 Hello everyone, this is Shila Ratna Bansode from Vulture Institute of Technology, Solar Power. Today we are going to see the topic BIS Conventions that is Bureau of Indian Standard Conventions and in that we will be particularly seeing the welding joints and their respective BIS symbols, learning outcomes. Students will be able to describe different types of welding joints and students will be able to apply BIS conventions of welding in drawing. Now at this moment of the video, I suggest you to pause the video and recall the components that you have seen are formed with the help of welding. Moving further, now welding is used for making permanent joints. The joints formed with the help of welding are leak proof, are better and give you permanent joints. Welding is a better replacement for forging and casting processes. As compared to riveting process, welding is cheaper, low cost, stronger, the bond formed or the joint formed with the help of welding is stronger and it is the easiest method or easier method as compared to riveting. Welding is widely used in shipbuilding and structural fabrications. Forming big structures of metals, of steels, fabrication is in fabrication, welding is preferred. Now moving further, different types of welds. Here on screen you can see the sectional area are the different plates arranged in fashion to show the different types of joints. The first and the foremost joint that we see is the corner joint. We will start with this corner joint. The plates are kept at 90 degrees and the remaining portion of the plate is being welded. So this form of weld is called as corner joint. Then we have lab joint. Lab joint, one plate is placed over the other. So this plate and this plate are placed one above the other, one above the other. The joint formed here is called as lab joint, is called as lab joint. Then here also we can have a lab joint. Now considering these two plates which are placed exactly next to each other or face to face, the two faces are joined and when the welding is done at their edges, it is called as edge joint. So corner joint, lab joint and edge joint. Now considering these two plates, this vertical plate and this horizontal plate. Here you have T joint because the two plates are in T fashion. This is first T joint. Considering this plate and this horizontal plate, we have another T joint. And the most common welding joint that is seen everywhere is butt joint. In butt joint, the two plates are placed face to face in front of each other, exactly in front of each other. You can see this is the first plate, this is the second plate and this is the area that is being welded. So butt joint is the most commonly or widely used joint for welding or in welding. So the different types of weld joints that we have seen is corner joint, lab joint, this and this. Then we have T joint, this and this. When the plates are placed at a fashion of T, then we have edge joint when the plates are placed exactly next to each other. And then we have butt joint when the plates are placed in front of each other. As in this fashion. So these are the different types of joints that are being used when welding the components depending upon the application, depending upon the requirement. We prefer any one type of joint for joining the two metals with the help of welding. Moving further. Now we are coming to position of weld symbols on drawing. So this is the convention how a welding part is being represented over here. Now you can see this line, this is the part where joint is formed, the lower one. Now from there we draw an inclined line called as reference line. Then we have a horizontal line, another reference line. So this is called as arrow line and this is called as reference line. Then above that we have the welding symbol. So this is the welding symbol. What kind of welding symbol is this? We look further. This is the welding symbol. Here an entity is written and here an entity is written. So on the left and right side of the weld symbol, we have two numbers or two entities written over there. A5 represents the thickness or the cross section of the weld that is to be welded or welded. And 300 over here represents the length of weld to what extent the welding needs to be done or carried out. So this is the arrow line. Then we have the reference line and another reference lines we can see that is in the form of dotted line. So this is another reference line. This is optional but the compulsory thing is this arrow line and this horizontal reference line. Continuous horizontal reference line. So this is the general symbol that is used to show welding in drawing with the help of conventions. Then we will move further. Now position of weld symbols on drawing another fashion. These are the two plates to be welded. The arrow is pointing towards the welded side. So this is the arrow side and this is the other side. Similarly over here, when the arrow is pointing towards the welded side or the welding is done on the arrow side, this is called as arrow side of the welded plates. This is called as other side of the welded plates. Similarly over here. So this is the arrow side of the welded plate. This is the other side of the welded plate. plate, this is the other side of the welded plate. These two plates are being welded. Considering these two plates to be welded, so this is the arrow side of the weld and this is the other side of the weld. Now how this is represented? For symmetric welding, this is the symbol. Both side, the welding symbol is represented above the reference line and below the reference line. Now when welding is to be done on other side, so this is the symbol. The welding symbol is represented on the dotted line. When you weld the component on other side of the arrow and on the arrow side, you show the welding symbol on the continuous horizontal line, on the continuous horizontal line. So this is towards the arrow side and this is towards the other side and when you have symmetrical welding on both the sides, you show this symbol. So this was by the position of other side and arrow side. Now moving further, this is the butt weld, the most common butt weld with raised edges and its symbol is this. Then square butt weld, the two plates are exactly placed in front of each other. There is no raised edges, so two parallel lines representing the square butt weld. Then we have single V butt weld. So the symbol that we have seen previously over here is the V butt weld symbol. Single V butt weld, where this is the first plate and this is the second plate to be welded and a V is formed in between the two plates. This is called as edge preparation. Depending upon the component to be welded, the two edges are being formed into some shapes. As you can see here V shape. So this is single V butt weld. Then we have single V weld butt weld in this fashion. Here only V butt weld. Here V weld, a slight inclination to this line. So V weld butt weld. Then we have single V butt weld with broad root faces. Here you can see the root faces broad. Here a broader area is given as compared to the previous one. So a line is included over here. So this is only a V and a line to it gives you with broad root face. Similarly single V weld butt weld with broad root face. V weld is this. You have a broad root at the bottom. Broad area to be welded. This is called as single V weld butt weld with broad root face. Then we have single U butt weld. The weld is in U fashion with broad root. So this is single U butt weld. This symbol is this. Then we have fillet weld or T weld what we have seen previously. Then we have spot weld. The welding is done at exactly two spots to be weldeded. The two plates to be welded. This symbol is in circular fashion. Then we have seam weld where the welding is done through the length throughout this length. The symbol is in this fashion. So this was with the welding symbols. This is the reference. Thank you.