钻井和修井结构的操作@检查@维护@和维修（第四版；ERTA：2013 年 9 月

This document provides guidelines and establishes recommended procedures for inspection, maintenance, and repair of items for drilling and well servicing structures to maintain the serviceability of this equipment. These recommendations should be considered as supplemental to, and not as a substitute for, the manufacturer’s instructions and the recommendations in API 54. Items of drilling and well servicing structures covered are masts/derricks, substructures, and their accessories.