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Tri-clamp rolling-diaphragm power head, 2 in: standard clamp face, cylinder, rod guide and crank tower, with its diaphragm seat ring

Name: Tri-clamp rolling-diaphragm power head, 2 in: standard clamp face, cylinder, rod guide and crank tower, with its diaphragm seat ring dimension sheet
Creator: Xem Studio
License: https://creativecommons.org/licenses/by/4.0/

How do I mount a rolling diaphragm power piston on a tri-clamp fitting? · Hardware · basis: ISO 2852 face, rim, recess and 20° back cone as the flat end cap on this site; rolling-diaphragm bore, radii and stroke from the published 1.50 in size; 625 and 5 × 8 × 12 bushing sizes from their standards; crank geometry is a design value

Long Earth Society build part. The heart of my rolling-diaphragm engines: I clamp it on and the piston problem is gone. 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: 9 in table

Notes

One part behind a standard 2 in clamp joint. Its clamped end is a standard ISO 2852 2 in face: the land, the 2.85 mm rim, the 1.6 mm recess inside Ø56.5 and the 20° back cone, exactly as an end cap's, so the standard clamp closes on it and it goes on any 2 in ferrule.
The diaphragm's flange (0.51) takes the place of the gasket. Between the flange and the head sits the seat ring: 1.19 mm on the land and down into the head's recess inside Ø56.5, so flange plus ring are the 1.7 mm of a Type B gasket's web and the clamp closes exactly as it does on a gasket. The ring carries the 1/16 in mouth radius the diaphragm wall rolls off, and its Ø38.10 bore runs on into the head's.
Behind the ring: the Ø38.10 bore the diaphragm rolls in, down to a floor 49 mm from the clamp plane with four Ø6 vents so the back of the diaphragm is at air pressure; a Ø16 boss with an Ø8 seat for two 5 × 8 × 12 sleeve bushings that guide the Ø5 tube piston rod.
A tower on −Y carries two 625 bearings (Ø16 × 5 pockets, 24 apart) on a Ø5 crankshaft 188 mm from the clamp plane: a 20 mm stroke crank disc on the shaft end, a conrod-80 down to the rod yoke. The flywheel goes on the far end.
The same head goes on the 2 in cup of the beta (straight up) and on the branch of a standard 2 in tee in the Ringbom and gamma (sideways).

Sizes

feature	value_mm
clamp face	ISO 2852 2 in, face plane 0.85 from the clamp plane
seat ring on the land	1.19
seat ring in the recess	2.79
bore Ø	38.1
bore depth	49.0
bushing seat	Ø8 × 24
bearing pockets	Ø16 × 5, y −26 and −50
shaft axis	188.0
stroke	20.0

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
clamp face	ISO 2852 2 in (land Ø56.5–Ø64.0, rim 2.85, 1.6 recess, 20° back), face plane 0.85 from the clamp plane	2 in clamp; seat ring and diaphragm flange in place of a gasket	clamp	rd-power-head*
face recess	Ø56.5 × 1.6	seat ring (fills it)	slide	rd-power-head*
cylinder bore	Ø38.10 from the recess floor to 49	rolling diaphragm outer wall (piston 2.41 clear)	designed	rd-power-head*
seat ring OD in the recess	Ø56.5 × 1.6	power head face recess	slide	rd-seat-ring*
seat ring on the land	Ø56.5–Ø63.5 × 1.19	power head land and the diaphragm flange (flange + ring = 1.7, a Type B web)	clamp	rd-seat-ring*
seat ring bore	Ø38.10, 1/16 in mouth radius	rolling diaphragm wall (rolls off the radius)	designed	rd-seat-ring*
bushing seat	Ø8 × 24	two 5 × 8 × 12 sleeve bushings	press	all
bearing pockets	Ø16 × 5 (two)	625 bearing	press	all
shaft passage	Ø8	Ø5 crankshaft (no contact)	designed	all
floor vents	4 × Ø6	air (back of the diaphragm)	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	PDF	standard excerpt; dimensions are facts
ASME	BPE Bioprocessing Equipment (clamp fitting dimensions, tube OD and wall)	standard	ASME; dimensions are facts verify
Marsh Bellofram	Rolling diaphragm design manual (2022): nomenclature, height formula, standard-size tables, hardware radii	PDF	publisher's manual; dimensions cited, nothing copied
Long Earth Society	Engine builds	web, video	LES site

Free files

★ Free files 2 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json

rd-power-head-2in	2 in rolling-diaphragm power head: standard ISO 2852 2 in clamp face (land Ø56.5–Ø64, rim 2.85, recess 1.6 inside Ø56.5, 20° back cone; face plane 0.85 from the clamp plane), Ø38.10 bore from the recess floor to 49, floor 6 with 4 × Ø6 vents, Ø16 boss with an Ø8 × 24 seat for two 5 × 8 × 12 bushings, crank tower with two Ø16 × 5 bearing pockets on the shaft axis 188 above the clamp plane	STEP · STL
rd-seat-ring-2in	diaphragm seat ring: Ø63.5 × 1.19 on the land (Ø56.5–Ø63.5), 2.79 thick inside Ø56.5 (fills the head's 1.6 recess), bore Ø38.10 with the 1/16 in mouth radius	STEP · STL

Plain text: sheet.txt · JSON: /api/geometry?object=tri-clamp-rd-power-head