本标准描述了测量和计算程序，用于确定具有光滑外表面和浮动或固定屋顶的直立焊接（搭接/对接）圆柱形储罐或立式圆柱形储罐的直径。光学基准线法是确定储罐直径的手动储罐捆扎法的替代方法。第2.2B章应与API标准2.2A结合使用。

This standard describes measurement and calculation procedures for determining the diameters of upright welded (lap/butt) cylindrical tanks, or vertical cylindrical tanks, with a smooth outside surface and either floating or fixed roofs. The optical reference line method is an alternative to the manual tank strapping method for determining tank diameter. Chapter 2.2B should be used in conjunction with API Standard 2.2A.