Welding: Butt Joints

In welding, butt joints are used to join the edges of two plates or surfaces located in approximately the same plane. Butt joint is the most commonly used in the industry among all joint types. The following figure shows plain square butt joints of various thicknesses. As can be seen, there is no beveling of the two parts in … Read more

Surface Hardening of Steel

When an application requires a hard surface, it is not necessary that the entire body of the part be made up of a hard material. That would be uneconomical. A better way is to achieve hardening of the surface alone, while the base metal underneath continues to be plain carbon steel. This is called surface … Read more

Shutting Down Oxyacetylene Welding Equipment

It is essential that only a trained operator handle the equipment for oxyacetylene welding. Shutting down oxyacetylene welding equipment is as important as starting it up. Acetylene is a highly inflammable gas, and if it leaks, it can cause a fire and cause harm to life and property. In order to avoid accidents, and ensure … Read more

Welding: Lap Joint

There are mainly five types of joints in welding: edge joint, corner joint, butt joint, tee joint, and lap joint. This article discusses the ways in which a lap joint can be made. See the figure below. As the name suggests, lap joint refers to a joint when two parts ‘lap’ with each other, as … Read more

OxyFuel Cutting Steel And Cast Iron

This article discusses a few hands on tips to keep in mind while performing oxyfuel cutting of steel and cast iron. General Cutting of carbon steels can be easily done with an oxy-fuel torch. The low carbon steels containing less than 0.25% carbon do not pose much problem. However, for cutting of medium carbon and high carbon … Read more

Oxyacetylene Welding Torch

The oxyacetylene torch is a vital component of oxyacetylene equipment. Broadly speaking, it receives gas supply from the two gas cylinders (one for acetylene and other for oxygen), mixes them, and delivers them to the point of flame. Robust and precise construction of the oxyacetylene welding torch is important for obtaining a quality weld, and … Read more

Welding Over Paint

Welding over paint is not a straightforward matter as it might seem. Paints are made of complex chemical substances that vaporize upon coming in intense heat of the welding or cutting arc. These chemical vapors can be harmful to the health of personnel. Hence, welding directly over paint is generally discouraged. Most codes and standards … Read more

Arc Welding With Constant Voltage

In welding – 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

Wires For GMAW Welding

Electrodes used for gas metal arc welding process (or MIG Welding) are smaller than those used for other welding processes. This is because of the high current and speed at which the welding filler material is introduced into the weld puddle. The MIG welding wire comes in various sizes, and are available for most of … Read more