Carbon steel flange standards and requirements

Carbon steel flange in accordance with national standards require the size, tolerance range and other production of the flange, the difference between the flange is not produced according to standard sizes also known as the second standard flange (some people call non-standard flange is incorrect), usually some unscrupulous businessmen will reduce the thickness of the flange, the outer diameter of the two dimensions to achieve the purpose of saving materials, and the use of scrap steel or steel processing flange of the edge material.

Usually this steel is the chemical composition and mechanical properties do not meet the standards of the waste, and even more black steel mills with private steel production flange, this private steelmaking using steelmaking technology is obsolete and can not guarantee the mechanical properties and welding performance, the use of the steel may not be able to weld with the steel pipe, or the steel itself has cracks, pores, etc. Welded on the leakage will also be. So buy flange try to use carbon steel flange.