ISO-K and ISO-F large vacuum flanges (ISO 1609): OD, bolt circle, hole count and diameter, centering ring lip, DN63 to DN630, + ISO-F bolt-pattern templates — dimension sheet Source: Xem Studio, https://xemstudio.com/objects/iso-k-iso-f-flanges-dn63-dn630/ (sheet CC BY 4.0) Basis: Kurt J. Lesker's ISO tables as reproduced in Cornell CLASSE technical notes, cross-checked against the sample pages of ISO 1609:1986; numbers for ISO-K and the centering ring, bolt-pattern templates for ISO-F as files Catalog version: 2026-10-20 Overall (mm): length 750.0, width 750.0, height 6.0 - ISO-K and ISO-F (also LF, 'large flange', or ISO 1609) are the large vacuum flanges: ISO-K flanges are joined with clamps and ISO-F flanges with bolts through holes on a bolt circle. Both use a centering ring with an O-ring. Sizes are named by nominal bore in mm: 63, 80, 100, 160, 200, 250, 320, 400, 500, 630. - All values mm. ISO-F: flange OD, number of holes, hole diameter and bolt circle (BCD) are from the Lesker table (inches there, given with mm: 130 / 145 / 165 / 225 / 285 / 335 / 425 / 510 / 610 / 750 mm OD; BCD 110 / 125 / 145 / 200 / 260 / 310 / 395 / 480 / 580 / 720 mm; holes 4, 8, 8, 8, 12, 12, 12, 16, 16, 20; hole Ø 9, 9, 9, 11, 11, 11, 14, 14, 14, 14 mm; bolts M8 to M12 as printed '5/16 (M8)', '3/8 (M10)', '1/2 (M12)'). ISO-K flange OD is 95, 110, 130, 180, 240, 290, 370, 450, 550, 690 mm. - Cross-check against the standard: the OCR'd sample of ISO 1609:1986 (bolted flanges, nominal bore 200 to 1000, headers partly unreadable) repeats the same numbers for 200 to 630: 285 / 335 / 425 / 510 / 610 / 750 (outside diameter), 260 / 310 / 395 / 480 / 580 / 720 (bolt circle), 12 / 12 / 12 / 16 / 16 / 20 (holes), 240 / 290 / 370 / 450 / 550 / 690 (K flange OD) and 213 / 261 / 318 / 400 / 501 / 651 (centering ring lip OD). The sample's other columns (c, Y, D, M) cannot be assigned from the garbled headers and are not used, so hole diameter and bolt size above are Lesker's only. - Centering ring lip OD and ID (Lesker, mm): the lip OD fits the flange recess. ISO 1609 also gives 800 and 1000 bolted flanges and recommends 1250 to 2500; these are not on the Lesker table read and are not covered here. - Files: ISO-F bolt-pattern templates, one per size: a disc of the flange OD with the published hole count, hole diameter and bolt circle. Thickness (6 mm), the central aperture (half the bolt circle) and the position of the first hole (on +X) are Xem choices; the hole orientation relative to the sealing axis is not given by the sources. The collar, recess and sealing face are not modelled (no published numbers read). ISO-K clamp flanges are not drawn: their clamp seat is not dimensioned in the sources read. - Small flanges are on iso-kf-flanges-nw10-nw50 and knife-edge flanges on conflat-cf-flanges. McMaster-Carr's vacuum-fittings category is linked for per-part STEP. size ISO-K flange OD ISO-F flange OD ISO-F bolt circle ISO-F holes hole Ø bolt centering ring lip OD lip ID DN63 95 130 110 4 9 M8 (bolt 5/16 in) 70 66.8 DN80 110 145 125 8 9 M8 (bolt 5/16 in) 83 79.8 DN100 130 165 145 8 9 M8 (bolt 5/16 in) 102 98.8 DN160 180 225 200 8 11 M10 (bolt 3/8 in) 153 149.9 DN200 240 285 260 12 11 M10 (bolt 3/8 in) 213 209.8 DN250 290 335 310 12 11 M10 (bolt 3/8 in) 261 257.6 DN320 370 425 395 12 14 M12 (bolt 1/2 in) 318 312.4 DN400 450 510 480 16 14 M12 (bolt 1/2 in) 400 394.5 DN500 550 610 580 16 14 M12 (bolt 1/2 in) 501 495.6 DN630 690 750 720 20 14 M12 (bolt 1/2 in) 651 645.4 Files elsewhere (not hosted by Xem Studio; license as stated by the publisher): - Cornell CLASSE (technical notes, reproducing Kurt J. Lesker ISO tables): ISO flanges technical notes: ISO-F flange OD, holes, bolt circle, bolts; ISO-K flange OD; centering ring lip OD and ID, sizes 63 to 630 — web — Lab technical notes; numbers only — https://www.classe.cornell.edu/~dms79/D-lineNotes/components/ISO%20Flanges-TechnicalNotes.htm - ISO (iTeh preview): ISO 1609:1986 Vacuum technology - Flange dimensions (sample pages, OCR with garbled headers): bolted flange rows for nominal bores 200 to 1000 — web — Standard preview; numbers only; headers partly unreadable — https://cdn.standards.iteh.ai/samples/6209/2492d409536f44d6865afcbaaf717433/ISO-1609-1986.pdf - ANCORP (catalogue): ISO quick flange (QF/KF) and large flange (LF) centering rings: ID cross-reference, A and B dimensions in inches (stainless and aluminium centering ring assemblies) — web — Maker catalogue; numbers only — https://future4200.com/uploads/short-url/aRKA89A8sSu693NTJW9PFqCukFa.pdf - Kurt J. Lesker (catalogue, extracted text): Flanges, fittings and components: CF fixed flange standard dimensions (bolts, hole diameter, tapped thread, bolt circle); size lists for KF 1-4 and ISO 1-5 — web — Maker catalogue copy; numbers only. Column letters were not labelled in the extracted text — https://www.acomee.com.mx/catalogos/catalogosk/KURT-J-LESKER FLANGES, FITTINGS AND COMPONENTS.pdf - McMaster-Carr: Vacuum fittings (KF / ISO flanges) (free STEP/IGES per part, for your own design use; no redistribution) — STEP, IGES, PDF — McMaster-Carr site terms: personal design use, no redistribution [verify license at link] — https://www.mcmaster.com/products/vacuum-fittings/ No true-size file yet: the published figures do not fix the whole shape; a measured scan is planned. API: https://xemstudio.com/api/geometry?object=iso-k-iso-f-flanges-dn63-dn630