Nuclear fuel preheating system

Claim 2

An improved nuclear reactor fuel handling system of the type having a transporter which conveys a new nuclear fuel assembly with coolant channels longitudinally therethrough through an isolation chamber into the nuclear reactor containment building, wherein the improvement comprises: a. a heating station located in said isolation chamber for heating said fuel assembly from one end by passing heated fluid through the length of said fuel assembly; and b. a transfer container mounted on said transporter for transporting said fuel assembly through said isolation chamber and into registry with said heating station, said transfer container adapted to carry said fuel assembly on its interior and said transfer container having a bottom plate with at least one perforation for allowing the passage of a fluid therethrough.

Claim 3

The improved nuclear reactor fuel handling system as recited in claim 1 wherein said transfer container has a length at least equal to the length of said fuel assembly and wherein said heating station includes: a. a pump having a suction side and a pressure side; b. a first duct connected to said pressure side of said pump and adapted to terminate in close registry with one end of said transfer container and adapted to have an outlet end which matches the cross sectional shape of said transfer container; c. heating elements located within said first duct for preheating the circulatEd fluid; and d. a second duct connected to said suction side of said pump and adapted to originate in close registry with the other end of said transfer container and adapted to have an inlet end which matches the cross sectional shape of said transfer container, whereby heated fluid may be circulated through said fuel assembly from one end to the other thereby assuring that said fuel assembly is heated only from said one end.

Claim 4

The improved nuclear reactor fuel handling system as recited in claim 1 wherein said transfer container is an insulated container and wherein said bottom plate of said transfer container is adapted to sealingly engage with one end of said fuel assembly and wherein said at least one perforation in said bottom plate is adapted to axially align with at least one of said coolant channels longitudinally extending through said fuel assembly.

Claim 5

The improvement as recited in claim 2 wherein said nuclear fuel is of the type in which the fuel of each fuel element is clad with a cladding and the gap between the fuel and the cladding is filled with a heat transfer material which exhibits a solid form at room temperature and a liquid form at reactor refueling temperatures, each fuel element being provided with an expansion chamber at one end of each element to accommodate thermal expansion of the heat transfer material and of the fuel material.

Claim 6

The improvement as recited in claim 2 wherein said isolation chamber contains an inert gas, said gas comprising the fluid which is heated and directed through said fuel assembly.