{
 "version": "2026-10-20",
 "license": "Dimension sheets are written by Xem Studio from the cited sources and are free to use (CC BY 4.0, attribute 'Xem Studio'). Linked files belong to their publishers under the license shown; Xem Studio does not host them. 'license_verified: false' means the license shown is from memory or the publisher's page as last read and should be confirmed at the link before commercial use.",
 "slug": "tri-clamp-rd-tee-inserts",
 "name": "Tee inserts, 2 in: volume fillers for the run and branch of a standard 2 in equal tee",
 "kind": "hardware",
 "category": "Hardware",
 "group": "Stirling & thermoacoustic",
 "year": null,
 "question": "How do I cut the dead volume of a standard tri-clamp tee in a Stirling engine?",
 "tags": [
  "insert",
  "filler",
  "dead volume",
  "tee",
  "tri-clamp",
  "stirling",
  "long earth society"
 ],
 "aliases": [
  "tri clamp tee filler",
  "stirling dead volume tee",
  "tee insert 2 inch"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": true,
 "free_files": 3,
 "url": "https://xemstudio.com/objects/tri-clamp-rd-tee-inserts/",
 "sheet_txt": "https://xemstudio.com/objects/tri-clamp-rd-tee-inserts/sheet.txt",
 "sheet": {
  "basis": "ASME BPE 2 in bore Ø47.5, Type B lip 1.95 past each face, standard 2 in equal tee (7MP) run 177.8 and branch 88.9 centre to face; passages and spigot are design values",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "A standard 2 in equal tee has 177.8 mm of run and 88.9 mm of branch: about 400 mL of gas that would do no work in a Stirling engine. Two inserts fill it. The run insert is a Ø47.5 cylinder 173.9 mm long that sits between the two Type B gasket lips; the branch insert slides into the branch and its saddle end sits on the run insert.",
   "The gas goes up an Ø7 riser in the run insert to the branch axis, then out along the branch insert's Ø8 passage to the rolling diaphragm. The branch insert's Ø10 spigot sits in a counterbore at the end of the run insert's passage, so the passages line up and the run insert cannot turn.",
   "The displacer rod runs up the axis of the run insert in its own rod way: Ø9 for the Ringbom's Ø8 rod, Ø4 for the gamma's Ø3 rod. The Ringbom insert has a short Ø18 cavity at the bottom for the displacer cap's boss at the top of its travel.",
   "On top the run insert has a Ø45.3 spigot that passes through the upper gasket's lip and stops 0.5 mm under the gland cap's recess floor, so the top joint holds almost no gas; the cap's M5 port reaches the working gas through that gap and the rod way.",
   "The branch insert ends 0.5 mm short of the branch face, under the diaphragm's flange."
  ],
  "table": {
   "columns": [
    "part",
    "od_mm",
    "length_mm",
    "rod_way_mm"
   ],
   "rows": [
    [
     "rd-tee-insert-2in-ringbom",
     47.5,
     173.9,
     9
    ],
    [
     "rd-tee-insert-2in-gamma",
     47.5,
     173.9,
     4
    ],
    [
     "rd-branch-insert-2in",
     47.5,
     "saddle to 88.4",
     ""
    ]
   ]
  }
 },
 "sheet_text": "Tee inserts, 2 in: volume fillers for the run and branch of a standard 2 in equal tee — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/tri-clamp-rd-tee-inserts/  (CC BY 4.0)\nBasis: ASME BPE 2 in bore Ø47.5, Type B lip 1.95 past each face, standard 2 in equal tee (7MP) run 177.8 and branch 88.9 centre to face; passages and spigot are design values\nCatalog version: 2026-10-20\n\nSizes: see table below\n- A standard 2 in equal tee has 177.8 mm of run and 88.9 mm of branch: about 400 mL of gas that would do no work in a Stirling engine. Two inserts fill it. The run insert is a Ø47.5 cylinder 173.9 mm long that sits between the two Type B gasket lips; the branch insert slides into the branch and its saddle end sits on the run insert.