Anti-rotation element for removing and installing throttling devices (restrictors) in coolant channels of heavy water reactors

摘要

The invention relates to a device for varying the throughput of a tube (2), termed a coolant channel, by means of a throttling device (9) which is mounted in the flow direction at the end of the coolant channel (2) centred in the cover (4) of a reactor pressure vessel (1). The coolant channel extends vertically in a reactor core (3) and is held in its position by a guide bore in a vessel bottom (5). It is provided that the throttling device (9) is a throttling element (9) which is installed in the coolant channel (2) such that it can be screwed out and which has bores (12), and that a groove (14) on the coolant channel (2) accommodates an attached feather (spline) key (13). <IMAGE>