Found 158 Articles for Electrical Engineering

Spot WeldingThe welding process which is used for welding two or more metal sheets together by applying pressure and heat from an electric current to the weld area is known as spot welding.Spot welding is a type of resistance welding process, which is why it is also known as the resistance spot welding.Schematic DiagramThe figure below shows the schematic diagram of resistance spot welding −Spot welding is the simplest and most universally adopted method of making lap joints in thin sheet up to a maximum thickness of 12.7 mm.A typical spot welding machine consists of a transformer to produce high ... Read More

Seam WeldingThe welding process in which two similar or dissimilar materials are joined at the seam by the application of heat generated from electrical resistance is known as seam welding. The seam welding is a types of resistance welding, in which weld is produced by roller electrodes instead of tipped electrodes.Most seam welding processes produce a continuous or intermittent seam weld near the edge of two overlapped metals by using two machine driven roller electrodes. As in the seam welding process, the roller electrodes move over the metal workpieces, the workpieces are under pressure and the current passing through them ... Read More

Polar CurvesThe plots drawn between the candle power and angular position are known as polar curves. Due to unsymmetrical shape of the lamps, the luminous intensity is not uniform in all directions. The luminous intensity in all directions can be represented with the help of polar curves.The polar curves are drawn by taking the luminous intensities in various directions at an equal angular displacement in the sphere. A radial ordinate pointing in any particular direction on a polar curve represents the luminous intensity of the source when it is viewed from the direction.Therefore, the polar curves are classified into two ... Read More

Laser Beam Welding (LBW) is a fusion welding process in which multiple pieces of metal are joined together through the use of laser. In LBW, the laser beam acts as a concentrated source of heat, which allows narrow, deep welds and high welding rates. The laser beam welding process is frequently used in high volume applications, such as in the automotive industry.Laser Beam Welding ProcessThe figure shows the schematic diagram of the laser beam welding (LBW).The main parts of the set up used for the laser beam welding are as follows −Laser Machine – It is the machine that is ... Read More

The light received by any surface depends upon the angle made by the normal to the surface, to the light flux. The Lambert's cosine law of illumination explains the relation between the illumination of the surface and the cosine of the angle.StatementThe Lambert's cosine law of illumination states that"The illumination of a surface is directly proportional to the cosine of the angle between the normal to the surface and the direction of incident light".That is, $$\mathrm{\mathit{E}\propto cos\, \theta \: \: \: \cdot \cdot \cdot \left ( 1 \right )}$$ExplanationCase I – Consider a surface that is normal to the luminous ... Read More

The flooding of large surfaces with light through powerful projectors, where the light sources are concentrated into narrow light beams using specific reflectors is known as flood lighting. Flood lighting is an artificial light with high-intensity, broad beam.Purpose of Flood LightingThe flood lighting may be employed for the following purposes −To enhance the beauty of the ancient monuments at night.To illuminate the railway yards, car parking, sport stadiums, construction sites, etc.To illuminate the advertising boards and show-cases, etc.Location and Mounting of ProjectorsIn practice, there are two possible locations of projectors for flood lighting, which are −For small buildings, uniform flood ... Read More

Flash WeldingFlash welding, also called flash butt welding, is a resistance welding process, in which the ends of the workpieces are pressed together and a heavy electric current is passed through the joint during the welding process.In flash welding, the electrical current is applied to the workpieces before they are brought together so that when they meet arcing (or flashing) takes place.Parts of Flash WeldingThe main parts of the flash welding process are described below −Power Supply – An AC power supply is used to provide power for the flash welding or flash butt welding.Welding Transformer – A welding transformer ... Read More

What is Electrolysis?The process of electrolysis can be defined in many ways −A technique that uses a direct electric current to stimulate a non-spontaneous chemical reaction is known as electrolysis.In other words, the process in which ionic substances are decomposed into simple substances by passing an electric current through them is known as electrolysis.Or, electrolysis is the process based on the fact that electrical energy can produce chemical changes, i.e., it can cause a chemical reaction to happen.Principle of ElectrolysisThe principle of electrolysis is based on the term "Electrolyte". An electrolyte is a substance containing free ions that make the ... Read More

What is Butt Welding?Butt welding is one of the simplest and versatile resistance welding process. In the butt welding process, heat is produced by the contact resistance between two metal workpieces. The faces of the workpieces should be machined or edge prepared.The circuit diagram for butt welding process is shown in the figure.In butt welding, the two workpieces are brought together and mechanical pressure is applied along the axial direction by a spring.A welding transformer is used that is having larger number of turns in the primary winding and smaller number of turns in secondary winding.A heavy current is passed ... Read More

The process of deposition of an oxide film on a metal surface is known as anodizing. The anodizing is an electrolytic passivation process, mainly used to increase the thickness of the natural oxide layer on the surface of the metal.This process is called anodizing because the metal part to be treated forms the anode electrode of the electric circuit of the process. The anodizing increases the corrosion resistance and wear resistance and provides better adhesion for paint primers and glues as compared to the bare metal.Requirements of AnodizingThe anodizing of metals is used for the following requirements −To provide the ... Read More