{
 "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-thermal-break-spacer",
 "name": "Tri-clamp thermal-break spacer, 2 in × 25.4 mm: an insulating section with its own two clamp faces",
 "kind": "hardware",
 "category": "Hardware",
 "group": "Sanitary clamp fittings",
 "year": null,
 "question": "How do I put a thermal break between two tri-clamp sections?",
 "tags": [
  "thermal break",
  "spacer",
  "insulating",
  "tri-clamp",
  "spool",
  "stirling",
  "long earth society"
 ],
 "aliases": [
  "tri clamp thermal break",
  "insulating tri clamp spacer",
  "tri clamp heat break",
  "thermal isolator sanitary"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": true,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/tri-clamp-thermal-break-spacer/",
 "sheet_txt": "https://xemstudio.com/objects/tri-clamp-thermal-break-spacer/sheet.txt",
 "sheet": {
  "basis": "Design values; faces from the shared ISO 2852 ferrule profile (gen_hardware.tc_spool); conduction estimates are mine (assumptions stated)",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "Two clamp faces on one short insulating body: clamp it between a warm section and a part that must stay cool (an alternator, a seal, magnets). Each face has its own gasket and clamp, so the heat path through it is only its own wall.",
   "Why not a ring in one joint: every tri-clamp joint already has a gasket between the faces, and the metal path across a joint is the clamp itself, which grips both rims on their 20° cones. A thin insulating ring in a joint adds little; the clamp still bridges it. With the spacer, the two clamps never touch each other.",
   "Where it goes: only where the temperature suits what it is made of. On my modular thermoacoustic engine it can only sit at the cold joint (above the ambient exchanger, at the cooling water's temperature); the hot joint runs at about 550 °C, which an insulating ring rated to about 260 °C cannot take.",
   "What it costs there: its bore adds 27.1 mm of cold gas between the stack and the piston, which lowers the pressure swing per stroke: 4.3 W against 10.2 W at the design point (model). So it is optional on that engine.",
   "Pressure: at a 15 bar gauge relief the hoop stress in a 1.65 wall would be 23 MPa; the builder checks that against what it is made of, at its temperature, and may leave it at 1 bar."
  ],
  "table": {
   "columns": [
    "part",
    "face_to_face_mm",
    "bore_mm",
    "outside between faces_mm",
    "joints",
    "clamps"
   ],
   "rows": [
    [
     "break-spacer-2in-25.4",
     25.4,
     47.5,
     50.8,
     2,
     2
    ]
   ]
  }
 },
 "sheet_text": "Tri-clamp thermal-break spacer, 2 in × 25.4 mm: an insulating section with its own two clamp faces — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/tri-clamp-thermal-break-spacer/  (CC BY 4.0)\nBasis: Design values; faces from the shared ISO 2852 ferrule profile (gen_hardware.tc_spool); conduction estimates are mine (assumptions stated)\nCatalog version: 2026-10-20\n\nSizes: see table below\n- Two clamp faces on one short insulating body: clamp it between a warm section and a part that must stay cool (an alternator, a seal, magnets). Each face has its own gasket and clamp, so the heat path through it is only its own wall.\n- Why not a ring in one joint: every tri-clamp joint already has a gasket between the faces, and the metal path across a joint is the clamp itself, which grips both rims on their 20° cones. A thin insulating ring in a joint adds little; the clamp still bridges it. With the spacer, the two clamps never touch each other.\n- Where it goes: only where the temperature suits what it is made of. On my modular thermoacoustic engine it can only sit at the cold joint (above the ambient exchanger, at the cooling water's temperature); the hot joint runs at about 550 °C, which an insulating ring rated to about 260 °C cannot take.\n- What it costs there: its bore adds 27.1 mm of cold gas between the stack and the piston, which lowers the pressure swing per stroke: 4.3 W against 10.2 W at the design point (model). So it is optional on that engine.\n- Pressure: at a 15 bar gauge relief the hoop stress in a 1.65 wall would be 23 MPa; the builder checks that against what it is made of, at its temperature, and may leave it at 1 bar.\n\npart  face_to_face_mm  bore_mm  outside between faces_mm  joints  clamps\nbreak-spacer-2in-25.4  25.4  47.5  50.8  2  2\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 (tube OD and wall, clamp fittings) — standard — ASME; dimensions are facts [verify license at link] — https://www.asme.org/codes-standards/find-codes-standards/bpe-bioprocessing-equipment\n- Xem Studio: tools/gen_ta_modular.py: the section geometry, the network model and every number on these pages — code — CC BY 4.0 — https://xemstudio.com/\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, 1 parts): https://xemstudio.com/files/hardware/tri-clamp-thermal-break-spacer/index.json\nAPI: https://xemstudio.com/api/geometry?object=tri-clamp-thermal-break-spacer\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 (tube OD and wall, clamp fittings)",
   "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": "Xem Studio",
   "title": "tools/gen_ta_modular.py: the section geometry, the network model and every number on these pages",
   "url": "https://xemstudio.com/",
   "formats": [
    "code"
   ],
   "license": "CC BY 4.0",
   "license_verified": true,
   "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": [
  "list-ta-modular-free-piston-2in",
  "tri-clamp-spool",
  "tri-clamp-gasket",
  "tri-clamp-clamps",
  "sanitary-high-pressure-clamp"
 ],
 "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": "faces",
   "exact": "ISO 2852 2 in, both ends (land Ø56.5–Ø64, rim 2.85, 1.6 recess, 20° back)",
   "mates": "Type B gasket + clamp at each face (two clamps, not touching)",
   "fit": "clamp",
   "files": "all"
  },
  {
   "feature": "bore",
   "exact": "Ø47.5",
   "mates": "gas passage (no contact)",
   "fit": "designed",
   "files": "all"
  },
  {
   "feature": "outside between the faces",
   "exact": "Ø50.8",
   "mates": "clamp room (no contact)",
   "fit": "designed",
   "files": "all"
  }
 ],
 "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": "Can it be the hot joint's ring?",
   "a": "Not on the modular engine: the hot joint runs at about 550 °C; the break goes where its rating allows, the cold joint."
  },
  {
   "q": "Does it seal like a spool?",
   "a": "Yes: the faces are the standard ISO 2852 profile, with a Type B gasket and a clamp at each."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "break-spacer-2in-25.4",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/tri-clamp-thermal-break-spacer/break-spacer-2in-25.4.step",
   "stl": "https://xemstudio.com/files/hardware/tri-clamp-thermal-break-spacer/break-spacer-2in-25.4.stl",
   "note": "2 in × 25.4 mm thermal-break spacer: ISO 2852 faces both ends (the standard ferrule profile), Ø47.5 bore, Ø50.8 between the faces; two clamps, one on each face, so no clamp bridges it"
  }
 ],
 "markdown": "https://xemstudio.com/objects/tri-clamp-thermal-break-spacer/index.md"
}