Do you know the classification of national standards for geometric accuracy testing of machining centers

GB Classification for Geometric Accuracy Testing of Machining Centers
The geometric accuracy of a machining center is an important indicator for measuring its machining accuracy and quality. In order to ensure that the performance and accuracy of the machining center meet national standards, a series of geometric accuracy tests are required. This article will introduce the classification of national standards for geometric accuracy testing of machining centers.

 

1、 Axis verticality
Axis verticality refers to the degree of verticality between the axes of a machining center. This includes the verticality between the spindle axis and the worktable, as well as the verticality between the coordinate axes. The accuracy of verticality directly affects the shape and dimensional accuracy of the machined parts.
2、 Straightness
Straightness inspection involves the straight-line motion accuracy of the coordinate axis. This includes the straightness of the guide rail, the straightness of the workbench, etc. The accuracy of straightness is crucial for ensuring the positioning accuracy and motion stability of the machining center.
3、 Flatness
The flatness inspection mainly focuses on the flatness of the workbench and other surfaces. The flatness of the workbench can affect the installation and machining accuracy of the workpiece, while the flatness of other planes may affect the movement of the tool and the machining quality.
4、 Coaxiality
Coaxiality refers to the degree to which the axis of a rotating component coincides with the reference axis, such as the coaxiality between the spindle and the tool holder. The accuracy of coaxiality is crucial for high-speed rotary machining and high-precision hole machining.
5、 Parallelism
Parallelism testing involves the parallel relationship between coordinate axes, such as the parallelism of the X, Y, and Z axes. The accuracy of parallelism ensures the coordination and accuracy of the movements of each axis during multi axis machining.
6、 Radial runout
Radial runout refers to the amount of runout of a rotating component in the radial direction, such as the radial runout of a spindle. Radial runout can affect the roughness and accuracy of the machined surface.
7、 Axial displacement
Axial displacement refers to the amount of movement of a rotating component in the axial direction, such as the axial displacement of a spindle. Axial movement may cause instability in tool position and affect machining accuracy.
8、 Positioning accuracy
Positioning accuracy refers to the accuracy of a machining center at a specified position, including positioning error and repeated positioning accuracy. This is particularly important for processing complex shapes and high-precision parts.
9、 Reverse difference
Reverse difference refers to the difference in error when moving in the positive and negative directions of the coordinate axis. A smaller reverse difference helps to improve the accuracy and stability of the machining center.
These classifications cover the main aspects of geometric accuracy testing for machining centers. By inspecting these items, the overall accuracy level of the machining center can be evaluated and whether it meets national standards and relevant technical requirements can be determined.
In practical inspection, professional measuring instruments and tools such as rulers, calipers, micrometers, laser interferometers, etc. are usually used to measure and evaluate various accuracy indicators. At the same time, it is necessary to choose appropriate inspection methods and standards based on the type, specifications, and usage requirements of the machining center.
It should be noted that different countries and regions may have different geometric accuracy inspection standards and methods, but the overall goal is to ensure that the machining center has high precision and reliable machining capabilities. Regular geometric accuracy inspection and maintenance can ensure the normal operation of the machining center and improve machining quality and efficiency.
In summary, the national standard classification for geometric accuracy inspection of machining centers includes axis verticality, straightness, flatness, coaxiality, parallelism, radial runout, axial displacement, positioning accuracy, and reverse difference. These classifications help to comprehensively evaluate the accuracy performance of machining centers and ensure that they meet the requirements of high-quality machining