- 카테고리 없음2020. 2. 23. 02:09
The tolerance of size is normally defined as the difference between the upper and lower dimensions.The need for tolerances to be identified on drawings is vital to allow assembly of parts in the desired way and interchangeability of parts as require in modern manufacturing methods.ISO 286 implements 20 grades of accuracy to satisfy the requirements of different industries. IT01, IT0, IT1, IT2, IT3, IT4, IT5, IT6. Production of gauges and instruments. IT 5, IT6, IT7, IT8, I9, IT10, IT11, IT12.Precision and general Industry.
Iso 2768-1
IT11, IT14, IT15, IT16.Semi finished products. IT16, IT17, IT18.Structural Engineeringtolerance band in micrometres = (m -6)based on ISO 286 IT Grades 1 to 14Nominal Sizes (mm)over50inc.0315IT Grade10.8111.21.51.522.21.51.5783300.
Din Iso 2768 Hole Tolerance
Iso 2768 Hole Tolerance
General Tolerances ISO 2768-1 ISO 2768-1 is intended to simplify drawing indications and specifies general tolerances in 4 tolerance classes (f – fine, m – medium, c – coarse, v – very coarse). It applies for the linear dimensions and angular dimensions such as external sizes, internal sizes, step sizes. General tolerance ISO 2768 does not specify where to use these tolerances. Tolerance class is defined as per design requirements and manufacturing capability. For example: for sheet metal parts ISO 2768–mk is used. And for machined components ISO 2768–fh can be used. ISO 2768-2: 1989, General tolerances — Part 2. H7/h6 is a very common standard tolerance which gives a tight fit. The tolerances work in such a way that for a hole H7 means that the hole should be made slightly larger than the base dimension (in this case for an ISO fit 10+0.015−0, meaning that it may be up to 0.015 mm larger than the base dimension, and 0 mm smaller). For example, a drawing could be specified as ISO 2768-mK, which means it should meet the tolerances ranges for “medium” from Part 1 and tolerance class “K” from Part 2. By including the ISO 2768 specification, you are simplifying your drawing, and avoiding writing tolerances for every dimension and feature.