A sturdy base contains all parts of the Diaphragm apparatus. This forms a compactproduct, ideal for use on a workbench. Two heavy flanges clamp the edge of the diaphragm to provide built-in edge conditions. The area directly under the diaphragm contains oil. The Diaphragm apparatus allows students to examine the effectof pressure on the surface profile of a diaphragm. The signals from eachstrain gauge are shown on a digital display. A digital dial gauge is fitted toa digital position indicator. The dial gauge can be traversed across thediaphragm to measure its surface profile. They can also determine thedistribution of circumferential and radial strains across its diameter. Eight strain gauges are cemented to the top surface ofthe diaphragm in various positions and at different radii. Each strain gaugecircuit is a full bridge, with high-stability resistors. Students use a hydraulic pump to increasethe oil pressure under the diaphragm. They record the strain readings and diaphragm profile at different pressures. Both instruments can connect to optionalVersatile Data Acquisition System.
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Sturdy, compact, self contained bench top unit for determining the surface strains and deflections of a flexible diaphragm under varying pressures. Round Diaphragm Apparatus the diaphragm is flexed, the strain gauge output is fed into a digital display, which is supplied. An aluminium diaphragm is clamped rigidly around its outer edge, creating a volume underneath its surface into which oil is filled. On the top surface of the diaphragm are attached 8 precision strain gauges at differing orientations.
An analogue pressure indicator monitors the pressure, whilst an electronic pressure sensor monitors the same pressure but gives an output signal to the digital display. The force applied to the diaphragm is created by pressurising the oil underneath the diaphragm using a fine adjustment control mechanism.
Experimental Capabilities:
Measurement of diaphragm disc surface strain using strain gauges
Determination of circumferential strain
Diaphragm surface profile
Measurement of diaphragm disc deflection with a dial gauge
Determination of radial strain
Comparison of actual and theoretical results
Mohr Circl
Strain gauge technology and uses.
