不锈钢等离子弧焊接质量的控制（上）

纺织机械行业大量生产化纤机械和染整机械,这类产品大都是12mm以下的奥氏体不锈钢焊接结构。一般3mm以下的不锈钢板,普遍采用钨极氩弧焊,工艺稳定可靠,具有很高的焊接质量和生产效率。4～12mm的不锈钢板,曾经采用埋弧自动焊、熔化极氩弧焊,焊接效率也很高,但坡口准备工时长,用一次焊透、双面成形工艺时,规范控制要求高,容易产生烧穿。使用带铜垫     

奥氏体不锈钢双面同步手工钨极氩弧焊打底技术的研究与应用

采用正交试验分析法对奥氏体不锈钢双面同步手工钨极氩弧焊打底技术进行了研究试验,获得了试验数据,并对数据进行了整理分析,得出了影响手工钨极双面同步氩弧焊打底技术质量的主要影响因素。确定了此种方法的焊接工艺、焊接操作技术,并进行了现场应用效果和经济性分析。     

不锈钢AA-TIG焊接法

针对不锈钢,提出一种新型活性TIG焊方法——电弧辅助活性TIG焊,即AA-TIG焊。采用CO2+Ar作为小电流钨极电弧的保护气体进行单弧AA-TIG焊,分别研究小电流钨极电弧和正常TIG焊工艺参数对焊缝熔深的影响,并针对试验范围内的最佳焊接规范研究不锈钢AA-TIG焊的焊缝成形、焊缝显微组织、化学成分和焊缝性能。采用AA-TIG焊可以单道焊透10mm厚的不锈钢板材,单面焊双面成形。与传统TIG焊相比,焊缝组织和化学成分几乎没有变化,焊缝的耐Cu/CuSO4腐蚀性能和低温冲击韧度都满足相关标准要求。     

奥氏体不锈钢电子束单面焊双面成形焊接技术

对奥氏体不锈钢电子束单面焊双面成形焊接技术进行研究,通过焊接试验,获得电子束焊缝全部焊透,背面无明显焊瘤,成形良好的奥氏体不锈钢电子束单面焊双面成形焊接工艺参数.     

大型半球形铝合金封头双面垂直氩弧焊

直径Φ3800mm、厚度12mm的大型铝合金半球形封头，由瓣片和顶圆拼焊而成。采用双面垂直氩弧焊，I型坡口，双人施焊，不预热，可以一次焊接成形。焊缝表面和内在质量符合设计要求，是一种新型高效焊接方法。     

0Cr18Ni9手工钨极氩弧焊和电弧焊工艺对比

文中讨论了奥氏体不锈钢焊接技术,通过0Cr18Ni9（δ=3mm）手工钨极氩弧焊和电弧焊焊接之间的工艺及性能对比（均采取单面焊两面成形）,介绍了薄板手工钨极氩弧焊焊接工艺的优点,为不锈铜材料焊接提供了一种很好的焊接技术。     

CO2气体保护焊单面焊双面成形技术

锅炉及压力容器等重要结构的焊接，要求接头完全连接。有的结构由于尺寸和形状的限制，不适于甚至无法双面施焊，只能在容器单侧进行焊接。因此研究C02气体保护焊单面焊双面成形技术，并与手工电弧焊进行全面比较是将C02气体保护焊推广应用到锅炉及压力容器等生产中的关键之一。为此，文中对CO2气体保护焊单面焊双面成形的工艺因素、工艺条件等加以论述，并以相应的实验数据证明了单面焊双面成形的焊接质量的可靠性。     

氧乙炔焊薄铝机壳单面焊双面成形的焊接工艺

用氧乙炔焊薄铝机壳,做到单面焊双面成形,不仅要掌握铝及铝合金的焊接性能,还要求选用合理的焊接工艺和熟练的焊接技术。我厂有时遇到电机铝壳在压装过程中被压裂的问题,为了挽回经济损失和生产时间,在没有实践经验的前提下,我们考虑到小铝机壳内部不便焊接和二次焊接温度对材质发生变化的影响,经过实践摸索和总结,大胆采用了氧乙炔单面焊双面成形的方法,制定了焊接工艺。后经检验,效果非常好。现将焊接小铝机壳单面焊双面成形的体会介绍如下,供大家参考。     

