Investigation on endurance evaluation of a portal crane: experimental, theoretical and finite element analysis

In this study, the stress on portal crane components at various payloads has been investigated theoretically, numerically and experimentally. The portal crane was computer-aided modeled and finite element analyses were performed so that the most stressed points at the each trolley position investigated on the main girder could be determined. In addition, the critical points were marked on the portal crane, and strain gages were attached to the those critical points so that stress values could be experimentally determined. The safety factor values at different payloads were determined by using finite element simulation. Results indicate that the most stressed component in the examined portal crane is the main girder. Experimental results indicate that the maximum stress value on the main girder is 3.05 times greater than the support legs and 8.99 times larger than the rail.

Performance Analysis of Gudgeon Pin of Various Cross Sections by FEM

Gudgeon pin are one of most heavily stressed component present in engine Gudgeon pin is used in automobile engines to connect piston and connecting rod. and its failure can cause seizure of the engine. Thus they are carefully designed. This project deals with gudgeon pin of different inner profiles keeping the outer diameter constant which is equal to piston boss to provide a more strengthen gudgeon pin. Profiles investigated are hollow, uniform stepped, tapered, step taper. The models with mentioned inner profiles keeping outer profile straight are made using CATIA and then analyzed for using ANSYS for parameters maximum principal stress, equivalent (von-mises) stress, strain energy and total deflection. Considering all these parameters most suitable design of gudgeon pin is decided. On investigation of the different profile it was found that step taper profile gave the best results .Thus providing a stronger gudgeon pin leading to decrease in chances of failure.

Composite Peening - A Novel Processing Technology for Graded Reinforced Aluminium Matrix Composites

Recently, the attention paid to Metal Matrix Composites (MMCs) has increased markedly. In particular, particle-reinforced MMCs are outstanding due to superior specific properties and their wear resistance. In order to further improve material utilization, recent investigations with local reinforcements in highly stressed component sections, the so-called Functionally Graded Metal Matrix Composites (FGMMC), are concerned. The production of such FGMMC was realized with composite peening - a modified process on the basis of micro shot peening. Due to this solid-phase process, ceramic particles can be introduced into regions close to the boundary layer. As preliminary studies on tin show, ceramic particles can be introduced close to the specimen surface even at room temperature. By varying process parameters, in particular by increasing the temperature, the penetration depth of the particles can be significantly increased. In case of aluminium as base material, an input of particles into the surface could be observed at a process temperature of 150 °C. The combination of aluminium with reinforced ceramic particles makes this process interesting for lightweight, wear-resistant and cyclically highly stressed structural components. Using composite peening to produce FGMMCs is a novel, economic approach.

Identification of Damage in Composite Structures Using Thermoelastic Stress Analysis

The application of a cyclic load on a composite material containing damage has the effect of heating due to the material viscoelasticity. This is exaggerated in the proximity of interlaminar failure because of friction between plies. Quantitatively studying a stressed component subject to these conditions using Thermoelastic Stress Analysis (TSA) has been inaccurate, as the localised heating has an effect on the thermoelastic response. Hence the thermoelastic signal from damaging composites will contain a stress-induced component and a temperature-induced component. In this paper a process is described that allows the thermoelastic signal to be de-coupled into a stress component and a temperature component. This is achieved using a combination of infra-red thermography and TSA. The process is based on the use of a special calibration device. The paper provides an experimental verification of the de-coupling using actual damaged composite components.