of a nickel-base alloy. In order to extend the expectation of serviceable life of the connection, the pipe nipple of the reservoir used as a collector or distributor is made of a nickel-base alloy and directly welded to the collector wall in such a manner that an axial gap remains between the connecting branch and the collector wall. In a connection of the aforementioned type between steam generator heating surfaces made of austenitic materials and the pipe nipple or the pipe nipple and the collector made of martensitic materials, the coefficient of expansion of the material of the pipe nipple has a particularly good effect upon the serviceable life of the entire connection.