WELDING SHOPWelding is the process of joining of two similar metals or dissimilar metals.

In welding shop we mainly saw two types of welding which is oxy fuel gas welding and consumable electrode arc welding process.

Arc Welding-an arc is produced between the tip of the electrode and the work piece to be welded by the use of an AC or a DC power supply. This arc produces temperatures of about 30000 deg Celsius much higher than those developed in oxy fuel gas welding. Shielded metal arc welding is the most commonly used welding method.

SMAW :- SHIELDED METAL ARC WELDING

Used in general construction and maintenance work Portable and easily maintained Useful for work in remote areas where portable fuel power

generator can be used as power supply Best suited for work piece thickness 3mm-19mm

OFW:-OXYFUEL GAS WELDING

It is used for structural sheet metal fabrication, various repair works. The welding process uses a fuel gas combined with oxygen to produce flame. The flame is source of heat that is used to melt the metals at the joint. The process utilizes the heat generated by the combustion of acetylene gas in a mixture with oxygen.

C2H2 + O2 =2CO + H2 + heat

OFC-OXYFUEL GAS CUTTING

A piece of material can be separated into two or more pieces or into various contours by the use of a heat source that melts and removes a narrow zone in the work piece. The sources of heat can be torches, electric arcs, or lasers.

The heat source is now used to remove a narrow zone from a metal plate or sheet. Heat is generated here and it can produce a temperature rise to about 8700C. However, this temperature is not sufficiently high to cut steels, so the work piece is preheated with fuel gas, and oxygen is introduced later. Cutting occurs mainly by the oxidation of the steel; some melting also take place.

OVERVIEW:-

Max thickness cut is about 300mm to 350mm with oxyacetylene gas

With oxy hydrogen about 600mm Kerf width ranges from 1.5mm to 10mm