Westinghouse Electric Corporation

Merle A Parker

Hassan J Ahmed

George P Sabol

Stanley S Patrick

Isabel K Lloyd

Richard A Pregnall

Donald W Parker

George F Rice

The present invention is a method of rapidly and reproducibly checking the quality of zirconium base material welds and heat affected zones. In this method, weldment samples are immersed in an elevated temperature fused salt bath for a time period sufficient, at the bath temperature selected, to produce an essentially black oxide film in acceptable quality welds while producing a scaling oxide in unacceptable welds.

Rapid corrosion test for zirconium and zirconium alloy weldments

Nuclear fuel rods are processed to remove moisture in an oven which is evacuated. Measurement of the moisture content in each of a plurality of nuclear fuel rods (typically 44) is carried out by condensing the vapor derived from one randomly-selected control rod in a nitrogen-liquid cooled trap, collecting the condensed vapor in magnesium perchlorate, and determining the weight of the collected moisture. Moisture from the one fuel rod is condensed, collected and has its weight determined repeatedly in increments until the difference between the weight of a last increment and of a just preceding increment is less than 1 mg. (The permissible content is 6 mg. or less.) The rods have small perforations through which the vapor can escape. The evacuating system includes a main evacuating channel connected directly to the oven and a branch channel connected to the one fuel rod through the cold trap. The temperature of, and the vacuum in, the one fuel rod is the same as for the other rods and the residual moisture content after processing must be the same.

Measurement of moisture content

A rod straightness measuring system and method. A rod, such as a nuclear fuel rod, is supported and rotated in such a manner that if the rod were straight, it would be rotated about its longitudinal axis and remain straight without transverse translational motion, and in such a manner that if the rod were cambered, it would remain so cambered while supported and rotated. A multiplicity of separated and fixed range finders are placed apart from and directed towards the rod so that they would be directed perpendicular to a straight rod's longitudinal axis. The range finders measure the distance to the rotating rod. Differences in maximum and minimum measurements for each range finder indicate the degree of straightness of the rod. In a preferred system and method, the range finders are placed at known distances from a straight rod, and differences in distance measurements from the known distances for each range finder indicate the degree of rod straightness.

Nuclear fuel rod straightness measuring system and method

Apparatus and method for testing TIG (tungsten inert gas) welds of end plugs on a sealed nuclear reactor fuel rod. An X-ray fluorescent spectrograph testing unit detects tungsten inclusion weld defects in the top end plug's seal weld. Separate ultrasonic weld inspection system testing units test the top end plug's seal and girth welds and test the bottom end plug's girth weld for penetration, porosity and wall thinning defects. The nuclear fuel rod is automatically moved into and out from each testing unit and is automatically transported between the testing units by rod handling devices. A controller supervises the operation of the testing units and the rod handling devices.

Growing community of inventors

Columbia, SC, United States of America

Merle A Parker