ISO 1179 / BSPP (G thread) ports with O-ring or bonded seal: D3, D4, O-ring size, Dowty bonded-seal ID, OD, thickness — dimension sheet Source: Xem Studio, https://xemstudio.com/objects/iso-1179-bspp-ports-and-bonded-seals/ (sheet CC BY 4.0) Basis: Parker Tube Fittings Division catalog 4300 table U20 / T26 (ISO 1179-1), RS Components' bonded seals datasheet and TSS's GM500 self-centring tables; seven seal envelopes as files Catalog version: 2026-10-20 Overall (mm): length 38.1, width 38.1, height 2.47 - ISO 1179-1 is the flat-face port with ISO 228-1 'G' (BSPP, parallel) threads (Parker lists it with DIN 3852 part 2). Parker catalog 4300 prints it as table U20 (page U29; table T26 in another edition) for G 1/8-28 to G 2-11, with the headings Thread Size, D3, D4, L1 max, L2 min, then seal groups (type E elastic seal for narrow types B and E, and O-ring / retaining ring for wide types G and H), Parker O-ring size, O-ring ID × section (mm), bonded washer part number and retaining ring part number. In the text we could read, several of these headings were merged and the number columns did not line up with them (two renditions of the same table, from two editions, give the same numbers but place a few headings differently), so D3, D4, L1 and L2 are shown in the printed order with the one extra dimension column left unlabelled. Check the table in Parker's catalog before cutting a port from it. - The sealing options per thread are as printed: an O-ring (Parker 2-111 for G 1/4, 2-113 for G 3/8, 2-119 for G 3/4, 2-217, 2-222 and 2-224 for G 1 to G 1 1/2; 5-585 for G 1/8 and 5-256 for G 1/2, as read) with a retaining ring, or a bonded washer named by the thread (1/8, 1/4 and so on). G 2 has no O-ring or bonded washer listed. - Bonded seals (Dowty seals, bonded washers): a metal washer with a bonded rubber lip that seals under a plug or hex head on a flat face. RS Components' British-standard range prints size ref, ID d, OD D and thickness S (mm; d ±0.13, 'common standard BS 21 or ISO 228'); TSS's GM500 self-centring range, BSP inch table, prints OD, d3, ID, dN and t (letters not defined in the text). For G 1/8 to G 7/8 the two sources agree on ID, OD and thickness (10.37 / 15.88 / 2.00 for G 1/8, 13.74 / 20.57 / 2.00 for G 1/4, 17.28 / 23.80 / 2.00 for G 3/8, then 2.47 mm thick for G 1/2 to G 7/8); from G 1 up they agree on ID and OD but not on thickness (RS 2.34 to 3.25, TSS 3.40), so both are shown and no file is drawn for those. TSS's table also has 5/8 and 11/16 in rows that are not BSP threads and are left out. Size refs 020 to 039 are matched to the G threads by the shared ID / OD figures, since RS's thread column mixes several thread names in one cell. - Files: seven plain ring envelopes (ID × OD × thickness) for G 1/8, G 1/4, G 3/8, G 1/2, G 5/8, G 3/4 and G 7/8. They are envelopes of the washer, not its section: a bonded seal's metal and rubber profile is not published as numbers in the sources read. Thread major diameters for the G sizes are on npt-bsp-thread-envelopes (G 1/8 9.73, G 1/4 13.16, G 3/8 16.66, G 1/2 20.96, G 3/4 26.44, G 1 33.25 mm). - Metric bonded seals (M4 to M24, TSS Table XXVIII) and RS's German and French ranges are not on this page. Maker CAD: Parker's catalog pages and RS / TSS datasheets are linked as the source of the numbers; McMaster-Carr sells bonded sealing washers with per-part STEP but no link was read, so none is given. source thread (ISO 228-1) D3 D4 L1 max L2 min (5th column, heading merged) Parker O-ring (ID × section mm) bonded washer (Parker) retaining ring (Parker) seal ID / OD (mm) seal thickness (mm) other ISO 1179-1 port (Parker table, as read) G 1/8-28 9.9 15 17.2 1 8.5 5-585 (7.98 × 1.88) 1/8 (Parker part no.) D9DT-2 — — — ISO 1179-1 port (Parker table, as read) G 1/4-19 13.3 20 20.7 1.5 12.5 2-111 (10.77 × 2.62) 1/4 (Parker part no.) D9DT-4 — — — ISO 1179-1 port (Parker table, as read) G 3/8-19 16.8 23 24.5 2 12.5 2-113 (13.94 × 2.62) 3/8 (Parker part no.) D9DT-6 — — — ISO 1179-1 port (Parker table, as read) G 1/2-14 21.1 28 34 2.5 14.5 5-256 (17.96 × 2.62) 1/2 (Parker part no.) D9DT-8 — — — ISO 1179-1 port (Parker table, as read) G 3/4-14 26.6 33 40 2.5 16.5 2-119 (23.47 × 2.62) 3/4 (Parker part no.) D9DT-12 — — — ISO 1179-1 port (Parker table, as read) G 