How to ensure the quality of CMM measuring needle?

How to ensure the quality of CMM measuring needle?

The tip of a CMM needle is usually a sphere made of artificial ruby. The most commonly used sphere-measuring indicators are level 5 and level 10. Of course, the lower the level, the better the ball. The selection of CMM materials is related to scanning applications. For example, in industry, probe needles in silicon nitride materials are often used to scan aluminum or cast iron materials to avoid "adhesion damage" from material interactions on the surface of ruby test balls. In addition, the choice of measuring rod material is also very important.

The measuring rod must be designed for maximum stiffness so that even if the rod is bent to the lowest point, it will not break. In addition to the stainless steel commonly used in the market, tungsten carbide rods with small diameter or very long rods are also a good choice. When choosing a coordinate measuring needle, we can choose the shortest measuring needle as possible. The longer the measuring needle, the lower the accuracy; Also reduce the number of needle combinations; Also choose to measure the diameter of the ball as large as possible needle; This can not only increase the distance between the measuring ball and the measuring needle rod, but also reduce the collision of the measuring needle rod. Finally, when measuring needle combinations, the maximum allowable range of measuring needle length and weight specified by the measuring needle manufacturer should also be considered.

In modern manufacturing process, CMM is an indispensable testing tool to ensure product quality and improve product accuracy. The specific operation of CMM is a measuring instrument that transmits data back to the computer software for processing according to the measurement data of measuring head in the established three-dimensional space. So what is the purpose of using a CMM to correct the ball?

Calibration ball is an important structural component of CMM, which provides accurate data for product measurement. Only by correcting the measuring head of CMM before measurement can we ensure that more accurate data can be obtained in the testing of future products.

It can be seen that the use of CMM calibration ball is an important step before the formal operation of the whole measuring instrument measurement, can not be ignored. If the CMM is not accurately calibrated before use, the measured value is deviated from the imagined value. In addition, in order to make the measuring head more accurate, the calibration ball should be kept clean to avoid measurement errors. If the correction ball is damaged or worn, it will affect the calibration of the measuring head and thus affect the accuracy of the next measurement, so once the correction ball is damaged, it should be replaced immediately.