Flanges are used when the piping joint needs dismantling. These are used mainly at equipment’s, valves and specialties. In certain pipelines where maintenance is a regular feature, breakout flanges are provided at definite intervals. A flanged joint is composed of three separate and independent although interrelated components; the flanges, the gaskets and the bolting. Special controls are required in the selection and application of all these elements to attain a leak-proof joint.