Internal Elastic Forces Apparatus

Features Low cost effective teaching Self-contained Wall-mounted Simulates strains for a bolt stressing a tube Determination of stiffness of tension and compression springs 3 year warranty Range of Experiments To determine the stiffness of springs in tension and compression To investigate a self-straining system similar to a bolt in a tube. In particular to measure the reduction in length of the "tube", and the forces in the springs To measure the increase in length and forces in the system due to applying an external tensile load Description The apparatus is a self straining system analogous to a bolt stressing a tube, enabling the final overall deflection of the system to be determined. It consists of a frame in which there are two springs. A tension spring with means of adjusting its length has a disc at its lower end. Between this disc and the top of the frame is fitted a compression spring. A weight hanger attached to the disc enables the two springs to be loaded. The stiffness of the two springs is different so that an overall deflection is induced. The two springs can be installed separately in the frame so that the stiffness of each can be determined. In the case of the compression spring, it is necessary to apply loads through a cord and pulley arrangement. A graduated scale alongside the disc shows the deflection of the spring(s). Excellent results are achieved due to the low friction of the equipment. This equipment is part of a range designed to both demonstrate and experimentally confirm basic engineering principles. Great care has been given to each item so as to provide wide experimental scope without unduly complicating or compromising the design. Each piece of apparatus is self-contained and compact. Setting up time is minimal, and all measurements are made with the simplest possible instrumentation, so that the student involvement is purely with the engineering principles being taught. A complete instruction manual is provided describing the apparatus, its application, experimental procedure and typical test results.