双面同步TIG焊在大型铝镁料仓焊接中的应用

大型铝镁料仓焊接工程量大，焊接质量要求高，选择合适的焊接方法对焊接质量、工期有着重要的影响。本文系统介绍了双面同步钨极氩弧焊（TIG焊）在大型铝镁料仓焊接中的应用技术。此项技术在类似工程中有着很好的应用推广前景。     

厚板硬铝合金焊接工艺设计和接头分析

本课题研究并制定了10mm厚板硬铝合金的TIG焊与A-TIG焊的焊接工艺,并对TIG焊与A-TIG焊在不同电流条件下的焊接接头进行了分析。本文着重研究了当采用TIG焊和活性化钨极氩弧焊(A-TIG)方法焊接厚板硬铝合金时,焊接电流的变化对组织及焊缝成形的影响,以及活性剂的加入对提高厚板硬铝合金熔深和金相组织的影响。     

自动脉冲气保焊单面焊双面成形工艺在压力管道和压力容器上的应用

介绍了自动脉冲气保焊的工艺特点，试验结果表明，自动脉）中气保焊单面焊双面成形工艺所焊制的接头性能能够满足压力容器和管道焊缝使用性能的要求；在压力管道和小规格的压力容器的焊接方面，自动脉冲气保焊单面焊双面成形工艺是传统的氩弧焊打底焊条电弧焊盖面工艺的比较理想的替代方法。     

YAG激光与GTAW复合焊接铝合金

研究了YAG激光、GTAW电弧复合焊接铝合金时各种规范参数对焊缝成型的影响规律 ,探讨激光与电弧的复合作用机理。结果表明 ,采用YAG激光 +GTAW复合工艺焊接铝合金具有焊缝成型美观、热影响区小等优点 ,与GTAW焊接相比 ,焊速显著提高 ,可以显著增加熔深 ,达到采用小功率激光焊机实现铝合金的焊接目的 ,Laser、GTAW是铝合金焊接理想的工艺方法。     

焊接过程的神经网络建模及控制研究

采用人工神经网络方法对焊接过程进行建模及控制，并以ＧＴＡＷ作为对象加以实施。用误差反传网络（ＢＰ网）建立了静态过程ＧＴＡＷ熔透情况下表征其质量的正面熔宽、背面熔宽与施焊参数之间的关系，即静态模型，并从质和量两个方面验证了该模型的可行性。提出了采用两个网络对ＧＴＡＷ动态过程建模及控制的方法，并通过实验验证了所提方案的正确性。文中所提的方法从根本上不同于以往的以固定结构数学模型为基础的建模及控制的方法，无需对过程作任何假设，所建模型与实际过程符合较好。实验证明，该方法具有容错性好、通用性强和抗干扰能力强等优点，为焊接过程的建模及智能化控制找出了一条新途径。     

An adaptive inverse control method based on SVM–fuzzy rules acquisition system for pulsed GTAW process

This paper proposes a new method of adaptive inverse control based on support vector machine–fuzzy rules acquisition system (SVM-FRAS) for the gas tungsten arc welding (GTAW) process. In this control mechanism, an identifier is established based on SVM-FRAS, and an inverse controller based on SVM-FRAS is designed. The proposed adaptive inverse control method can automatically extract control rules from the process data. Comprehensibility is one of the required characteristics for a complex GTAW process control. We use the proposed SVM-FRAS-based adaptive inverse control method to obtain the rule-based process and the control model of the aluminum alloy pulse GTAW process. Based on the simulation experiments for GTAW process, the SVM-FRAS adaptive inverse control method is found to be effective.     

