Study on Stress Analysis of Araldite HY-951 and CY-230 Bell Crank Lever using Photoelasticity and FEM

Abstract

Bell crank lever is a bar capable of turning about a fixed point, used as a machine to lift the load by the application of small effort. Bell crank lever is used in railway signaling, governers of hartnell type, the drive for the air pump of condensers etc. The major stresses induced in the bell crank lever at the fulcrum are bending stress and fulcrum pin is shear stress. The maximum stresses are developed at the fulcrum. The Bell crank is a type of crank that changes motion through an angle. The angle can be any angle from 0 to 360 degrees, but 90 degrees and 180 degrees are most common. Hence, the work deals with the stress analysis of bell crank lever within the angle ranges 90⁰ to 180⁰ by finite element method using ANSYS WORKBENCH 14.5 software and Photoelasticity. Experimental and Analytical results are observed and compared, so that the obtained results are in close agreement with each other. For the photoelastic stress analysis which is the Experimental method, the bell crank lever models are prepared with photoelastic sheet of Araldite hardener HY-951 and curing agent CY-230 is used.

Keywords: Bell Crank Lever, Stress Analysis, MATLAB