Foreword

DL/T 5210 Code for Construction Quality Acceptance and Evaluation of Electric Power Construction includes the following 8 parts：

DL/T 5210.1　Part 1：Civil Work

DL/T 5210.2　Part 2：Boiler Unit

DL/T 5210.3　Part 3：Steam Turbine Generator Units

DL/T 5210.4　Part 4：Instrumentation and Control

DL/T 5210.5　Part 5：Piping & System

DL/T 5210.6　Part 6：Water Treatment & Hydrogen Generation Equipment and System

DL/T 5210.7　Part 7：Welding

DL/T 5210.8　Part 8：Processing Preparation

This Part is the 5th part of DL/T 5210.

This Part is prepared in accordance with the document-Notification on Issuing 2008 Industry Standard Project Plan（NDRC-Industry〔2008〕No.1242）issued by National Development and Reform Commission.

The contents of Thermal Power Construction Quality Inspection and Evaluation Standard-Piping Section（2000 Edition，National Power Supply〔2001〕No.116）issued by the fomer State Electricity Corporation of China is referenced by this Part during the drafting.

Annex A is normative annex in this Part.

This Part was proposed by China Electricity Council.

This Part isinterpreted by Thermal Power Construction Standardization Technical Committee of Power Trade.

The chief written corporations of this Part is Hunan Provincial Thermal Power Construction Corporation.

The participants for writing this Part are Tianjin Electric Power Construction Company，Jiangsu Electric Power Construction No.3 Engineering Company，Chongqing Power Construction Company and Hunan Provincial Power Trade Association.

The main drafters of this Part are Li Weiguo，Chen Jinong，Zhou WenJiang，Li Pengqing，Zhou Defu，Yang Jianhua，Yang Fengzhen，Cai Kehong，Zhao Changhe and Xue Zhijiang.

Translators of this Part in English version are Kang Yujun，Xiao Guohua，Yu Cheng，Tian Xiaoxuan，Li Yimin and Cao Haitao of Xi'an Thermal Power Research Institute Co.，Ltd（TPRI for short）.

Reviewers of this Part in English version are Liang Changqian，Bi Jun，Mi Haolin，Jing Xiaohua and Liang Jun.

Thermal Power Construction Quality Inspection and Evaluation Standard-Piping Section（2000 Edition，National Power Supply〔2001〕No.116）issued by the former State Electricity Corporation of China shall be obsoleted since the date of implementation of this Part.

Any comments and suggestions during the execution of this Partis are welcomed to feed back to the Standardization Center of China Electricity Council（Address：No.1，Lane 2，Baiguang Road，Beijing；Postcode：100761）.