It is an automatic process developed primarily for the production of high quality butt welds in thicker steel plates. SAW differs from other arc-welding processes in a way, that a blanket of fusible, granular material (flux) is used for shielding the arc and the molten metal. The deposition rate in this process is high and penetration is deeper. In this [...]
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 [...]
In this article we will discuss about:- 1. Meaning of Gas Metal Arc Welding (GMAW) 2. Components of GMAW 3. Modes of Materials Transfer 4. GMAW Practices 5. GMAW Welding using Fluxed Wire 6. Safety in GMAW 7. Characteristics of GMAW 8. Advantages of GMAW 9. Limitations of GMAW 10. Recent Advances in Welding Technology. Meaning of Gas Metal Arc [...]
With the engineering industry undergoing a radical transformation involving a steep step-up in production technology as well as production quantities, the need has arisen for welding systems designed for automation with consistent weld quality and dealing in materials much more complex than simple mild steel. 1. Thyristorised Universal Welding Rectifiers: These electronically regulated power sources which can take full care [...]
In this article we will discuss about the power sources for welding processes. Solid State Power Sources for Welding: Solid state power sources in comparison to conventional power sources are considered to be more efficient, have fast response characteristics and are must for some special jobs, particularly the applications performed with the aid of robots. In pulsed arc welding, a [...]
The electroslag process has been developed to weld seams of thick section or joints in a single pass, thus eliminating the need for multiple passes and preparation of bevel, V, U, or J groves and edge preparation. In this process, two plates, (1 and 2) to be joined together are arranged vertically as shown in Fig. 9.49. One to three [...]
In this article we will discuss about the meaning and equipments required for welding shop. Meaning of Welding Shop: Welding shop usually involves heavy equipment and as such should be provided with a concrete floor, preferably at ground level. To avoid fire risks, the structure should be fire resistant. In order to remove smoke generated by welding, the room should [...]
In this article we will discuss about the characteristics of some hyperbaric welding processes. Characteristics of Shielded Metal Arc Welding (SMAW): This is most widely used underwater welding process and can be used in both wet and dry environments. Wet welding is used for lightly stressed welds only. Hyperbaric SMAW process is most commonly used as it requires simple equipment [...]
In this article we will discuss about:- 1. Meaning of Plasma Arc Welding 2. Applications of Plasma Arc Welding 3. Advantages 4. Limitations. Meaning of Plasma Arc Welding: Plasma is defined as a gas heated to at least practically ionized condition, enabling it to conduct an electric current. Plasma arc refers to a constricted electric arc which is achieved by [...]
Thermit welding is the only welding process employing an exothermal chemical reaction for the purpose of developing a high temperature. It is a fusion process in which weld is effected by pouring super-heated liquid thermit steel around the parts to be united. The heat of “thermit” reaction is utilised to bring the surfaces of metal to be welded into plastic [...]