# Tri-clamp (Tri-Clover) sanitary ferrule, 1/2 to 4 inch

> What are tri-clamp ferrule dimensions: flange OD, tube OD and which sizes share a clamp?

- Category: Hardware › Tri-clamp
- Kind: Hardware
- Basis: ISO 2852:1974 face profile (rim 2.85, recess 1.6, 20° back angle, groove diameters) with ASME BPE tube sizes; 16 ga wall
- Page: https://xemstudio.com/objects/tri-clamp-ferrule/ · JSON: https://xemstudio.com/api/geometry?object=tri-clamp-ferrule · Plain text: https://xemstudio.com/objects/tri-clamp-ferrule/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); linked files under their publishers' licenses

## Notes

- Clamp size follows the flange OD, not the tube: 1/2 and 3/4 in share a 25.4 mm flange; 1 and 1.5 in share 50.5 mm; 2 in is 64.0; 2.5 in 77.5; 3 in 91.0; 4 in 119.0 mm.
- Face (ISO 2852 §6.1): a flat sealing land from the groove diameter C2 out to the rim, and a recess 1.6 mm deep (K) from C2 in to the bore, where the gasket bead sits. C2 = 43.5 mm for the 50.5 flange, 56.5 for 64.0, 83.5 for 91.0. Radii R2 2.0 / R3 1.2 mm.
- Rim thickness L1 = 2.85 mm; the back of the flange is a 20° cone (α) rising to the hub, which is what the clamp's V-ring grips. Hub thickness works out to about 5.3 mm on a 2 in weld ferrule.
- Weld ferrules: 21.5 mm (ISO/short) or 28.6 mm (ASME BPE medium); 44.5 / 57.2 mm long versions exist. Tube end plain for a butt weld.
- Printing it: this profile prints true in PLA/PETG for mock-ups and clamp fit checks; the sealing land needs a smooth top layer. Real parts are 304/316 stainless.
- Why it matters here: a thermoacoustic/Stirling engine body built from 2 in tri-clamp parts is a stack of ferrules, spools and caps; print the stack first, then buy steel.

## Sizes

| nominal_in | tube_od_mm | tube_od_in | wall_mm | flange_od_mm | groove_dia_mm | clamp_size |
|---|---|---|---|---|---|---|
| 1/2 | 12.7 | 0.5 | 1.65 | 25.4 | n/a in ISO sample | 1/2–3/4 |
| 3/4 | 19.05 | 0.75 | 1.65 | 25.4 | n/a in ISO sample | 1/2–3/4 |
| 1 | 25.4 | 1.0 | 1.65 | 50.5 | 43.5 | 1–1.5 |
| 1-1/2 | 38.1 | 1.5 | 1.65 | 50.5 | 43.5 | 1–1.5 |
| 2 | 50.8 | 2.0 | 1.65 | 64.0 | 56.5 | 2 |
| 2-1/2 | 63.5 | 2.5 | 1.65 | 77.5 | n/a in ISO sample | 2.5 |
| 3 | 76.2 | 3.0 | 1.65 | 91.0 | 83.5 | 3 |
| 4 | 101.6 | 4.0 | 2.11 | 119.0 | n/a in ISO sample | 4 |

## Where the files are

- ISO (via iTeh sample): [ISO 2852:1974 clamp liners with gaskets (face and gasket profile, §6.1 and §8)](https://cdn.standards.iteh.ai/samples/7850/eb49c396488d408c8ced3e2961d76cf3/ISO-2852-1974.pdf) — PDF — standard excerpt; dimensions are facts
- McMaster-Carr: [Sanitary (quick-clamp) tube fittings (free STEP per part, for your own design use; no redistribution)](https://www.mcmaster.com/products/sanitary-fittings/) — STEP, PDF — McMaster-Carr site terms: personal design use, no redistribution (verify at link)
- Dixon Valve: [Sanitary fittings catalog (dimensions)](https://www.dixonvalve.com/en/sanitary-fittings) — PDF — vendor catalog (verify at link)
- Wikipedia: [Tri-clamp fitting](https://en.wikipedia.org/wiki/Tri-clamp) — web — CC BY-SA 4.0 (text) (verify at link)
- Long Earth Society: [The engine built from tri-clamp parts](https://longearthsociety.com/engineering/custom-high-temp-stirling/) — web — CC BY 4.0 (text)

