Investigation of Friction Weldability of En Aw 6063 Aluminium Alloy Tube to Tube Plate Using an External Tool
The traditional welding methods are commonly used tube to tube plate of heat exchangers and economiser. In this study it was investigated that application of an alternative welding method which called friction welding of tube to tube plate by using an external tool was used joining of AlMg0,7Si (EN AW 6063) aluminium alloy. The AlMg0,7Si plates with dimensions 5x50x70 mm were drilled Ø20,5, Ø21, Ø21,5, Ø22 mm. The four different sizes AlMg0,7Si tubes with dimensions 2 mm wall thickness, 20 mm outer diameter, respectively 45,5, 46, 46,5, and 47 mm length friction welded to plate using an external tool (FWTPET) at constant 900 min-1 tool rotational speed. The vertical force between tool shoulder and tube was constant during the welding, and temperature was measured at every different welding parameters. The shear test was done for determining for welded joints using special fixture. Shear strength of welded joints were determined depend on welding parameters
Suitability of friction welding of tube to tube plate using an external tool process for different tube diameters—A study
During the past few decades, the field of welding technology has been witnessing tremendous challenges. Welding is an important metal fabrication process that has high potential for industrial applications. Friction welding is a vital solid state joining process that has gained popularity in welding non-weldable alloys. Friction welding of tube to tube plate using an external tool (FWTPET) is an innovative friction welding process and it was invented in the year 2006. FWTPET is capable of welding tube to tube plate of similar or dissimilar metals and is capable of producing good-quality leak-proof weld joints. In this work, four different tube diameter conditions in FWTPET welding have been studied. Macrostructural and microstructural studies have been conducted and they reveal the weld configuration that is susceptible to defect formation. Hardness and tensile strength of four different tube diameter preparations have been analyzed. The present study leads to the production of defect-free weld joints which have numerous industrial applications.
New records of Grania (Clitellata, Enchytraeidae) in the Northeast Atlantic (from Tromsø to the Canary Islands), with descriptions of seven new species
Previous northeast Atlantic records of Grania have been mainly from Germany, southern Scandinavia, and the Atlantic shores of France, Spain and Ireland. They were referred to eight species, with one, G. atlantica, reported from the continental slope. We have examined various unpublished collections from sources spanning from the Canary Islands to the Norwegian Arctic. Apart from new information on morphology, taxonomy, and distribution of known species, we describe seven new taxa (G. canaria, G. fortunata, G. mauretanica, G. aquitana, G. vikinga, G. torosa, and G. papillinasus). The collection of G. papillinasus from 2630-2885 m represents a new depth record for Enchytraeidae. Twenty-five of the now 57 Grania species occur in the North Atlantic. The North Atlantic drift moderates sea temperatures along the northeast Atlantic coasts, probably facilitating the wide latitudinal range of some taxa, as well as actual dispersal within the region. A "chaetal index" (chaetal length : chaetal foot length) is proposed to differentiate L-shaped chaetae at the species level. Complex relationships within the "type 6 group" of Grania suggest that groupings established using certain combinations of penial, chaetal and spermathecal patterns may not be monophyletic. For a better phylogenetic resolution, additional morphological details of these and other characters are needed.