# Bellows couplings (GN 2244 and common sizes): outside diameter, length, clamp screw, rated torque, misalignment

> What are the sizes of a bellows shaft coupling (19 mm, 25 mm, 27 mm, 32 mm, 40 mm): outside diameter, length, clamp screw, rated torque and misalignment?

- Category: Hardware › Bearings, rails & motion
- Kind: Standard part
- Basis: Ganter GN 2244 table via Digi-Key; McMaster-Carr bellows coupling sizes as a second list; McMaster-Carr linked for CAD
- Page: https://xemstudio.com/objects/bellows-couplings/ · JSON: https://xemstudio.com/api/geometry?object=bellows-couplings · Plain text: https://xemstudio.com/objects/bellows-couplings/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's license
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

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

## Notes

- A bellows coupling joins two shafts through a thin-walled metal bellows between two clamp hubs: it is torsionally stiff with no backlash (good for encoders, lead screws and servo/stepper drives) and takes small misalignment, but it is fragile in bending and shock. Hubs clamp with one screw or two; the bore combinations are chosen per order.
- Numbers: Ganter GN 2244 (aluminium hubs, stainless bellows) via Digi-Key, four sizes with outside Ø 19, 27, 32 and 40 mm: lengths l1 30 / 35 / 46 / 51, clamp screws M2 / M2.5 / M3 / M4 with tightening torques 0.5 / 0.9 / 1.5 / 3.5 Nm, rated torques 1.5 / 2.3 / 4.5 / 10 Nm, maximum speeds 33000 / 23000 / 19000 / 15000 rpm; lateral misalignment 0.15 / 0.15 / 0.2 / 0.2 mm, axial ±0.5 / ±0.5 / ±0.7 / ±1 mm, angular 1.5°. The l2, l3, l4 letters are the maker's drawing letters and are not interpreted. Standard bore combinations are in the maker's table and are not reproduced here.
- McMaster-Carr lists bellows couplings (aluminium and 321 stainless) at outside Ø × length of 15 × 27.3, 19.1 × 33.2, 25.4 × 34.2, 33.3 × 43.2, 41.3 × 51.7, 50.8 × 61.3 and 57.2 × 82.2 mm; they are included as a second, independent size list: for the 19 mm size Ganter's 30 against McMaster's 33.2 for a 19.1 mm part shows that lengths differ between makers, so the two are shown side by side, never merged.
- Files: none. The bellows convolutions are not dimensioned in the tables.
- Left out: bore lists, torsional stiffness, double-bellows couplings, set-screw hubs, weights.

## Sizes

| size | outside Ø d1, mm | length l1, mm | l2, mm | l3, mm | l4, mm | clamp screw | screw tightening torque, Nm | rated torque, Nm | max speed, rpm | lateral misalignment, mm | axial, mm | angular |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| GN 2244, d1 19 | Ø19 | 30 | 10.5 | 3 | 6.8 | M2 | 0.5 | 1.5 | 33000 | 0.15 | ±0.5 | 1.5° |
| GN 2244, d1 27 | Ø27 | 35 | 12.5 | 3.5 | 10.3 | M2.5 | 0.9 | 2.3 | 23000 | 0.15 | ±0.5 | 1.5° |
| GN 2244, d1 32 | Ø32 | 46 | 15.5 | 4.3 | 12 | M3 | 1.5 | 4.5 | 19000 | 0.2 | ±0.7 | 1.5° |
| GN 2244, d1 40 | Ø40 | 51 | 16 | 5 | 15 | M4 | 3.5 | 10 | 15000 | 0.2 | ±1 | 1.5° |
| Ø15 × 27.3 (McMaster-listed aluminium / 321 SS bellows coupling, outside Ø × length) | — | — | — | — | — | — | — | — | — | — | — | — |
| Ø19.1 × 33.2 (McMaster-listed aluminium / 321 SS bellows coupling, outside Ø × length) | — | — | — | — | — | — | — | — | — | — | — | — |
| Ø25.4 × 34.2 (McMaster-listed aluminium / 321 SS bellows coupling, outside Ø × length) | — | — | — | — | — | — | — | — | — | — | — | — |
| Ø33.3 × 43.2 (McMaster-listed aluminium / 321 SS bellows coupling, outside Ø × length) | — | — | — | — | — | — | — | — | — | — | — | — |
| Ø41.3 × 51.7 (McMaster-listed aluminium / 321 SS bellows coupling, outside Ø × length) | — | — | — | — | — | — | — | — | — | — | — | — |
| Ø50.8 × 61.3 (McMaster-listed aluminium / 321 SS bellows coupling, outside Ø × length) | — | — | — | — | — | — | — | — | — | — | — | — |
| Ø57.2 × 82.2 (McMaster-listed aluminium / 321 SS bellows coupling, outside Ø × length) | — | — | — | — | — | — | — | — | — | — | — | — |

## Where the files are

- Ganter / Digi-Key data sheet GN 2244: [Bellows couplings GN 2244: d1 outside diameter, bore combinations, clamping screw d4, l1 to l4, torque, speed, misalignment](https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/4017/2244.pdf) — web — Publisher's page; dimensions are facts
- McMaster-Carr: [Bellows shaft couplings (free STEP/IGES per part, for your own design use; no redistribution)](https://www.mcmaster.com/bellows-shaft-couplings) — STEP, IGES, PDF — McMaster-Carr site terms: personal design use, no redistribution (verify at link)

## Questions

**What size is a 19 mm bellows coupling?**

Outside Ø19, length 30, M2 clamp screw (0.5 Nm), rated torque 1.5 Nm, 33000 rpm (Ganter GN 2244).

**What is the rated torque of a Ø32 bellows coupling?**

4.5 Nm, 19000 rpm, M3 clamp screw, length 46, lateral misalignment 0.2 mm, axial ±0.7 mm.

**How much misalignment does a bellows coupling allow?**

In GN 2244: 0.15 to 0.2 mm lateral, ±0.5 to ±1 mm axial, 1.5° angular, depending on size.

**Bellows or jaw coupling?**

Bellows is torsionally stiff and backlash-free; a jaw coupling damps vibration but is softer. See the jaw coupling page for L-series sizes.

## Fits with

- [Flexible shaft couplers, 5–10 mm bores](https://xemstudio.com/objects/shaft-couplers/)
- [Jaw (spider) couplings L035 to L225: bore range, overall diameter, length, hub width, set screw](https://xemstudio.com/objects/jaw-spider-couplings-l-series/)
- [NEMA 23 stepper motor: 56.4 mm face, 47.14 mm hole pattern](https://xemstudio.com/objects/nema-23-stepper/)
- [T8 lead screw Tr8×8 envelope, 100 to 400 mm](https://xemstudio.com/objects/t8-lead-screw/)
- [Ball screw end supports BK10, BK12, BK15, BF10, BF12, BF15, FK, FF: bore, bearing, base hole spacing, height (HIWIN tables)](https://xemstudio.com/objects/ball-screw-end-supports-bk-bf-fk-ff/)
- [Linear shafts Ø3 to Ø25 mm (h6), 100 to 1000 mm long](https://xemstudio.com/objects/linear-shafts-h6/)