## Free STEP/STL (8 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/tri-clamp-ferrule/index.json

- tc-ferrule-1in-21.5mm: [STEP](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-1in-21.5mm.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-1in-21.5mm.stl) — 1 in weld ferrule, 21.5 mm, 16 ga; ISO 2852 face (2.85 rim, 1.6 recess, 20° back)
- tc-ferrule-1in-28.6mm: [STEP](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-1in-28.6mm.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-1in-28.6mm.stl) — 1 in weld ferrule, 28.6 mm, 16 ga; ISO 2852 face (2.85 rim, 1.6 recess, 20° back)
- tc-ferrule-1.5in-21.5mm: [STEP](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-1.5in-21.5mm.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-1.5in-21.5mm.stl) — 1.5 in weld ferrule, 21.5 mm, 16 ga; ISO 2852 face (2.85 rim, 1.6 recess, 20° back)
- tc-ferrule-1.5in-28.6mm: [STEP](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-1.5in-28.6mm.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-1.5in-28.6mm.stl) — 1.5 in weld ferrule, 28.6 mm, 16 ga; ISO 2852 face (2.85 rim, 1.6 recess, 20° back)
- tc-ferrule-2in-21.5mm: [STEP](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-2in-21.5mm.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-2in-21.5mm.stl) — 2 in weld ferrule, 21.5 mm, 16 ga; ISO 2852 face (2.85 rim, 1.6 recess, 20° back)
- tc-ferrule-2in-28.6mm: [STEP](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-2in-28.6mm.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-2in-28.6mm.stl) — 2 in weld ferrule, 28.6 mm, 16 ga; ISO 2852 face (2.85 rim, 1.6 recess, 20° back)
- tc-ferrule-3in-21.5mm: [STEP](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-3in-21.5mm.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-3in-21.5mm.stl) — 3 in weld ferrule, 21.5 mm, 16 ga; ISO 2852 face (2.85 rim, 1.6 recess, 20° back)
- tc-ferrule-3in-28.6mm: [STEP](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-3in-28.6mm.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-ferrule/tc-ferrule-3in-28.6mm.stl) — 3 in weld ferrule, 28.6 mm, 16 ga; ISO 2852 face (2.85 rim, 1.6 recess, 20° back)

## Questions

**What is the flange OD of a 2 inch tri clamp ferrule?**

64.0 mm. 1 in and 1.5 in share a 50.5 mm flange and the same clamp; 2.5 in is 77.5 mm; 3 in is 91.0 mm; 4 in is 119.0 mm.

**Are 1 inch and 1.5 inch tri clamp fittings interchangeable?**

The flanges are the same (50.5 mm OD, 43.5 mm groove) so a 1.5 in clamp and gasket fit both; the tube bores differ (25.4 vs 38.1 mm OD tube).

**What are the ISO 2852 tri clamp face dimensions?**

Rim thickness 2.85 mm, gasket recess 1.6 mm deep inside the groove diameter (43.5 / 56.5 / 83.5 mm for 50.5 / 64 / 91 flanges), 20° back cone that the clamp grips. The free STEP files here use exactly that profile.

**Can I 3D print a tri clamp ferrule?**

For mock-ups, fit checks and low-pressure air, yes: the STEP/STL here follow the ISO 2852 face so a real clamp and gasket seat on them. Not for pressure, heat or food service; print the stack, then buy stainless.

## Fits with

- [Tri-clamp spool (two ferrules on a tube), 1.5 and 2 inch](https://xemstudio.com/objects/tri-clamp-spool/)
- [Tri-clamp end cap and gasket, 1.5 and 2 inch](https://xemstudio.com/objects/tri-clamp-end-cap/)
- [Schedule 40 pipe and PVC fittings, 1/2 to 2 inch](https://xemstudio.com/objects/schedule-40-pipe/)
- [O-rings, common metric sizes (ISO 3601)](https://xemstudio.com/objects/o-rings-metric/)