小松PC系列挖掘机液压伺服系统恒功率控制分析

通过对小松PC系列挖掘机液压伺服系统的工作原理和工作过程分三种情况进行阐述,对小松PC系列挖掘机液压伺服系统恒功率控制进行了分析。     

高温合金GH4169氩弧焊接头的高温组织和力学性能

通过650℃高温拉伸和高温持久拉伸试验和光镜分析手段,对高温合金GH4169氩弧焊接头的组织形态和力学性能进行了研究.结果表明:接头的高温抗拉强度优于母材,但塑性显著下降,高温持久强度接近母材.母材基体组织为奥氏体,其上弥散析出γ′、γ″强化相,接头基体组织为树枝状奥氏体,树枝晶间有针片状的析出相,近缝区母材晶粒过热长大,是焊缝的薄弱环节.     

船舶焊接技术专业“一体化”教学模式研究与实践

船舶建造的关键技术之一是船舶的焊接技术。我国船舶工业的快速发展对高职院校加快培养大批高素质技能型船舶焊接技术专门人才提出了新的更高的要求,传统的教学观念和模式已经难以适应现代职业技术教育的发展,因此需要进行教学体制的改革,建立起适应专业特点和课程特点的"一体化"教学模式,以满足船舶工业对船舶焊接技术专业高技能人才的需求。     

谈钢筋焊接质量的提高

目前公路施工中所有的钢筋焊接都是由手工完成的,可以说焊工的技术水平在很大程度上代表了焊件的质量,只有提高焊工的技术水平,严格执行焊接工艺,在焊接材料的保管上注意方法,加强管理,才能从根本上解决焊接节点的质量问题。     

A Generalized Rough Set Modeling Method for Welding Process

Modeling is essential, significant and difficult for the quality and shaping control of arc welding process. A generalized rough set based modeling method was brought forward and a dynamic predictive model for pulsed gas tungsten arc welding (GTAW) was obtained by this modeling method. The results show that this modeling method can well acquire knowledge in welding and satisfy the real life application. In addition, the results of comparison between classic rough set model and back-propagation neural network model respectively are also satisfying.     

Path Planning of Planar Kinked Line Seam by Visual Servoing for Robotic Welding

Welding path planning can substitute for the manual teaching process of the robot and can promote the autonomous level of the robotic welding. A path planning method by visual servoing was presented, in which the optimal angle of charge-coupled device (CCD) camera was also planned. Aiming at planning two forms of kinked line seams, obtuse angle seam and right angle seam, a practicable solution was put forward. In this solution, the intersection of two adjacent straight segments is detected in each local seam image, and if intersection is found, the seam errors are calculated using the next straight segment. The experimental results show that kinked line seam can be well planned using this solution.     

Path Planning of Planar Kinked Line Seam by Visual Servoing for Robotic Welding

Welding path planning can substitute for the manual teaching process of the robot and can promote the autonomous level of the robotic welding. A path planning method by visual servoing was presented, in which the optimal angle of charge-coupled device (CCD) camera was also planned. Aiming at planning two forms of kinked line seams, obtuse angle seam and right angle seam, a practicable solution was put forward. In this solution, the intersection of two adjacent straight segments is detected in each local seam image, and if intersection is found, theseam errors are calculated using the next straight segment. The experimental results show that kinked line seam can be well planned using this solution.     

BNi-7钎料钎焊EGR冷却器芯子的焊接工艺研究

NOx（氮氧化物）是汽车尾气排放物中的主要污染物之一,而冷EGR（废气再循环）系统是降低NOx的最有效的办法之一。该系统中的关键部件之一为EGR冷却器。本文介绍了EGR冷却器芯子的真空钎焊工艺。试验表明,真空钎焊用于焊接EGR冷却器芯子,焊接生产率高,各项性能指标满足规范要求。     

履带板加热器消除焊接残余应力的试验研究

测试了履带板加热过程中温度沿钢板厚度方向的分布，并用小孔释放法测试了补焊试板在焊态、经履带板加热以及炉内加热后残余应力的分布．结果表明，履带板加热时所需加热时间较长，但温度沿试板厚度方向梯度小，截面温度分布均匀；履带板加热器消除焊接残余应力效果与炉内加热相当．     

Prediction of Welding Deformation of Underframe

IntroductionWelding deformation is a common and impor-tant problem in industry.In the last decades re-searchers have made efforts to predict and controlwelding deformation.There are usually three waysto determine the welding deformation:1 experi-ential formulas.2 Thermal elastic- plastic FEMmethod.3 Inherent strain method based onFEM[1～ 3 ] .Experiential formulas are only fit for simpleshape structures.Current thermal elastic- plasticmethod usually simulated either small or simplestructur…