How to choose coordinate measuring machine correct

2022-09-20
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How to choose coordinate measuring machines correctly the quality goal in manufacturing is to keep the production of parts consistent with the design requirements. However, maintaining the consistency of the production process requires the control of the manufacturing process. The most effective way to establish and maintain the consistency of the manufacturing process is to accurately measure the size of the workpiece, obtain the size information, analyze and feed back the data to the production process, so as to make it an effective tool to continuously improve the product quality

coordinate measuring machine is one of the most effective methods to measure and obtain dimensional data, because it can replace a variety of surface measurement tools and expensive combination gauges, and reduce the time required for complex measurement tasks from hours to minutes. The function of CMM is to quickly and accurately evaluate the size data in February 2014, and provide useful information about the production process status for the operator, which is very different from all manual measuring equipment. Next, we will introduce how to choose a coordinate measuring machine:

the coordinate measuring machine contacts the workpiece through a sensor called a probe, and the obtained data can be combined with the dimensional description of the workpiece or a workpiece feature (such as a hole). Through these dimensional descriptions, it is easier to determine whether the workpiece or feature is out of tolerance. This information also provides clues for correcting the abnormalities in the production process that cause out of tolerance

make coordinate measuring machines suitable for your application

if a coordinate measuring machine is exactly what you need for your work, how to choose the best one? The first thing to decide is which model of CMM to buy. According to the position of the probe on the measuring machine, there are three basic types: vertical, horizontal and portable

vertical coordinate measuring machine install the probe on the vertical arm. The accuracy of this kind of measuring machine is higher than that of horizontal measuring machine, because the bridge structure is more stable and there are fewer moving parts, which makes them have better rigidity and stability. The vertical coordinate measuring machine contains various dimensions, which can measure the pinion, engine box, and even the fuselage of commercial aircraft

the horizontal measuring machine installs the measuring head on the horizontal shaft. They are generally used to detect large workpieces, such as car bodies, with a medium level of accuracy

the portable measuring machine simplifies the measurement of workpieces and assemblies that cannot be moved to the measuring machine. The portable measuring machine can be installed on or even inside the workpieces or assemblies, which allows the measurement of internal space and allows users to help everyone with the measurement in the assembly, thus saving the time of moving, transporting and measuring a single workpiece

in order to keep the CMM stable, in the design process, generally by improving the cross-section of structural components, increasing the distance between air bearings, improving the driving force of the motor, and optimizing the selection of structural materials based on the weight and temperature performance of 11.7% of which have structural defects, so as to increase the quality and rigidity, and improve the measurement accuracy, repeatability, measurement speed and acceleration. These principles are also applied to some horizontal workshop coordinate measuring machines. This system combines the flexibility of horizontal measuring machines with the high accuracy of vertical design

the direction of horizontal measurement makes the collocation of measuring machine and horizontal machine tool processing equipment more reasonable. They are especially suitable for measuring large gearboxes and engine housings that require high-precision measurements

the addition of turntable makes four axes possible, and the configuration of two arms can also be realized, which can measure all directions of the workpiece. The horizontal arm configuration is relatively easy to load and unload workpieces, and the small, workshop type horizontal arm measuring machine is suitable for high-speed production process

choose an appropriate instrument

CMM can be selected in two ways according to the application: manual and automatic. If you only need to detect workpieces with simple geometric quantities and tolerances, or measure various workpieces in small batches, manual instruments are the best choice. The software of the manual measuring machine can also store and call the measurement program, thus speeding up the repetitive measurement. If you need to detect a large number of the same workpiece, or require high accuracy, you should choose a measuring machine directly controlled by a computer. The numerical control measuring machine can automatically detect and eliminate the influence of the operator on the measurement results. Program driven means that high detection speed without error can be achieved

tolerance is also very important. It is difficult for manual measuring machines to meet smaller tolerance requirements, while CNC measuring machines make them more suitable for the high precision and high repeatability requirements of workpieces with strict tolerance requirements through their continuous touch measurement

CNC measuring machine is used to measure workpieces that require a large amount of data to define their geometric quantities by installing an analog scanning probe, such as the measurement of gears, cylinders, car bodies and windscreens. These probes can provide continuous data acquisition and reverse engineering from some workpieces and models for workpieces that are completely defined by arithmetic CAD or are completely unknown. For the workpiece with very small wheel profile, the scanning probe is an ideal choice because of its small scanning surface and requires a large amount of data to define

the installation site of the measuring machine is also very important. Ideally, the measuring machine should be installed as close as possible to the operator who manufactures the workpiece in the production process. These workshop type measuring machines generally have friendly user operation interfaces and control interfaces similar to machine tools

different types of measuring machines can work together. A measuring vertical measuring machine is generally used in the precision measuring room as the main arbitration of product performance. The working measuring machine is used in the production line to judge the quality of the workpiece, provide real-time statistical process control, and smoothly transition with the whole manufacturing process planning

the research and development investment is relatively high, and the key parts that need to be investigated

once you decide how and where to use the measuring machine, there are some key performances that need to be investigated, including measurement uncertainty and work efficiency. According to the current international standards, the uncertainty and detection procedure of the measuring machine are described in iso10360

iso10360 standard:

iso10360 mainly determines the following three errors:

a. the maximum allowable indication error mpee (iso10&nb) of length measurement

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