A STUDY ON RELIABILITY, VALIDATION OF BATH TUB CURVE AND CONCEPT OF MADHAB’S HAT CURVE OF RELIABILITY

Abstract

“Zero defect” – one of the basic demands of the current generation. Everybody wants a defect free and reliable product. On the other hand this is a big challenge for the manufacturers to fulfill the demand of the customers. But to survive in this competitive globalization era an industry has to be excellent in all the aspects to make a qualitative product with a cost effective manner. To maintain high Reliability and least failures of equipments is a good example of Global Manufacturing Practice. Equally it is the biggest challenge for the engineers/managers to maintain a culture of “zero defect” and 100% reliability of the equipments in any Industry. The first step to achieve the target is to understand the basic concept of reliability, then to analyze and find a way. The reliability engineers are working day and night to improve the way forward. This study is a small step towards a big mission of “Zero Defect” the way the world is moving on. In this thesis a set of industrial fans used in a particular cement plant has been considered for the reliability study. As we know industrial process fans used in different industries like cement plants, steel plants, sponge iron plants, refractory plants etc are considered as important equipments. Any failure or down time associated with the process fans leads to the plant stoppage and production loss. In addition to this the maintenance cost also increases. So it is important to analyze the situation and actions should be taken to prevent the unwanted failures of the equipments in turn improve the reliability. In the first phase of the study, the Validity of Bath Tub Curve has been checked by the help of failure data analysis. In the second phase of the study, the concept of Hat curve of Reliability has been established by the help of MINITAB software, using the equipment failure data and reliability analysis. This would be known as Madhab’s Hat Curve of Reliability. In the third phase of the study various methods of reliability improvement has been discussed briefly.