In this article we will discuss about the welding of metals:- 1. What is Welding? 2. Principles of Solid Phase Welding 3. Principles of Fusion (Liquid State) Welding 4. Weld Defects and Inspection. What is Welding?: Unlike the manufacturing processes employed to produce a single component, the joining processes are used to assemble different members to yield the desired complex configuration. [...]
Welding is broadly classified into two types: I. Plastic Welding: In this case the two pieces of metals to be joined are heated to plastic state and welding is completed by forcing them. In this case no filler material is added. II. Fusion Welding: In this case the two pieces of metal are heated and brought to molten state and [...]
Most important application of computer in welding is for the setting of welding parameters. Computer is used to control the welding process with regard to both static and dynamic characteristics. A computerised welding process controller is designed to handle the various phenomena occurring during the welding process, viz., the start-up sequence, continuous welding-including parameter setting, and the termination sequence. Start [...]
In this article we will discuss about:- 1. Meaning of Welding 2. Advantages of Welding over Other Joints 3. Welding Radiation 4. Weldability of Metals 5. Steps in Executing Welding 6. Characteristics 7. Heat Affected Zone (HAZ) in Welding 8. Recent Trends 9. Design 10. Quality Control 11. Inspection of Final Welds and a Few Others. Contents: Meaning of Welding [...]
For obtaining good results it is desirable that the surfaces should be clean and free from foreign materials. The cleaning can be done by wire brushing, machining or sand blasting. Impurities if present tend to make the joint weaker as the welded portion is filled with gas and slag inclusions and metal becomes brittle and the cohesion between the metals [...]
The following points highlight the five main types of resistance welding. The types are: 1. Spot Welding 2. Projection Welding 3. Seam Welding 4. Butt Welding 5. Percussion Welding. Type # 1. Spot Welding: This is probably the simplest form of resistance welding and best suited for ordinary sheet steel. For obtaining good welds having strength, and to avoid the [...]
The following points highlight the main thirty one methods of welding used in industries. The methods are: 1. Plastic Welding 2. Fusion Welding 3. Solid-Phase Welding 4. Cold Welding 5. Forge Welding 6. Pressure Welding 7. Flash Welding 8. Resistance Welding 9. Gas Welding 10. Oxyhydrogen Welding 11. Air-Acetylene Welding 12. Pressure Gas Welding 13. Atomic Hydrogen Welding and Few [...]
In oxyacetylene welding, the two gases used for producing flame are oxygen and acetylene. Oxygen is used to support and intensify combustion. It is generally prepared in factories by liquefying air and then separating it into its component parts by rectification. From factories, it can be obtained under high pressure in cylinders which are fitted with pressure regulators to get [...]
The following points highlight the equipments used for oxyacetylene welding. The equipments are: 1. Welding Torch 2. Pressure Regulator 3. Hose and Fittings 4. Cylinders 5. Goggles 6. Spark Lighter 7. Apron 8. Gloves 9. Welding Rods 10. Fluxes. Equipment # 1. Welding Torch: It is a tool for mixing the two gases in the desired volumes and burning the [...]
In this article we will discuss about:- 1. Meaning of Gas Tungsten Arc Welding (GTAW) 2. Advantages of GTAW Process 3. Polarities 4. GTAW Tungsten Electrodes 5. Shielding Gases. Meaning of Gas Tungsten Arc Welding (GTAW): Air during welding, (viz. oxygen, hydrogen, nitrogen and water vapour) tends to reduce the quality of weld. Inert gases are used to keep contaminants [...]