API Spec 6A has been revised and enlarged considerably in its fifteenth edition published in 1986. Strict technical regulation and rigid quality control in manufacturing are taken into consideration in the new edition.

• 美国石油学会1986年出版的API Spec 6A《井口及采油树装置规范》第15版,与第14版比较,作了较大的修改和增补,对产品的制造提出了严格的技术与质量控制要求。