浅谈新版RCC-M2007的变化

2007版的RCC-M标准是RCC-M(2000版)标准与2002、2005年补遗和2007年的修改结合而成的产物。本文介绍了RCC-M 2007版的更新原因,对引用标准的更新。结合欧盟承压设备指令(PED)和法国核能法令(ESPN)审查管理要求的改变、分级变化以及设备鉴定、材料、制造和焊接、无损检验等各卷章的变化介绍了RCC-M 2007版的更新项。     

核电厂用3级海水介质用不锈钢承压铸件标准对比研究

文章对比分析了NB/T 20007. 28-2014与RCC-M M3402 (2007版)、ASME SA-995 (2015版)海水介质中不锈钢承压铸件材料标准,研究了3个标准的异同,讨论了我国核电标准与国际主要标准之间的等效关系,以期为核电工程中选用我国核电标准提供支撑,促进我国核电标准的使用以及海外工程的应用。     

国产304NG控氮不锈钢应用性能研究

通过向奥氏体不锈钢中加入适量的氮和降低碳含量,可以提高钢的强度,改善钢的耐腐蚀性能,而基本上不影响钢的塑性和韧性.本文对核工程用304NG控氮不锈钢的应用性能进行了研究,包括材料的基本特性和应力腐蚀、均匀腐蚀等性能.结果表明,国产304NG控氮不锈钢的综合性能满足核工程需求,与国外同类产品处于同一水平.     

RCC-M 2007版的改进及对我国相关标准的影响

我国已建和在建的多座核电站采用的都是从法国引进的核电技术,这些工程所采用的设计和建造规范基本是法国的RCC系列标准.因此,RCC系列标准,尤其是RCC-M对我国核电行业将会有着长远而重要的影响.文章介绍了RCC-M最新版2007版的改进内容,并对这些改进进行了评述；同时对正在升版的我国国家标准GB/T 16702提出了升版建议.     

核电双相不锈钢S32101焊接工艺研究

双相不锈钢的金相组织是铁素体与奥氏体,具有碳钢和奥氏体不锈钢的综合性能,尤其是耐海水腐蚀性能优越,且采用Mn、N代镍,降低造价。由于不良的热成形性能,双相不锈钢在以往核电建设方面仅用于仪表小管。在AP1000核电中,S32101双相不锈钢大量用于结构模块,主要性能是结构强度(常温与高温)和耐腐蚀性。结构模块制造、安装过程中的焊接工艺是保证模块整体性能的特殊工艺。双相不锈钢S32101的焊条电弧焊,需要掌握不同焊接线能量对的熔敷金属性能的影响,得出最佳的焊接工艺规范。     

RCC-M标准2007版与2000版的差异分析

介绍了RCC-M 2007版在设备鉴定、材料、制造和焊接、无损检验等各卷章的变化介绍了更新项。并对其更新的原因及对国内设计者和制造商的影响进行了分析。针对国内引进法国EPR核电机组设计自主化和设备国产化,对国内设计院和设备制造厂提供借鉴。     

钛合金TA16弹塑性修正因子数值分析方法研究

本文对核级规范提供的奥氏体不锈钢材料的弹塑性修正因子（KE）的各种敏感因素进行数值验算,确定了不锈钢材料Z2CND18.12(控氮)简化弹塑性疲劳分析所需KE与规范限值之间最小保守裕量为12%。基于钛合金TA16的单轴拉伸、应变循环和应力循环试验,确立了TA16在30 ℃和350 ℃的Chaboche本构模型参数。基于TA16的本构模型参数,对TA16开展各种敏感因素下的弹塑性分析,并参考奥氏体不锈钢的KE表达式和Z2CND18.12(控氮)的KE最小保守裕量迭代计算出TA16的相关系数。TA16的相关系数A、B、C、m、n分别为1.37、1.26、1.37、2.0和0.25。     

核工业标准化研究所引进2007版RCC-M(英法文)和RCC-MR(英文)

法国AFCEN(核岛设备设计建造规则协会)机构最新发布了2007版RCC-M(压水堆核岛机械设备设计和建造规则)和RCC-MR(液态金属快中子增殖堆核岛机械设备设计和建造规则)两套法规标准.我单位及时与AFCEN取得联系,引进了这两套最新资料.     

核电厂核2级承压管道抗震设计规范对比分析

RCC-M、ASME(2007版)及GB 50267-97为目前核电厂设备、系统、部件设计所遵循的主要技术标准,3者对核电厂部件的分级基本相当,在核2级承压管道设计方面的规定内容相似但不完全相同.在地震输入方法上,GB 50267-97、ASME(2007版)及RCC-M基本相同,GB 50267-97中硬土场地的水平...     

