# Filler plugs for a 2 in tee: run plug with the displacer-rod bore and branch plug, with a Ø12 gas passage

> How do I use a standard 2 in tee in a Stirling engine without its dead volume?

- Category: Hardware › Stirling & thermoacoustic
- Kind: Hardware
- Basis: Stock 2 in tee bore Ø47.5 (ASME BPE); passage size from the cycle model
- Page: https://xemstudio.com/objects/tri-clamp-tee-filler-plugs/ · JSON: https://xemstudio.com/api/geometry?object=tri-clamp-tee-filler-plugs · Plain text: https://xemstudio.com/objects/tri-clamp-tee-filler-plugs/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 standard 2 in tee holds about 390 mL of gas. Two inserts fill it: a run plug (slid in from a run end) and a branch plug whose saddle-shaped bottom sits on it. What is left is a Ø12 passage from the hot spool's side up to the power cylinder, the displacer rod's Ø6.6 bore and a Ø4 hole to the gland cap's ports.
- Gas left in the tee and its joints about 25.9 mL; Ø44 spigots reach through each gasket's lip to 0.5 mm from what they face.

## 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 |
|---|---|---|---|---|
| outside | Ø47.50 | 2 in tee bore | slide | all |
| spigots | Ø44.0 | inside the gasket lips (no contact) | designed | all |
| rod bore | Ø6.6 | Ø6 displacer rod (no contact) | designed | tee-run-plug* |
| saddle | Ø47.50 cylinder | run plug (rests on it) | designed | tee-branch-plug* |

## Sizes

| part | size |
|---|---|
| tee-run-plug-2in-rod6 | Ø47.50 × 172.9, spigots Ø44 |
| tee-branch-plug-2in | Ø47.50 to 86.45, spigot Ø44 |

## Where the files are

- 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
- 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)
- Long Earth Society: [Engine builds](https://longearthsociety.com/engineering/) — web, video — LES site

## Free STEP/STL (2 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/tri-clamp-tee-filler-plugs/index.json

- tee-run-plug-2in-rod6: [STEP](https://xemstudio.com/files/hardware/tri-clamp-tee-filler-plugs/tee-run-plug-2in-rod6.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-tee-filler-plugs/tee-run-plug-2in-rod6.stl) — run filler Ø47.50 × 172.9 for a 2 in tee with Ø44 spigots to x ±92.05 / 91.70, Ø6.6 rod bore, Ø12 passages (z 12 axial, x 0 up), Ø4 to the +X end
- tee-branch-plug-2in: [STEP](https://xemstudio.com/files/hardware/tri-clamp-tee-filler-plugs/tee-branch-plug-2in.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-tee-filler-plugs/tee-branch-plug-2in.stl) — branch filler Ø47.50 from the run bore to 86.45, Ø44 spigot to 92.05, Ø12 passage on the axis

## Questions

**Do they seal?**

No, they only fill: the gasket and clamps seal. The fit in the bore is a slide fit.

## Fits with

- [Build list: Tri-clamp walking-beam gamma generator, 2 in, chargeable](https://xemstudio.com/objects/list-tri-clamp-walking-beam-gamma/)
- [Sanitary clamp tees and short-outlet tees (7MP, 7MPS): ½ to 4 in](https://xemstudio.com/objects/sanitary-clamp-tees/)