1、本科生毕业论文 1 外文资料翻译 HISTORY OF UNDERWATER WELDING TECHNOLOGY Underwater welding technology is the development of the marine, offshore oil exploitation as well as assembly, maintenance such as oil platforms, pipelines and submarine positions in large marine structures such as one of the key technologies
2、, but also ships emergency repair, salvage, construction of bridges and other necessary technically work means. Nuclear power development is the trend of the world in nuclear power plants within the reactor pressure vessel (RPV) for long-term work in the water, susceptible to stress corrosion cracki
3、ng of the damage, structural repair of nuclear power, will face many challenges. To often use radiation-related underwater welding method, in order to reduce the working staff. Classification of underwater welding underwater welding generally divided into three categories: wet, dry, and local dry. A
4、nd the dry can be divided into high-pressure dry underwater welding and common-pressure underwater welding pressure. Local laws, including drainage cover dry type, high-pressure curtain-style, steel brush, mobile air box and plasma arc MIG local dry method. Welding method used generally coated elect
5、rode welding, GTAW, GMWA, and FCAW. In addition to welding underwater welding in addition there is an explosion welding and FSW (friction stitch welding friction stitch welding), these two methods are all connected by solid phase technology. Following the development of underwater welding course: 1
6、Underwater wet welding technology In 1802, a scholar named Humphrey pointed out that a continuous arc can burn under water, that pointed out the possibility of underwater welding, but its practical application is more than 100 years later, can not move the structure on land welding was done under th
7、e circumstances. In 1917, the British naval dockyard welders using underwater welding methods to block in the underwater part of ship rivets leaking cracks, this is the first application of underwater welding. The first published an article about underwater welding research papers in 1933, was joint
8、ly by Hibshrman Jensen and complete. 1932, Khrenov invented the thick skin of underwater medicine special electrode, the electrode surface top coat with waterproof layer, so that the stability of underwater welding arc has been improved to some extent. To the Second World War, underwater welding tec
9、hnology has been in the salvage boat, etc. play an important role. In 1971, Humble Oil Company of the Gulf of Mexico drilling platforms, underwater welding repair work is the first underwater welding technology used in offshore oil projects. 1985 produced the first batch of accredited diving welder,
10、 and developed a depth of less than 100m underwater wet welding. In 1987, underwater wet welding stainless steel piping in nuclear power plant has been applied to the repair work. 90s of last century, with the required repair of underwater engineering structures and the increase in the cost of incre
11、ased repair dock, wet welding technology has been further developed. The development of underwater welding underwater wet welding plays an important role in the application. British Hydroweld a variety of underwater welding company achieved good practical results. U.S. Patent electrode -7018 s drug
12、electrode layer of aluminum skin, underwater welding can produce large amounts of gas, to avoid the erosion of the weld metal. University of Hanover, Germany-based slag - gas combined protection of the metal transfer process and protective mechanism developed from the protection of double-cored elec
13、trodes. Underwater wet welding is usually the water depth of less than 100 m, the direction of current efforts is to achieve 200 m water depth of wet welding technology breakthrough. Early 50s of last century, underwater wet welding arc welding had been applied in our country. 60s of last century Ch
14、ina began developing its own dedicated underwater welding. South China University of Technology developed underwater welding rod available in 30 m water depth less than a good welding performance. 2 Underwater dry welding technology High dry underwater welding technology High-pressure dry underwater
15、 welding, the idea is first proposed in 1954 the United States, officially for the 1966 production, mainly used for submarine pipeline repair. The maximum current is about 300 m water depth in the. The welding method, the bottom chamber is open, and through the work of deep water into the air pressu
16、re slightly larger than the pressure of the gas, the indoor air discharge water from the bottom of the openings, welding gas chamber in the dry conducted. MIG welding or commonly used, is the underwater welded TIG welding quality, basically, one of the best ways to weld level can land. In the 1970s,
17、 no high pressure welding of equipment developed. Germany, Norway, the United States, Britain began in the late 90s no such research and the establishment of high-pressure welding research center. From the mid 80s of last century, a number of research centers began to study 300 500 m water depth GTA
18、W automatic welding systems and processes, or to test 500 1000 m water depth replacement of the adaptability of the welding technology. Now France, Germany, Norway, the United States, JEM hyperbaric welding research center operating pressure can reach the equivalent of 1000 m water depth. 90 years f
19、rom the last century, the operating oil companies have begun to enter the deeper waters. The first water depth in this company should be operating under the Brazilian oil company (that is, the Brazilian national oil company), its operations in the Amazon basin, and depth to 1000 m. In China, along w
20、ith the development of offshore oil industry, the urgent need to develop with independent intellectual property rights of high-pressure welding technology and dry. In the 2002 863 program in there on the high-pressure dry underwater welding technology research projects. By the China Offshore Oil Eng
21、ineering Corporation, Beijing Institute of Petrochemical Technology, Petroleum University, Shanghai Jiaotong University, Harbin Engineering University, the largest joint R&D Welding depth of 60 m. At present, the basic of the project has completed, the upcoming is sea trials. Dry underwater welding
22、technology at atmospheric pressure Dry underwater welding pressure welding quality although better, but its limitations more, especially with the increase of water depth, increasing air pressure around the arc, easy to destroy the stability of arc welding defect arising. Achieved in the absence of f
23、ully automated welding cases, the auxiliary diving welder operation, if the water depth exceeds the limit or dive diving high costs can not be implemented. In the technical level is unable to solve these problems, in order to overcome the deficiency of underwater dry welding, 1977, create underwater atmospheric dry welding equipment. In 1977, France LPS company first used this approach in the
