THE CONSTRUCTION DETAILS OF AN AUTOMATIC RECORDING TEMPERATURE CONTROLLED TORSION MACHINE
GLENN L MARTIN COLL OF ENGINEERING AND AERONAUTICAL SCIENCES COLLEGE PARK MD
Pagination or Media Count:
The device automatically plots torque-twist curves during the course of a test and shuts off when the total angular displacement reaches 720. Any rate of strain from 360hr to 180min may be obtained and held constant within 1. The torque is measured by the expansion of a ring dynamometer coupled to an adjustable lever at right angles to the axis of rotation of the bar. An electrical signal corresponding to the expansion of the dynamometer is fed to the Y-arm of an X-Y recorder Leeds Northrup modified Series 600 Speedomax. A signal obtained from a voltage-dividing potentiometer connected to an angular extensometer is connected to the X-arm of the recorder. The apparatus includes a temperature control which is actuated by temperature changes of or -0.25 C. The sensing element is a 25-ohm platinum resistance thermometer. The arrangement by which liquid nitrogen is introduced into the cooling container, the pumping method, and the reservoir and reservoir control are described.
- Test Facilities, Equipment and Methods