Abstract: An improved plugging system for plugging chamfered flow ports of small diameters in the core barrel of a pressurized water nuclear reactor is disclosed herein. The system is comprised of improved core barrel plugs that are telescopically contractible to facilitate installation, as well as a handling tool having a compact hydraulic ram and plug-holding cradle that is easily manipulable in the limited access space between the core barrel and thermal shield of the reactor for inserting and expanding the plugs into sealing engagement with the core barrel flow ports. The plugs of the system are formed from a generally cylindrical plug body that is radially expandible, and a retaining ring that is telescopically engaged around the plug body which allows it to be slid toward the middle of the plug prior to installation in order to minimize the overall length of the plug prior to the insertion operation.

Abstract: A support pin system which is a non-welded system for fastening a first structural member, such as a nuclear reactor control rod guide tube flange, to a second structural member, such as nuclear reactor upper core plate, includes a support pin and nut. A first pin portion passes through the first member and has a threaded section which mates with the nut. A second pin portion has a solid body section and a split-leaf base section which biasingly engages a bore in the second member. The solid body section is accommodated by a close clearance fit. The split-leaf base section has an intermediate diameter which is less than the diameter of the solid body section. Thus, loads applied transversely to the system are reacted substantially in pure shear through the solid body section. The nut may be a locking nut having a crimpable cylindrical section integrally connected to an internally threaded section.

Abstract: The invention comprises a core barrel plug capable of being remotely installed in a port of a core barrel of a pressurized water nuclear reactor for converting the reactor from a by-pass downflow configuration to a by-pass upflow configuration. The plug comprises a body having an expandable cylindrical portion with a movable mandrel disposed in the body. Remote fluid pressurization causes the mandrel to be advanced thus expanding the body into contact with the port. The plug also comprises a locking mechanism to prevent inadvertent release of the plug.