管道环焊缝多焊炬自动内焊机关键技术分析

管道环焊缝自动内焊机主要用于管道环焊缝焊接施工中的管口组对和根焊焊接,相比其它的根焊设备和技术,内焊机完成根焊质量可靠,效率最高.重点研究了长输管道环焊缝多焊炬自动内焊机的总体设计、数字式控制系统、细丝焊接电弧的控制及环焊缝自动内焊工艺等关键技术.现场实际应用表明,研究出的环缝多焊炬自动内焊机结构合理、控制先进,完成一个环焊接头根焊用时仅90 s.其可靠性和野外环境适应性完全满足现场焊接施工要求.

Abstract：

The pipeline internal circumferential automatic welding machine (PIW machine) has been mainly used for pipe alignment and welding root pass in course of pipeline construction. Compared with the other root pass equipment and technologies, PIW machine has the higher efficiency and better root quality. This paper researches the key technologies such as the entire design of PIW machine with multi-torches, digital control system, arc-control for small size wire and the internal welding process. The site application indicates PIW machine with multi-torches has the advantages of reasonable structure and advanced control system, its welding speed is 90s per joint. Its reliability and the filed adaptability to environment meet the site welding construction request completely.     

An experimental study of the fracture properties of oil pipeline girth welds

The application of fracture mechanics to the "Fitness For Purpose" assessment of the fracture properties of pipeline girth welds is generally essential for the safe operation of oil pipeline systems. Based on the analysis of the fracture toughness requirements of the oil pipeline girth weld, a systematic study has been conducted on the fracture behavior of the API 5L X65 steel pipelin egirth weld made by two welding materials. The critical COD values of the pipe line girth weld under the different temperatures are tested. In the paper other influential factors on fracture behavior are also discussed, such as the welding materials, the welding positions (flat welding, vertical welding, overhead welding), the welded joint area (weld, heat-affected zone, fusion line and base metal) and the experiment temperature. The result shows that the welding material, the welded joint area and the experiment temperature have considerable influence on the fracture behavior of pipeline girth welds. It is also concluded that t he effect of the welding position is related to the welding process. The study provides a scientific basis for the welding of oil pipelines.     

大厚壁管扁焊枪的改进优化

随着国内二代半、三代核电站的规模化建造,窄间隙自动焊工艺被广泛应用于主回路管道焊接过程中。主管道焊接采用自动焊标准大焊炬,焊接过程中需要消耗大量的保护气体,且易受外界环境的影响,不便于进行量化控制,成本较高,这些因素很大程度上制约了自动焊技术的推广和普及。基于自动焊焊机自身特点,借鉴国外的成熟扁焊枪经验,分析焊枪结构,设计能够匹配自动焊焊机的焊枪结构,使得该扁焊枪可深入至焊缝表面进行近距离保护,大大减少所需保护气体流量,且不易受外界环境影响,保护效果更佳,便于量化控制。     

Numerical simulation of stress and deformation of in-service welding onto gas pipeline

SYSWELD was used to simulate in-service welding process of gas pipeline of X70 pipeline steel. Welding thermal cycle, stress and deformation of in-service welded joint were studied. The results show that peak temperature of coarse grain heat-affected zone （CGHAZ） of in-service welding onto gas pipeline is the same with routine welding, but ts/5, ts/3 and ts/1 decrease at certain degree. For the zone near welded seam, axial stress and hoop stress in the inner pipe wall are compressive stress when welding source passes through the cross-section that is studied, but residual axial stress and residual hoop stress after welded are all tensile stress. Transient deformation and residual deformation are all convex deformation compared with the original pipe diameter size. Deformation achieves maximum when welding thermal source passes through the cross-section that is studied and then decreases during the cooling process after welding.     

核电厂管道卡钳式全位置自动焊工艺

针对传统焊接方式已不能满足当前核电工程建设和未来核电检修需要的现状,通过前期的市场调研、设备选型、工艺开发和工程应用等过程,研究出一套成熟的卡钳式全位置自动焊方法用于核电厂现场管道的焊接,可有效节约成本、保证焊接质量、提高施工效率,为后续核电厂管道领域自动焊的推广应用提供参考和借鉴.     

石油天然气管网资产完整性管理思考与对策

以自动焊为代表的第三代管道建设技术已在中俄东线天然气管道工程等国家重点油气长输管道工程中全面应用。通过梳理近年来管道工程自动焊质量管理经验,围绕人、机、料、法、环5个方面,从焊接工艺评定、焊工准入、焊材管理、百口磨合、连头口焊接、焊接数据采集及焊口分析等环节,对环焊缝质量管控措施开展系统性总结。结合“中国制造2025”,展望了未来油气管道建设事业的发展,为焊接新技术的开发应用和质量管控提供参考。

     

