# Tri-clamp × female NPT adapters (22MP style): ½ to 4 in

> How long is a tri-clamp to female NPT adapter?

- Category: Hardware › Sanitary clamp fittings
- Kind: Standard part
- Basis: Face-to-end A per Dixon T22MP; tap drill and L2 per ASME B1.20.1; body Ø the larger of the tube and the Class 3000 coupling OD (Xem Studio drawing)
- Page: https://xemstudio.com/objects/tri-clamp-female-npt-adapters/ · JSON: https://xemstudio.com/api/geometry?object=tri-clamp-female-npt-adapters · Plain text: https://xemstudio.com/objects/tri-clamp-female-npt-adapters/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); linked files under their publishers' licenses
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

**Exact dimensions.** True size, with no printing tolerance added.

## Notes

- Clamp face one end, a female pipe thread the other, drawn as the tap-drill bore over L2 + 2 so it can be tapped. Only sizes with a published A are drawn.
- Every clamp face is the ISO 2852 profile used across this site: 2.85 mm rim, flat face with the gasket groove (K 1.6 deep, R3 1.2 bottom, 23° walls, P2 0.8 edges) on C2, 20° back cone. Flange C3 / groove C2 / tube OD × wall, mm: ½–¾ in 25.0 / 20.4 (derived) / 12.7–19.05 × 1.65; 1–1½ in 50.5 / 43.5 / 25.4–38.1 × 1.65; 2 in 64.0 / 56.5 / 50.8 × 1.65; 2½ in 77.5 / 70.5 / 63.5 × 1.65; 3 in 91.0 / 83.5 / 76.2 × 1.65; 4 in 119.0 / 110.0 / 101.6 × 2.11; 6 in 166.9 (6.570 in) / 156.5 / 152.4 × 2.77; 8 in 217.7 (8.570 in) / 207.0 / 203.2 × 2.77; 10 in 268.5 / 261.0 / 254.0 × 3.40; 12 in 319.3 / 311.8 / 304.8 × 3.40.

## Sizes

| clamp_in | npt | A_in | A_mm | tap_drill_mm | L2_mm |
|---|---|---|---|---|---|
| ½ | ⅛ | 1.25 | 31.8 | 8.6 | 6.7 |
| ½ | ¼ | 1.5 | 38.1 | 11.1 | 10.2 |
| ½ | ¾ | 1.63 | 41.4 | 23.4 | 13.9 |
| ¾ | ¼ | 1.5 | 38.1 | 11.1 | 10.2 |
| ¾ | ¾ | 1.63 | 41.4 | 23.4 | 13.9 |
| 1½ | 1½ | 2.25 | 57.1 | 44.0 | 18.38 |
| 2 | 2 | 2.34 | 59.4 | 56.4 | 19.22 |
| 2½ | 2½ | 2.09 | 53.1 | 66.7 | 28.89 |
| 3 | 3 | 2.19 | 55.6 | 82.6 | 30.48 |
| 4 | 4 | 2.63 | 66.8 | 108.0 | 33.02 |

## Where the files are

- Dixon: [Clamp × male NPT (T21MP) and clamp × female NPT (T22MP) adapters: A per size](https://api.dixonvalve.com/en/media/1490003) — PDF — publisher's catalogue; dimensions cited
- ASME: [B1.20.1 Pipe threads, general purpose (NPT): major diameter, L2, tap drill; B16.11 forged fittings (Class 3000 couplings); B36.10 Sch 40 bore](https://www.asme.org/codes-standards/find-codes-standards/b1-20-1-pipe-threads-general-purpose-inch) — standard — ASME; dimensions are facts (verify at link)
- Rubber Fab: [Tri-Clamp gasket dimensional chart: gasket ID, OD and bead diameter per size (2 in bead 2.22 in / 56.50 mm, 1.5 in 1.71 / 43.50, 3 in 3.29 / 83.50)](https://shop.andersonprocess.com/media/assets/product/documents/rubber-fab-tri-clamp-dimensions.pdf) — PDF — maker chart; dimensions are facts (verify at link)

## Free STEP/STL (10 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/index.json

- female-npt-0.5in-x-1-8: [STEP](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-0.5in-x-1-8.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-0.5in-x-1-8.stl) — ½ in clamp × ⅛ FNPT: 1.25 in face to end; tap-drill bore Ø8.6 × 8.7
- female-npt-0.5in-x-1-4: [STEP](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-0.5in-x-1-4.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-0.5in-x-1-4.stl) — ½ in clamp × ¼ FNPT: 1.5 in face to end; tap-drill bore Ø11.1 × 12.2
- female-npt-0.5in-x-3-4: [STEP](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-0.5in-x-3-4.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-0.5in-x-3-4.stl) — ½ in clamp × ¾ FNPT: 1.63 in face to end; tap-drill bore Ø23.4 × 15.9
- female-npt-0.75in-x-1-4: [STEP](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-0.75in-x-1-4.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-0.75in-x-1-4.stl) — ¾ in clamp × ¼ FNPT: 1.5 in face to end; tap-drill bore Ø11.1 × 12.2
- female-npt-0.75in-x-3-4: [STEP](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-0.75in-x-3-4.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-0.75in-x-3-4.stl) — ¾ in clamp × ¾ FNPT: 1.63 in face to end; tap-drill bore Ø23.4 × 15.9
- female-npt-1.5in-x-1-1-2: [STEP](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-1.5in-x-1-1-2.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-1.5in-x-1-1-2.stl) — 1½ in clamp × 1½ FNPT: 2.25 in face to end; tap-drill bore Ø44.0 × 20.4
- female-npt-2in-x-2: [STEP](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-2in-x-2.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-2in-x-2.stl) — 2 in clamp × 2 FNPT: 2.34 in face to end; tap-drill bore Ø56.4 × 21.2
- female-npt-2.5in-x-2-1-2: [STEP](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-2.5in-x-2-1-2.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-2.5in-x-2-1-2.stl) — 2½ in clamp × 2½ FNPT: 2.09 in face to end; tap-drill bore Ø66.7 × 30.9
- female-npt-3in-x-3: [STEP](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-3in-x-3.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-3in-x-3.stl) — 3 in clamp × 3 FNPT: 2.19 in face to end; tap-drill bore Ø82.6 × 32.5
- female-npt-4in-x-4: [STEP](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-4in-x-4.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-female-npt-adapters/female-npt-4in-x-4.stl) — 4 in clamp × 4 FNPT: 2.63 in face to end; tap-drill bore Ø108.0 × 35.0

## Questions

**How long is a 1½ in tri-clamp × 1½ in FNPT adapter?**

2.25 in (57.2 mm) face to end.

## Fits with

- [Tri-clamp × male NPT adapters (21MP style): ½ to 4 in](https://xemstudio.com/objects/tri-clamp-male-npt-adapters/)
- [Tri-clamp end caps with ports: NPT, clamp nozzle, hose barb and airlock hole, 1½ to 8 in](https://xemstudio.com/objects/tri-clamp-ported-end-caps/)
- [Tri-clamp × hose barb adapters (14MPHR style): ½ to 4 in clamp, ¼ to 4 in hose](https://xemstudio.com/objects/tri-clamp-hose-barb-adapters/)