Standard No.:	GB/T 16702.7-2025
English Name:	Design specification for mechanical components in nuclear island of pressurized water reactor nuclear power plants―Part 7：Supports
Chinese Name:	压水堆核电厂核岛机械设备设计规范第7部分：设备支承
Chinese Classification:	F69    Nuclear reactor and nuclear island equipment of nuclear power plant
Professional Classification:	GB    National Standard
ICS Classification:	27.120.20 27.120.20    Nuclear power plants. Safety 27.120.20
Source Content Issued by:	SAMR; SAC
Issued on:	2025-02-28
Implemented on:	2025-2-28
Status:	valid
Superseding:	GB/T 16702-2019 Design code for mechanical components in nuclear island of pressurized water reactor nuclear power plants
Target Language:	English
File Format:	PDF
Word Count:	31000 words
Translation Price(USD):	930.0
Delivery:	via email in 1~5 business day

GB/T 16702.7-2025 Design specification for mechanical components in nuclear island of pressurized water reactor nuclear power plants―Part 7：Supports English, Anglais, Englisch, Inglés, えいご This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered. ICS 27.120.20 CCS F 69 National Standard of the People's Republic of China GB/T 16702.7-2025 Partly replaces GB/T 16702-2019 Design specification for mechanical components in nuclear island of pressurized water reactor nuclear power plants - Part 7: Supports 压水堆核电厂核岛机械设备设计规范 第7部分：设备支承 (English Translation) Issue date: 2025⁃02⁃28 Implementation date: 2025⁃02⁃28 Issued by the State Administration for Market Regulation the Standardization Administration of the People's Republic of China Contents Foreword Introduction 1 Scope 2 Normative references 3 Terms and definitions 4 Overall requirements 5 Material 6 Design 7 Manufacturing and inspection 8 Standard support and standard support component Design specification for mechanical components in nuclear island of pressurized water reactor nuclear power plants - Part 7 : Supports 1 Scope This document specifies the requirements for materials, design, manufacture, inspection and standard support parts for equipment support in nuclear island machinery of PWR nuclear power plants. This document is applicable to equipment support and its parts specified in GB/T 16702.1-2025. 2 Normative references The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB 3098 Mechanical properties of fasteners GB/T 5313 Steel plate with through-thickness properties GB/T 16702.1-2025 Design specification for mechanical components in nuclear island of pressurized water reactor nuclear power plants - Part 1: General principle GB/T 16702.2-2025 Design specification for mechanical components in nuclear island of pressurized water reactor nuclear power plants - Part 2: Class 1 components GB/T 16702.3-2025 Design specification for mechanical components in nuclear island of pressurized water reactor nuclear power plants - Part 3: Class 2 components GB/T 16702.4-2025 Design specification for mechanical components in nuclear island of pressurized water reactor nuclear power plants - Part 4: Class 3 components GB/T 16702.5 Design specification for mechanical components in nuclear island of pressurized water reactor nuclear power plants - Part 5: Small components GB/T 19804 Welding - General tolerances for welded constructions - Dimensions for lengths and angles - Shape and position NB/T 20001 Fabrication rules for mechanical components of PWR nuclear island NB/T 20002 (all parts) Welding rules for mechanical components of PWR nuclear islands NB/T 20002.6 Welding rules for mechanical components of PWR nuclear islands - Part 6: Production welds 3 Terms and definitions The terms and definitions defined in GB/T 16702.1-2025 and the following are applicable to this document. 3.1 supports structural elements that bear equipment loads and transfer them to buildings or building structure metal frames 3.2 members of supports components of supports that bear loads and ensure geometric shape stability 4 Overall requirements 4.1 General rules The relevant requirements of NB/T 20191 shall be taken into account during the design of equipment supports. The jurisdictional boundaries of this document do not include the following aspects: a) The metal frame mentioned in 3.1 that forms part of the building structure, and the intermediate components in the load transfer path specified in 4.2. 2, such as electric motors, valve operating mechanisms, channel structures, etc.; Note: The metal frame design needs to leave an adjustment amount at least equal to the civil tolerance for installation and adjustment. b) a supporting member whose sole function is to transmit dynamic loads due to impaired integrity of the pressure boundary; c) Quality degradation caused by factors such as corrosion, erosion, irradiation effects or material instability during service. However, under normal operating conditions, this quality degradation is expected (for example, damage to composite materials due to irradiation effects). Therefore, the minimum service life of support integrity should be specified in the equipment specification. The rules of this document apply to members that transmit upward loads so that the support is in tension, members that transmit downward loads so that the support is in compression and all devices designed to ensure structural stability, such as spring-fixed rocking supports and vibration isolators, etc. The rules of this document do not apply to the mechanical or hydraulic systems that play the role of vibration damping or dynamic restraint in the above components, but only to the connections from the system to the equipment and to the building structure. Figure1is a schematic diagram of the boundary demarcation between civil structures, supports under the jurisdiction of this document, and equipment. 4.2 Applicable boundaries 4.2.1 Demarcation of boundaries between supported equipment and support members 4.2.1.1 Demarcation of boundaries between equipment and integral support The integral support and the scope of application of this document are as follows. a) an integral support comprising: ——Integral connectors cast or forged with the equipment; ——Supports or supporting connectors welded to the equipment; ——Integral supports welded to integral connections cast or forged with the equipment. b) In this case, the scope of application of this document is as follows. ——Equipment, according to its grade, should comply with the provisions of GB/T 16702.2-2025, GB/T 16702.3-2025, GB/T 16702.4-2025 and GB/T 16702.5 respectively. ——Integral connectors cast or forged with the equipment shall comply with the relevant provisions of the equipment [see Figure 2a)]. ——Supports or supporting connectors welded to the equipment should comply with the provisions of this document. At this time, the application scope of this document is divided into the boundary line is located on the weld joining the equipment to the integral support. The connection weld itself, in accordance with the provisions of 5.2. 2.2 in GB/T 16702.1-2025, shall comply with the relevant provisions of the equipment [see Figure 2b) and c)]. In addition, supports or connectors welded to the equipment can also be treated as parts or components of the equipment. ——The integral support part welded to the integral connector cast or forged with the equipment shall comply with the provisions of this document. In this case, the dividing line of the application scope of this document is located on the weld joint between the integral connector and the support part. When the weld position. When the width on both sides of the equipment is beyond 2t (t is the minimum allowable wall thickness of the equipment at the connection point), the weld shall comply with the provisions of this document [see Figure 3a]; Otherwise, the weld should comply with the rules of the equipment. Unless it can be proved, this connection area will not have a substantial impact on the mechanical properties of the equipment.