产品加工工艺的合理性

1．构成轮廓的几何条件 

在车削加工中手工编程时，要计算每个节点坐标；在自动编程时，要对构成轮廓所有几何元素进行定义。因此在分析图时应注意：

（1）图上是否漏掉某尺寸，使其几何条件不充分，影响到轮廓的构成； 

（2）图上的图线位置是否模糊或尺寸标注不清，使编程无法下手； 

（3）图上给定的几何条件是否不合理，造成数学处理困难。 

（4）图上尺寸标注方法应适应数控车床加工的特点，应以同一基准标注尺寸或直接给出坐标尺寸。

2．尺寸精度要求 

分析图样尺寸精度的要求，以判断能否利用车削工艺达到，并确定控制尺寸精度的工艺方法。 

在该项分析过程中，还可以同时进行一些尺寸的换算，如增量尺寸与对尺寸及尺寸链计算等。在利用数控车床车削时，常常对要求的尺寸取最大和比较小极限尺寸的平均值作为编程的尺寸依据。

3．形状和位置精度的要求 

图样上给定的形状和位置公差是保证精度的重要依据。加工时，要按照其要求确定的定位基准和测量基准，还可以根据数控车床的特殊需要进行一些

4．表面粗糙度要求 

表面粗糙度是保证表面微观精度的重要要求，也是合理选择数控车床、刀具及确定切削用量的依据。

5．材料与热处理要求 

图样上给定的材料与热处理要求，是选择刀具、数控车床型号、确定切削用量的依据。

Rationality of Product Processing Process
1. Geometrical conditions for the composition of an outline
When manual programming is done in turning, the coordinates of each node must be calculated; When programming automatically, all the geometric elements that make up the contour are defined. Therefore, when analyzing the map, it should be noted that:
(1) Whether a certain size is missing on the figure, making its geometric conditions insufficient, affecting the composition of the outline;
(2) Whether the position of the graph line on the graph is blurred or the size is unclear, so that the programming can not start;
(3) Whether the given geometric conditions on the graph are unreasonable makes mathematical processing difficult.
(4) The dimensional marking method on the figure should adapt to the characteristics of NC lathes. It should be marked with the same reference or directly give the coordinate size.
2. Size accuracy requirements
This paper analyzes the requirements of size accuracy of the pattern to determine whether it can be achieved by turning technology and to determine the process method for controlling size accuracy.
In the process of this analysis, some dimensions can be converted at the same time, such as incremental size and absolute size and size chain calculation. When turning a CNC lathe, the average of the required maximum and minimum limit dimensions is often taken as the programming size basis.
3. Requirements for shape and position precision
The shape and position tolerance given on the pattern is an important basis for ensuring accuracy. When processing, according to its requirements to determine the positioning benchmarks and measurement benchmarks, but also according to the special needs of CNC lathes to carry out some
4. Surface roughness requirements
Surface roughness is an important requirement to ensure surface microscopic accuracy, and it is also the basis for reasonably selecting CNC lathes and cutters and determining the cutting amount.
5. Material and heat treatment requirements
The material and heat treatment requirements given on the pattern are the basis for selecting tools, CNC lathe models, and determining the cutting amount.