Machining emphasizes that machining must meet certain precision, which means that the main parameters of the actual geometric figure of the steel parts after machining are consistent with the ideal values required by the part drawings. The inconsistent level among them is called production and processing deviation.
The machining production precision includes three levels: on the one hand, it is the specification precision, which limits the specification deviation between the two standards of the production and processing surface to not exceed the necessary scope; On the other hand, the geometric figure appearance precision limits the macroeconomic geometric figure appearance deviation of the production and processing surface, such as roundness, cylindricity, parallelism and straightness.
On the other hand, it is the mutual position precision, which limits the mutual position deviation between the two standards of the production and processing surface of the machining plant, such as the axis, flatness and parallelism. Production and processing precision refers to the conformity between the actual specifications, appearance and main parameters of several geometric figures of parts surface after production and processing and the main parameters of ideal geometric figures specified in engineering drawings.
The main parameters of the idealized geometric figure refer to the mean value specification; In terms of surface geometry, it refers to circles, cylinders, plans, spheres and parallel lines; For the mutual parts in the middle of the surface layer, it refers to the parallel plane, vertical, coaxial output, symmetry, etc.
The deviation between the main parameters of the actual geometry and the main parameters of the idealized geometry of machined production parts is called production processing deviation. Production processing precision and production processing deviation are all terms used to comment on the main parameters of the surface geometric figure of production processing. The precision of production and processing is considered by tolerance grade. The smaller the grade value, the higher the precision; The production and processing deviation is expressed by a standard value. The larger the standard value, the greater the deviation.
