EXPERIMENTAL INVESTIGATION OF THE CONTACT HEAT RESISTANCE IN THE THREADED JOINT ZONE OF CONTACT SURFACES

For the fi rst time the range of values has been determined experimentally of the absolute contact heat resistance in the zone of the threaded joint of two parts of cylindrical form from aluminum alloy with a thread length exceeding its diameter by a factor of more than 3 with the transferred heat fl ux varied over the range from 4.5 to 78.5 W. It has been shown that the contact heat resistance is infl uenced by the value of the transferred heat fl ux, the presence of a heat conducting medium in the contact zone, and the conditions of tightening the thread for contact heat resistance. It has been established that in a threaded joint of length 53 mm having a diameter of 14 mm and a thread pitch of 0.5 mm without using a heat conducting medium in the contact zone, as the heat fl ux increases from 4.5 to 78.5 W, the value of the contact heat resistance without tightening of the thread decreases from 0.35 to 0.18^o C/W. Tightening of the thread up to the stop leads to an insignifi cant decrease in the value of the contact heat resistance. At the same time the injection into the contact zone of the threaded joint of the heat conducting paste KPT-8 decreases the heat resistance of the contact by a factor of 2.2 at the minimal transferred heat fl ux (4.5 W) and by a factor of 1.6 at the maximal heat fl ux (78.5 W).
   
Author:  Yu. E. Nikolaenko and A. S. Postol
Keywords:  contact heat exchange, heat resistance, threaded joint, heat pipe, light emitting module.
Page:  1097