该标准包括钻头设计参数、可接受的钻头材料、安全带要求和双边缘阶梯钻头的相关术语。参见NAS907，了解基本钻头结构、术语、点几何形状、柄配置、建议的应用领域，以及定义相关术语的术语表。目的本文件为航空航天行业提供了采购高速钢和钴双余量阶梯钻的统一标准。按照推荐的应用使用指定的钻头将确保以最佳质量、可靠性和经济性执行钻井任务。

Included in the standard are drill design parameters, acceptable drill materials, harness requirements and pertinenet nomenclature for double margin step drills. See NAS907 for basic drill construction, nomenclature, point geometries, shank configurations, suggested areas of application, and a glossary of terms defining relative terminology.PurposeThis document provides the aerospace industry with the uniform standard for the procurement of high-speed steel and cobalt double margin step drills. Use of the specifid drills in accordance with recommended applications will ensure the performance of drilling tasks with optimum quality, reliability, and economy.