GDSE-05

GDSE-05

FLEXURAL AND TORSIONAL STRESS TEST UNIT

This newly conceived educational equipment is designed to fill a lack in the field of technical education connected to experimental mechanics and construction techniques. In fact, it permits to perform experimental control direct over movements occurred as consequence of stressing loads and deformations, in the most typical loading assumptions for flexural and torsional stressing. It is thereby made possible to perform experimentally, with outmost educational efficiency, the control of formulas derived from the elasticity theory as well as their practical use in a great variety of technological applications. A novelty in this system is represented by the control possibilities over deformations by use of electrical strain-gauges. This represents a further element of educational importance since permitting that students be illustrated with the characteristics and operation of these transducer which have now become of current use in practical engineering tasks, even outside of research laboratories.

The complete apparatuses of the unit are contained in a box-shaped container that may be parted into three sub-assemblies, and includes: 1. Metal bars for experimental testing. These have different shapes, mechanical properties and dimensions. Strain gauges are already bonded on them.

2. Arrangement of bars and relevant supports suitable for reproducing different constrain conditions and load applications.

3. Different weight masses suitable for providing flexural and torsional stressing.

4. Mechanical comparator and electronic measurement control board.

I - 16153 P.D. da Bissone 36r. GENOA - ITALY - Tel.: +39 010 6501969 Fax: +39 010 6501969 e-mail: patrone@ giacomopatrone.com http://www.giacomopatrone.com

GDSE-05

A part of the box container with test bar supports secured on it serves as load surface area. This plane surface is provided with rows of holes differently positioned and for the purpose of producing a variation in the span between the supports and, consequently, of the stresses in the bar. Moreover, a differentiation of these stresses may be achieved by varying the number and the magnitude of the loads applied on the end points of the test bar. A comparator is fixed on this same surface area by means of magnetic supports. It allows to determine deflections in several points on the bar under test. Ultimately, each test bar is fitted with four electric strain-gauges which are connected with the measurement control board on which the values of deformations produced on the test bars can be read out directly in micro inches/inches. The measurement control board of totally solid construction incorporating silicon planar integrated circuitry offers a very high degree of reliability under all operating conditions.

A detailed specification covering possible practical tests is supplied together with the equipment.

Moreover, a comprehensive description of the characteristics and tips for use of strain-gauges is also furnished.

TYPICAL TESTS POSSIBLE BY USE OF UNIT TYPE G.D.S.E./05 This unit permits to execute flexural and torsional tests on bars consisting of different materials (ferrous, non-ferrous alloys, plastics, resilient materials, concrete agglomerates, etc.) which may have different shapes and mechanical properties.

The involved tests may have comparative scope when theoretical results obtained by calculations are compared against result data obtained by use of mechanical equipment (weights and comparators) and data supplied by electronic equipment (strain-gauges and relevant measurement control board). Further to theoretical and practical experimentation of construction techniques, this unit makes it possible to gain knowledge of strain-gauge measuring methods, which involve: the selection of the appropriate type of strain-gauge, its bonding technique on the measure point, the measuring system to be adopted, the evaluation of the results obtained and the conversion of these data into judgement terms of the mechanical properties of materials under test. As it is possible to understand, these short technical notes illustrate quite modern techniques which, at present, are employed in different branches of practical and industrial applied research.

Operators specialising this particular field are much appreciated everywhere.

I - 16153 P.D. da Bissone 36r. GENOA - ITALY - Tel.: +39 010 6501969 Fax: +39 010 6501969 e-mail: patrone@ giacomopatrone.com http://www.giacomopatrone.com