Experimental Investigation of the Performance of a Laboratory Screw Jack

Abstract

The purpose of this project was to carry out an experimental investigation on the performance of a laboratory screw jack in order to ascertain the force ratio (Mechanical Advantage), Velocity Ratio and Mechanical Efficiency of the machines at different loads. The experiment was done at different loads of; 450N, 400N, 350N, 300N, 250N, 200N, 150N, 100N and the Mechanical Advantage, Velocity Ratio and Mechanical Efficiency were calculated for true and approximate values and graphical relationships were established between efficiency and load, effort and load, effort against load using micro soft excel. It was established that, the machine was most efficiency of a screw jack is always less than 50% since the Mechanical Advantage and Velocity Ratio is less than half. The investigation also revealed that the efficiency not being constant was as a result of the different loading conditions the machine must overcome which include great frictional forces between the screw and the threaded base within which it forms. Keyboards: Laboratory, screw jack, experimental investigation, performance.