 Hello, I am Mr. D. J. Doshi working as assistant professor, Department of Mechanical Engineering while in the Institute of Technology, Solapur. At the end of this session, students will be able to perform different operations on lathe machine. Different operations which can be carried out on lathe machine are the grooving, parting, knurling, drilling, boring and threading. So, first one, grooving. It is the process of providing a narrow groove on the cylindrical surface of the workpiece. The shape of the tool is reproduced on the workpiece, so it is also known as form process or form turning. Now, in this process, the job is hold in a chuck which is mounted on the spindle. The job rotates along the axis of the spindle. It is supported from the front side by the dead center. Now, it is similar to the operation facing. In this tool, we will travel perpendicular to the axis of the lathe and it will generate the surface depending upon the shape of the tool, that is cutting shape of the tool. If the cutting shape is concave, the convex surface will be generated. If it is convex, the concave surface will be generated. If it is a flat one, it will be grooving with a right angle surface, that is parallel to the diameter of the shaft. Now, in this case, it is necessary to give slow speed to the workpiece and the tool, that is grooving tool called as or forming tool it is called as, it will be traveling perpendicular to the axis. Sometimes the chattering operations are observed or chattering symbols are observed on the diameter. So, it is necessary to make the tool move parallel to the axis also. So, depending upon the surface required, we will decide the tool. As I told, it will carry out forming also, that is concave convex surfaces as well as flat surfaces. The tool travel will be very slow because it will be chattering or it will be removing major length of the job depending upon the groove size and due to which sometimes vibrations are observed. So, finally, when we want finish surface at the end of completion of grooving, we will just remove slides, slide material from the diameter. So, this is called as grooving, the tool is also called as grooving tool and the operation is called as grooving or forming. This is parting, it is same as grooving, but in this case, we will be cutting the workpiece into two pieces. Now, it is the process of cutting a workpiece into two parts. The tool used is called same as parting operation or parting tool. So, here instead of maintaining the depth of the groove, we can, we will travel the tool till the axis so that the workpiece will be divided into three pieces, sorry two pieces. Now, in this case, the job is hold in a holding device or job holding device or workpiece holding device, it is depending upon the length of the workpiece, it may be supported from front side by dead center. If it is a length is small, then there is no necessity to hold it or support it from the front side. The tool will be similar to parting tool, but width will be less and will go on carrying out parting operation by giving feed to the tool perpendicular to the axis of the lathe till the workpiece is divided into two parts. So, it is similar to parting tool, parting operation, but of course, here there is no necessary to convert this parting tool into forming tool or form surface will not be generated on the cutting edge of the tool, only this will be flat surface and will go on carrying out it till the workpiece is divided into two parts. Third operation is called as knurling, it is the process of embossing a diamond shaped regular pattern on the surface of the workpiece using a tool called as knurling tool. It is not a metal cutting process, but squeezing of metal takes place during this process. And in this case also the rpm of the spindle or the circular motion of the workpiece will be less, because it is not removing the metal, it is squeezing the metal. So, it needs very slow speed and the tool which is called knurling tool on which diamond surfaces are produced to carry out the similar surface on the workpiece. So, in this case workpiece will be rotating along its own axis. Whether it is necessary to support from front side by dead center and the tool is actually pressed perpendicular to the axis on the workpiece. So, it will start generating the diamond knurling or diamond surface on the shaft and the tool will rotate along its own axis. If you observe this tool here, this is the tool. So, this tool diamond tool or knurling tool will be rotating along its own axis when it is pressed or it is feed is applied or depth of cut is applied here, it will start rotating along its own axis and it will generate similar surface on the workpiece. Here the simultaneous movement that is here the feed will be given horizontally or parallel to the axis depending upon the length of knurling surface required. So, suppose this has a 10 mm width and this has the knurling surface required is 30 mm length. It will be slide with the help of carriage parallel to the axis and depth of cut will be given with the help of cross slide and the diamond generated surface will be there. So, it is used for appianus good then this knurling knurling surface will give you grip for working. Now, usually tap wrenches, pipe wrenches and wherever we need grip to this surface. So, here if you hold there will be more grip than this flat surface or finish surface. So, the knurling is provided for looking appianus good for giving the gripping area more and this appianus also will be good. So, this question in which process metal squeezing takes place? I hope you might have written the answer. The answer of this question is knurling next is drilling operation. So, the limitation of drilling on lathe is that we can drill only along the axis of the work piece or along the axis of the lathe. So, we cannot generate hole other than the axis. So, it is the process of producing cylindrical hole in the work piece in this case the job is hold in a work holding devices the drill or tool of the drilling is hold in the spindle of tear stock. The tear stock is taken nearer to the work piece surface and it is clamped then by rotating the hand wheel the spindle will move along the towards the head stock and it will generate the drill hold in the spindle will generate the hole of the required size. If larger size hole is required we will go on changing the drill bit or the tool of drilling and we will go on increasing the aperture size or hole size. So, here the coolant is required and the speed will be depending upon the size of hole to be generated boring it is a process of enlarging the already existing hole in the work piece. So, this is similar to the turning operation here also the tool travel will be along the axis or parallel to the axis, but it will be inside the work piece it is not on the work piece. So, this is boring operation here the tool this is the tool which travels parallel to the axis again this depth of cut or depth of work aperture generated will be measured and accordingly it will be boring operation step boring operation. So, but for carrying out boring it is necessary to generate a hole at the center with the help of drilling. So, initially the drilling operation will be carried out and then with the help of boring tool it will be boring will be carried out if it is a depth control bore then you have to go on measuring the depth of the bore as well as diameter of the bore. If it is through drilling that is throughout the component or throughout the work piece drilling is there then this tool will travel till the end of the work piece. So, in this case no necessary to apply the dead stock dead center from here. Thread cutting it is the process of producing a helical groove of V or square shape on a cylindrical surface. In this case the tool will travel parallel to the axis, but as I told these distance that is distance between two threads that will be the travel of the tool for one rpm of the work piece. So, work piece is hold in a check and a particular gear train this is change gears. So, this gear train is so adjusted that for one rpm or one revolution of the component the tool will be travel by the distance between two threads. In this case dead center is required to support the component the job will be rotating very slowly the gear train will decide the speed of the feed travel or feed. The depth of cut we will go on increasing the depth of cut in this case half knot is used which will be engaging these are the half knot which will be engaged with the lead screw which will decide the tool travel. So, thread cutting tool will travel in such a way that for one revolution of the work piece it will travel by distance between two thread and the repeated operations or repeated cycles will be deciding the depth of the thread. So, depending upon the depth of the thread will repeat the cycles and the threading operation will be carried out. So, here we are engaging the half knot whereas, in other cases we will never engage the half knot. For this I used BL single a textbook of basic mechanical engineering Techmax publication. Thank you.