The material flow and microstructural evolution in the friction stir welds of a 6061-Al alloy to itself and of a 6061-Al alloy to 2024-Al alloy plates of 12.7 mm in thickness were studied under different welding conditions. The results showed that plastic deformation, flow, and mechanical mixing of the material exhibit distinct asymmetry characteristics at both sides of the same and dissimilar ...

Automated ultrasonics is steadily becoming the standard method of inspection of pipeline girth welds throughout the world. In addition, old technology multiprobe systems are rapidly being replaced by newer phased arrays. Olympus NDT developed the first phased array system a decade ago, which proved to be much more flexible and capable than multiprobe systems, particularly for offshore special a...

Current robots spaces bifurcating blood vessels and Various machines navigation wheeled, caterpillar, wall and even snake also many caterpillar exploration Although devices lack adapting confinement. D to be con collapsed buildings, industrial and marine pipelines A relative invert of confinement. exploiting waves of muscular contractions that alternatively shorten and lengthen different portio...

Metagenomics literally means "beyond the genome." Marine microbial metagenomic databases presently comprise approximately 400 billion base pairs of DNA, only approximately 3% of that found in 1 ml of seawater. Very soon a trillion-base-pair sequence run will be feasible, so it is time to reflect on what we have learned from metagenomics. We review the impact of metagenomics on our understanding...

An experimental study was carried out to investigate seabed-pipeline interactions with regard soil liquefaction. For a high proportion (30 60%) of fine sediment, four groups tests were configured reproduce liquefaction around pipelines for different initial pipe depths, densities and wave conditions (wave height period). The focused on verifying the theoretically computed areas failure by analy...

Highly concentrated sediment flows may occur following failures of loosely compacted, granular slopes underwater or in waterfront areas. The mobility of such sediment flows is of considerable interest to the integrity of coastal fills, underwater pipelines and other such marine facilities. However, the physics of highly concentrated sediment-water mixtures is complex in nature and calls for mor...

Submarine pipelines are the lifelines of national economy. Under influence typhoons, high-speed currents and waves continuously erode seabed, leading to suspension or even rupture pipelines. Therefore, it is great importance study sediment transport under action currents. A numerical model scouring deposition combining wave established, which considered tidal current, storm surges, wind waves, ...

Welding of niobium and tantalum materials is currently conducted in vacuum or inert gas chambers, which limits the size of the equipment to be produced. The objective of this study is to investigate the means to make TIG welding on these materials in atmospheric environment and analyse the effect of heat input on the properties of welds. It was found that it is possible to make TIG welds on the...

Pathogenic microorganisms are able to adhere on equipment surfaces, being possible to contaminate food during processing. Salmonella spp. and Listeria monocytogenes are important pathogens that can be transmitted by food, causing severe foodborne diseases. Most surfaces of food processing industry are made of stainless steel joined by welds. However currently, there are few studies evaluating t...