Application of cadcam in the hottest high speed ma

The application of cad/cam in high-speed machining (middle)

II. The influence of cam on high-speed machining

although many research institutions have studied high-speed machining for many years, there is still no clear and concise definition and explanation at present. The basic starting point of high-speed machining is that cutting at high speed and low load can cut materials faster than cutting at low speed and high load. Low load cutting means that * times of force can be reduced when the cutting sample returns to the starting position, so as to reduce the vibration and deformation in the cutting process. In the state of high speed, choosing the right tool can cut high hardness materials. High speed cutting can borrow other things: it can only be used for sliding friction to help chips take away most of the cutting heat, so as to reduce the thermal deformation of parts

the above advantages can only be realized under appropriate processing conditions. If the processing conditions are not appropriate, it will affect the life of the tool, and even lead to more serious consequences

1. High speed machining tool path

the limiting factors of high speed milling tool path are listed as follows according to their importance:

(1) tools cannot collide with parts

(2) the cutting load must be within the limit load of the tool

(3) the residual material shall not be greater than the specified limit

(4) sudden changes in material removal rate should be avoided

(5) the cutting speed and acceleration must be within the capability range of the machine tool

(6) the cutting direction (forward milling/reverse milling) selected by the cutting customer should be kept constant

(7) sudden changes in cutting direction should be avoided

(8) minimize empty range movement

(9) the cutting time should be minimized

in the process of tool path preparation of actual parts, it is difficult to fully meet the above requirements. In fact, when machining parts with complex shapes, we can only try to meet these requirements, and we must first meet the more important requirements. There is also the problem of knife marks in high-speed machining in finish machining: due to the limitation of part shape, if you want to accommodate the cutting conditions, you will leave visible knife marks on the surface of the processed part. Although they can be eliminated by polishing, they go against the original intention of using high-speed machining. After rough machining and semi finish machining, cam users have many ways to modify the shape of parts, and tool marks can also be eliminated by subsequent finish machining

2. Programming ability

a good high-speed machining program can be executed quickly on the machine tool, but it takes a long time and a lot of energy to compile. In the field of single piece machining of mold manufacturing, it is very common for machine tools to stop because of waiting for machining procedures. If this pressure is imposed on cam users to make them produce tool paths faster, they will be forced to take shortcuts, and the program compiled will have problems. Even if the machine tool can continue to operate, its processing speed has been greatly reduced, so it is unwise to use the method of pressurizing cam users for high-speed machining. In order to obtain the best high-speed machining effect, it is necessary to provide sufficient cam capability to obtain high-quality machining procedures and ensure the full load operation of the machine tool. To this end, we can start from the following aspects:

(1) using CAM software with automatic high-speed machining function can reduce the workload of users to optimize the program

(we have reason to believe 2) using CAM software that can quickly calculate the tool path without overcut, the batch processing function can leave the calculation of complex programs at night

(3) use a high-performance computer and update the configuration frequently to ensure sufficient memory to improve operation efficiency

(4) ensure that each machine tool is equipped with enough cam programmers. Train machine tool operators to program processing directly in the workshop, so as to give full play to their processing skills