GB/T 10868-2018Steam converting valves for power station (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009. This standard replaces GB/T 10868-2005 "Power Station Temperature Reducing Valve". Compared with GB/T 10868-2005, except for editorial changes The main technical changes are as follows:

--- Added terminology (see 3.4, 3.5, 3.6, 3.8, 3.14,

--- Increased the basic error, hysteresis, dead zone, and rated stroke deviation of performance requirements (see 5.3.1);

--- Modify the pressure characteristics and flow characteristics in the original performance requirements, unified change to linear (LN) and equal percentage (EP) flow rate Deviations from the characteristic curves and slope deviations from the inherent flow characteristics (see

5.3.3 and 5.3.5,

--- Increased physical and chemical requirements and regulations for Grade III forgings (see 5.5.5);

--- Increased the calculation of rated flow and leakage (see Appendix A). This standard is proposed and managed by the National Standardization Technical Committee for Boiler and Pressure Vessels (SAC/TC262). This standard was drafted by: Hangzhou Huahui Valve Co., Ltd., Shanghai Power Generation Equipment Design and Research Institute Co., Ltd., and Harbin Power Group. Harbin Power Station Valve Co., Ltd., Wuhan Boiler Group Valve Co., Ltd., Huaxia Valve Co., Ltd., Qingdao Power Station Valve Co., Ltd. Secretary, South Valve Manufacturing Co., Ltd., Zhejiang Longde Environmental Protection Thermoelectric Co., Ltd. The main drafters of this standard are Chen Lilong, Zhang Ming, Chen Xiubin, Chen Weiping, Song Huanqiao, Zhang Na, Chen Xuefeng, Liu Shizhong, Wei Yubin, and Chen Wenlong. The previous versions of the standard replaced by this standard are.

--- GB/T 10868-1989, GB/T 10868-2005. Power station temperature reducing and pressure reducing valve

1 Scope

GB/T 10868-2018 is the Chinese national standard on steam converting valves for power station, in the field of energy and heat transfer engineering. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 6 February 2018 by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China; Standardization Administration of China, and has been in force since 1 September 2018. Classification: ICS 27.060.30, CCS J98. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

This standard specifies the terminology and definition of power station temperature reducing and pressure reducing valve, ordering guide, technical requirements, materials, inspection and test, quality certificate, Marking, packaging, delivery and shipping. This standard applies to work pressure P <= 35MPa, working temperature t <= 625 °C power station steam system with temperature reducing valve. Working pressure P <= 35MPa, operating temperature t <= 625°C, power station steam system pressure reducing valve and power station with operating temperature t >625°C Steam system with temperature reducing valve can be implemented by reference.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article Pieces. For undated references, the latest version (including all amendments) applies to this document.

GB/T 1047 Definition and selection of DN (nominal size) of pipeline components

GB/T 1048 Definition and Selection of PN (Nominal Pressure) Pipeline Components

GB/T 9113 Integral Steel Pipe Flange

GB/T 12221 Metal Valve Structure Length

GB/T 12224 steel valve general requirements

GB/T 12229 General Valve Carbon Steel Casting Technical Conditions

GB/T 15056 Casting Surface Roughness Evaluation Method

GB/T 21465 valve terminology

GB/T 26480 valve inspection and test

JB/T 5223 Pneumatic Long Stroke Actuator for Industrial Process Control Systems

JB/T 5263 power station valve cast steel technical conditions

JB/T 6439 Valve Pressure Parts Magnetic Powder Inspection Inspection

JB/T 6440 Valves Pressed Castings Radiographic Inspection