Patent Number: 054065968
Section: abstract

The device includes a removable supporting end piece (26) which comes to rest on the top end part of a support assembly (21) fixed to the end of a port adapter of the head of the vessel of a nuclear reactor, and a pressure plate (28) including an odd number of lifting screws (31), so as to move the instrumentation column (22) upward and to clamp it against a support surface (24). A tightening assembly (35) for the lifting screws includes a tightening spindle (42a) having an end part (45) shaped to receive a tool (40) for rotating the spindle, and in turn rotates tightening spindles mounted so as to idle in the mounting plate (38) of the tightening assembly (35). The tightening spindles comprise shaped end parts (46a) coming into engagement with drive parts (31b) of the lifting screws (31) of the pressure plate (28), so as to tighten all the lifting screws simultaneously.