Application and Upgrading of On-line Monitoring System for Measurement and Processing of Electric Signals at Arc Stud Welding Process
As the application of on-line monitoring system is shown to be a good solution during monitoring of main welding parameters at different welding processes, this paper describes application and upgrade of on-line monitoring system developed at Mechanical Engineering Faculty in Slavonski Brod. Experimental part of the paper shows application of on-line monitoring system during welding of two types of studs with application of activating flux for ATIG process (VS-2E) on the base metal surface. Monitoring of main welding parameters (welding current and voltage) was conducted during welding of studs usually used in steam boiler production (stud diameter: 10 mm), and welding voltage was monitored on the studs (shear stud) of 22 mm diameters used in bridge construction. The goal of monitoring and analyse of main welding parameters is to evaluate the connection of electric arc parameters variations with the presence of activating flux.
Welding parameter monitoring during stud arc welding
The application of stud arc welding process is well known in various manufacturing fields and civil engineering due to simplicity of application, short welding time and cost efficiency. In this paper, application of on-line monitoring of main welding parameters (welding current and voltage) is used in the examination of process stability during stud arc welding with ceramic ferrule. The goal of this experimental work is to make the best choice of monitored welding parameter to assure the high quality of arc stud weld joint. So, the applicability of stability evaluation methods usually used in MAG (Metal Active Gas) welding process is analyzed for stud arc welding application. The connection between stability of stud arc welding process and weld quality is evaluated through macro section analysis of the welded joints.
A new genus and species of Thyasiridae (Mollusca, Bivalvia) from deep-water, Beaufort Sea, northern Alaska
Abstract Bivalve mollusk shells were collected in 2350 m depth in the Beaufort Sea, Arctic Ocean off northern Alaska. Initial identification suggested the specimens were a member of the bivalve family Thyasiridae, but no known eastern Pacific or Arctic living or fossil thyasirid resembled these deep-water specimens. Comparisons were made with the type of the genera Maorithyas Fleming, 1950, Spinaxinus Oliver & Holmes, 2006, Axinus Sowerby, 1821, and Parathyasira Iredale, 1930. We determined the Beaufort Sea species represents a new genus, herein described as Wallerconcha. These specimens also represent a new species, herein named Wallerconcha sarae. These new taxa are compared with known modern and fossil genera and species of thyasirds.