22-10-2014, 09:28 AM
Abstracts: Foundry industry suffers from poor quality and productivity due to the large number of process-parameters, combined with lower penetration of manufacturing automation and shortage of skilled workers compared to other industries. Nowadays buyers demand defect-free castings and strict delivery schedule, which foundries are finding it very difficult to meet. The defects need to be diagnosed correctly for appropriate remedial measures; otherwise new defects may be introduced. Unfortunately, this is not an easy task, since casting process involves complex interactions among various parameter sand operations related to metal composition, methods design, molding, melting, pouring, shake-out, fettling and machining. At times, instead of applying complicated techniques, basic fundamentals help solve involved foundry problems. For example, if shrinkage porosity is identified as gas porosity, and the pouring temperature is lowered to reduce the same, it may lead to another defect, namely cold shut. In this work approach is presented to casting defect identification, analysis and rectification. The defects are classified in terms of their appearance, size, location, consistency, discovery stage and inspection method. This helps in correct identification of the defects. For defect analysis, the possible causes are grouped into design, material and process parameters. Based on the results and their interpretation, the optimal values of the parameters are determined to eliminate the defects. The proposed two approaches overcomes the difficulty of controlling process parameters in foundries with manual processes and unskilled labor, by making the design more robust (less sensitive) with respect to process parameters. This will especially help foundries to significantly improve their quality levels. In second approach from this work the modeling can be done by using simulation software which will give very much near results to actual process.