Welding technology development trend

 Development trend of welding technology

Welding technology is an operation method that uses welding materials (electrodes or welding wires) to connect two or more base metals (workpieces to be welded) into a whole under high temperature or high pressure conditions. As a traditional basic process and technology in the manufacturing industry, welding technology has not been applied to the industry for a long time, but it has developed rapidly. In just a few decades, welding has been widely used in many important industrial fields such as aerospace, automobiles, bridges, high-rise buildings, shipbuilding and marine drilling, and has made important contributions to promoting the economic development of industry, making welding an important professional discipline of manufacturing technology and material science. With the continuous development and progress of industry and science and technology, the development trend of welding technology presents the following characteristics:

(1) Improving welding productivity is an important driving force to promote the development of welding technology

Joining simple components and manufacturing blanks were the original welding methods, and with the continuous update of technology, welding has become an irreplaceable basic process in the manufacturing industry and a means of production for the production of precisely sized finished products. At present, the most important thing for welding technology is to effectively ensure the stability of welding product quality and improve labor production efficiency. There are two ways to improve productivity: first, improve the welding deposition rate, iron powder electrode, gravity electrode, lying electrode and other processes in electrode arc welding and multifilament welding and hot wire welding in submerged arc welding are all of this type, and their effects are remarkable. Second, reduce the groove section and the amount of deposition metal, among which narrow gap welding effect is the most significant. Narrow gap welding is based on gas shielded welding, using single, double or triple wire. Regardless of the thickness of the joint, the butt type can be used, and the amount of deposition metal required is reduced several times or dozens of times, which greatly increases productivity. The key to narrow gap welding is to ensure that the two sides are melted and the arc center is automatically tracked on the groove centerline. In order to solve these two problems, countries around the world have developed a variety of different solutions, resulting in a variety of narrow gap welding methods. The advanced nature of welding methods will be rated higher if progress can be made in improving deposition speed, reducing production cycles, improving process control, reducing repair rates, reducing joint preparation time, avoiding welders working in hazardous areas, reducing weld size, reducing post-weld operations, improving operating factors, reducing potential safety risks, and simplifying equipment setup. Efficient, fast and high-quality welding methods will become the main force.

(2) The welding process is automated and intelligent

Foreign welding technology develops rapidly, and there is a big gap in the development of domestic welding technology. The level of welding mechanization and automation rate in industrialized countries, increased from 19.6% in 1996 to more than 70-80% in 20xx, at present, welding technology and modern manufacturing technology, welding science and engineering, welding automation and welding robots continue to integrate, welding technology has been developed in the direction of automation and intelligence. Welding process automation, intelligence to improve welding quality stability, promote welding automation process, learning, absorption, reference, improvement is a very important link, should strengthen the learning and improvement of the existing process. However, most of China's current processes are manual operations, which have certain limitations. At present, the automation rate of welding in China is less than 30%, relatively speaking, the mechanization and automation level of welding production is very low, but if you can use modern automation technology for grafting transformation on the basis of learning, you can often achieve certain breakthroughs.Since the 90s of the 20th century, China has gradually promoted gas shielded welding in various industries to replace the traditional manual arc welding, and has now achieved certain results. At present, China has made great progress in welding production automation, intelligent process control, research and development of welding production lines and flexible manufacturing technology, development and application of computer-aided design and manufacturing technology. The development of computer technology, control theory, artificial intelligence, electronic technology and robot technology provides a very favorable technical basis for welding process automation, and has penetrated into various fields of welding, and has achieved many results, welding process automation has become one of the growth points of welding technology. The intelligence of welding process control system is one of the core problems of welding automation, and it is also an important direction for our future research.

(3) Research and development of heat sources

The heat source is the energy source that provides heat energy to enable the basic welding process, and the heat source is moving. In the welding process, the heat source conducts heat energy by means of heat transfer at points, lines, surfaces, etc. The welding heat source is characterized by a high concentration of energy density, a fast realization of the welding process, a guaranteed high quality of the weld seam and a minimum welding heat affected zone. At present, welding heat sources have been very abundant, such as arc welding, chemical heat, resistance heat, high-frequency induction heat, friction heat, electron beam, plasma flame, laser beam, etc. The research and development of welding heat source has always continued, and the development of new welding heat source will promote the development of welding process and promote the generation of new welding methods. Every time a new heat source appears, it is accompanied by a batch of new welding methods. The welding process has successfully used various heat sources to form a corresponding welding method. Future development will proceed from improving existing heat sources to make them more useful, convenient and cost-effective and developing new and more efficient heat sources. Improving the existing heat source and improving efficiency, such as expanding the energy of the laser, effectively using the electron beam energy, improving the performance of the welding machine, and improving the energy utilization rate have achieved good results. Develop better and more useful heat sources, using two heat sources superimposed to achieve stronger energy density, such as participating in laser beams in electron beam welding.

