# Tri-clamp flexure carrier: clamp-in 2 in, two Ø40 flexure stacks

> Where do the flexure bearings of a sealed free piston go in a tri-clamp engine?

- Category: Stirling engines › Tri-clamp engine parts
- Kind: Hardware
- Basis: ISO 2852 faces as the ferrule on this site; ledge hole circle = the Ø40 spiral flexure's rim holes (r 17.6)
- Page: https://xemstudio.com/objects/tri-clamp-flexure-carrier/ · JSON: https://xemstudio.com/api/geometry?object=tri-clamp-flexure-carrier · Plain text: https://xemstudio.com/objects/tri-clamp-flexure-carrier/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.** Every file is drawn at true size with no printing tolerance. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your printer's or process's clearance before making the part.

## Notes

- A part with a full 2 in ferrule face on each side, clamped between the honed cylinder and the next fitting like a thick gasket (each side its own gasket and clamp). Inside, two ledges carry two flexure stacks of Ø40 spiral leaves 48 mm apart, so the piston's rod is held on centre at two points and the mover never touches the bore.
- Stack A hangs under the upper ledge, stack B stands on the lower ledge; each is leaf, spacer, leaf (opposite hand), clamp plate, with three M3 × 10 into the ledge. The rod passes the Ø31 ledge windows; M4 nuts and washers clamp the leaf hubs.
- The carrier's inside is part of the gas space behind the piston.
- Fits: faces are clamp faces; the M3 holes are tap drills; the ledge windows are clearance (designed).

## Mating features (exact size; open press / slide / run / socket by your process clearance, leave designed and clamp as drawn)

| feature | exact | mates with | fit | files |
|---|---|---|---|---|
| faces | ISO 2852 both sides (land Ø56.5–Ø64, rim 2.85, 1.6 recess, 20° back to Ø50.8) | standard clamps + Type B gaskets | clamp | all |
| ledge holes | 2 × 3 × Ø2.5 (M3 tap drill) on r 17.6 | shcs-m3x10 through the flexure stacks | designed | all |
| ledge windows | Ø31 × 4 | leaf arms, hubs and hub nuts at ±8 stroke (no contact) | designed | all |
| ledge faces | flat ring Ø31–Ø47.5 | flexure leaf rims | designed | all |
| neck | Ø50.8 | spool hanger (ring engine) | clamp | all |

## Sizes

| feature | value |
|---|---|
| face to face | 60 |
| ledges | Ø31 window, 4 thick |
| holes | 3 × M3 on r 17.6 |

## Where the files are

- ASME: [BPE Bioprocessing Equipment (clamp fitting dimensions, tube OD and wall)](https://www.asme.org/codes-standards/find-codes-standards/bpe-bioprocessing-equipment) — standard — ASME; dimensions are facts (verify at link)
- ISO (via iTeh sample): [ISO 2852 clamp liners: face profile and flange / groove diameters](https://cdn.standards.iteh.ai/samples/7850/eb49c396488d408c8ced3e2961d76cf3/ISO-2852-1974.pdf) — PDF — standard excerpt; dimensions are facts
- Long Earth Society: [Engine builds](https://longearthsociety.com/engineering/) — web, video — LES site

## Free STEP/STL (1 parts, CC BY 4.0, Xem Studio)

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

- flexure-carrier-2in-60: [STEP](https://xemstudio.com/files/hardware/tri-clamp-flexure-carrier/flexure-carrier-2in-60.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-flexure-carrier/flexure-carrier-2in-60.stl) — flexure carrier 60 face to face: ISO 2852 2 in face each side on a Ø50.8 neck, Ø47.5 bore, ledges Ø47.5 / Ø31 × 4 at 6–10 and 50–54 from the top face, 3 × M3 tap drill Ø2.5 on r 17.6 each

## Questions

**Why clamp-in?**

The stacks must sit inside the pressure boundary on the same axis as the cylinder; a part with a ferrule face both sides does that and keeps every joint a standard clamp joint.

## Fits with

- [Planar spiral flexure bearing leaves: Ø40 to Ø120, 3-arm and 2-arm, 0.5 and 2 mm](https://xemstudio.com/objects/spiral-flexure-bearing/)
- [Free-piston mover for a 2 in honed spool: piston and alternator magnets in one, Ø48.00 × 130](https://xemstudio.com/objects/free-piston-mover-2in/)
- [Clamp-in bearing plate: 2 in, two ISO 2852 faces, spigot with two 623 seats](https://xemstudio.com/objects/tri-clamp-clamp-in-bearing-plate/)
- [Build list: Thermoacoustic-Stirling ring generator, three 2 in units, pressurised](https://xemstudio.com/objects/list-ta-ring-3x2in/)