Welding Distortion and Warpage

Warpage in welding and residual stresses occurring in welds are a nuisance for any welding engineer. The distortion spoils the aesthetic appeal of the product, and affects its usability for the intended purpose. Residual stresses can give rise to initiation of fracture in the metal, which can result in catastrophic failure. Therefore, it is important … Read more

Multipass Welding: All You Need To Know

Multipass welding is typically required when thick sections are required to be welded.  This technique is used in the industry for joining of thick sections, carrying out repairs, build ups, surface hard-facing and so on. As the name suggests, multipass welds consist of multiple passes of welding in a joint.  One pass of the weld is generally … Read more

Welding Stresses and Cracking

Welding stresses are an unavoidable feature of any welding. Stresses inside a weldment may result in many undesirable consequences such as distortion, buckling, warping, lamellar tearing, cracking, brittle fracture, fatigue fracture etc. When weld metal is added to a joint, it is akin to cast metal. When the weld metal cools, it contracts. This is … Read more

Pipe Welding

Welding of pipes is commonplace. Pipes are used for transporting oil, water, gas, etc. The pressure inside the pipe may range from a vacuum pressure to gage pressure running into several hundreds of pounds per square inch. For such joints, mechanical joints such as rivets, threaded joints, etc. are not adequate for the purpose, hence … Read more

Welding Arcs

Welding arcs is a source of intense heat that is used to melt the base metal and filler metal to produce a weldment. Arc is where the real action happens, in the course of all arc welding processes. In this article, we shall discuss in brief about the function of welding arcs, and different kind of forces … Read more

Weld Failure Analysis

Failure of a weld can have serious consequences. A weld failure in the backyard of house may not have much consequences. However, when the weld lies in a large sized pressure retaining equipment, weld failure can cost heavily on life and equipment. Such failures have to be analysed by an expert or a team of … Read more

Mechanical Properties Of Metals

The mechanical properties of a metal determine its’ suitability for an application. The properties help in predicting the behaviour of metals under certain conditions. The knowledge about properties of a metal also helps in specifying the requirements during procurement of raw materials for fabrication of equipment. From a welding point of view, quantifying the behaviour … Read more

Welding Electrical Circuit

In order to understand about the polarity in an arc welding circuit, it is first important to understand the construction of the arc welding circuit. This article discusses a few terms used in any electrical circuit such as EMF, current, and resistance. The later part of the article equates the welding electrical circuit to ordinary … Read more

Arc Welding With Constant Voltage

In welding β€“ besides the current current power source, the second type of power source is the constant voltage (CV) machine or the constant potential (CP) machine. It has a relatively flat volt-ampere characteristic curve. In this article we shall discuss about arc welding with constant voltage. Features Of A Constant Voltage Machine The figure below shows … Read more