(4) Energy-saving technology

With the development of society, energy conservation has become the primary consideration of all walks of life, and the welding industry is no exception. The development of energy-saving and environmentally friendly welding in the welding industry has become an inevitable trend; At the same time, the application of efficient welding process is of great significance to improve welding efficiency and save energy consumption. In order to meet the requirements of saving and environmental protection, hand arc welding machine and ordinary thyristor welding machine are gradually replaced by intelligent inverter welding with high efficiency and energy saving and automatic adjustment of parameters, and in order to adapt to the trend of diluting operation skills today, welding operations are gradually becoming intelligent and simple. Such energy-saving, environmentally friendly and high-efficiency technologies are more and more widely used in welding production.

(5) New materials, new technology development

Materials, as the pillars of the 21st century, have shown several changes in trends, namely from ferrous metals to non-ferrous metals; Change from metallic materials to non-metallic materials, from structural materials to functional materials, from multi-dimensional materials to low-dimensional materials; From a single material to a composite material, the connection of new materials will inevitably put forward higher requirements for welding technology. The emergence of new materials has become an important driving force for the development of welding technology, and many new materials, such as heat-resistant alloys, titanium alloys, ceramics, etc., have raised new topics. Especially the connection between dissimilar materials, using the usual welding method, has been unable to complete, the superiority of solid-state connection is increasingly apparent, diffusion welding and friction welding has become a hot spot in the welding industry, such as metals and ceramics have been able to diffuse connection, which was unimaginable before, so solid-state connection is a connection technology that will have a major development in the 21st century. The development of new industries has forced welding technology to move forward, and the introduction of new welding technologies more quickly can improve product quality and performance. Any important new technology and new method (such as STT, CMT, Cold Arc, etc.) is related to the welding process. This shows that the focus of technical competition of inverter welding machine products has begun to shift from power supply technology and control technology to welding process performance. MIG/MAG gas shielded welding gradually replaces manual arc welding will become the mainstream of welding, inverter welding machine, intelligent robot, vibration welding technology, laser composite welding and low-stress deformation free welding new technology - LSND welding method, etc., these energy-saving, environmentally friendly and efficient technologies are widely used in welding.

(6) Mechanization, the level of automation is improved

In order to complete the welding work well, it is necessary to fully prepare the work, including the welder's personal business familiarity, workpiece preparation and welding equipment preparation. Therefore, people have gradually paid attention to the placement workshop of welding equipment (welding machine), that is, the transformation of the preparation workshop. Improving the mechanization and automation level of the preparation workshop is the key development direction of the world's advanced industrial countries. For example, the use of microelectronics technology to transform traditional welding process equipment is the fundamental way to improve the level of welding automation. CNC technology is equipped with various welding machinery and equipment to improve its flexibility level; The combination of welding robot and expert system realizes automatic path planning, automatic trajectory correction, automatic control of penetration and other functions. Simply put, it is digital control: make "rough work" into "fine work, happy work".

Since its birth, welding technology has been influenced and guided by the latest development of many disciplines, under the influence of new materials and information science and technology, dozens of new welding processes have emerged, and the welding process is transitioning from manual welding to automatic welding and intelligence. The demand for welding technology progress is formed under the influence of economic and social factors, which significantly promotes the development of efficient materials and equipment and the application of automation technology, large-scale production and specialized production to create a new situation, efficient fast and high-quality welding methods have become the main force, a clear trend is to use more advanced control and monitoring technology in the traditional welding process. The introduction of new welding methods and advanced material technologies has improved the level of welding technology, but also posed new challenges. Foreign experts believe that welding, as a precise, reliable, low-cost and high-tech method of joining materials, will still be an important processing technology in the manufacturing industry by 20xx.