Foreword

According to the requirements specified in the Plan for Developing Professional Standards in 2004（Document Number：〔2004〕No.872）issued by the General Administration Office of National Development and Reform Commission，this specification is revised by its development team based on wide and intensive investigations and studies made，practices summarized，comments requested as well as references to international codes and advanced foreign standards.

This specification comprises 4 chapters.

The main technical contents of this Specification include series of seamless and welded carbon steel and alloy steel pipe size.

This specification is revised on a basis of Series of Steel Pipe Size in Petrochemical Industry（SH 3405-1996），and main revisions include：

—Enlarge the range of nominal diameters from DN 15-DN 2000 to DN 6-DN 3400；

—Add series DN 6，DN 8，DN 90，DN 1050，DN 1150；

—Outside diameters of steel pipes are consistent with ASME B36.10M and ASME B36.19M without rounding；

—Update the normative references，and cancel two reference standards：GB 5681 and SY/T 5297；

China Petrochemical Corporation（Sinopec Group）is in charge of the administration of this specification，Sinopec Technical Center for Piping Design and Engineering is responsible for its routine management，and Sinopec Luoyang Petrochemical Engineering Corporation is tasked for explanation of specific technical contents.If any comments and recommendations are proposed in implementation of this specification，please send your comments/recommendations to the routine maintenance organization and chief development organization.

Routine management organization：

　　　　　　　Sinopec Technical Center for Piping Design and Engineering

　　　　　　　Address：Bldg.21 Anyuan，Anhui Bei Li，Chaoyang District，Beijing

　　　　　　　Postcode：100101

　　　　　　　Tel：010-84877282

　　　　　　　Fax：010-64949514

Chief development organization：

　　　　　　　Sinopec Luoyang Petrochemical Engineering Corporation

　　　　　　　Address：No.27，West Zhongzhou Rd.，Luoyang，Henan Province

　　　　　　　Postcode：471003

Chief drafting staff：

　　　　　　　Wang Jinfu　Yang Ruiping

Chief reviewing staff：

　　　　　　　Wang Jianyu　Ge Chunyu　Zhang Dejiang　Zhang Fayou　Li Yonghong

　　　　　　　Lei Yunzhou　Yang Pinghui　Yuan Can　Li Xiuming　Zhang Baojiang

　　　　　　　Chen Yongliang　Xu Dan　Jiang Guoxian　Xu Mingcai

　　　　　　　Wang Changsheng　Dong Xiufeng

This specification was initially issued in 1989，and first revised in 1996.This edition is the 2nd revision.