A complete analysis of the causes of tool collision in CNC machining centers

In the field of machine tool processing, the problem of tool collision is a major headache. Equipment tool collision may seem trivial, but it is actually very harmful. As a high-speed and high-precision automated precision equipment, the machining center will affect the processing efficiency at the least, and even cause the overall accuracy of the machining center to decrease, and even make the entire tool magazine become scrap. Therefore, in our daily processing, we must pay attention to the problem of tool collision. Understanding the cause of tool collision and taking precautions in advance are effective ways to reduce the occurrence of tool collision.

01 Human error of the operator

According to data statistics from the production line, most of the causes of tool collision in the machining center are caused by operator errors. For example, during the tool setting process, the speed of the machine tool drive shaft is too fast, resulting in tool collision; for example, the coordinate value of the machine tool axis is entered incorrectly, resulting in tool collision during the spindle processing. This is the most common cause of tool collision in the machining center.

Therefore, improving the professional quality and sense of responsibility of the operator of the machining center is the best way to prevent the machining center from hitting the tool, especially the sense of responsibility of the operator of the machining center, which is an absolute culprit.

In fact, the professional quality of the operator can be cultivated, because there are only a few commands and data back and forth. Anyone with relevant professional knowledge can master this skill in a short period of time, but the sense of responsibility of the operator is difficult to standardize.

In fact, in order to evade the responsibility of hitting the tool, many operators basically will not take the initiative to admit their operating errors. They all attribute the collision to the machine tool's own failure, and they also make plausible arguments and blame others. 

Even many people, including managers on the production line, believe that it is inevitable for the operator of the machining center to hit the tool. Just hit it a few more times. With experience, you will naturally not hit it. What kind of ghost logic is this, nonsense.

In fact, the damage to the machine tool caused by the collision of the machining center is very serious, especially the damage to the machining accuracy of the machine tool, which is basically irreversible damage, especially for some high-precision machine tools. After several collisions, the accuracy is basically lost. On the surface, there seems to be no significant change, but in fact, the accuracy of the machine tool is no longer there.

In addition, for many automatic processing production lines, there may be clamping errors caused by inaccurate positioning of parts. For example, when the robot places the part on the fixture, there is a deviation in the placement position, which leads to the inadequate clamping of the part. If there is no corresponding workpiece in place detection switch, the tool may collide with the tool during the feeding process.

And because the automatic production line is fully automated, the operator does not intervene in the processing of the machine tool during the processing, so it is difficult to manually find the problems caused by clamping, which further increases the probability of tool collision.

At the same time, during the processing of the machine tool, the wear and damage of the tool can easily cause the machine tool to collide with the tool. For example, the tool suddenly collapses or breaks, so that the tool loses its cutting force, but the feed of the machine tool does not stop. At this time, it is easy to cause a tool collision, so the feed load of the machine tool should be monitored in real time. If there is an abnormality, it should be able to stop the machine actively, so as to minimize the damage to the machine tool caused by the collision.

03 Machine tool motion failure

The so-called machine tool failure refers to the out-of-control state of the machine tool operating system. For example, when the machine tool is executing a processing program, its processing trajectory does not follow the trajectory of the processing program, but there is a large deviation. At this time, the machine tool will have a tool collision phenomenon. And such a tool collision is very scary. Suddenly, it is found that the cutting of the machine tool is abnormal. I have encountered it once. During the processing, a 20-meter end mill buried the tool and processed it. Sparks flew and abnormal noises shook the sky.

Later, it was detected that there was a problem with a certain motion module of the machine tool control system. Of course, such a situation is relatively rare, but there are many such excuses. Many operators use this reason as an excuse for their tool collision after their own operation errors, trying to evade responsibility and punishment, and this reason is also difficult to find.

Especially some domestic CNC systems, because these systems do have certain instability phenomena, which may occur once or twice a year, but it gives many people an excuse to "bump into porcelain".

Therefore, orderly, timely and professional operation and maintenance of processing equipment is a very important thing. Do not use processing equipment overloaded, otherwise it will definitely be more than worth the loss.

Therefore, we must try our best to avoid the collision of machine tools. There is not much difference between a machine tool collision and a car crashing into a wall. For mechanical equipment, both are suicidal behaviors.

02 Workpiece clamping failure

The second reason for machine tool collision is the failure of the clamping of the workpiece. For example, the workpiece is loose during the processing process, and the parts will move under the push of the tool cutting force. At this time, it is easy to cause a collision, and it is also easy to cause the workpiece to be thrown out of the fixture, or even break the door and window glass of the machine tool and other dangerous accidents.