定义顶点线程；直径为3/16英寸至5英寸的标准系列单螺纹的基本尺寸、极限和公差表。同意ASA B1。5:1952，直径为3/8英寸、7/16英寸、1英寸、1 3/16英寸和1½英寸的螺距除外。2G、3G和4G符合美国标准，以及更高级的5G。提供了扩展直径/节距组合范围的有效直径公差表。根据这些和相关表格，可以计算出单头或多头梯形螺纹的任何特殊直径/节距组合的极限尺寸。交叉参考:BS 350BS 2517

Defines Acme thread; tables of basic sizes, limits and tolerances for standard series of single start threads 3/16 in to 5 in diameter. Agrees with ASA B1.5:1952 except for pitches associated with diameters 3/8 in, 7/16 in, 1 in, 1 3/16 in and 1½ in. 2G, 3G and 4G fits in the American standard included, together with finer class, 5G. Tables of effective diameter tolerances for extended range of diameter/pitch combinations are provided. From these and related tables limiting dimensions for any special diameter/pitch combination for single or multi-start Acme thread can be calculated.Cross References:BS 350BS 2517