welding method

Welding method

Welding

Welding is used everywhere today, whether it is to make a small device or to make a big aircraft. Wherever two or more metals are interconnected or joint together, welding is always used.

Definition of welding

The definition of welding is as follows: -

The process of connecting metal or metals to another metal by heating them to extreme temperatures and pressure or without
the pressure is called welding.

But the same type of welding cannot be used on all metals, hence different types of welding are used to use on different metals and at different places.

. Leftward welding:

It is also called forward welding. For this, the filler rod is held in the left hand and the welding torch in the right hand and welding is started from the right side and extended to the left.

Rightward Welding:

In this also the filler rod is held in the left hand and the welding torch in the right hand but welding is started from the left and extended to the right.

Vertical welding:

This is a very useful and economical method that is used on plates of any thickness, but this welding is possible only when the plates are placed in vertical positions. It starts from the bottom of the welding plate and moves towards the top.

Preparation Before Welding

Before welding, the assembly parts are placed at a certain distance and then welding is done. By doing this, the fusion reaches the required depth during welding or complete penetrations to the full depth of the joint.

Before welding, small welds are applied at short distances to assemble the connecting pieces. By doing this, the gap and alignment between the parts of the assembly can be maintained for fusion to a certain depth and control the defects during welding.

Step Before Welding

Root Gap: preparation
Tech welding
Inspection and testing of welded joints

Welding Joints
There are several types of welding joints that depend on the thickness and type of base metal.

The common welding joints are given below

Butt Joint
Lap Joint
T Joint
Edge Joint
Corner Joint

Type of welding

In general, we can classify it in two types, It is explained in detail below.

1-Arc welding

With this type of welding, the electric arc is a strike and produced heat at the welding point between the electrode and the base material, so that the electrode/filler metal melts to the welding point and subsequently the molten metal cools.

Arc welding itself has many types of welding methods,

Type of Arc welding

SMAW (shielded metal Arc welding)
GTAW (Gas Tungsten Arc welding)
CAW (Carbon Arc welding)
SAW (Submerged Arc welding)
GMAW (Gas Metal Arc welding)/MIG
PAW (plasma Arc welding)
ASW (Arc Spot Welding)
Electroslag welding
Electrogas welding
SW (Stud Arc Welding)
FCAW Flux Cored Arc welding

Arc Welding Equipment

2-Gas Welding

Gas welding It melts and sets itself automatically at the wedding point.
In this process, the gas is burnt with the help of oxygen and the filler material is melted at high temperature with the help of concentrated fire and applied to the welding point so that it is melted and set automatically at the wedding point.

Type of Gas welding

Gas welding itself has many types of welding methods, It is explained in detail below.

Air-acetylene Welding
Oxyhydrogen welding
Oxyacetylene welding
Pressure gas welding

Gas welding operation

The most important part of gas welding is the welding flashlight as the welding flashlight comes from the two and they are joined together and two VALVES are applied to the welding flashlight which is also used to control their pressure. is. After the fire burns in the welding flashlight, it emits from its nozzle and is placed on the welding plate. The size of the welding torch's nozzle depends on the welding plate and material

A sufficient amount of oxygen is required to ignite the fuel, hence oxygen cylinders are used so that whenever more engines are required to run, more oxygen can be given to it. And the oxygen cylinder is always black.

Gas Welding equipment

Welding transformer is required for welding. This transformer converts high voltage low ampere input current into low voltage and high ampere current and it provides AC supply for welding. In addition, a motor-generator is required. It is used for welding of ferrous and non-ferrous metals.

The following equipment and accessories are used under the gas welding process.

1. Oxygen Cylinder

2. Acetylene Cylinder

3. cylinder manifold

4. A hydraulic back pressure valve

5. Flashback arrestor

6. Gas Purifier

7. Safety valve

8. Pressure regulator or gas regulator

9. Hose Pipe

10. welding flashlight or blowpipe

11. lighter or igniter

12. cylinder trolley

Fuel Gas Cylinder:

Gas cylinders are mostly filled with Oxy Acetylene Gas, Hydrogen Gas, Natural Gas or any other flammable gas. This gas depends on the welding material as to what type of welding material is used but mostly Oxy Acetylene Gas is used. This cylinder is maroon colored

Pressure Regulator:

Oxygen and fuel gas cylinders contain very high-pressure gas. But welding does not require such high pressure, so to control this pressure a pressure regulator is applied to it so that we can welding at the pressure we need. About 70 - 130 KN / M2 of oxygen pressure is required for welding and 7 - 103 KN / M2 of gas is required.

Gas Welding Working:

Gas welding is like arc welding, only equipment is used separately in it. Before starting gas welding, connect the gas cylinder and the oxygen cylinder thoroughly and also check the press regulator. And open the pressure regulator as required and then light a fire with Striker next to it. And now set the flame to Natural Flame or Carburizing Flame or Oxidizing Flame according to the welding condition. And start welding.