5月23日 焊前预热与焊后热处理方案 Rev.03.doc

BASF MDI Complex Chongqing ProjectMulti Discipline ConstructionThe Third Chemical EngineeringContract No: CO-CQ5522-92L-012Construction Company of China Rev.03, 25.May.2013File No: MDI-TCC-92L012-MS-039 Page 12 of 11焊前预热与焊后热处理方案Preheating and Post Welding Heat Treatment ProcedureMDI-TCC-92L012-MS-039325.May.2013Revised asTMDI comments218.Apr.2013Revised asTMDI commentsGAO BINXIA KAO FEIZHAO QI18,Mar,2013Revised asTMDI commentsGAO BINXIA KAO FEIZHAO QI014,Jan,2013Issue for approvalGAO BINXIA KAO FEIZHAO QIRevisionDateRevision DescriptionPrepared ByReviewed ByApproved By目录Contents 1. 概述General 2. 编制依据 References 3. 焊前预热与焊后热处理执行程序和计划 PWHT Execution Plan and Procedure 4. 硬度检查和无损检测 Hardness Test and RT 5. 标识管理 Marks Management 6. 附件 Attachments1.概述General为了降低和消除管道焊接应力，防止出现应力腐蚀裂纹。应用电加热的方法对焊缝进行热处理，热处理适用于碳钢(t 19mm)、和输送介质代码为701、702管道的管子、管件。我公司施工范围内的需要热处理的有A672-C60、A106-B两种材质。The procedure is prepared to reduce or eliminate the welding stress of pipe and avoid stress corrosion cracking. Do the heat treatment for the welding seams by using the electrical heating method. The heat treatment is suitable for the carbon steel (t 19mm), pipe and fitting which code for conveying medium is 701 and 701. There are two materials (A672-C60 and A106-B) need to do the heat treatment within the construction scope which is conducted by TCC. 2.编制依据 References 2.1GB/T20801-2006 压力管道规范-工业管道 Pressure piping codeIndustrial piping. 2.2GEN-0-PIPE-SP-0052 预制/现场管道的焊接与无损检测规范 Code for prefabrication/ site pipe welding and non destructive examination. 2.3GEN-0-TECH-SP-0008 焊接制作的基本要求 General requirements for welding fabrication2.4 ASME B31.3-2010 工艺管道 process pipe 2.5 热处理和无损检测地上管道汇总表(REV NO.1A)The summary sheet of heat treatment & non destructive examination for A/G pipe (REV NO.1A)3.0 焊前预热与焊后热处理执行程序和计划 PWHT Execution Plan and Procedure3.1焊前预热 Preheating3.1.1需要预热的碳钢焊口外径219mm或壁厚 20mm的管子采用电加热，电加热时用控温箱记录预热的温度并做好预热的温度曲线。The external diameter of carbon steel welded junction which are need do the heat treatment 219mm or the pipe which thickness of shell 20mm need use heat treatment. Record the preheating temperature by using temperature controlling box and the preheating temperature curve during the electrical heating.3.1.2所有需要预热的焊口如焊接时中断后继续焊接的焊口应重新预热。For all preheat required welding junctions, such as the welding junction which is re-welding after interrupting need to be preheated again. 3.1.3工程中需要预热的管线支管、管座，应优先采用液化石油气火焰预热，预热要求和相同公称直径的管子一样，加热区以外100mm应予以保温。For the branch pipe of pipeline and pipe seat during construction, shall be preheated by using liquefied petroleum flame priority. The requirement of preheat is the same as the pipe which has the same nominal diameter. Conduct the insulation for the 100mm outside the heating area. 3.1.4法兰块预热用块状式红外线高温陶瓷加热器，加热器用铁丝固定在法兰内部。The preheating for the flange shall use infrared radiation high temperature ceramic heater which is block type. Fix the heater inside of the flange by wire. 3.1.5预热时应在坡口两侧均匀进行加热，预热范围应以坡口中心两侧各不小于壁厚的3倍，且不小于100mm.When preheating, do the even heating at the two sides of groove. The preheating range shall be groove-centered, both of the two sides shall no less than 3 times of shell thickness and 100mm. 3.1.6预热温度见下表 the preheating temperature is shown in below table:Material typeWeld throat thickness(mm)Minimum preheat temperature(C)Carbon steelt12.71012.7 t258025 t501003.2 焊后热处理 Post weld Heat Treatment3.2.1 焊接完的需要进行热处理的焊口，应在焊接外观检查合格后进行热处理,热处理时管口应封闭;另外为了防止和降低热处理高温对阀门和仪表的负面影响，凡需要热处理的管线上，焊口附近阀门、流量计、调节阀、仪表原则上应予以拆除，对于不能拆除的部分应使其处于全开状态。After welding, for the heat treatment required welding junction, shall be do the heat treatment after the welding visual inspection is qualified. The open ends of pipe shall be sealed during heat treatment. Besides, in order to avoid and reduce the negative effect for valve and instrument from the high temperature of heat treatment. For the pipelines which require heat treatment, in principle, dismantle the valve, flow meter, regulating valve and instrument nearby the welding junction. But for the parts which cannot be dismantled, shall keep them in the state of fully opened. 3.2.2 采用电阻加热法，一般原则（NPS2）选用履带式加热器、（NPS2）绳型加热器，外包保温棉。所使用的温度显示仪表、记录仪表必须经过计量检查合格。 The general principle is to chose the crawler heater (NPS2) and cord type heater （NPS2）and wrap the insulating cotton outside for the resistance heating method. The used temperature display instrument and record instrument must be measuring inspected and qualified. 3.2.3 A672-C60、A106B管道热处理温度范围参照巴斯夫项目规范GEN-0-TECH-SP-0008，具体的热处理参数见热处理工艺卡。The temperature of piping heat treatment (A672-C60、A106B) refers to the BASF project specification GEN-0-TECH-SP-0008, the detail parameters for heat treatment is shown in heat treatment process card. 3.2.4 焊后热处理的加热速率、热处理温度下的恒温时间及冷却速率应符合下列规定。The heating rate, temperature holding time and cooling speed of Post Weld Heat Treatment (PWHT) shall be in accordance with the following specifications. A .300以上加热/降温速率受控制，300以下随热处理设备升温，温度降到300时覆盖保温棉自然冷却。The heating rate shall be controlled for the temperature above 300 and heating-up along with the heat treatment equipment for the temperature below 300. When the temperature reduces to300,the covered insulating cotton is in the natural cooling. B. 当温度升至300以上时，加热速率不应大于205（25/）/h, 且不得大于205/h（为公称管道壁厚）。When the heating temperature is over 300,the heating ratio shall be not more than （205*25/）/h, and no more than 205/h（ refers to the thickness of nominal pipe） C. 焊后热处理的恒温时间应为每2.5min/mm，且不得少于1小时。 The temperature holding time of PWHT shall be 2.5min/mm, and shall no less than 1 hour 。 D .恒温后的冷却速率不应大于260（25/）/h且不得大于260/h，300以下可自然冷却。After holding temperature, the cooling speed shall not be greater than (260*25/) /h, and no more than 260/h. for under 300, can be natural cooling.3.2.5 A672-C60、A106B热处理曲线如下：PWHT curve of A672-C60、A106B is as follows:t (h) cooling rate260/hand (26025/)/h Heating rate205/hand (20525/)/h 0T()640593300Holding time(*1/24)hour，min. 1hour 3.2.6 热处理工序控制Control of PWHT working Procedure A .在热处理前要按照要求将热处理设备和人员资质报验给TMDI的 QA/QC ，对热处理操作人员进行技术交底。Before the commencement of PWHT, the PWHT devices and personnel qualification are required to submit to QA/QC of TMDI for approval according to the requirements. Conduct the technical clarification for the operation personnel of heat treatment. B. 按照热处理和无损检测地上管道汇总表的要求，施工单位的质检人员必须在现场对需要热处理的管线号、焊口号进行确认，同时得到TMDI的QA/QC相关人员检查确认，热处理才能进行。According to the requirements from the summary sheet of heat treatment & non destructive examination for A/G pipe, QA/QC personnel of construction team must confirm the pipeline number and welding number which require heat treatment on the site. And get the inspection confirm from QA/QC of TMDI at the same time. The heat treatment shall be conducted as per this procedure. 3.3 热处理中注意事项 Attention items for PWHT： 加热器要紧贴焊缝。 The heater shall be attached with weld seam closely. 保温要均匀、严密，不能厚薄不均匀。 Heat insulation shall be uniform and tight. Non-uniformed thickness is unable. 法兰焊接的焊后热处理，整个法兰面（包括内外面）都要进行保温。For the post welding heat treatment of flange welding, the insulation shall be conduct for the whole surface of flange (include the inside and outside). 对于局部热处理，焊缝每侧加热加热范围不应小于焊缝宽度的6倍或不小于150mm,或者根据规范要求，三个数值以最大值为标准。加热器以外250mm或者规范要求的范围内进行保温，两个数值以最大值为标准。For the partial heat treatment, the heating range of weld seams at each side should be no less than the 6 times of weld thickness or no less than 150mm. Or according to the requirement of specification, take the maximum value as the standard among the three values. For the 250mm outside the heater or the insulation within the range of specification requirement, take the maximum value as the standard between the two values. 为了防止由于辐射影响造成温度误差，所有连接的热电偶都应被保温，保温采用50600硅酸铝纤维保温棉进行保温，并使用铁丝进行绑扎，避免脱落。All the thermocouple attachment shall be adequately insulated to avoid temperature misreading caused by the effect of radiation. Hold the temperature by using 50*600 aluminum silicate fiber insulation cotton and wrap by wire to avoid dropping. 应依据设计规范设定热电偶的数量和位置.焊缝的每个测温点需要一个热电偶进行控制，且测温点的温差必须小于50。对于管道的局部热处理，热电偶的数量应参考下列数据。