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2 in × 6 in spool with three 1/4 NPT bosses at mid-length
How do I put gauge, fill and relief ports on a tri-clamp spool? · Hardware · basis: Stock 2 in × 6 in spool; 1/4 NPT per ASME B1.20.1; boss size and positions are design values
Long Earth Society build part. The bounce space of my horizontal gamma. The engines
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. Mating features
- sizes
- 3 in table
Notes
- 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.
Sizes
| 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 |
Mating features
Drawn at the exact size. Open press, slide, run and socket features by your process's clearance; leave designed gaps and clamp fits as drawn.
| feature | exact | mates with | fit | files |
|---|---|---|---|---|
| faces | ISO 2852 2 in, 152.4 face to face | Type B gaskets, 2 in clamps | clamp | all |
| NPT bosses | 3 × 1/4-18 NPT, tap drill Ø11.1 × 12, Ø6 through | fill valve, gauge, relief valve (1/4 NPT male) | designed | all |
Where the files are
Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.
| ISO (via iTeh sample) | ISO 2852 clamp liners: face profile and flange / groove diameters | standard excerpt; dimensions are facts | |
| ASME | BPE Bioprocessing Equipment (clamp fitting dimensions, tube OD and wall) | standard | ASME; dimensions are facts verify |
| 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 |
| Long Earth Society | Engine builds | web, video | LES site |
Free files
★ Free files 1 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json
| spool-2in-6in-3x-npt14 | 2 in × 6 in (152.4) spool, ISO 2852 faces, stock bore, three 1/4 NPT bosses at mid-length (90°, 30°, 150° from +X; Ø22 out to r 36, tap drill Ø11.1 × 12, Ø6 through the wall) | STEP · STL |
Plain text: sheet.txt · JSON: /api/geometry?object=tri-clamp-spool-npt-bosses

How it fits
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Questions
Which port is which?
Top: fill valve. The two at 30° and 150°: gauge and relief.

