Nc machine programming includes several aspects
In general, programming involves the following aspects:
1. Processing technology analysisThe programmer should first analyze the processing technology of the parts according to the parts drawing, such as material, shape, size, precision and heat treatment requirements.Reasonable selection of processing program, determine the processing sequence, processing route, way of loading, cutting tools and cutting parameters;At the same time also consider the numerical control machine tool instruction function, give full play to the efficiency of the machine tool;The processing route should be short and the number of tool changes should be few. 2. Numerical calculationAccording to the geometric dimension of the part drawing, determine the process route and set the coordinate system, calculate the track of the rough and fine machining movement of the part, and obtain the tool position data.For parts with simple shapes (such as parts composed of straight lines and arcs) contour machining, geometric elements to calculate the starting point, the end point, the center of the arc, the intersection of two geometric elements or the point of contact coordinate value, some also calculate the center of the tool movement trajectory coordinate value.For parts with complex shapes (such as parts composed of non-circular curves and curved surfaces), it is necessary to use straight line or circular arc to approximate and calculate the node coordinate value according to the requirements of machining accuracy. Generally, such numerical calculation shall be completed by computer.
3. Preparation of processing proceduresAfter determining the machining route, process parameters and tool position data, the programmer can write the machining program section by section according to the functional instruction code and program segment format specified by the numerical control system.If the programmer and the machiner are separated, the necessary machining schematic diagram, tool parameter table, machine tool adjustment card, process card and relevant text description should also be attached.
4. Preparation of control mediumThe programmed program is recorded on the control medium as input information of the numerical control device.To feed into a numerical control system by manual or communication transmission.
5. Program checking and first piece trial cuttingThe written program and prepared control medium can only be used officially after being tested and cut.The method of verification is to directly input the content of the control medium into the numerical control system, let the machine tool run empty, to check whether the motion trajectory of the machine tool is correct, or through the numerical control system to provide graphics simulation function, on the CRT screen, simulation tool motion trajectory.However, these methods can only check whether the motion is correct, not the machining accuracy of the processed parts.Therefore, the first part of the trial cut.When machining errors are found, analyze the causes of the errors, find out the problems and correct them.