Results 161 to 170 of about 4,897 (207)

Recent developments in underwater wet welding

Science and Technology of Welding and Joining, 2001
Developments in underwater wet welding processes over the past 25 years are reviewed. Shielded metal arc welding with rutile base coated electrodes is still by far the most common wet welding process in use. Research and development of wet welding electrodes has led to improvements in the control of hydrogen content, porosity, chemical composition ...
M. Rowe, S. Liu
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Explaining Porosity Formation in Underwater Wet Welds

Volume 4: Materials Technology; Ocean Engineering, 2007
Macroscopic porosity in underwater wet welds is one of the main defects that deteriorate the mechanical properties of the wet welded joints. It is well established that weld metal porosity is a function of pressure, thus water depth. However, the mechanism of porosity formation is not well understood, therefore the problem is not yet mitigated to ...
Faustino Pe´rez-Guerrero, Stephen Liu
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Underwater Wet Welding of Higher Strength Offshore Steels

Offshore Technology Conference, 1989
ABSTRACT The problems in underwater wet welding of higher strength steels are identified. Engineering fundamentals are being considered to guide future research to overcome some of the limitations to deep wet underwater welding of higher strength steels.
S. Ibarra, D.L. Olson, C.E. Grubbs
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Arc Stability Indexes Evaluation on Underwater Wet Welding

29th International Conference on Ocean, Offshore and Arctic Engineering: Volume 6, 2010
Underwater wet welding (UWW) with shielded metal arc welding (SMAW) is employed basically in repairs of offshore structures, including platforms, ships and others. The main problems of this type of welds are related, of course, with water presence in the electric arc that causes higher cooling rates, Oxygen and Hydrogen availability in the arc ...
Ezequiel C. P. Pessoa, Leandro F. Ribeiro, Alexandre Q. Bracarense, Weslley C. Dias, Luciano G. D. Andrade, Stephen Liu, Valter R. Santos, Mauri´cio J. Monteiro   +7 more
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Active Visual Sensor Based Weld Seam Tracking for Underwater Wet Welding

Advanced Materials Research, 2013
Weld automation is the development trend of underwater welding, and underwater weld seam tracking is one of the key technologies in weld automation. This paper used active visual sensor to automatically monitor the weld seam in underwater wet weld process, and image processing algorithms were developed to automatically obtain the weld torch deviation ...
Bo Chen, Chuan Bao Jia, Ji Cai Feng
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Comparison of Solidification Behavior Between Underwater Wet Welding and Dry Welding

Volume 3: Materials Technology; Jan Vugts Symposium on Design Methodology of Offshore Structures; Jo Pinkster Symposium on Second Order Wave Drift Forces on Floating Structures; Johan Wichers Symposium on Mooring of Floating Structures in Waves, 2011
The solidification substructure, both mode and size, has influence on the mechanical properties of weld joints. Controlling the solidification substructure by obtaining finer grains will generally result in enhancement of the weld joint quality and properties.
Faisal M. Al-Abbas, Tariq A. Al-Ghamdi, Stephen Liu   +2 more
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Multipass All Position "Wet" Welding - A New Underwater Tool

Offshore Technology Conference, 1972
Abstract Before 1970 underwater "wet" welding techniques were virtually unchanged after 20 years. All position multiphase welds were not being made and high strength steels could not be welded without cracking. Wet wilding?s role as an underwater tool was, except for minor or isolated cases, relegated to salvage and
C.E. Grubbs, O.W. Seth
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Efficiency evaluation of underwater wet welding processes

Blanking productions in mechanical engineering (press forging, foundry and other productions)
Productivity and coefficient of surfacing during wet underwater welding with coated electrodes and tamper-proof flux-cored wire in laboratory conditions are determined. In flux-cored wire welding, productivity is much more dependent on current than in manual welding.
G.N. Vostretsov, V.M. Karpov, V.O. Muktepavel   +2 more
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Influence of welding speed on weld pool dynamics and welding quality in underwater wet FCAW

Journal of Manufacturing Processes, 2020
Abstract The effects of welding speed on the molten pool dynamics, the weld forming and the diffusible hydrogen content in deposited metal during underwater wet flux cored arc welding (FCAW) were studied. The molten pool was elongated with a higher solidification speed, as the welding speed was increased.
Changsheng Xu, Ning Guo, Xin Zhang, Haiyue Jiang, Yanbo Tan, Li Zhou   +5 more
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Diffusible hydrogen in underwater wet welding

Welding in the world, 2008
The rapidly increasing development of the laying of high-strength steel underwater pipelines for the transportation of gas and oil requires adequate welding technology for maintenance and repair. As FCAW is suitable for automation and appropriate for application at greater depths it represents a welding process capable of replacing MMAW underwater wet ...
Kožuh, Zoran, Kralj, Slobodan, Garašić, Ivica   +2 more
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