Research On Welding Automation And Flexible Production Technology Of Large Parts For Construction Machinery

With the rapid development of the world economy, all kinds of large mines and water conservancy projects continue to plan and construction, medium and small sized bulldozer has been unable to meet the requirements, the demand for large horsepower bulldozer is 50% per year growth rate of growth. Before the development of company of bulldozer, the domestic market 320 horsepower and above the bulldozer basically dominated by caterpillar, Komatsu, and other famous international brands. Large horsepower bulldozer machine and accessories are mainly dependent on imports, not only maintenance difficult, but also expensive, every year to spend a lot of foreign exchange in china. According to the market survey, the user is stable, the quality of the domestic large horsepower bulldozer is expected to become higher and higher. Shantui shares as domestic bulldozer manufacturing industry leader, has been continuously improved and perfect the core manufacturing technology, to create a SD32, SD42-3, SD52-5, SD90-5 such as large crawler bulldozer products, to achieve a large bulldozer localization. The increase of the power of SD42 and the power of high horsepower bulldozer is a great challenge to the manufacturing technology of large scale structure. Large scale structure of the main structure of the main frame, frame, and its own weight, the weight of its own large, long straight symmetric welding, welding, welding deformation is large and difficult to control. And the welding quality of these key structures has great influence on the performance and reliability of the whole machine. How to improve the welding quality and production efficiency of large structure parts is a difficult problem to be overcome. According to the long-term development planning and development needs of enterprises, the key issues of the large scale structure, which have a direct impact on the quality and efficiency of welding process, are studied. The main research content of this paper is as follows:In the process of gas shielded metal arc welding of large structures, a new technology of high speed welding for engineering machinery with high speed welding process was carried out with HD-Pulse pulse and no splash technology. The comprehensive properties of the weld metal were improved by a series of process experiments and test data analysis. CO2 gas shielded welding seam forming quality is poor, the welding rate is low (about 80%), the welding splash is big (about 13-15%), and the work load is big and so on. Through the analysis of the basic method of the welding fixture design and the related technology, especially the combination of fixture, flexible fixture and other related technology, according to the use and design characteristics of welding fixture, the welding fixture of large structure parts is analyzed. The new product development cycle, which is suitable for the development of new products, has greatly shortened the development cycle of new products, and reduces the cost of new product structure. The common welding machine types and application characteristics analysis of design for bulldozer bridge box structure characteristics of L type double rotary welding variable bit machine and matched with the welding industry and trade fixture. The welding positioner is open and wide, and it can be used for the welding of different types of bridge, the installation is convenient, the production efficiency is improved, the labor intensity is greatly reduced, and the welding quality is improved. Through the lean production management tools such as product, standard operation and other elements of analysis, draw the bridge box process schedule and process time histogram and the chart to find out the currently sd16 box bridge welding line model established in the process of bottle neck process, and to improve the analysis of the bottleneck, design a bulldozer Bridge box double wire welding robot scheme, and describes the main feature of double wire welding robot. Through the welding process of the part of the weld, the welding process of the double wire robot is performed, the bottleneck process is eliminated, and the target of the 36 SD16 rear axle box is realized.