AWS A 5.1 electrode specification for SMAW

Specification for Carbon Steel Electrodes for Shielded Metal Arc Welding (SMAW) AWS A5.1 – A5.5

AWS electrode specification for SMAW Welding electrodes (welding rod) also called Shielded Metal Arc Welding (SMAW) welding rod which an electrode is a metal wire that is coated. It is made out of materials with a similar composition to the metal being welded. There are a variety of factors that go into choosing the right electrode for each project. SMAW or stick electrodes are consumable, meaning they become part of the weld, while TIG electrodes are non-consumable as they do not melt and become part of the weld, requiring the use of a welding rod. The MIG welding electrode is a[…]

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essential variables and nonessential variables

Essential Variables, nonessential variables and Supplementary Essential Variables in WPS

What is essential variable? Many variables and parameters affect welding quality such as such as such as joint details, base metals, filler metals, positions, preheat, PWHT. These parameters are known as WELDING VARIABLES (QG-105 & QW-250). All these variables are mentioned in WPS – Welding Procedure Specification so a welder or welding operator can develop good quality welding. In production, we have limitations, welding results can not be examined thoroughly. Some welding defects, can be seen visually by the Visual Welding inspector such as CSWIP 3.0 Welding Inspector. However strength, ductility and corrosion resistance can only be checked using destructive[…]

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types of welding techniques

types of welding techniques and process

what are the 4 types of welding? A piece of mechanical equipment (pipeline, tank, pressure vessel) is a collection of several metal components which are joined together into one equipment. Based on mechanism, the  joining methods can be classified into three categories: mechanical joining by means of such mechanical methods as riveting and bolting adhesive bonding by using glues or plastics welding by means of metallurgical bonding. In an oil and gas plant, we can see a thousand pieces of equipment that joined by many types of welding process. Welding can be defined as “the operation that produces coalescence of[…]

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gtaw welding definition

The effect of welding flame heating on the weld structure and the weld heat affected zone

weld heat affected Zone The welded joint can be divided into three main zones having different micro structures: base metal zone; heat affected zone; and a weld seam weld zone. In gas welding, due to slow heating , the heat affected zone (near- heat zone) is larger than in the case of arc welding . The thermal influence zone has several structural sections caused by the heating temperature in the range of 450-1500 ° C and differing in the shape and structure of the grain. The thermal influence zone consists of the following sections: incomplete fusion overheating normalization incomplete re-crystallization[…]

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