Set the quantity and location of thermocouple as per design specification. Each point for measuring temperature need be controlled by a thermocouple. And the temperature head of temperature measuring point must be lower than 50. For the partial heat treatment of pipe, the quantity of thermocouples shall refer to the following data. 热电偶应在焊口表面，其附件仅允许采用电阻焊接或螺栓-螺母连接，热电偶去除后应检查焊点区域是否有缺陷，具体布置要求见下表：The thermocouple shall be at the surface of welding junction. The fitting shall be connected by only use the resistance welding or bolt-nut. Check if there are defects in the welding spot area after removing the thermocouple. The detail arrangement requirement as follows:尺寸（size）Layout position of the thermocouple 热电偶布置位置D 4”NPSone thermocouple at 12 oclock position 12点的位置放一个热电偶4”NPS D 12”NPS- one thermocouple at 12 oclock position and one at 6 oclock position12点位置和6点位置分别放一个热电偶。D 12”NPSfour thermocouples equally spaced around circumference围绕周长均匀的放置4个热电偶。Sketch:NPS44NPS12NPS12 电加热器、热电偶、硅酸铝保温棉都包好后，将加热器、热电偶，连线分别连接，确认无误后，接通电源、打开温控仪、按照工艺参数调节好各个参数，向电加热器送电，开始加热。预热与焊后热处理采用热电偶测温，通过温度控制柜进行温度控制、通过温度记录仪记录热处理变化曲线。After wrap the electric heater, thermocouple and aluminum silicate insulation cotton, connect heater, thermocouple and connected wire, respectively. And after confirmed correct, power on, open the temperature control unit and adjust each parameter as per the process parameter, apply the power to electrical heater and begin to heat. Measure the temperature of preheating and PWHT by using thermocouple, control the temperature via temperature control cabinet, and record the changing curve of heat treatment via temperature recorder. 3.4 热处理记录的管理 The management of records for heat treatment. 热处理前，在热处理记录纸上由技术员填写管线号、温控图号、焊缝编号、日期、热电偶编号、热电偶位置简图、操作人姓名，并由TMDI QA/QC相关人员检查签字确认。Before PWHT, technical personnel should fill in the record: line No, temperature control figure NO, weld No, the date, thermocouple No, sketch of thermocouple location, operators name. Then related TMDI QA/QC inspector checked and sign for confirm.热处理后由TMDI QA/QC对以上确认及对工艺曲线图审核，合格后签字确认。After PWHT, TMDI QA/QC shall confirm the above mentioned and review the process curve chart. Then sign after acceptable. 记录的整理：由技术人员对记录进行整理，并编制热处理报告,所有焊后热处理报告应提交给TMDI QA/QC进行确认。Clear-up of record: the technical personnel shall clear up all the record, and prepare PWHT report. All PWHT report (including PWHT charts) shall be submitted to TMDI QA/QC for approval.4.0 硬度检查和无损检测 Hardness Test and RT4.1为了检验处理效果，局部热处理结束后，按照GB/T20801-2006的要求进行100%硬度检测。For the inspection treatment result, do 100% hardness test as per the requirement of GB/T20801-2006 after finishing the partial heat treatment. 4.2硬度检验分别在焊缝，热影响区、母材。在测量每一点硬度时，要求测量三次取平均值，要求测试值小于布氏硬度值200。The hardness test shall be conducted for weld seams, heat affected zone and base materials. When survey the hardness at each point, shall survey for 3 times and take the average value of them. The survey value shall be less than the value of brinell hardness 200. 4.3硬度测试值不合格后按照要求,重新进行焊后热处理。If the value of hardness test is unqualified, the post welding heat treatment shall be conducted again. 4.4硬度检测合格后按照要求进行NDE检测，如果检测不合格，应返修焊缝，并重新进行PWHT和NDE。Conduct the NDE test after the hardness test is qualified. If the test is unqualified, the welding seams shall be repaired and conduct the PWHT and NDE again. 5.0 标识管理 Marks Management 需做热处理的焊缝标识与焊缝距离保持在200mm以上，直管段太短时可写在配件上面；管径DN8”的焊缝标识，对称两侧标注，如果在热处理前发现焊道标识太靠近焊缝，由热处理人员移植到热处理范围外，热处理完毕后，再进行恢复。For the weld seams, which need PWHT, marks shall be 200mm apart from weld seams .If the straight pipe section is too short, the mark can be made on the connected pipe. For the marks of DN8pipes, make marks symmetrically at the both sides of pipe. If the weld mark is too nearly the weld, the weld marks shall be moved outside of PWHT area prior to PWHT, and restore them afterwards.6.0、 附件 Attachments 6.1、热处理报告PWHT report format6.2、硬度报告Hardness report format6.2 Attachment #2: PWHT Report format合同名称： 工程编号：Contract Name Project No.:合同号:Contract No.:SH/T 3503-J411-1管道焊接接头热处理报告（一）Pipeline Welding Joints Heat Treatment Report （I）工程名称： Project：单元名称：Unit：管道编号Pipeline No.报告编号Report No. 热处理方法HT method热处理设备HT equipment焊接接头编号Joint No测温点编号Temp. detectingpoint