Examination of weld defects by computed tomography

Defects in metal arc gas (MAG) welds made in S235JR low carbon steel of 6 mm thickness were examined. A sample containing lack of fusion (LOF) and pores was examined by computed tomography – CT. The computed tomography examination was performed in order to define LOF size and position as well as dimensions and distribution of accompanying pores in the weld metal

Ispitivanje grešaka zavara kompjutorskom tomografijom

Defects in metal arc gas (MAG) welds made in S235JR low carbon steel of 6 mm thickness were examined. A sample containing lack of fusion (LOF) and pores was examined by computed tomography – CT. The computed tomography examination was performed in order to define LOF size and position as well as dimensions and distribution of accompanying pores in the weld metal.Ispitivane su greške u zavarenom spoju niskougljičnog čelika S235JR debljine 6 mm zavarenog MAG postupkom. Uzorak koji sadrži greške naljepljivanja i pore je ispitivan kompjutorskom tomografijom - KT. Programskom analizom tomografa je određena veličina i pozicija grešaka naljepljivanja kao i dimenzije i raspored pratećih pora u zavarenom spoju

Fracture of drilling head pipe connection due to quenching of heat affected zone (HAZ)

The drilling head pipe connection is made of quenched and tempered steel 34CrNiMo6. The steel characteristic is high hardenability. Due to unsuitable and untested welding technology the heat affected zone (HAZ) cooling rate after welding surpassed the upper critical cooling rate. During horizontal drilling of the rock, the resulting brittle martensite could not bear the dynamic loads which led to a brittle fracture of the pipe connection

Reaktionen mit N-(1-Benzotriazolylcarbonyl)-aminosauren. I. Synthese von Hydantoinen und Hydantoinsaure-amiden

Die N-(1-Benzotriazolylcarbonyl)-aminosiiuren (I) werden mit Thionylchlorid in die mit der BTCO-gruppe geschutzten Aminosiiure- chloride (II) uberftihrt. Die konnen dann mit verschiedenen Aminen, indirekt uber isolierbare N-(1-Benzotriazolylcarbonyl)- aminosiiureamiden (III), oder direkt in die entsprechend substituierten Hydantoinsiiure-amide (IV) umgesetzt werden. Die Verbindungen III unterliegen bei der Einwirkung von Alkalien einer Cyclisierungs-Eliminierungs-Reaktion und liefern die 3,5-substituierte Hydantoine (V)

Metallurgical reactions in the coalescence zone between a reinforcement and a base metal in reinforced brazed joints

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising