BS ISO 1609:2020 pdf download – Vacuum technology — Dimensions of non-knife edge flanges
1 Scope
This document specifies the dimensions of non-knife-edge flanges and collars used in vacuum technology.
The dimensions ensure interchangeability between bolted, clamped and rotatable flanges:
a) whether the assembly be homogeneous (for example, bolted flanges or clamped flanges) or heterogeneous (for example, bolted flanges assembled with clamped flanges either by means of bolts or clamps or by means of bolts and rotatable flanges).
b) whether the sealing rings used with the flanges be elastomer O-rings or metal sealing rings,provided that they are compatible with the linear sealing loads given in Annex A.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
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nominal bore
value intended to both identify the flange and specify the largest practical size of tubing that can be accommodated by the flange
[SOURCE: ISO 3669:2017, 3.2]
Note 1 to entry: The tables provide a series of nominal bores intended to identify the flanges or collars.
Note 2 to entry: These values follow the progression of the R10 series of preferred numbers (see ISO 3) from which only the term 12,5 has been eliminated.
Note 3 to entry: The values of nominal bore belonging to the R5 series of preferred numbers (see ISO 3) are as follows: 10, 16, 25, 40, 63, 100, 160, 250, 400, 630 and 1 000. They correspond to values intended to permit, in the long term, the adoption of a reduced series of nominal bores.
Note 4 to entry: The nominal bores 63 and 160 given in Tables 1, 2 and 3 correspond to practical diameters of
70 mm (or 65 mm) and 153 mm respectively.
diameter of bolt holes
value for the diameter of bolt holes
Note 1 to entry: C is derived from the bolt diameters, D, as given in ISO 273.
the corresponding quick-release couplings specified in ISO 2861. Relevant dimensions and tolerances are specified in Annex B.
NOTE 1 The selection of materials shall be compatible with the requirements for flanges and collars used in vacuum technology and with the dimensions given in Tables 1, 2 and 3.
NOTE 2 In order to ensure the interchangeability of vacuum components, the flanges shall be aligned so that the bolt holes are spaced equidistantly about and off the symmetrical plane of the component.BS ISO 1609 pdf download.