自动焊接操作系统#中英文翻译#外文翻译匹配

An automated welding operation planning system for block assembly in shipbuilding Kyu-Kab Cho*, Jung-Guy Sun, Jung-Soo Oh Abstract The block assembly process is one of the most important manufacturing processes for shipbuilding. Since block is composed of several steel plates and steel sections with predetermined shapes according to ship design, the welding operation planning to construct a block is a critical activity for shipbuilding, but this activity has traditionally been experience based. Thus, it is required to develop an automated welding operation planning system to assemble blocks. This paper describes the development of an automated welding operation planning system for block assembly in shipbuilding. Based on the information about parts, topological relationship between parts and assembly sequences for block, the developed system performs the determination of welding postures, welding methods, welding equipment and welding materials. The developed system implemented successfully for real blocks constructed in shipyard. Keywords: Block assembly; Expert system; Operation planning; Welding process 1. Introduction Shipbuilding is traditionally a labor-intensive assembly industry that employs the welding process as a basic production technology. In shipbuilding, there are several types of manufacturing process planning for cutting and bending, assembly, out- fitting, and erection. Among these process planning activities, the assembly process planning is by far the most important, since the construction process for a hull block comprises approximately 4850% of the total shipbuilding process 1,2. The main operation for block assembly is the welding operation. The welding operation planning problems in block assembly are very difficult to solve because all blocks are different in size, type, and constituting sub-assemblies that depend on the types of ships. Also, since this activity has traditionally been experienced-based, welding operation planning in shipbuilding has been performed manually. Thus, it is very important to develop an automated welding operation planning system for shipbuilding. There is relatively very little literature available on automated welding operation planning systems for shipbuilding 3,4. This paper deals with the development of an automated welding operation planning system for block assembly in shipbuilding. The rule-based expert system for welding operations has been developed using Smart Elements as an expert system tool. The developed system is demonstrated and verified by using actual blocks in the shipyard. 2. Development of an automated welding operation planning system 2.1. System framework The automated welding operation planning system developed in this paper consists of four modules: welding postures module, welding methods module, welding equipment module, and welding materials module. The framework of this system is shown in Fig. 1. 2.2. Determination of welding postures This module determines the posture of the welding operator. Welding posture is reasoned by considering connection types and positional direction between two connected parts, direction information of assembly base part, existence of turnover, and assembly level. Connection types are classified into butt type (B) and fillet type (T), as shown in Fig. 2. The four types of welding postures, down posture (D), overhead posture (O), horizontal posture (H), and vertical posture (V), are considered in this paper, as shown in Fig. 2 5,6. The most stable and easiest welding posture is the down welding posture, and the most difficult one is the overhead welding posture. The welding operator determines an efficient welding posture according to the working conditions. For relationship of connection between two parts that are welded, one part is considered as the base and the other is connected to the base. The part that is considered as a base is represented as PartFrom and the other that is connected to the base is represented as PartTo. The levels of block assembly