阀门密封面钴基合金堆焊工艺

介绍了阀门密封面常用材料堆焊钴基合金(焊丝)的化学成分、牌号类别和熔敷金属层常有的缺陷。论述了手工钨极氩弧焊(GTAW)的工艺验证方法。总结DN300奥氏体不锈钢三偏心蝶阀密封面堆焊钴基合金的质量控制。     

Three-dimensional vision-based sensing of GTAW: a review

Automated and robotic welding is now widely used in manufacturing industry. The control of the welding process plays a crucial role in producing quality welds in automated and robotic welding where the assistance from skilled welders is no longer available. In gas tungsten arc welding (GTAW) which is the primary arc welding process for precision joining of metals, the weld pool is the major source of information that can be used to assure the production of desired weld penetration which is the most critical factor determining the weld integrity. To meet this challenge, various sensing technologies have been proposed/studied to sense and obtain the feedback for the weld pool state. This paper summarizes the researches on weld pool state sensing: conventional sensing technologies, vision sensing technology, and multi-sensor information fusion technology, with emphasis on the analysis of three-dimensional vision sensing methods. And three-dimensional vision sensing, multi-sensor technology, intelligent modeling, and effective commercial product development show the future trends of GTAW penetration sensing.     

Effect of welding processes on tensile properties of AA6061 aluminium alloy joints

The present investigation is aimed at to study the effect of welding processes such as GTAW, GMAW and FSW on mechanical properties of AA6061 aluminium alloy. The preferred welding processes of these alloys are frequently gas tungsten arc welding (GTAW) and gas metal arc welding (GMAW) due to their comparatively easier applicability and better economy. In this alloy, the weld fusion zones typically exhibit coarse columnar grains because of the prevailing thermal conditions during weld metal solidification. This often causes inferior weld mechanical properties and poor resistance to hot cracking. Friction stir welding (FSW) is a solid phase welding technique developed primarily for welding metals and alloys that heretofore had been difficult to weld using more traditional fusion techniques. Rolled plates of 6 mm thickness have been used as the base material for preparing single pass butt welded joints. The filler metal used for joining the plates is AA4043 (Al-5Si (wt%)) grade aluminium alloy. In the present work, tensile properties, micro hardness, microstructure and fracture surface morphology of the GMAW, GTAW and FSW joints have been evaluated, and the results are compared. From this investigation, it is found that FSW joints of AA6061 aluminium alloy showed superior mechanical properties compared with GTAW and GMAW joints, and this is mainly due to the formation of very fine, equiaxed microstructure in the weld zone.     

Study on the welding technology of a pleated type metallic filter using micropulse gas tungsten arc welding

The welding technology of a pleated type metallic filter is an important factor when considering influences on filter quality. In this study, micropulse gas tungsten arc welding (GTAW) was used to weld the pleated type metallic filter. The micropulse GTAW is a multivariate process with a variety of welding parameters that work in pairs, and parameter optimization is necessary in order to achieve high welding quality. For this study, the micropulse GTAW process parameters are optimized using response surface analysis in order to produce high-quality pleated type metallic filter welds. The process parameter values found through optimization are as follows: a pulse current of 20.34 A, a base current of 5.8 A, a pulse duty of 32.01%, a frequency of 10.34 Hz, and a welding speed of 0.21 cm/s. Using the hydraulic pressure estimation model, the pressure was estimated to be 155.8 mmH₂O. The welding experiment was performed under optimal conditions in order to evaluate the efficiency of the hydraulic pressure estimation model. The actual hydraulic pressure was 152 mmH₂O, which confirms the performance reliability of the hydraulic pressure estimation model.     

1Ni9钢在乙烯压缩机上的应用

阐述了-150℃工作的1Ni9低温用钢进行的焊接、热处理试验及焊接工艺评定等工作;并针对材料的焊接性能和产品特性设计了焊接叶轮的坡口型式及焊接工艺。完成了焊接力学性能试验、评价焊接材料,完成了工艺性试验、通过试验测定焊接收缩性能、制定焊接收缩量、评定-150℃焊接接头性能及焊接性能,确定产品叶轮焊接及焊后热处理工艺。