3 in end caps with a bored 608 bearing boss: shaft-seal version and blind version with three 1/4 NPT bosses — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/tri-clamp-bearing-cap-3in/  (CC BY 4.0)
Basis: ISO 2852 3 in face (Ø91 flange, Ø83.5 groove); 608 and ISO 6194-1 8 × 22 × 7 sizes from their standards; 1/4 NPT per ASME B1.20.1
Catalog version: 2026-10-20

Sizes: see table below
- Two 3 in end caps close the run of a 3 in tee (the crankcase) and carry the crankshaft in a 608 each. On the output side an 8 × 22 × 7 rotary shaft seal sits outboard of the bearing against the outer shoulder: the crankcase pressure pushes it onto the shoulder.
- The blind cap carries the crankcase's three 1/4 NPT ports: fill valve, gauge and relief valve.
- A plain lip seal is made for a small pressure difference; for a charged crankcase use a type its maker rates above the relief setting.

part  bore  ports
bearing-cap-3in-608-seal  Ø22 to 35: 608 + seal, Ø12 shoulder  —
bearing-cap-3in-608-3x-npt14  Ø22 to 28: 608  3 × 1/4 NPT on r 27

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- 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
- 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
- ASME: ASME B1.20.1 Pipe Threads, General Purpose, Inch (NPT): 1/4-18 major Ø13.72, tap drill 7/16 in (11.1), L2 10.2 — standard — ASME; dimensions are facts [verify license at link] — https://www.asme.org/codes-standards/find-codes-standards/b1-20-1-pipe-threads-general-purpose-inch
- ISO: ISO 6194-1 Rotary shaft lip-type seals: nominal dimensions (8 × 22 × 7 is a listed size) — standard — dimensions are facts [verify license at link] — https://www.iso.org/standard/41300.html
- Long Earth Society: Engine builds — web, video — LES site — https://longearthsociety.com/engineering/

Free files (CC BY 4.0, Xem Studio; STEP + STL, 2 parts): https://xemstudio.com/files/hardware/tri-clamp-bearing-cap-3in/index.json
API: https://xemstudio.com/api/geometry?object=tri-clamp-bearing-cap-3in