Found 60 Articles for Distribution of Electric Power

Carbon arc welding is used for welding copper and its alloys. In this method, the carbon electrode is used which is kept negative with respect to work if DC supply is used. It is because, if the carbon electrode is made positive, the carbon particles have a tendency to go into the welded joint and make it brittle. Therefore, the electrode in carbon arc welding is always kept negative and the work positive.For carbon arc welding, only DC supply can be used. In this welding method, the heat from the arc forms a molten pool and the extra metal required ... Read More

Heating ElementThe device which converts electrical energy into heat energy through the process of Joule heating is known as heating element. The heating element is the part of any electric heating appliance in which the electrical energy transformed into heat. The electric current through the element encounters resistance which results in heating of the element.Requirements of a Good Heating ElementA good heating element should possess the following properties −High ResistivityThe specific resistance or resistivity of the material used for making the heating element should be high. When the resistivity of the material is high, then the element will require small ... Read More

What is a Welding Position?The technique which allows a welder to join the metals in the position in which they are found or the position in which a specific component will be used, is called the welding position.According to the American Welding Society, there are following four welding positions in which arc welding is done −Flat PositionHorizontal PositionVertical PositionOverhead PositionFlat PositionThe flat position is also referred to as down-hand position. In the flat position, the metals to be welded are placed flat and the welder passes the electric arc over them.The important points about the flat position of welding are ... Read More

Electric HeatingThe process in which electrical energy is converted into heat by resisting the free flow of electric current is known as electric heating. Therefore, the heat is produced due to circulation of electric current through a resistance. This electric current may be circulating directly due to the application of potential difference or it may be due to induced eddy currents.Different Methods of Electric HeatingThe classification of methods used for electric heating is shown in the figure.Direct Resistance HeatingIn this method of electric heating, the electric current is passed through the substance to be heated. This method of electric heating ... Read More

Electric Arc WeldingThe electric arc welding is the welding process which uses electric arc to create heat to melt and join the metals. In the electric arc welding, the electric power supply creates an electric arc between the electrode and the base material.Depending upon the type of power supply used, the electric arc welding equipment is classified into two sections as −Direct Current (DC) Arc WeldingAlternating Current (AC) Arc WeldingEquipment Required for Electric Arc WeldingThe various equipment required for the electric arc welding (AC and DC) are shown in the figure and described below.Welding MachineThe welding machine used for electric ... Read More

Heat TransferThe heat transfer is defined as the transmission of heat energy from one region to another region as a result of temperature gradient. In actual practice, the heat transfer always takes place from the region of high temperature to the region of low temperature.Modes of Heat TransferThe transfer of heat energy from one region to another region takes place by the following three modes −ConductionConvectionRadiationIn a majority of real situations, heat transfer occurs as a result of a combination of these modes of heat transfer.ConductionWhen the heat transfers from one part of the substance to another part without the ... Read More

Resistance WeldingResistance welding is the welding process of joining of metals by applying mechanical pressure and passing a heavy current for a length of time through the metal parts which are to be joined. The chief advantage of the resistance welding is that it does not require any other material for creating the bond which makes it cost effective.Arc WeldingArc welding is the process in which the metals are joined by using electricity to create enough heat to melt metals, and the melted metals, when cool, result in the joining of the metals. The arc welding uses a welding power ... Read More

There are two types of electric currents used for welding process viz. AC and DC. There are many differences between the AC welding machine and the DC welding machine.AC Welding Machine Vs DC Welding MachineThe following table compares and contrasts the different features of AC and DC welding machines −AspectAC Welding MachineDC Welding MachineCostAC welding machine is less expansive.DC welding machine is 2 to 3 times costlier than AC welding machine.Size & WeightAC welding machine is smaller in size and light in weight.DC welding machine is larger in size and heavier in weight.OperationThe AC welding machine is simple to operate.The ... Read More

The choice of operating frequency for electric heating is a significant factor for heating because it greatly affects the work to be heated and the method of its heating, whether dielectric heating or induction heating.In practice, the furnaces operating on power frequency of 50 Hz can be of 1 MW capacity, those operating on medium frequencies (about 500 Hz to 1000 Hz) have a capacity of 50 kW and those operating on high frequencies (about 1 MHz to 5 MHz) have capacities ranging from 200 kW to 500 kW.Therefore, the factors which are considered while selecting the frequency for electric ... Read More

The atomic hydrogen arc welding is an arc welding process which uses an arc between two tungsten electrodes in a shielding atmosphere of hydrogen. The atomic hydrogen arc welding was invented by Irving Langmuir.The essentials of the atomic hydrogen arc welding are as follows −The electrical energy is supplied to create an arc between two tungsten electrodes where it is transformed into heat.The source of electrical energy could be either DC or AC, but in practice, AC supply should be chosen as it is commonly available.Molecular hydrogen is blown through the arc and transformed catalytically into the atomic form which ... Read More