to assemble steel plates and sections into the final block are classified into subassembly (SA) level, unit block assembly (UBA) level, and final block assembly (FBA) level.Subassembly levels may be divided into small subassembly (SSA) levels and intermediate subassembly (ISA) levels according to the size and weight of the subassembly as shown in Fig. 3. For determining welding postures, the block assembly levels are classified into two groups. The first group is the small subassembly level; the second group consists of the intermediate subassembly, the unit block assembly, and the final block assembly levels. The reason for this grouping is that there is no turnover process in the small subassembly level, but the assembly levels belonging to the second group may have turnover processes. Turnover processes cause the change of welding postures that are determined before the turnover process. 2.2.1. Determining welding postures in the first group level The following are examples of rules to determine the welding posture for a small subassembly level. The connection types of welding joints between two parts used in this rule are: Butt type (0) and T type (1). (1) IF (Part Level=Small Assembly) (Connection Type=1) (Direction of Assembly Base=Connection Direction) (PartFrom=not Assembly Base Part) (PartTo=not Assembly Base Part) THEN (Welding Posture=H) (2) IF (Part Level=Small Assembly) (Connection Type=1) (Direction of Assembly Base Part=not Connection Direction) (PartFrom=not Assembly Base Part) (PartTo=not Assembly Base Part) THEN (Welding Posture=V) An example of a small subassembly is shown in Fig. 4. In this case, there are ve parts, and the assembly base parts are A and B. The relationships between the parts are listed in Table 1 and the results of the determination of welding postures for this example are shown in Table 2. 2.2.2. Determining welding postures in the second group levels In the second group levels, information for determining welding postures is the same as for the small subassembly level. Welding postures are determined between the assembly base part and other parts that are connected to the assembly base part in a similar way to the small subassembly. Other welding postures are determined between parts that are not an assembly base part. If turnover processes exist, the direction of the assembly base part is changed at an angle of 180 and the welding posture is also changed. An example of the rules for the second group levels are as follows: (1) IF (Part Level not Small Assembly) (Connection Type is 0) (Direction of Assembly Base Part Connection Direction) (PartFrom not Assembly Base Part) (PartTo not Assembly Base Part) THEN (Welding Posture H) (2) IF (Part Level not Small Assembly) (Connection Type 0) (Direction of Assembly Base Part not Connection Direction) (PartFrom not Assembly Base Part) (PartTo not Assembly Base Part) THEN (Welding Posture V) 2.3. Determination of welding methods This module determines the welding methods based on welding postures by rule-based reasoning. Welding methods used in this paper are summarized in Table 3, according to the connection types of welding joints and welding processes 7. In general, there are several welding techniques such as braze welding, forge welding, gas welding, resistance welding, induction welding, arc welding, and special welding. Considering the features of shipbuilding, the welding process used in the shipyard is the arc welding process. Arc welding is a process in which coalescence is obtained by heat produced from an electric arc between the work and an electrode 8. Arc welding is classified into several types, according to the welding mechanisms such as shield metal arc welding (SMAW), flux cored arc welding (FCAW), submerged arc welding (SAW), and electrogas arc welding (EGW). SMAW is one of the oldest, simplest, and most versatile joining processes. Currently, about 50% of most industrial and maintenance welding is performed by this process, but this process is used approximately less than 5% at most large