本标准建立了MJB螺纹形状的基本三角形轮廓、设计轮廓、标准螺距、公差等级、公差和尺寸公式、公差表和命名系统。由于支墩螺纹的特殊应用，本标准未确定首选直径节距系列，每次应用都需要使用本文给出的螺纹尺寸公式和相关公差，以得出螺纹尺寸要求。

This standard establishes the basic triangular profile for the MJB thread form, the design profiles, standard pitches, tolerance classes, formulae for tolerances and dimensions, tolerance tables, and a system of designations. Because of the specialized application for buttress threads, no preferred diameter-pitch series have been established for this standard and each application will require use of the thread formulae for dimensions and related tolerances given herein for deriving the thread dimensional requirements.