BS ISO 5752:2021 pdf download.Metal valves for use in flanged pipe systems — Face-to-face and centre-to-face dimensions.
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. ISO and IEC maintain terminological databases for use in standardization at the following addresses: — ISO Online browsing platform: available at https:// www .org/ obp — IEC Electropedia: available at http:// www .electropedia .org/ 3.1 DN NPS nominal size alphanumeric designation of size for components of a pipework system, which is used for reference purposes, comprising the letters DN or NPS followed by a dimensionless number which is indirectly related to the physical size, (in millimetres for DN and in inches for NPS), of the bore or outside diameter of the end connections Note 1 to entry: The number following DN or NPS does not represent a measurable value and is not used for calculation purposes except where specified in a product standard. [SOURCE: ISO 6708:1995, 2.1, modified — The terms “nominal size” and “NPS” have been added, “NPS” has been integrated into the definition and the Note 2 to entry has been deleted.]
4 Dimensions and tolerances The basic series of FTF and CTF dimensions, expressed in millimetres, shall be as given in Table 1. Table 1 is a summary of the dimensions in Tables 2 to 19 giving the origin of each series and should be referred to when considering valve types not covered by this document. Each particular column does not necessarily include all the values of the relevant basic series. See Annex C for information as to the origin of each basic series. Tables 17 and 18 cover butterfly check or wafer check valves which are retained in the piping by bolting that spans the two adjacent flanges, however these valves may alternately be furnished with full end flanges. Check valves shown as ‘long pattern’ shall be furnished with full end flanges only. The face-to-face and centre-to-face dimensions, as appropriate for the types of valves covered by this document, shall be in accordance with Tables 2 to 19, and the tolerances shall be in accordance with Tables 20 and 21. Annex A includes additional information on face-to-face and centre-to-face dimensions where ring joint facing is used and shall be followed. Tolerances on FTF and CTF dimensions as shown in Figure 1 are given in Table 20. Both tolerances shall be fulfilled.BS ISO 5752 pdf download.