shipyards. In FCAW, an electrode that is tubular in shape is used, and if necessary, the welding area is shielded by carbon dioxide. In SAW, the weld arc is shielded by granular flux, consisting of lime, silica, manganese oxide, calcium fluoride, and other materials. The flux is fed into the weld zone by gravity flow through a nozzle. EGW is used primarily for welding the edges of sections vertically in one pass, with the pieces placed edge to edge (butt type) 9. To build the knowledge base for the determination of welding methods, knowledge is aquired from welding handbooks and experts. Input information of this module is geometrical information that is provided from CAD system and the welding posture determined by welding posture determination module. The knowledge is represented by rules. The examples of the rule for the determination of welding methods are as follows: (1) IF (Connection Type=0) (Groove=none) (Welding Posture=O) (6 Thickness 50) THEN (Welding Method=SMAW-MANUAL BUTT) (2) IF (Connection Type=1) (Leg Length 4.5mm) (Welding Posture=O, H, V) THEN (Welding Method=FCAW-FILLET) 2.4. Determination of welding equipment This module selects the appropriate welding equipment by rule-based reasoning based on information about welding postures and welding methods. Table 4 shows the relationship between welding methods and welding equipment. After determining welding methods, welding equipment is automatically selected by using the information contained in Table 4. 2.5. Determination of welding materials This module determines the most proper welding materials by rule-based reasoning, based on information about welding postures, methods, and equipment. In general, steels used for block assembly are mild steels and high tensile steels. Mild steel is a rolled plate, the tensile strength of which is less than 50 kg f/mm2. High tensile steel is a low-carbon alloy steel, the tensile strength of which is more than 50 kg f/mm2 with a yield strength of more than 30 kg f/mm2. Mild steel has four grades: A, B, D, and E. High tensile steel has three grades: AH, DH, and EH 9. The following are examples of rules to determine welding materials. (1) IF (Welding Posture=D) (Welding Methods=FCAW FILLET) (Welding Equipment=LN-7 or LN-9) (Steel Grade=(Mild Steel A,B,D,E) Highten-sile Steel AH,DH) THEN (Welding Material=MX-200H) (2) (Welding Posture=D) (Welding Methods=SAW Bothside BUTT) (Welding Equipment=SW-41) (Steel Grade=Mild Steel A,B,D,E) THEN (Welding Material=L-8xs-707EF H-14XS705EF L-8XNSH52) 3. System implementation and discussions In order to demonstrate and to verify the automated welding operation planning system for block assembly, a block located at the upper deck part of crude oil carrier is examined. Fig. 5 shows the structure of an example block and Fig. 6 represents its hierarchical structure. An example final block shown in Fig. 5 has two unit blocks, one intermediate subassembly, 15 small subassemblies, and 169 component parts. The final welding operation planning for the unit block assembly level is shown in Fig. 7. The results are verified by an expert process planner and implemented by using actual blocks in an assembly shop. 4. Conclusion An automatic welding operation planning system consisting of four modules (welding postures, welding methods, welding equipment, and welding materials) is developed by using Smart Elements as an expert system tool. The developed system is verified by using actual block and implemented in a block assembly shop. Acknowledgements This work is supported by the research grant from Hyundai Heavy Industries Co., Ltd. References 1 H. Nakayama, Expert process planning system of CIM for shipbuilding, Proceedings of International Conference on Computer Applications in Shipbuilding, 1994, pp. 12.55 12.66. 2 Ship and Ocean Foundation, Research Report on Shipbuilding CIMS Pilot Model Development, Japan, 1991. 3 H.B. Cary, Summary of computer programs for welding engineering, Welding Journal 70 (1) (1991) 40 46. 