REPORT ON THE FIRST NPD-1 SINGLE ELEMENT IRRADIATION AND FAILURE

Technical Report · Thu Aug 01 04:00:00 EDT 1957

OSTI ID:4353264

Howieson, J

An NPD fuel rod was intended to consist of a bundle of 19 elements each 0.504 in. UO/sub 2/ diameter, clad in 0.027 in. Zircaloy-2, and 8 ft 9 in. long. This first test was of a single one of these elements under conditions approximating the most severe to be encountered in the reactor. The test was carried out in the E-9 rod position of the NRX Reactor. The heat was removed from the elemert by high pressure, high pressure water circulated in the loop system. The irradiation started on January 18 and proceeded as planned. On February 26 a hole appearod through the sheath. One of the series of tests called for the operation of a defected rod to observe the activity released in normal operation. The power was lowered to 5 Mw and then raised back to 40 Mw. This caused all the monitors to go off scale. The reactor was shut down and the element removed for examination. It was found that the Zircaloy-2 cladding had corroded and in one place at the center of the rod had corroded completely through and exposed fuel. (W.L.H.)

• Research Organization: Atomic Energy of canada Ltd. Chalk River Project, Chalk River, Ont.
• NSA Number: NSA-12-007571
• OSTI ID: 4353264
• Report Number(s): CRNE-744; AECL-552
• Country of Publication: Canada
• Language: English

Related Subjects

CANNING
CORROSION
FAILURES
FUEL ELEMENTS
IN PILE LOOPS
IRRADIATION
NPD
NRX
PHYSICS
PRESSURE
RADIOACTIVITY
REACTORS
URANIUM DIOXIDE
WATER COOLANT
ZIRCALOY