API SPEC 6A-2018 Specification for Wellhead and Tree Equipment (TWENTY-FIRST EDITION; API Monogram p API Spec 15PX-2018 交联聚乙烯（PEX）管线管规范 API SPEC 5L-2018 Line Pipe (FORTY-SIXTH EDITION; ERTA 1_ MAY 2018; Effective November 1, 2018) API Spec 6D-2022 阀门规范 Specification for Valves API SPEC 19OH-2018 Openhole Isolation Equipment (First Edition) API SPEC 17L1-2021 Specification for Ancillary Equipment for Flexible Pipes and Subsea Umbilicals - API RP 5C6-2018 Pipe with Welded Connectors (THIRD EDITION) API TR 979-2018 Applications of Refractory Lining Materials (FIRST EDITION)