At present, China has become the world's largest welding materials producer, output has reached more than 120 million tons, the product structure is still dominated by low-grade ordinary electrode, high efficiency and high-tech welding a smaller proportion of the product . China's welding industry and industrialized countries the gap between yields on longer, but in the overall quality and level of scientific research, including the quality of personnel, production equipment, detection technology and research and product development.
In recent years, welding materials, product structure has also undergone a change, the overall trend is welding production by the year increased to stable and a decreasing trend, welding (including gas-shielded welding wire and submerged arc welding wire), agglomerated flux production is increased year by year, welding materials, production growth to slow from the fast, general-purpose Welding Electrode Suppliers materials, the degree of concentration of production gradually increased, to keep the focus on large enterprises, small businesses are looking for specialty products and market-specific business. In 2001, China's production of welding materials, with Figure 1.
A production of welding materials
1.1 welding
Electrode manufacturer in China at present there are about more than 400, which have the best production conditions, detection methods and reasonable quality assurance system of about 250, with a certain production conditions, the lack of testing means nearly 150, the industry's production capacity of about 1.5 million t, far beyond the needs of the market. Welding production company located in all regions except Tibet, under the machinery, metallurgy, energy, shipbuilding, agriculture and other sectors, the economic types of state-owned, collective, private, joint venture, sole proprietorship, joint-stock.
Welding industry has experienced the benefits of the peak period of 1992-1993, due to the sharp increase in production enterprises, resulting in rapid increase in production capacity, production continues to increase, resulting in declining prices of common products, electrodes significantly reduced to no profit margins or loss. Currently, except for a few scale, multi-industry development of special welding rod (refer to low-hydrogen electrodes, stainless steel welding rod, welding electrode, nickel-based electrodes, cast iron welding electrodes and other special purpose) operating characteristics of the enterprises to maintain a certain profit, the other major Some enterprises in the preservation or loss of state. The production of ordinary carbon steel electrode increasingly concentrated in a few large manufacturers of welding consumables.
The face of fierce market competition, small and medium enterprises are active in reducing the cost of raw materials and energy consumption costs to maintain operations, which bring a number of product quality in a certain degree of decline, the larger companies in addition to use of scale, strengthen the management to improve the technological level of other means to reduce production costs other than Flux Core Welding Wire, but also actively adjust the product structure, expand welding wire, flux, or other industries, in order to improve market competitiveness, and actively explore foreign markets. In 2001 production of various types of welding electrodes, shown in Figure 2.
1.2 Wire
1.2.1 Gas-shielded solid wire
Currently, the country's gas protection welding wire more than 150 manufacturing enterprises, from Germany, Sweden, Canada, Sweden, Italy and China Taiwan region to introduce a variety of production equipment 50 sets, made or developed by more than 100 sets of equipment, production capacity of more than 20 million tons, mainly by state-owned, collective, private, joint ventures and wholly owned enterprises, and other major wire rod production plant has become the backbone of business.
In recent years, the majority of enterprises in key technology breakthrough has been made, so the producers are increasing production of gas-shielded welding equipment and production, but because of metallurgical aspects, less gas-shielded welding wire varieties, in addition to ER49 Type-1 and ER50-6 production of larger, most of the remaining species a smaller yield.
1.2.2 Gas shielded flux cored wire
In recent years, flux-cored wire production has been substantial development, from more than 500 tons in 1996 to 2001, the development of about 1.2 million t, there are already 28 (including three foreign-funded enterprises), a total of 39 production lines, including the introduction of production line 21, made with 18 production lines, production capacity of existing equipment up to 2 million tons, annual output of more than 1000t of companies now have four. 1996-2001 the number of domestic flux cored wire, shown in Figure 3, the market usage, shown in Figure 4.
1.2.3 Submerged Arc Welding Wire
Currently, companies can supply hundreds of submerged arc welding wire, some companies can discoid supply, because in addition to single-electrode submerged arc welding process, but has grown to a multi-electrode and multi-standard wire, etc., makes the application of volume submerged arc welding wire increased in recent years, the production of copper wire submerged arc welding an increasing number. Carbon dioxide in 2001 to protect domestic production of solid welding wire of 14 million t, flux-cored wire of about 12,000 t, submerged arc welding wire of about 50,000 t.
1.3 SAW agent
Flux manufacturers in China have more than 30 industries throughout the flux t annual production capacity of about 150,000, of which melting flux 11-12 million t, agglomerated flux 3-4 million t. Currently able to produce agglomerated flux of more than ten enterprises. In recent years, expanding the market agglomerated flux, agglomerated flux in the flux in the percentage continues to increase. Domestic production of SAW agents in 2001 about 7 million tons, of which about 5 million tons of flux melting, sintering flux nearly 2 million tons.
2 welding Material application trends
Fabricated metal products are related to the modern welding applications in the petrochemical equipment industry (such as heat exchangers, pressure vessels, tanks, etc.), vehicle manufacturing (such as ships, rail vehicles, automobiles, aircraft, etc.), machinery manufacturing (such as industrial machinery, equipment, etc.) boilers, bridges and the construction industry and other industries with welding materials industry has great relevance. Welding materials industry and the rise and fall of these industries are closely related.