\n- The gas goes up an Ø7 riser in the run insert to the branch axis, then out along the branch insert's Ø8 passage to the rolling diaphragm. The branch insert's Ø10 spigot sits in a counterbore at the end of the run insert's passage, so the passages line up and the run insert cannot turn.\n- The displacer rod runs up the axis of the run insert in its own rod way: Ø9 for the Ringbom's Ø8 rod, Ø4 for the gamma's Ø3 rod. The Ringbom insert has a short Ø18 cavity at the bottom for the displacer cap's boss at the top of its travel.\n- On top the run insert has a Ø45.3 spigot that passes through the upper gasket's lip and stops 0.5 mm under the gland cap's recess floor, so the top joint holds almost no gas; the cap's M5 port reaches the working gas through that gap and the rod way.\n- The branch insert ends 0.5 mm short of the branch face, under the diaphragm's flange.\n\npart  od_mm  length_mm  rod_way_mm\nrd-tee-insert-2in-ringbom  47.5  173.9  9.0\nrd-tee-insert-2in-gamma  47.5  173.9  4\nrd-branch-insert-2in  47.5  saddle to 88.4  \n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- ISO (via iTeh sample): ISO 2852 clamp liners: face profile and flange / groove diameters — PDF — standard excerpt; dimensions are facts — https://cdn.standards.iteh.ai/samples/7850/eb49c396488d408c8ced3e2961d76cf3/ISO-2852-1974.pdf\n- ASME: BPE Bioprocessing Equipment (clamp fitting dimensions, tube OD and wall) — standard — ASME; dimensions are facts [verify license at link] — https://www.asme.org/codes-standards/find-codes-standards/bpe-bioprocessing-equipment\n- Long Earth Society: Engine builds — web, video — LES site — https://longearthsociety.com/engineering/\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 3 parts): https://xemstudio.com/files/hardware/tri-clamp-rd-tee-inserts/index.json\nAPI: https://xemstudio.com/api/geometry?object=tri-clamp-rd-tee-inserts\n",
 "sources": [
  {
   "publisher": "ISO (via iTeh sample)",
   "title": "ISO 2852 clamp liners: face profile and flange / groove diameters",
   "url": "https://cdn.standards.iteh.ai/samples/7850/eb49c396488d408c8ced3e2961d76cf3/ISO-2852-1974.pdf",
   "formats": [
    "PDF"
   ],
   "license": "standard excerpt; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "ASME",
   "title": "BPE Bioprocessing Equipment (clamp fitting dimensions, tube OD and wall)",
   "url": "https://www.asme.org/codes-standards/find-codes-standards/bpe-bioprocessing-equipment",
   "formats": [
    "standard"
   ],
   "license": "ASME; dimensions are facts",
   "license_verified": false,
   "hosted": false
  },
  {
   "publisher": "Long Earth Society",
   "title": "Engine builds",
   "url": "https://longearthsociety.com/engineering/",
   "formats": [
    "web",
    "video"
   ],
   "license": "LES site",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "sanitary-clamp-tees",
  "tri-clamp-rd-gland-caps",
  "tri-clamp-volume-filler",
  "list-tri-clamp-rd-ringbom",
  "list-tri-clamp-rd-gamma"
 ],
 "fits": [],
 "dimensions": "exact (nominal, no printing tolerance)",
 "dimension_rule": "All geometry on Xem Studio is exact (nominal, true size) with no printing tolerance. Where a part meets another part, the object lists its mating features (feature, exact size, what it mates with, fit class: press, slide, run, socket, clamp or designed). Apply your process's allowance to those features only; 'designed' gaps are part of the design and stay as drawn.",
 "mating": [
  {
   "feature": "run insert OD",
   "exact": "Ø47.5",
   "mates": "bore of the 2 in tee's run",
   "fit": "slide",
   "files": "rd-tee-insert-"
  },
  {
   "feature": "run insert length",
   "exact": "173.9 between the Type B lips",
   "mates": "lower lip (it stands on it)",
   "fit": "designed",
   "files": "rd-tee-insert-"