4 D.M. Barborak, D.W. Dickinson, R.B. Madigan, PC-based expert system and their applications to welding, Welding Journal 70 (1) (1991) 29 38. 5 J. Weber et al., Welding expert focus on the future, Welding Journal 69(7) (1990) 37 46. 6 K.K. Cho et al., An automatic process planning system for block assembly in shipbuilding, Annals of the CIRP 45 (1) (1996) 41 44. 7 J. Gustafsson, M. Heinakari, Experiences with CIM in shipbuilding, Welding Journal 70 (3) (1991) 27 35. 8 B.H. Amstead et al., Manufacturing Processes, 8th ed., Wiley, New York, 1987, pp. 156157. 9 S. Kalpakjian, Manufacturing Engineering and Technology, 3rd, Addison-Wesley, Reading, MA, 1995, pp.862 870. 自动焊接操作系统 Kyu-Kab Cho*, Jung-Guy Sun, Jung-Soo Oh 摘要 ： 船舶建造的分组装配作业加工是 其 最重要的制造法 。 因为块由若干钢板块和型钢同预定形状按照船舶设计组成的，所以对船舶建造来说焊接操作计划构造块是一项关键任务，但是这个是以传统经验为基础的 ，因此，有必要研制一种自动焊接操作计划系统来组装块。这篇论文描述了船舶建造分组装配作业的自动焊接操作计划系统的发展。根据零件和装配次序的拓扑关系介绍部分，系统完成确定焊接位置，焊接方法，焊接设备和焊接材料。 系统成功地实现了船舶建造块的构造。 关键词： 分组装配作业；专家系统；操作计划；焊接过程 简 介 船舶建造 是传统的劳动强度大的组装工业，焊接是 其 基本生产技术。 在船舶建造中 ,存在几种类型切割 ,装配制造法。在这些工艺设计活动之中 ,装配工艺计划是最重要的 ,因为船体结构加工大约包含了船舶建造加工总数的 40%-50%。焊接操作是分组装配作业的主要操作。焊接操作规划问题在装配过程中是很难解决的，因为部件的大小 , 类型 ,以及组成的取决于船的类型的亚部件是不同。 同样地，因为这些活动是以传统经验为基础的，所以，焊接操作在船舶建造中是人工执行的。因此，在船舶建造中，研制自动焊接操作计划系统是非常重要的。对船舶建造，几乎没有自动焊接 操作计划系统的文献可以利用。这篇论文涉及船舶建造分组装配作业的自动焊接操作计划系统的研制。这种基于规则的将灵敏元件当做专家系统工具的焊接操作专家系统已经被研制出来了。 这个系统通过造船厂的实际的部件已经被证明和复核。 自动焊接操作 系统的发展 2.1. 系统框架 在此论文里自动焊接操作计划系统由焊接 位置 模数、焊接方法模数、焊接设备模数，并且焊接材料模数组成四模数。这个系统的框架将在图 1中展示。 2.2. 焊接 位置 的确定 模数决定焊工的焊接 位置 。考虑到两连接零件连接类型和位置，方向部件的方向信息 ，翻转的存在以及装配等级等因素，焊接 位置 是受影响的。连接类型被分为对接和角接类型，如图所示。 这篇论文考虑了四种焊接 位置 :向下焊接，水平焊接，垂直焊接和仰焊接， 如图所示 。最稳定的和轻松的焊接 位置 是下向焊 位置 ，最困难的是仰焊 位置 。根据工作条件焊工决定采用一种有效的焊接 位置 。两焊接部的连接的关系，一个部分被认为是基体，而另一个被认为是连接在这个基体上。 被认为是基体的部分被当做 partfrom而连接到基体的部分被当做 PartTo。 装配钢板和型钢变成最后的部件的分组装配作业水平被分为组件水平（ SA），单元块组装水 平（ UBA）和最后的分组装配作业水平（ FBA）。根据组件的尺寸和重量组件水平可以被分成小组件水平（ SSA）和中间的组件水平（ ISA）如图所示。 因为决定焊接 位置 ,分组装配作业水平被分为组。第一个组是小部件水平；第二组由中间部件组成，为单元块组装和最后的分组装配作业水平。 这样分组的理由是看是否有翻转的加工小部件，但是装配水平属于第二组的也许也有翻转加工。翻转加工之前的决定产生致使焊接 位置 发生变化。 2.2.1. 决定焊接 位置 的第一组 水平 以下用来决定焊接 位置 的规则适合于小部件水平。用于此规则焊接接 头的连接类型是：对接式（ 0）和 T类型（ 1）。 (1) IF (Part Level=Small Assembly) (Connection Type=1) (Direction of Assembly Base=Connection Direction) (PartFrom=not Assembly Base Part) (PartTo=not Assembly Base Part) THEN (Welding Posture=H) (2) IF (Part Level=SmallAssembly) (Connection Type=1) (Direction of Assembly Base Part=not Connection Direction) (PartFrom=not Assembly Base Part) (PartTo=not Assembly Base Part) THEN (Welding Posture=V) 小部件的例子在图 中列出。这里有五部分 ， 部件基体部分是 A和 B。这些部分之间的关系在表格 1中列出，这些例子确定焊接 位置 的结果将在表格中列出。 2.2.2. 决定焊接 位置 的第二组类水平 在第二组类水平 , 决定焊接 位置 的情况同小部件水平是一样的。 其他的焊接 位置 取决于非部件基体间的部件。如果存在翻转加工，部件基体的方向是以 180的角度变化，焊接 位置 也同样地变化。 适合于第二组类水平的例子规则的如下： (1) IF (Part Level=not SmallAssembly) (Connection Type is 0) (Direction of Assembly Base Part=Connection Direction) (PartFrom=not Assembly Base Part) (PartTo=not Assembly Base Part) THEN (Welding Posture=H) (2) IF (Part Level=not SmallAssembly) (Connection Type=0) (Direction of Assembly Base Part=not Connection Direction) (PartFrom=not Assembly Base Part) (PartTo=not Assembly Base Part) THEN (Welding Posture=V) 2.3. 焊接方法的确定 按规则根据焊接 位置 此模数决定焊接方法。根据焊接接头的连接类型和焊接过程7，此论文中使用的焊接方法被归纳于表格中。 通常 ,有若干焊接技术比如钎焊、压力焊、气保焊、电阻焊接、感应焊接、电弧焊以及特种焊接。考虑船舶建造的特色，被用于这造船厂的焊接方法是电弧焊接法。 电弧焊是由工件和电极间电弧产生的热而获得的接合法。 电弧焊根据焊接机构被分为若干类型，例如保护金属极电弧焊（ SMAW），药芯焊丝电弧焊（ FCAW），埋弧焊（ SAW）和气体保护电弧 焊（ EGW）。 保护金属极电弧焊是其中最老的，最简单的，最灵活多变的焊接方法。目前大约 50的工业焊接采用这种方法，但是在大多数造船厂中这种加工方法的使用大约小于 5%。在药芯焊丝电弧焊，在外形上管状电极是使用的，必要时，焊缝横截面面积被二氧化碳保护。在埋弧焊，焊接电弧被由石灰、硅石、氧化锰、氟化钙及其他材料组成的颗粒状熔剂遮挡。焊剂是靠重力流过焊缝进入焊接区的。 气体保护焊主要适合于焊接型钢的边缘，（对接式） 9。 建立这一知识库适合于焊接方法的确定。知识库数据是从焊接手册和专家取得。此模数的输入信息是由 CAD系统和焊接位置提供的几何信息，焊接位置由焊接位置确定模数确定。数据由准则代替。确定焊接方法的准则例子如下： (1) IF (Connection Type=0) (Groove=none) (Welding Posture=O) (6 Thickness t 50) THEN (Welding Method=SMAW-MANUAL-BUTT) (2) IF (Connection Type=1) (Leg Length 4.5mm) (Welding Posture=O, H, V) THEN (Welding Method=FCAW-FILLET) 2.4. 焊接设备的确定 此模数按规则，根据有关焊接位置和焊接方法的信息选择适当的焊接设备。表格显示焊接方法和焊接设备之间的关系。利用表格 4列举的情况，在确定焊接方法后，焊接设备被自动地选择。 2.5. 焊接材料的确定 根据焊接位置、方法和设备的有关情况，此模数按规则确定最适当的焊接材料。通常、被用来作分组装配作业的钢材是低碳钢和高强度钢。 低碳钢是轧制钢板，其抗拉强度小于 50 kg f / mm2。高强度钢是低碳合金钢、其抗拉的强度大于 50 kg