钛合金TA16弹塑性修正因子数值分析方法研究

本文对核级规范提供的奥氏体不锈钢材料的弹塑性修正因子(KE)的各种敏感因素进行数值验算,确定了不锈钢材料Z2CND18.12(控氮)简化弹塑性疲劳分析所需KE与规范限值之间最小保守裕量为12%。基于钛合金TA16的单轴拉伸、应变循环和应力循环试验,确立了TA16在30℃和350℃的Chaboche本构模型参数。基于TA16的本构模型参数,对TA16开展各种敏感因素下的弹塑性分析,并参考奥氏体不锈钢的KE表达式和Z2CND18.12(控氮)的KE最小保守裕量迭代计算出TA16的相关系数。TA16的相关系数A、B、C、m、n分别为1.37、1.26、1.37、2.0和0.25。     

反应堆堆内构件仪表套管焊接变形的控制

针对核电厂反应堆堆内构件不锈钢仪表套管柱在自由状态下焊接时,较易出现焊接变形的不符合项,提出一系列包括优化焊接工艺和参数等的控制焊接变形措施。焊接后的液体渗透检验、射线照相检验及尺寸检查结果表明,按此改进工艺焊接的仪表套管柱无缺陷存在;焊接变形量大大减少,位置度、尺寸精度均符合设计要求。     

304奥氏体不锈钢在不同浓度硝酸中的电化学行为

采用动电位极化曲线测量、开路电位测量等技术,研究了304奥氏体不锈钢在不同浓度硝酸溶液中的电化学腐蚀行为,并对304奥氏体不锈钢在硝酸溶液中的电化学反应历程进行了探讨。结果表明：304奥氏体不锈钢在硝酸溶液中具备不锈钢典型的极化曲线特征,有多个钝化区和过钝化区;硝酸浓度升高促进不锈钢表面钝化膜的生成,使开路电位向正电位方向移动,降低了硝酸溶液对不锈钢的腐蚀倾向,同时,随着硝酸浓度的升高,不锈钢的点蚀电位升高,提高了不锈钢耐点蚀能力;在硝酸溶液中,不锈钢的腐蚀速率同时受到酸度和硝酸根浓度的影响,二者相互矛盾,导致硝酸浓度对腐蚀速率的影响呈不规律性。结果表明,在0.5 mol/L硝酸中,不锈钢的腐蚀速率最高。     

Fatigue strength of dissimilar welded joints for the main vessel of an LMFBR

The employment of welded joints composed of dissimilar metals is one simple and inexpensive way to connect a main vessel made of austenitic stainless steel and a roof slab constructed of ferritic steel in the design of liquid metal fast reactors. Since dissimilar-metal welded joints have not been used for such large structures so far in Japan, the structural integrity of this type of joint should be carefully examined for such a design option to be selected. Here various kinds of tests were conducted for eleven types of welded joints of 50 mm thickness to obtain this fundamental strength characteristics. Type 304 stainless steel was used as one of the parent metals in all the joints. They differ from each other in regard to the type of ferritic steel, welding metal and welding procedure. Low-cycle fatigue tests were conducted for round-bar specimens made from these welded joints at room temperature. Fatigue crack-propagation tests were also conducted for some of the joints. Tests after manufacturing a large-scale shell model were also conducted. The results of these tests demonstrated that the present manufacturing technique can, produce welded joints of high quality and reliability. A trial calculation for actual design conditions showed the existence of large margins against fatigue failure or fatigue crack-propagation of a significant amount.     

Welding of material grade TP 347 mod.

Niobium-stabilized austenitic materials have been successfully used in Germany for more than 25 years. They play an important role in German LWR technology. The main reason for the choice of these stabilized stainless steels is their superior resistance to intergranular stress corrosion cracking. Since the beginning of welding and fabrication of stabilized austenitic steels of type 347 the materials and filler metals have been improved to type 347 modified with limited C and Nb contents. To avoid any hot cracking problems, the chemical compositions of both base material and filler materials are specified to ensure the formation of sufficient delta ferrite levels. With these precautions, the material TP 347 mod. shows good welding behaviour and no fabrication problems in shop or on site. This is also confirmed by results of hot ductility test in a weld simulator apparatus.     

