2 in × 6 in spool with three 1/4 NPT bosses at mid-length — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/tri-clamp-spool-npt-bosses/  (CC BY 4.0)
Basis: Stock 2 in × 6 in spool; 1/4 NPT per ASME B1.20.1; boss size and positions are design values
Catalog version: 2026-10-20

Sizes: see table below
- A standard 2 in × 6 in spool with three welded 1/4 NPT bosses round its middle: fill valve, pressure gauge and relief valve on one charged space.
- On the horizontal gamma it is the bounce space behind the power piston: about 0.37 L that holds the mean charge so the piston only works against the cycle's swing.

feature  value
length  152.4 face to face
bosses  3 × 1/4 NPT at mid-length, 90° / 30° / 150°
boss  Ø22 to r 36, tap drill Ø11.1 × 12, Ø6 on

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

Free files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/tri-clamp-spool-npt-bosses/index.json
API: https://xemstudio.com/api/geometry?object=tri-clamp-spool-npt-bosses