 Friends, I am Naval Emul working as an assistant professor in mechanical engineering department at Walton Institute of Technology, Sholapur. In this video, we are going to see the introduction to CNC machines. Learning outcome. At the end of this session, students will be introduced to CNC machine and its various features, content, introduction to NC and CNC, why CNC, advantages, disadvantages, and references. Numerical control. In numerical control system, intervention of human beings in the machining process is substituted by some operating instructions in the coded form. This coding, otherwise known as part program, is stored in cards or tapes. You will see the layout of the NC system. We get a product drawing. According to the product drawing, we do process planning. And in process planning, we go for the manuscript preparation. It is also called as part program. And according to the manuscript preparation or part program, we create punched cards or punched tapes. These punched cards and punched tapes are sent in the form of signals to the machine control unit. And these machine control units thus runs the machine tool. And in machine tool, there is a system which checks the position of the workpiece and the velocity of the spindle. Then it gives the feedback again to the machine control unit. And then again the signals are passed to the machine tool. And finally the product is completed. So in NC system, the main part is punched cards and punched tapes. So this is the layout of the NC system. As the complex parts and these punched cards cannot be used for the complex products or complex parts. So to overcome this, they have introduced CNC machines that is computer numerical control. When the activities of the numerical control machine is administrated by a dedicated computer, it is known as computer numerical control machine tool. The functions of the machine tool are controlled by the instructions stored as programmer in the computer. So we will see what is CNC machining. Computerized control, numerical control machining that is CNC machining is a method used to perform a wide range of manufacturing tasks which are all carried out by computerized devices. With the help of computer aided design that is CAD or computer aided machining that is SCAM. In the late 1970s, CNC machines replaced the old school manual machines that is lathe machines. The new CNC machines were able to be controlled by programming language to carry out a wider variety of tasks with greater accuracy. These machines also allow for the more accurate automated control which improves productivity. We will see the layout of the CNC system. The layout of the CNC system and the NC system are similar. The only difference between NC and CNC is in CNC we use the advanced computers whereas in NC we use a punched tapes or punched cards. So we will see the difference here, we get a product drawing, we go for the process planning and then the manuscript is prepared. And here in CNC we use computers to code, in computer we use different languages to write a program which is sent to the machine tool and from machine tool we go for the machine control unit. From machine control unit we get a feedback like we check the position of the workpiece we check the velocity of the spindle then the feedback is given back to the computer and if there are any correction the corrective measures are taken with the help of computer and again the signals are sent to the machine tools or else there is a product is completed. So if you get a screenshot of this CNC system and NC system you get to see the difference between CNC and NC. The only difference here is in computerized numerical control we used advanced computers whereas in numerical control they used to use punched cards and punched tapes. So we will see what is the necessity of the CNC, why you should choose CNC machine. So I will give you few seconds to think on it, why CNC? The CNC machine helps in producing parts with complicated outline, if there are some complex parts which cannot be easily manufactured with the help of traditional lathe machines we have to go for the CNC machines. So CNC is very helpful for producing the parts which have a complex shape, second they are used in manufacturing parts that require good repeatability. If there is a repeatability in the manufacturing parts that will be difficult for the human being also and for the operator also to perform the same task repeatedly on the traditional lathe machine. So for such reasons we are using a CNC machine where it is a very economical and very good repeatability. The help in generating parts that require costly jigs and fixtures. CNC also used in manufacturing parts that require several engineering modifications. CNC helps in producing the products which cannot be efficiently produced by human being. So we will see about the advantages of CNC. The CNC machine process, machining process is more precise than manual machining and can be repeatedly repeated in exactly the same manner over and over again. CNC machining produces complex shapes that would be almost impossible to achieve with manual machining. CNC machining is used in the production of many complex three dimensional shapes. Disadvantages of the CNC, the total setup of CNC machine is costly and need few skilled operators. It requires the knowledge of computers and programming knowledge is required. It has a difficulty in maintenance. Applications of the CNC machines, CNC machines are widely used in the metal cutting industry and are best used to produce the following types of products. Parts with complicated contours. Parts requiring close tolerance and or good repeatability. Parts requiring expensive jigs and fixtures if produced on conventional machines. Parts that may have several engineering changes such as during the development stage of a prototype. In case where human errors could be extremely costly, parts that are needed in the hurry. Small batch loads or short production runs. Some common types of CNC machines and instruments used in the industry are as follows. Drilling machine, lathe or turning center, milling or machining center, turret press and punching machine, wire cut electro discharge machine also called as EDM, grinding machine, laser cutting machine, water jet cutting machine, electro discharge machine, coordinate measuring machine, industrial robot. These are the references I have used, workshop technology, volume tube by Hazaraj Chaudhary, workshop technology by Raghuvanshi, workshop technology by W.A.G. Chapman, production technology by Gupta Patel. Patel, thank you.