  },
  {
   "feature": "top spigot",
   "exact": "Ø45.3",
   "mates": "upper Type B gasket lip; 0.5 under the gland cap's recess floor",
   "fit": "slide",
   "files": "rd-tee-insert-"
  },
  {
   "feature": "spigot counterbore",
   "exact": "Ø10 × 4",
   "mates": "branch insert spigot",
   "fit": "slide",
   "files": "rd-tee-insert-"
  },
  {
   "feature": "rod way",
   "exact": "Ø9 (Ringbom) / Ø4 (gamma)",
   "mates": "Ø8 / Ø3 rod (no contact)",
   "fit": "designed",
   "files": "rd-tee-insert-"
  },
  {
   "feature": "branch insert OD",
   "exact": "Ø47.5",
   "mates": "bore of the tee's branch",
   "fit": "slide",
   "files": "rd-branch-insert-"
  },
  {
   "feature": "saddle",
   "exact": "R23.75 about the run axis",
   "mates": "run insert OD",
   "fit": "slide",
   "files": "rd-branch-insert-"
  },
  {
   "feature": "spigot",
   "exact": "Ø10 × 4",
   "mates": "run insert counterbore",
   "fit": "slide",
   "files": "rd-branch-insert-"
  },
  {
   "feature": "end to the branch face plane",
   "exact": "0.5",
   "mates": "diaphragm flange (no contact)",
   "fit": "designed",
   "files": "rd-branch-insert-"
  }
 ],
 "fit_classes": {
  "press": "stays put: pin, tube, bearing or magnet held by interference. Typical FDM: hole +0.0 to +0.1 mm on diameter.",
  "slide": "assembles by hand and is held by a grub, pinch or clamp: shaft in a hub, rod in a socket, spigot in a bore. Typical FDM: +0.2 mm.",
  "run": "turns or slides in use: pin in a link, rod through a guide. Typical FDM: +0.3 mm.",
  "socket": "large sliding fit: syringe barrel, sleeve, bobbin in a bore. Typical FDM: +0.3 mm.",
  "clamp": "split part that closes on the mating part with screws: make it at size.",
  "designed": "a gap that is part of the design (piston fit option, displacer gap, air gap): do not change."
 },
 "faq": [
  {
   "q": "Why not a custom compact tee?",
   "a": "A standard tee is the cheapest fitting there is and takes a stock clamp and gasket on every end; the inserts take its volume away."
  },
  {
   "q": "How are they held?",
   "a": "The run insert stands on the lower gasket lip and its top spigot passes the upper one; the branch insert is held between the run insert and the diaphragm's flange, 0.5 mm clear of it."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "rd-tee-insert-2in-ringbom",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/tri-clamp-rd-tee-inserts/rd-tee-insert-2in-ringbom.step",
   "stl": "https://xemstudio.com/files/hardware/tri-clamp-rd-tee-inserts/rd-tee-insert-2in-ringbom.stl",
   "note": "run insert Ø47.5 × 173.90 (between the two Type B lips of a 2 in equal tee): Ø18 × 6.85 axis cavity, Ø7 riser at x 17 to the branch axis (86.95 up) and out along +X, Ø10 × 4 counterbore for the branch insert's spigot, Ø45.3 spigot on top through the upper gasket's lip to 0.5 under the gland cap's recess floor, Ø9 rod way on the axis"
  },
  {
   "file": "rd-tee-insert-2in-gamma",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/tri-clamp-rd-tee-inserts/rd-tee-insert-2in-gamma.step",
   "stl": "https://xemstudio.com/files/hardware/tri-clamp-rd-tee-inserts/rd-tee-insert-2in-gamma.stl",
   "note": "run insert Ø47.5 × 173.90: as the Ringbom insert with no axis cavity and an Ø4 rod way"
  },
  {
   "file": "rd-branch-insert-2in",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/tri-clamp-rd-tee-inserts/rd-branch-insert-2in.step",
   "stl": "https://xemstudio.com/files/hardware/tri-clamp-rd-tee-inserts/rd-branch-insert-2in.stl",
   "note": "branch insert Ø47.5: saddle on the run bore to 88.4 from the run axis (0.5 short of the branch face plane), Ø10 × 4 spigot into the run insert, Ø8 passage on its axis"
  }
 ],
 "markdown": "https://xemstudio.com/objects/tri-clamp-rd-tee-inserts/index.md"
}