I am working on a project for a company to analyse the fatigue life of a component. There is an existing component that the company manufactures and the component fails by fatigue on the average 540 days. The component is a tube made of low carbon steel of yield 260N/sqmm and ultimate of 340N/sqmm. But the company gives a guarantee of 700 days to the customers. How can i simulate by theory the fatigue life of 540 days for that component.