How to select measuring machine materials

How to select measuring machine materials?

Measuring machine with other precision measuring instruments, their use of materials and there is no absolute good or bad. Only by fully understanding the use of environment measuring machine, measuring the efficiency requirements and the physical properties of various materials, combined with excellent design and measurement systems design in order to carry out the choice of materials science and physical properties of materials to give full play to meet measurement requirements.

First, select the relevant materials with the measuring machine parameters:

1 Temperature characteristics:

As a high-precision measuring machine measuring devices in order to maintain its ongoing accuracy, the need for the installation environment for the appropriate response to temperature changes or compensation, which constitute the main components of the measuring machine temperature characteristics of the material becomes a items are very important indicators.

Assessment of the temperature characteristics of materials, we mainly from the thermal expansion coefficient, thermal conductivity, thermal expansion coefficient / thermal conductivity of the three main parameters for analysis.

* For general-purpose measuring machine, the machine requires relatively relaxed conditions to maintain a high temperature accuracy (plus or minus 2 degrees in the basic requirements, but many machines can work in a wider temperature environment). In this case, often uneven temperature changes and the impact (through the local and cumulative deformation) than the material impact of uniform expansion. Thermal expansion coefficient of expansion can be caused by simple temperature compensation technology is effectively compensated, but the accumulation of material deformation and partial compensation is very difficult and difficult to accurately compensated. So the universal measuring machine, to ensure expansion coefficient / thermal conductivity than the premise, it should be more focused on the thermal conductivity, combined with the back we have to discuss the operational characteristics and process characteristics, aluminum is the industry's best economic use the best materials.

* For a very good located in high-precision temperature environment within the machine, the machine is more emphasis on accuracy, and to achieve ultra-high precision and the means to ensure the use of more expensive high temperature environmental requirements (eg requirements to ensure that 0.5 degrees) and as small as possible unit expansion. Therefore, the choice of materials should be in a lower expansion coefficient / thermal conductivity than the material of the premise, more focused on the thermal expansion coefficient (better materials such as granite, ceramic).

(2) motion characteristics:

Continue to improve its efficiency is one of the most modern manufacturing salient features, and measurement systems are widely used on the shop floor, the manufacturing processes required to provide a faster real-time measurement feedback, therefore, the movement of the performance measurement system not only by providing more stable and smooth movement characteristics to enhance the measurement accuracy and repeatability, while providing higher measurement speed and efficiency. Motion characteristics of the measurement system is a need to focus on accuracy than the other indicators.

* The compensation technique is widely used after the coordinate measuring machine, rigidity has been the reference material properties are not the most important indicator, because the material of the static deformation and low-speed / acceleration compensation in case of deformation has become the mainstream standard coordinate measuring machine manufacturers means. The rigidity of the most complex - and the machine from the deformation of a high speed / acceleration run-time deformation and motion control error (by the machine, transmission, motion control system and other position loop). This case the weight of moving parts (reflected in the density of the material properties) is extremely important, its impact on the accuracy of the system but the series is not a simple multiple of the relationship.

* For general-purpose measuring machine, the user maximize the benefits of design ideas under the guidance of the machine need to ensure high accuracy, while the pursuit of greater efficiency. Therefore, the choice of materials should be at a higher stiffness / density ratio of the premise, more focused light on the material density, and by optimizing the structural design to reduce the quality of the moving parts. In this case, the advantages of aluminum and more clearly reflected. This is why the same accuracy of the machine, some companies can be more efficient to run the machine, other companies can only slow measurements. Inefficient means to invest more funds to purchase equipment and pay more measured labor and resources to take a longer time.

For high-precision measuring machine (less than 1 micron precision), the machine is more emphasis on accuracy more than speed. Therefore, material selection is often at a higher stiffness / density ratio of the premise, focus more on the rigidity of the material itself, or by increasing the size of materials to improve the overall rigidity. Both are effective methods used in the industry.

Undo edits

3 process and flexibility:

With the coordinate measuring machine of the growing demand, requires measuring machine manufacturing and production from the original production model into a single more efficient mass production, product quality and thus more stable, more efficient manufacturing, for customers provide a better cost-effective measurement products. In this context, the main components of the material measuring machine manufacturing process of a measuring machine manufacturers need to consider key indicators.

 

Second, how to choose the measuring machine materials:

More comprehensive analysis of the measuring machine in the main materials used (aluminum, ceramic, granite, steel) in the temperature characteristics, dynamic characteristics and process characteristics of the area on the basis of the relevant parameters, taking into account the measuring machine used in manufacturing today characteristics, use of the environment, accuracy and efficiency requirements, we can see:

1 Universal and workshop-type measuring machine:

Such a high precision measuring machine to ensure the case, the measurement of efficiency for a higher, in their work environment in general. In general, the aluminum measuring machine is ideal design of such materials.

Specifically as follows:

1.1 In the case of ambient temperature changes, due to large temperature changes outside, in both the coefficient of expansion / thermal conductivity than in the case, we need a better thermal conductivity of the material, in this regard, aluminum is the best material.

1.2 ensure that the material stiffness / density ratio at the same time, aluminum density, to ensure accuracy in the case of help to improve the dynamic performance measuring machine, to improve measurement efficiency. In particular aluminum alloy beam together with high precision triangular design, to fully tap the aluminum alloy material excellent properties of this ideal, is a measure of machine design classics.

1.3 aluminum alloy material consistency is easy to implement, such as Global is the aluminum frame, this has the advantage of the temperature changes, the deformation of various parts of the same, easy to compensate. Otherwise, if the machine beams, Z-axis carriage and use of different materials, the amount of expansion when the temperature difference, leading to swelling deformation of the machine twist, this deformation is nonlinear, it is difficult to solve by temperature compensation.