There are various systems available as part of modern CNC controllers which are

There are various systems available as part of modern

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life management function needs to be present. There are various systems available as part of modern CNC controllers, which are termed tool management systems that are able to keep track of the actual time for which each of the tool is in use. When the tools are entering the system (loading in the tool magazine), the expected tool life is entered in the controller memory along with all other tool related information such as offsets. This value is generally a conservative estimate of the tool life expected based on the work materials and the process parameters used. This value can be generally obtained from machinability data banks used on the shop floor or from previous experience. As machining proceeds with various components, the controller records the actual time for which each tool is used. This time used when subtracted from the expected tool life gives the left-over tool life for each tool. When the left over tool life is less than a certain nominal value, the controller initiates the action for replacing it by a sister tool. Controllers manufactured by Yamazaki, Fanuc, Sinumeric and others have this type of tool management option available with them.
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19 CNC Controls It is also possible to have tool life monitored outside the controllers, for example the tool life of all the tools present in the manufacturing system consisting of more than one machine tool may be monitored in an IBM PC compatible. Diagnostics To keep the machine utilisation high, it is necessary to check the health of the machine tool continuously. For this purpose a number of sensors are normally built into the machine tools. The control therefore should have the necessary ability to get the information from these sensors, analyse and then diagnose any faults already present or likely to come in future. Such diagnosis can be immediately communicated as alarms to the operator through the VDU. Alternatively with a built-in modem and a connected telephone line such information can be sent to the manufacturer or service facility for proper attention. Graphic Proving The part program before actually doing the machining can be simulated on the screen of the MCU to verify the accuracy of the geometry generated. This verification normally has a number of options such as the actual tool path shown in various 2D-view planes or with 3D such as isometric or axonometric projections. However, this type of simulation though fast will not give the real feel of the actual material removal process. Hence most modern controls provide a solid simulation process in which the blank and the tool are actually shown in 3D shaded image. As the tool moves through the work material, the material is actually removed as a solid subtraction between the work volume and the swept volume of the tool in contact with the workpiece. The layer removed is shown with a different colour to give a realistic feel of the material removal process. This process will be actually able to simulate the uncut material at the corners because of the tool radius, burr formation, etc. more realistically. Some controls can also incorporate the surface
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