After choosing the CNC processing method and dividing the working procedure, the main content of drawing up the technological route is to arrange the processing method and the sequence of the working procedure reasonably. CNC processing of parts usually includes cutting process, heat treatment process and auxiliary process (including surface treatment, cleaning and inspection, etc.). The sequence of these processes directly affects the quality, production efficiency and processing cost of parts. Therefore, when designing the process route of cnc, the sequence of cutting, heat treatment and auxiliary processes should be reasonably arranged, and the connection between processes should be well solved.

Arrangement of CNC processing procedures:

(1) First coarseness, then refinement

For example, according to the order of rough turning, semi-finish turning and finish turning, the processing accuracy is gradually improved. Rough turning will cut off most of the machining allowance on the surface of the workpiece in a relatively short period of time. On the one hand, it improves the metal removal rate, on the other hand, it satisfies the requirement of uniformity of the margin of the finishing car. If the uniformity of the remaining allowance after rough turning can not meet the requirements of finishing, semi-finish turning should be arranged to prepare for finish turning. Precision turning should ensure the accuracy of processing, according to the size of the drawings cut out the outline of the parts with one knife.

(2) Near and Far First

Generally speaking, the cutting tool is processed first from the modern part of the tool setting point and then from the part of the tool setting point element, so as to shorten the moving distance of the tool and reduce the empty travel time. For turning, it is beneficial to keep the stiffness of the blank or semi-finished product and improve the cutting conditions by going near the sea first and then far away from the sea.

(3) Principle of Internal and External Crossing

For parts with both inner surface (inner cavity) and outer surface to be machined, rough machining of inner and outer surface should be carried out before finishing of inner and outer surface. Never finish machining a part of the surface (outer surface or inner surface) of the part and then process other surfaces (inner surface or outer surface).

(4) the principle of base-level advance

Priority should be given to surface processing as a precise reference. This is because the more accurate the surface of the positioning datum is, the smaller the clamping error is. For example, when shafts are processed, the center hole is usually processed first, and then the outer circle surface and the end face are processed with the center hole as the precise datum.

(5) Principle of Priority First and Secondary

The main working surface and assembly base surface of the parts should be processed first, so that modern defects may occur on the main surface of the blank as early as possible. Secondary surfaces can be interpolated and placed before the main surface processing and final finishing.

(6) The principle of face before face

The plane outline size of box and bracket parts is large. Generally, the plane is processed first, and then holes and other dimensions are processed. In order to arrange the processing sequence, on the one hand, it is stable and reliable to use the machined plane positioning; on the other hand, it is easy to process holes on the machined plane, and it can improve the processing accuracy of holes. It is not easy to deviate the axis of holes when drilling holes.

After choosing the CNC processing method and dividing the working procedure, the main content of drawing up the technological route is to arrange the processing method and the sequence of the working procedure reasonably. CNC processing of parts usually includes cutting process, heat treatment process and auxiliary process (including surface treatment, cleaning and inspection, etc.). The sequence of these processes directly affects the quality, production efficiency and processing cost of parts. Therefore, when designing the process route of cnc, the sequence of cutting, heat treatment and auxiliary processes should be reasonably arranged, and the connection between processes should be well solved.

Arrangement of CNC processing procedures:

(1) First coarseness, then refinement

For example, according to the order of rough turning, semi-finish turning and finish turning, the processing accuracy is gradually improved. Rough turning will cut off most of the machining allowance on the surface of the workpiece in a relatively short period of time. On the one hand, it improves the metal removal rate, on the other hand, it satisfies the requirement of uniformity of the margin of the finishing car. If the uniformity of the remaining allowance after rough turning can not meet the requirements of finishing, semi-finish turning should be arranged to prepare for finish turning. Precision turning should ensure the accuracy of processing, according to the size of the drawings cut out the outline of the parts with one knife.

(2) Near and Far First

Generally speaking, the cutting tool is processed first from the modern part of the tool setting point and then from the part of the tool setting point element, so as to shorten the moving distance of the tool and reduce the empty travel time. For turning, it is beneficial to keep the stiffness of the blank or semi-finished product and improve the cutting conditions by going near the sea first and then far away from the sea.

(3) Principle of Internal and External Crossing

For parts with both inner surface (inner cavity) and outer surface to be machined, rough machining of inner and outer surface should be carried out before finishing of inner and outer surface. Never finish machining a part of the surface (outer surface or inner surface) of the part and then process other surfaces (inner surface or outer surface).

(4) the principle of base-level advance

Priority should be given to surface processing as a precise reference. This is because the more accurate the surface of the positioning datum is, the smaller the clamping error is. For example, when shafts are processed, the center hole is usually processed first, and then the outer circle surface and the end face are processed with the center hole as the precise datum.

(5) Principle of Priority First and Secondary

The main working surface and assembly base surface of the parts should be processed first, so that modern defects may occur on the main surface of the blank as early as possible. Secondary surfaces can be interpolated and placed before the main surface processing and final finishing.

(6) The principle of face before face

Planar wheels for box and bracket parts