resistance welding resistance is the property of the conductor by the virtue of which it resists the flow of electrons that is the flow of current through it this resistance to the flow of electrons creates friction and heat this heat generated is then used to join the two similar or dissimilar metals by melting and forming a bond between them types of resistance welding processes 1. spot welding 2. seam welding spot welding spot welding is also known as the resistance spot welding process it is used to weld thin sheets of metal together by applying pressure the heat required for welding is generated by resistance to the flow of current through the electrode working principle the welding electrodes are made up of copper which is a good conductor of electricity the movable and fixed electrodes of the spot welding machine are held in pressure on either side of a pair of plates to be welded together as the current passes it experiences the resistance between the electrode and workpiece contact and generates heat this heat causes the interface of the workpiece in contact with another work piece to melt and pressure fuses the two metals thus forming a solid bond if you are enjoying this video please give this video a thumbs up and if you are new to adtw learn click on the subscribe button and turn on the notification to get more informative videos like this equipment required spot welding machine tongs also known as electrodes working of spot welding when the power is turned on the transformer supplies the low voltage high current to the electrodes made up of copper these electrodes are held in pressure against a pair of work pieces to be spot welded with the help of tongs the current flows from the tongs to the electrodes as copper is the good conductor of electricity but faces resistance at the point of contact between the two work pieces this resistance generates the heat at metal to metal interface and causes the two metals in contact to melt then the pressure causes the molten metal to fuse together and thus a solid bond is formed application of spot welding spot welding is used for welding thin sheets together in the manufacturing of fuel tanks joining vehicle body parts radiators wire ends etc advantages of spot welding the process can be automated the process is simpler no filler metal is required low or no fumes is generated the high welding rate is possible limitations of the spot welding process the initial cost is high low strength due to discontinuous weld the process is limited to the thickness of the metal seam welding in seam welding the workpiece is supported on both sides by a pair of electrodes these electrodes are in the form of rollers to produce a continuous weld on the workpiece continuous spot welding is known as seam welding the working principle of seam welding is similar to that of resistance spot welding equipment are components used in the process seam welding machine and roller electrodes working of seam welding when the power is turned on the transformer supplies the low voltage high current to the roller electrodes made up of conductive materials these roller electrodes support the pair of work pieces to be welded together when the rollers are made to contact the workpiece the current flows easily through the roller electrodes with a low resistance but experiences a high resistance at the metal to metal interface that is between the upper plate and lower plate to be joined thus high resistance to the flow of current offered by the pair of workpiece raises the temperature to the fusion point between the workpiece interface and a weld is generated in the form of a nugget nugget as a weld between the two workpiece interfaces application of seam welding process welding of transformer paint containers welding of gasoline tanks automobile mufflers welding of sheet metal tanks advantages of seam welding it can generate a leak-proof weld the production rate is high dissimilar metals can be welded together no filler metal or flux is needed the processes can be automatic or semi-automatic it is possible to weld thin metal sheets with this process a semi-skilled person can also produce a good weld limitations of seam welding the welding process is suitable for thin sheets only up to a thickness of three millimeters since the electrodes are in the form of rollers they can weld only along a straight line or well curved path the process is limited to the lap joints i hope you have understood resistance welding in its types it takes lots of effort to make such informative videos you can help adtw learn to make more videos by joining our channel and contributing to developing more such videos your support will help us make great educational videos other ways of helping us are by sharing our videos with your friends thank you