The manufacturability analysis of NC machining parts is an important link in NC machining process, which is directly related to machining quality, efficiency and cost. The following is a detailed summary of the manufacturability analysis of CNC machining parts:
First, part drawing analysis
Dimensioning method: The dimensioning method on the part drawing should adapt to the characteristics of CNC machining, and quote the size with the same reference or directly give the coordinate size. This annotation method is not only convenient for programming, but also conducive to keeping the consistency of design datum, process datum, test datum and programming origin setting.
Geometric element conditions: Analyze whether the conditions of the geometric elements constituting the outline in the parts drawing are sufficient and correct to avoid problems in programming.
Accuracy and tolerance: Analyze whether the machining accuracy and dimensional tolerance required by the parts can be guaranteed, and whether there are excess dimensions that cause contradictions or closed dimensions that affect the process arrangement.
Second, part structure manufacturability analysis
Shape and structure: Analyze the shape, structure and size characteristics of the parts to determine whether there are parts that hinder the movement of the tool, whether there are areas that will produce processing interference or processing.
Processing requirements: Check the processing requirements of the parts, such as dimensional machining accuracy, form and position tolerances and surface roughness can be guaranteed under the existing processing conditions, and whether there are more economical processing measures or programs.
Tool restrictions: Check whether there are parts and size regulations that limit the shape and size of the tool, such as transition fillet, chamfer, slot width, etc., whether these dimensions are too messy, and whether the specifications can be unified to reduce the number and time of tool change and tool matching.
Process datum: Analyze the process datum on the part, which determines the order of each processing process, and will also have a direct impact on the position accuracy between each processing surface after each processing process.
Third, the selection of processing methods
Processing accuracy and surface roughness: When selecting the processing method, the processing accuracy and surface roughness requirements of the machined surface should be ensured. For the requirements of the same level of precision and surface roughness, there may be a variety of processing methods to choose from, so it is necessary to consider the shape, size and heat treatment requirements of the parts.
Productivity and economy: When selecting the processing method, the requirements of productivity and economy, as well as the actual situation of the factory’s production equipment, should also be considered.
Fourth, the choice of fixture
The basic requirements of the fixture: CNC machining has put forward two basic requirements for the fixture, one is to ensure that the coordinate direction of the fixture is relatively fixed with the coordinate direction of the machine tool, and the other is to coordinate the size relationship between the parts and the machine coordinate system.
Fixture type: Select the appropriate fixture type according to the processing batch and part characteristics, such as combined fixture, adjustable fixture, special fixture, etc.
Fifth, the choice of tools
Tool requirements: CNC machining has higher requirements for tools, which not only requires high precision, good stiffness and high durability, but also requires stable size and easy installation and adjustment.
Tool type: Select the appropriate tool type according to the shape, material and processing requirements of the machined parts, such as end milling cutter, ball end milling cutter, drum cutter, cone cutter, etc.
Sixth, the determination of cutting parameters
Cutting parameters: cutting parameters include spindle speed (cutting speed), back cutting tool amount, feed amount, etc. The selection of these parameters has an important impact on processing efficiency, processing quality and tool life.
Selection principle: In the selection of cutting parameters, should be based on the performance of the machine tool, tool materials, workpiece materials and processing requirements and other factors to ensure the stability and economy of the processing process.
Seventh, the determination of processing routes and the division of processing procedures
Processing route: The determination of processing route directly affects the processing accuracy, use efficiency and economic benefits of CNC machine tools. When determining the processing route, factors such as the rigidity of the workpiece, the durability of the tool and the processing efficiency should be considered.
Processing process division: According to the parts pattern and processing requirements, reasonable division of processing processes and steps to ensure the continuity and stability of the processing process. At the same time, the connection and conversion between processes should also be considered to reduce auxiliary time and improve production efficiency.
In summary, the manufacturability analysis of CNC machining parts is a comprehensive and complex process, which needs to consider a number of factors to ensure the optimization of processing quality, efficiency and cost.
