Skip to main content

Introduction to Welding Technology

Welding is a fabrication process used to join materials, usually metals or thermoplastics, together. During welding, the pieces to be joined (the work-pieces) are melted at the joining interface and usually a filler material is added to form a pool of molten material (the weld pool) that solidifies to become a strong joint.
In contrast, Soldering and Brazing do not involve melting the work-piece but rather a lower-melting-point material is melted between the work-pieces to bond them together.

Types of Welding

There are many different types of welding processes and in general they can be categorized as:

Arc Welding: 

A welding power supply is used to create and maintain an electric arc between an electrode and the base material to melt metals at the welding point. In such welding processes the power supply could be AC or DC, the electrode could be consumable or non-consumable and a filler material may or may not be added.
The most common types of arc welding are:

Shielded Metal Arc Welding (SMAW): 

A process that uses a coated consumable electrode to lay the weld. As the electrode melts, the (flux) coating disintegrates, giving off shielding gases that protect the weld area from atmospheric gases and provides molten slag which covers the filler metal as it travels from the electrode to the weld pool. Once part of the weld pool, the slag floats to the surface and protects the weld from contamination as it solidifies. Once hardened, the slag must be chipped away to reveal the
finished weld.

  • Gas Metal Arc Welding (GMAW): 

A process in which a continuous and consumable wire electrode and a shielding gas (usually an argon and carbon dioxide mixture) are fed through a welding gun.

  • Gas Tungsten Arc Welding (GTAW): 

A process that uses a non-consumable tungsten electrode to produce the weld. The weld area is protected from atmospheric contamination by a shielding gas, and a filler metal that is fed manually is usually used.

Gas Welding: 

In this method a focused high temperature flame generated by gas combustion is used to melt the work-pieces (and filler) together. The most common type of gas welding is Oxy-fuel welding where acetylene is combusted in oxygen.

Resistance Welding: 

Resistance welding involves the generation of heat by passing a high current (1000–100,000 A) through the resistance caused by the contact between two or more metal surfaces where that causes pools of molten metal to be formed at the weld area. The most common types of resistance welding are Spot-welding (using pointed electrodes) and Seam-welding (using wheel-shaped electrodes).

Energy Beam Welding: 

In this method a focused high-energy beam (Laser beam or electron beam) is used to melt the work-pieces and thus join them together.

Solid-State Welding: 

In contrast to other welding methods, solid-state welding processes do not involve the melting of the materials being joined. Common types of solid-state welding include; ultrasonic welding, explosion welding, electromagnetic pulse welding, roll welding, friction welding (including friction-stir-welding), etc.

Comments

Popular posts from this blog

Waste of Transportation, 7 Wastes in Lean Manufacturing (SIX Sigma)

Transport is the movement of materials from one location to another, this is a waste as it adds zero value to the product. Why would your customer (or you for that matter) want to pay for an operation that adds no value? Transport adds no value to the product, you as a business are paying people to move material from one location to another, a process that only costs you money and makes nothing for you. The waste of Transport can be a very high cost to your business, you need people to operate it and equipment such as trucks or fork trucks to undertake this expensive movement of materials. Waste of transport is a consequence of excessively long, intersecting transport paths, temporary storage, load and unload, transport of pallets hither and thither. Waste of transport is also caused by too detailed process breakdown and exaggerated division of work, due to imprecisely defined intermediate warehouses and due to production in large series.  Waste of tra...

21st Century, Essay (IELTS)

The 21st century has begun. What changes do you think this new century will bring? Use examples and details in your answer. Man, through the ages, has undergone many changes from the time when he depicted a herd of mammoths on the walls of his cave to these days when he can create beautiful pictures and even make coffee by use of computer technologies without leaving his favorite chair. The 20th century made huge steps in developing computer technologies and reached many goals that made our life much easier. What should we expect in the 21st century? First of all, I think that the pace of our life will speed up: we will move faster from one place to another, from one continent to another using high speed jet airplanes. Second of all, I believe that we will be able to do many things that take much time now without leaving our house. Computers will be everywhere including out clothes. Many people will have chips and mini computers inserted in their heads to hold huge amount of ...

The Future of Mechanical Engineering (Emerging Technologies Trends)

  Mechanical Engineering, long centered on designing and producing mechanical systems, is undergoing a profound transformation driven by technological advancements and global challenges. Here are some of the most impactful trends and cutting-edge technologies shaping the future of the field: 1. Artificial Intelligence (AI) and Machine Learning Revolutionizing Processes : AI is transforming how mechanical systems are designed, tested, and maintained. Machine learning-powered predictive maintenance reduces downtime and extends the lifespan of machinery. Practical Example : AI-based simulations optimize product designs virtually, cutting down prototyping costs and accelerating the development process. 2. Additive Manufacturing (3D Printing) Transformative Impact : 3D printing enables the creation of complex designs that are unachievable with traditional methods, facilitating rapid prototyping and on-demand production. Future Prospects : Innovations in materials like metal alloys and c...