1-11 33.5 41 46.1 2.5 18.5 2-217 (29.74 × 3.53) 1 (Parker part no.) D9DT-16 — — — ISO 1179-1 port (Parker table, as read) G 1 1/4-11 42.2 51 54 2.5 20.5 2-222 (37.69 × 3.53) 1 1/4 (Parker part no.) D9DT-20 — — — ISO 1179-1 port (Parker table, as read) G 1 1/2-11 48.1 56 60.5 2.5 22.5 2-224 (44.04 × 3.53) 1 1/2 (Parker part no.) D9DT-24 — — — ISO 1179-1 port (Parker table, as read) G 2-11 59.9 69 73.3 3 26 — — D9DT-32 — — — Bonded seal (RS Components British standard / TSS GM500 self-centring) G 1/8 — — — — — — — — 10.37 / 15.88 2 (RS) ref 020; TSS d3 11.84, dN 8.26 Bonded seal (RS Components British standard / TSS GM500 self-centring) G 1/4 — — — — — — — — 13.74 / 20.57 2 (RS) ref 021; TSS d3 15.21, dN 11.18 Bonded seal (RS Components British standard / TSS GM500 self-centring) G 3/8 — — — — — — — — 17.28 / 23.80 2 (RS) ref 023; TSS d3 18.75, dN 14.76 Bonded seal (RS Components British standard / TSS GM500 self-centring) G 1/2 — — — — — — — — 21.54 / 28.58 2.47 (RS) ref 025; TSS d3 23.01, dN 18.24 Bonded seal (RS Components British standard / TSS GM500 self-centring) G 5/8 — — — — — — — — 23.49 / 31.75 2.47 (RS) ref 026; TSS d3 24.97, dN 20.27 Bonded seal (RS Components British standard / TSS GM500 self-centring) G 3/4 — — — — — — — — 27.05 / 34.93 2.47 (RS) ref 027; TSS d3 28.53, dN 23.83 Bonded seal (RS Components British standard / TSS GM500 self-centring) G 7/8 — — — — — — — — 30.81 / 38.10 2.47 (RS) ref 029; TSS d3 32.29, dN 27.51 Bonded seal (RS Components British standard / TSS GM500 self-centring) G 1 — — — — — — — — 33.89 / 42.80 2.34 (RS) / 3.4 (TSS) ref 030; TSS d3 36.88, dN 29.92 Bonded seal (RS Components British standard / TSS GM500 self-centring) G 1 1/4 — — — — — — — — 42.93 / 52.38 2.5 (RS) / 3.4 (TSS) ref 032; TSS d3 45.93, dN 38.45 Bonded seal (RS Components British standard / TSS GM500 self-centring) G 1 1/2 — — — — — — — — 48.44 / 58.60 2.5 (RS) / 3.4 (TSS) ref 033; TSS d3 51.39, dN 44.45 Bonded seal (RS Components British standard / TSS GM500 self-centring) G 1 3/4 — — — — — — — — 54.89 / 69.85 3.25 (RS) / 3.4 (TSS) ref 034; TSS d3 58.30, dN 50.42 Bonded seal (RS Components British standard / TSS GM500 self-centring) G 2 — — — — — — — — 60.58 / 73.03 3.25 (RS) / 3.4 (TSS) ref 036; TSS d3 63.63, dN 56.26 Bonded seal (RS Components British standard / TSS GM500 self-centring) G 2 1/4 — — — — — — — — 66.68 / 79.50 3.25 (RS) / 3.4 (TSS) ref 038; TSS d3 69.98, dN 62.36 Bonded seal (RS Components British standard / TSS GM500 self-centring) G 2 1/2 — — — — — — — — 76.08 / 90.17 3.25 (RS) / 3.4 (TSS) ref 039; TSS d3 79.38, dN 71.50 Files elsewhere (not hosted by Xem Studio; license as stated by the publisher): - Parker Tube Fittings Division (4300 catalog, pages U29 / T36): Table U20 (T26 in another edition): Port detail, ISO 1179-1 flat face port with BSPP threads (DIN 3852 part 2) — web — Maker catalog page; numbers only. Column alignment merged in the text read — https://www.goodyearrubberproducts.com/files/Parker/ParkerTubeCatalog4300/Parker%20Tube%20Catalog%204300examin1.Page480.pdf - Parker Tube Fittings Division (4300 catalog, same table, another edition, hosted by Hydradyne): Table T26: Port detail, ISO 1179-1 — web — Maker catalog page; numbers only — https://www.hydradynellc.com/images/document/159_iso%201179.pdf - RS Components (bonded seals datasheet): British imperial standard bonded seals: size ref, ID d, OD D, thickness S (mm) — web — Distributor datasheet; numbers only — https://docs.rs-online.com/1729/A700000015227694.pdf - TSS Sealing (BONDED-SEALS catalogue, hosted by SEAuto): GM500 self-centring bonded seals, BSP inch range (Table XXIX) and metric range (Table XXVIII): OD, d3, ID, dN, t — web — Maker catalogue; numbers only — https://www.seauto.es/wp-content/uploads/2022/05/BONDED-SEALS.pdf - Parker Tube Fittings Division (hosted by Wilson Company): O-rings and seals: ORFS, SAE boss, ISO 6149, SAE 4-bolt flange O-ring sizes (ID, W) — web — Maker catalog pages; numbers only — https://wilson-company.com/images/document/TFD/O-Rings___Seals.pdf Free files (CC BY 4.0, Xem Studio; STEP + STL, 7 parts): https://xemstudio.com/files/hardware/iso-1179-bspp-ports-and-bonded-seals/index.json API: https://xemstudio.com/api/geometry?object=iso-1179-bspp-ports-and-bonded-seals