移动式钢管"二接一"焊接装置的研制

介绍了在“西气东输”国家重点工程中采用的一种新的钢管对接焊设备和工艺,对长达25m的钢管对焊接过程作了重点介绍了,并对壁厚为14.6mm,直径为1016mm的钢管自动埋弧焊工艺及装备进行了研究,该设备经野外现场使用,焊接质量和效率均比其他设备有较大的提高。     

长输管道自动焊接设备及技术发展

随着社会技术进步和人类对石油和天然气需求量的急剧增加,长输管道在向着大口径、长距离、高压力、高钢级方向发展,焊接技术及相关的设备、材料性能也在同步提高,与之相适应的管道焊接技术也在发生着巨大的变化。管材钢级从X42提高到X80;焊接材料从纤维素焊条到自保护药芯、金属粉芯、实心等各种焊丝;焊接方法从手工上向焊到手工下向焊,到药芯自保护半自动焊,再到气保护半自动焊、自动焊,管道焊接技术日趋成熟。结合长输管道施工特点,在分析国内外管道焊接技术差异的基础上,提出我国现阶段长输管道焊接技术发展的建议。     

Research on key control technologies of all-position automatic welding machine

The pipeline all-position automatic welding machine system is a special welding system for automatically welding circumferential joint of pipeline on site, which has been widely used to the long-distance pipeline construction projects due to the advantages of automatic control for welding parameters at all-position, moving speed of bugs and operating. In this paper, the key control technologies of PAWM all-position automatic welding machine (developed by Pipeline Research Institute of CNPC) such as the automatic control system, control software, personal digital assistant (PDA) software and complex programmable logic device(CPLD) program as well as the control method of welding parameter have been described detailedly. With the higher welding quality, higher welding efficiency and lower labor intensity, PAWM all-position automatic welding machine has been successfully applied in many famous pipeline construction projects.     

中卫-贵阳联络线工程山区返修焊接工艺

在山区,沿地表铺设的长输管道会产生不同程度的弯曲,弯曲的管道将给焊接返修带来一定困难。当返修点位于焊口拉应力位置时,切开焊缝金属极易在切口处产生新裂纹,可采用吊管机等起重设备减小管道弯曲程度从而减小返修处的拉应力。在中卫-贵阳联络线干线工程中,通过对X80管线钢焊缝返修工艺的分析,总结了在山区进行返修的焊接经验和技术方法,确定了改善焊缝受力状态、清除焊接缺陷以及施焊的具体措施,提高了焊缝返修的合格率。     

Influence of interpass temperature on the properties of duplex stainless steel during welding by submerged arc welding process

Duplex stainless steels are materials that present high corrosion resistance with high values of mechanical strength, therefore motivating their use in various components in the offshore industry. However, there are major challenges in the welding of these materials in terms of the productivity and quality of the joint produced, considering its extensive use for components of small thickness, such as umbilicals, to those of large thickness, such as salt water injection pipelines. In relation to pipes of small thickness, the gas tungsten arc welding process is successfully used. In thick-walled pipes, the automatic process of submerged arc welding (SAW) has been recently implemented in lines of pre-assembled piping, and this has considerably increased the productivity of the joints produced, though, a great deal of time is required to perform a new weld pass, due to the fact that the maximum interpass temperature needs to be lower than 150 °C. This work presents the results of characterization and the evaluation of corrosion resistance of a welded joint corresponding to DSS UNS S31803, with a wall thickness of 21.4 mm, welded by the gas metal arc welding process in the root and SAW process in the filling and cap passes, employing an interpass temperature between 150 and 290 °C. The results of the characterization of the mechanical properties, chemical composition and corrosion resistance in different regions of the welded joint were compared with those obtained for the base metal of the pipe, as well as with the minimum values required by the project standards. Therefore, this study has made an evaluation of the influence of the interpass temperature in the properties of the joints produced, motivated by a possible increase in productivity in pipe welding.     

管道全位置自动焊机的专用电源及焊接工艺

管道窄间隙全位置焊接过程中,在接近仰焊位置容易出现焊接缺陷,制约了管道施工的质量和效率.文中针对管道自动焊仰焊位置成形差、可靠性低的问题,分析P-GMAW过程送丝速度、弧长修正、导电嘴到熔池距离等因素对熔滴过渡的影响规律.结果表明,增加弧长修正系数可以增大电弧对侧壁的热输入,能够缓解侧壁熔合不良的问题,但会使熔滴过渡路径难以控制.因此当焊枪运动到仰焊位置时,提高送丝速度有利于获得更小的熔滴、更高的过渡频率;降低导电嘴到熔池距离,可以增加电磁力、减小熔滴尺寸,从而更有利于仰焊位置熔滴向熔池的过渡,研究结果对于管道窄间隙焊接的工艺设计具有一定的指导意义.

