Patent Number: 047724480
Section: 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. The crimpable section is crimped to engage recesses provided in the pin whereby relative rotation therebetween is positively prevented. A locking nut retainer may optionally be provided for positively retaining the nut in position around the support pin which has a crimpable split cylindrical wall portion and an axial slot, and tabs. The retainer is compressed for insertion into a bore in a structural member, the bore having an annular recess for accommodating the tabs whereby the retainer is positively retained in the structural member and the wall portion is crimped to engage the nut.