Journal of Information Engineering and Applications www.iiste.org ISSN 2224-5782 (print) ISSN 2225-0506 (online) Vol.6, No.3, 2016 10 Study on Stress Analysis of Araldite HY-951 and CY-230 Bell Crank Lever using Photoelasticity and FEM Prasanth Kumar Mallipudi L.Dinesh Anil Neerukonda Institute of Technology and Sciences, Sangivalasa, Visakhapatnam-531162 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 90 0 to 180 0 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 1. Introduction Stress analysis is an engineering discipline covering methods to determine the stresses in materials and structures subjected to forces or loads. Stress analysis is a primary task for civil, mechanical and aerospace engineers involved in the design of structures of all sizes, such as tunnels, bridges and dams, aircraft and rocket bodies, mechanical parts, and even plastic cutlery and staples. Stress analysis is also used in the maintenance of such structures, and to investigate the causes of structural failures. The present work deals with the stress analysis of bell crank lever within the angle ranges 90 0 to 180 0 by finite element method using ANSYS WORKBENCH 14.5 software and Photoelalstic Stress Analysis. Experimental and Analytical results are observed and compared, so that the obtained results are in close agreement with each other. 2. Experimental Stress Analysis Bell crank lever is used to lift a load by the application of a small effort. For the analysis of bell crank lever the most critical area is considered and according to that the two dimensional model of bell crank lever is prepared. The different shapes of the bell crank lever are shown in the below figures. Three different loads, 100N, 150N, 200N were applied at one end and then the stresses calculated. Figure 1 Bell Crank Lever with 90 0