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