(1) shipbuilding. China's shipbuilding system has been proposed that by 2005 all major shipyard welding efficient rate to 80%, of which carbon dioxide gas shielded arc welding application rate of 55%, welding mechanization and automation rate of 70%.
Shipbuilding industry through the "85", "95" years to promote the efficient welding technology, industry-wide use in gas shielded arc welding and flux cored wire submerged arc welding technology. With the internationalization process of China's shipbuilding industry development, the efficiency of the welding material, craft, and so the amount of dust and a higher requirement.
(2) bridges and buildings
Is in transition from manual to semi-automatic welding, automatic welding process of change, a bridge built with low-carbon low alloy solid wire, cored wire will be greater development. Manual welding and submerged arc welding material will still maintain a certain ratio.
(3) semi-auto and rail vehicles, the proportion of automatic welding applications is growing rapidly, for MAG welding and submerged arc welding wire demand will increase.
(4) high-pressure vessels and storage tanks of various welding processes, different varieties of wire (such as carbon dioxide gas shielded solid wire, flux-cored and submerged arc welding wire) will have certain needs.
In short, the trend is the application of welding materials, high efficiency, high quality, suitable for use of automatic welding consumables will gradually increase, while other welding materials, especially low-quality welding consumables usage gradually decreased.
3 trends in welding materials and recommendations
3.1 "15" during the development trend of welding materials
3.1.1 welding
As the ordinary low-cost production of electrode has been close to the limit, the future of this rod production will be reduced gradually, and electrodes will be to adjust the product structure, special electrodes (referring to low hydrogen, heat-resistant steel, stainless steel, nickel-based and welding electrodes, etc.), the ratio will increase, electrode production will remain unchanged, but its share of the welding material from the current gradually decreased almost 80% to 70% or less.
3.1.2 Wire
(1) gas shielded solid wire
Although very few varieties of gas shielded solid wire, able to provide to the market mainly ER49-1 and ER50-6 two products, but its demand is increasing year by year with the production, the production ratio of the total welding consumables will gradually rise to about 18%.
(2) flux cored wire
Flux-cored wire production growth rates in 1996-2000, is currently the largest domestic gas production to protect carbon steel flux cored wire, flux-cored future varieties will increase rapidly, solid wire can not meet the low-temperature steel, weathering steel, resistant to hot steel, seawater corrosion-resistant steel and high strength structural steel with flux-cored welding wire to be filled, the other for oil and gas pipelines self-shielded flux cored wire welding and the surface restoration industry, with the flux-cored wire surfacing products will continue to development, which "15" period, the proportion of flux-cored welding consumables total will increase to 4%.
(3) the proportion of submerged arc welding wires submerged arc welding wire there will be no major change in the proportion of our submerged arc welding wire will remain at 10% -13%.
3.1.3 Flux
Submerged arc welding and submerged arc welding wire as agents, but also to maintain a certain production in the range of fluctuations, there will be no major increase, but the SAW agent will be some changes in the structure. "15" period, the total dose in the submerged arc welding, sintering flux ratio will increase, while the melting flux ratio will decline.
3.2 Welding materials development proposals
(1) large-scale enterprises to speed up welding material adjustment of product structure and product upgrading. Retention of large enterprises in general welding consumables based on the advantages of scale, should be automated welding direction, such as carbon dioxide, solid wire, cored wire, submerged arc welding wire, agglomerated flux, aluminum wire and so on.
(2), the characteristics of products to small businesses, market-specific management direction. Development of specialty products and niche markets, helps companies focus on human resources, geographical advantages, low-grade welding materials on the market to avoid price wars.
(3) to increase research and development investment, improve the quality of old products, develop new high-tech products. Improve the quality of old products is mainly to reduce dust and splash, all-position welding to improve welding performance, improved slag removal. Development of new high-tech products, including the development of non-copper solid wire, cored high efficiency Metal-cored, self-shielded flux cored wire, a large heat input submerged arc welding wire, low smoke electrode, Cr-Mo steel and duplex steel with electrodes, cellulose and vertical down low hydrogen all position electrode and high-strength steel with welding consumables.
(4) organization in the industry to promote, strengthen technological exchanges and cooperation. Welding industry organizations should play the coordinating role of industry organizations, to promote the production of welding materials and between enterprises and of raw materials, production of communication and cooperation between enterprises, and promote the progress of welding materials industry.
High strength steel with low hydrogen and high toughness flux cored Aluminium Welding Wireflux cored process, while the mineral composition
of the cored high-temperature dehydration, desulfurization, low melting point component of its package, so that the flux-
cored wire for the shield on the environment moisture wire in the welding process to maintain a low hydrogen content, and
only consider the general flux-cored Welding Wirecored high temperature baking water, which crack and anti-stomatal. The
treatment process has been successfully used for the construction of a number of high-strength steel hull, and in the field of
energy engineering and construction, significant economic benefits.