重复焊接对304不锈钢热影响区组织与性能的影响

采用自动钨极氩弧焊接（GTAW）工艺设计刚性约束坡口,制备了304不锈钢1次焊接和1~5次试样。采用光学显微镜、X射线衍射（XRD）、扫描电子显微镜（SEM）与电子背散射衍射（EBSD）技术对重复焊接试样的热影响区（HAZ）显微组织进行观察分析,并开展室温拉伸性能测试,研究重复焊接对显微组织与力学性能的影响。结果表明,重复焊接试样的HAZ显微组织主要由奥氏体和条状δ铁素体组成,随着重复焊接次数增加,HAZ奥氏体晶粒尺寸呈长大趋势,δ铁素体含量先减少后增加,组织择优取向由<101>转变为<111>,局域取向差逐渐增大;晶粒尺寸是影响抗拉强度和延伸率变化的主要原因,加工硬化致使试样屈服强度逐渐增加。      

The Laser Welding with Hot Wire of 316LN Thick Plate Applied on ITER Correction Coil Case

ITER correction coil (CC) cases have characteristics of small cross section, large dimensions, and complex structure. The cases are made of heavy thick (20 mm), high strength and high toughness austenitic stainless steel 316LN. The multi-pass laser welding with hot wire technology is used for the case closure welding, due to its low heat input and deformation. In order to evaluate the reliability of this welding technology, 20 mm welding samples with the same groove structure and welding depth as the cases were welded. High purity argon was used as the shielding gas to prevent oxidation because of the narrowness and depth of the weld. In this paper investigation of, microstructure characteristics and mechanical properties of welded joints using optimized welding parameters are presented. The results show that the base metal, fusion metal, and heat affected zone (HAZ) are all have fully austenitic microstructure, and that the grain size of fusion metal was finer than that of the base metal. The welding resulted in an increase of hardness in the fusion metal and HAZ. It was confirmed that the tensile strength of fusion metal was higher than that of base metal and the impact toughness value is higher than industry standard requirement. Thus, this welding process was determined to be reliable for manufacture of the ITER CC cases manufacture.     

Feasibility Study on Welding Structure of the HT-7U Toroidal Field Coil Case

1. IntroductionThe TF magnet system of HT-7U consists of 16coils arrayed toroidally and spaced 22.5" apart oneanother. The designed TF coils provide a magneticfield, which is necessary to maintain plasma in atokamak configuration with a current up to I MA.The TF coils have a D--shaped geometry of 3.5 meters high and 2.5 meters wide, producing a magneticfield of 3.5 T on 1.7 m of main radius. The TF coilcases, enclosing the TF winding packs, are the mainstructural components of the magn…     

Development of Manufacturing Process of PNC-FMS Wrapper Tube with SUS316 Short Joint

When a ferritic-martensitic stainless steel (PNC-FMS) wrapper tube having far greater swelling resistance against neutron irradiation is applied in the JOYO or MONJU reactor, it becomes necessary to weld it with SUS316 austenitic stainless steel (entrance nozzle and handling head). Such welding between PNC-FMS and SUS316 causes the delta (δ) ferrite formation at heat-affected zone, which leads to significant toughness degradation. In addition, bending of wrapper tube caused by their differential thermal expansion should be straightened. For preventing those problems, manufacturing process of the complex wrapper tube was developed. This process involves TIG-welding with SUS316 short pipe joints in 50mm length to both ends of a PNC-FMS round tube, and then performing the drawing and normalizing and tempering. Normalizing induces complete disappearance of the δ ferrite in the course of wrapper tube manufacturing. The mechanical properties of PNC-FMS/SUS316 welded zone were confirmed to be equivalent to those of the base metal even after thermal aging.     

碳钢对核主泵用奥氏体不锈钢的污染研究

奥氏体不锈钢在加工、运输和装配过程中如果与碳钢直接接触,就会被碳钢污染,而导致奥氏体不锈钢耐蚀性能的改变。众所周知,核主泵用奥氏体不锈钢对耐蚀性有着非常严格的要求,本文以Z2CN18-10核主泵用奥氏体不锈钢为例,通过FeCl3腐蚀试验和电化学方法测试了被碳钢污染后其耐腐蚀性能的变化。试验结果表明:附着在不锈钢表面的碳钢对其长期总体腐蚀速率影响不大;嵌入式的碳钢颗粒会显著降低奥氏体不锈钢的点蚀电位,增大发生点蚀的倾向;硝酸钝化可部分抵消被污染不锈钢点蚀电位的降低,但该值仍远低于同样经过硝酸钝化,而未被污染的不锈钢的点蚀电位。此外,还针对碳钢污染对核电站辐射场的影响和对燃料包壳热传导效率的影响进行了讨论。     

应变幅对国产锻造奥氏体不锈钢环境疲劳寿命影响的试验研究

为验证模拟压水堆核电站冷却剂服役环境对国产锻造主管道用奥氏体不锈钢疲劳寿命的影响,采用高温高压循环水疲劳测试系统对从产品锻件取样加工后的标准试样进行了低周疲劳试验,分析了试验数据与美国机械工程师学会(American Society of Mechanical Engineers,ASME)规范平均/设计疲劳曲线的关系,获得了应变幅对奥氏体不锈钢环境疲劳寿命的影响规律,并初步评价了ASME规范设计疲劳曲线和环境疲劳修正系数的适合性。