Abstracts Health Sciences

A study of the thermal characteristics of x-ray tube housings

by John Walter Stovall

The relationship of x-ray tube housing temperature to duty cycle was studied for a superficial therapy x-ray installation, a dental radiographic installation, and a rotating-anode medical diagnostic installation. Thermistors were used to measure the tube housing temperature at points selected to be representative of thermal conditions on the surface of the x-ray tube housing. Measurements were made for continuous operation and intermittent operation, for the beam directed horizontally, and for the beam directed vertically down. Maximum temperatures were observed on the uppermost surfaces of the tube housings and minimum temperatures were observed on the lower surfaces of the tube housings. The orientation of the tube housing was found in some cases to alter the maximum tube housing temperature. Theoretically, tube housing temperatures for continuous and intermittent operation should be the same, but some differences were observed. These differences between tube housing temperatures observed for continuous operation and those observed for intermittent operation were due to differences in the duty cycle ratings specified by the x-ray tube manufacturer for continuous and intermittent operation.