Incore instrumentation cable routing and support element for pressurized water reactor

An apparatus comprising:

• a pressure vessel;
• a nuclear reactor core comprising fissile material disposed in the pressure vessel;
• a core basket disposed in the pressure vessel and containing the nuclear reactor core;
• and
• an incore instrument disposed in a guide tube of the nuclear reactor core and having a cable extending out of the bottom of the nuclear reactor core, making a 180° turn, and extending upward after the 180° turn to a vessel penetration located above the nuclear reactor core and below a top of the pressure vessel.

A method performed in conjunction with a nuclear reactor including a pressure vessel, a nuclear reactor core comprising fissile material disposed in the pressure vessel, a core basket disposed in the pressure vessel and containing the nuclear reactor core, an incore instrument disposed in a guide tube of the nuclear reactor core and having a cable extending out of the bottom of the nuclear reactor core and making a 180° turn, and a bottom support element attached to the bottom of the core basket and defining or including a routing tube that routes the cable of the incore instrument through the 180° turn, the method comprising:

• retracting the cable to move the incore instrument out of the guide tube of the nuclear reactor core and into the routing tube of the bottom support element;
• performing maintenance of the nuclear reactor including replacing the guide tube with a different guide tube;
• and
• re-inserting the cable to move the incore instrument out of the routing tube of the bottom support element and into the different guide tube.