Electric welding

V.A. Troitskij, E.A. Davidov - E.O. Eaton Electric Welding Inst., Ukraine. 

Six certification centres are functioning in Ukraine at present in Kiev, Khar kov, Dmepropetrovsk, Zaporozhje, L vov and Ivano-Frankovsk The best known of them is the NDT Certification Centre at the E O.Paton Electric Welding Institute, which was the first one to receive, already in 1990, the licence of the USSR National Certification Committee for certification of the NDT experts. These certification centres have the right to grant levels I and II (according to EN 473), while level III can only be granted by the National Certification Committee. 

In 1981-1985 the Electric Welding Institute annually published the collections on the Development of NDT methods and means. ... 

Casing and liners shall be seamless or electric welded as defined below and as specified on the purchase. 

Operations such as gas or electric welding and cutting with cutting torches cannot be safely performed on hydrogen gas pipelines, mains, or auxiliary equipment, unless all possibility of leakage of hydrogen into the work area is eliminated. The following procedures are recommended ... 

Polymers are organic materials and are sensitive to natural or artificial UV sources. This is of primary importance for outdoor exposure of unprotected parts and for some industrial applications such as electrical welding, photocopier light exposure devices. .. 

Stray electrical currents from faulty equipment, improperly applied electric welding leads, or other sources... 

Stray-current Corrosion. Stray currents in the past have resulted from DC-powered trolled systems, which have become obsolete. An electric welding machine on board a ship with a grounded DC line located on shore will cause accelerated attack of the ship s hull as the stray currents generated at the welding electrodes pass out of the ship s hull through the water back to the shore. Houses in close proximity can dramatically corrode at the waterline. The pipes in one house can be completely corroded, while those in the neighboring house may be intact. 

At points where the current enters the structure, the site will become cathodic in nature because of changes in potential, while the area where the current leaves the metal will become anodic. Electric railways, cathodic protection, electrical welding machines, and grounded DC electrical sources are subject to stray current corrosion. (Craig)5... 

Eskin, G.I., Pimenov, Yu.P., Belova, M.V. et al. Room Temperature and Cryogenic Properties of Rolled Semis and Welded Joints Producedfrom 1201 Alloy Cast Billet with Nondendritic Structure. Abstr. 14th Int. Cryogen. Mater. Conf., June 1992, Kiev, Paton Electr. Weld. Inst., Kiev, 1992, p. 81. 

E.O.Paton Electric Welding Institute, ASTC Antonov... 

Wu W, Zhang Y, Zhang F, et al. 1996. [Studies on the semen quality in workers exposed to manganese and electric welding]. Chin J Prev Med 30 266-268. (Chinese)... 

Electric weld or submerged arc weld Grade A. Open hearth, electric furnace or basic oxygen. Electric resistance weld or submerged arc weld, double side. Not required... 

International Center for Electron Beam Technologies of E.O.Eaton Electric Welding Institute, National Academy of Science of Ukraine, 68 Gorky St. Kiev-150, 03150, Ukraine... 

CGA P-1, 3.3.2 4.5.13.1 When used in conjunction with electric welding, compressed gas cylinders shall not be grounded or used for grounding. 

For thin plates (thickness < 3 mm) electrically welded with a single pass, the problem is avoided because of the short time at critical temperatures. This makes electric arc welding favourable compared with gas welding [7.1]. 

The development of the process would not have been possible without making significant improvements in the hardware (7). Electrical welding was introduced a decade after the Burton process. Thus, the first stills had to be constructed of riveted steel plates, and they frequently burst at the seams. They also tended to leak at the seams and the escaping vapors would ignite fortunately the coke deposits that formed with time on-stream tended to plug the leaks as the still was used. Pumps that could handle hot oil safely were still to be developed. 

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