     

中俄原油管道二线工程RMD半自动+NOREAST自动焊焊接工艺

为满足中俄原油管道二线工程的质量要求,研究第三标段施工现场所使用的RMD半自动打底+NOREAST自动焊热焊、填充和盖面工艺。焊出的焊口先进行RT和AUT检测,检测合格后再进行力学性能试验。试验结果表明,该焊接工艺完全满足现场施工技术要求,现已将该套焊接工艺成功投入到中俄原油管道二线工程,并取得了良好的效果以及业主的一致好评。     

基于正交试验设计的高温管道焊接工艺优化

P91耐热钢焊接接头广泛用于电厂管道,厚壁管道焊接残余应力分布比较复杂,而焊接接头残余应力的大小对其高温环境下运行的蠕变又有着较大的影响.文中运用正交试验设计方法,以焊接残余应力为评价指标,对P91耐热钢管道焊接的工艺参数进行优化没计,然后采用大型有限元分析软件ABAQUS对最优焊接工艺的焊接残余应力进行数值模拟,获得了P91厚壁管道焊接接头的残余应力分布状况.结果表明,焊接速度对焊接残余应力的影响最为显著,其次电弧电压、焊接电流和坡口间隙等.研究结果为优化高温管道焊接工艺,有效控制焊接残余应力提供了可能.     

管道水平固定全位置熔化极机动焊接工艺

管道全位置自动焊接是指在管道相对固定的情况下,依靠电气、机械等方法,使焊接小车带动焊枪沿着固定轨道环绕管壁运动,通过自动送丝以及PLC控制等技术来实现自动焊接。研究管道全位置自动焊的焊接工艺以及焊接设备的目的是在确保接头质量的基础上提高焊接效率,同时降低焊工的劳动强度。工程施工中对管道焊接质量要求越来越高,通过反复焊接试验,各施工企业逐渐摸索和掌握全位置管道机动焊的焊接参数和焊接要领,为提高施工现场的管道全位置焊接施工效率和质量提供了参考和依据。     

长输管道自动焊施工资源配置及经济性分析

长输管道自动焊具有焊接质量好、效率高和劳动强度低等多种优势,较好地解决了高等级钢焊接质量和管道运行安全问题.但对于管道施工单位而言,使用管道自动焊技术和工艺,人员、设备等资源投入巨大,施工成本显著增加,而多数管道施工单位自动焊实际施工效率远低于其理论施工效率,致使施工单位出现投入大、产出少的状况,影响管道自动焊技术的推...     

主管旋转式相贯曲线自动焊接模型与仿真

相贯管道的主管旋转式焊接方式能够实现相贯焊缝的全过程平角焊,降低工艺复杂度并提高焊接质量. 为了实现相贯管道的自动化焊接,建立了主管旋转式相贯曲线自动焊接模型. 以一般性相贯管道几何模型为基础,用齐次变换矩阵分析了焊缝特征和焊枪姿态,得出了主管旋转角的变化规律及焊枪与世界坐标系的空间位置关系. 利用MATLAB和OpenGL对相贯管道的几何模型和焊接过程的运动模型进行了仿真. 结果表明,该自动焊接模型是可行的,可以用于主管旋转式相贯曲线自动焊接的实时插补或离线编程.     

涩-宁-兰管道工程中的焊条电弧焊和药芯焊丝半自动焊混合焊接工艺

介绍了涩-宁-兰输气管道工程中采用“焊条电弧焊 药芯焊丝半自动焊”焊接X60管材的工艺和X70管材的对照实验。根据施工实际，给出了该工艺的操作要点，指出该混合焊接工艺在西气东输管道工程焊接施工中有着很好的应用效果和前景。     

基于熔池受力的全位置STT打底焊分段工艺

油气管道在全位置焊接时通常按照固定角度机械化地进行分段,此过程中,熔池容易发生失稳流淌而导致焊缝成形不良。文中对管道全位置焊接过程中的熔池受力进行了分析,建立了一种基于熔池径向力变化的新型分段工艺,以解决全位置焊接时管道内、外壁成形不良的问题。通过对220 mm×10 mm×400 mm的X70管线钢采用STT打底焊试验发现,该分段工艺抑制全位置焊接时的熔池失稳流淌问题有良好效果,且内壁成形更加平滑美观,对于管道自动焊接过程中的分段问题具有一定的参考价值。创新点： 根据熔池径向力变化提出了新型的分段工艺,该工艺下管道内、外壁成形更稳定、失稳倾向减小。     

X100管线钢埋弧焊匹配焊剂及其接头性能分析

采用均匀设计法对X100管线钢埋弧焊用烧结焊剂进行设计,选用其中5种高碱度氟碱性焊剂,配合焊丝进行埋弧自动焊接试验,着重分析了两种焊剂焊接接头的拉伸性能、金相组织、硬度、冲击吸收功及冲击断口形貌等.结果表明,焊剂中适量添加MnO对焊剂工艺、接头韧性有较大影响,它可以提高焊缝熔深,增加渣的流动性,抑制咬边,同时抑制高温铁素体的生成而对焊缝中针状铁素体的形成有利.所研制的5种焊剂中,2号焊剂焊接接头综合性能最佳,满足X100管线钢API—5L标准要求.