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Butt-weld reducers, concentric and eccentric (ASME B16.9), NPS ¾ to 12

Name: Butt-weld reducers, concentric and eccentric (ASME B16.9), NPS ¾ to 12 dimension sheet
Creator: Xem Studio
License: https://creativecommons.org/licenses/by/4.0/

What is the end-to-end length of a butt-weld concentric or eccentric reducer (ASME B16.9)? · Standard part · basis: ASME B16.9 dimensions as published in SHIELD's manufacturer table (mm); OD and Sch 40 wall per ASME B36.10 (Weldbend)

Also called: butt weld reducer dimensions, concentric reducer length, eccentric reducer dimensions, b16.9 reducer, weld reducer step, pipe reducer stl

Exact dimensions. True size, with no printing tolerance added.

sizes: 55 in table

Notes

Concentric and eccentric reducers share the same end-to-end length H for each size pair. An eccentric reducer keeps one side straight (flat side down in a pump suction, up for drainage).
Files: 2 × 1 and 4 × 2, concentric and eccentric, Schedule 40 at each end. The shape of the transition is the manufacturer's: the files run a straight cone over the full length between the two ends.
OD and Schedule 40 wall: Weldbend prints OD rounded (1.32, 2.38 in); the files use the exact ASME B36.10 OD (1.315, 2.375, 4.500 in) with the Weldbend Sch 40 wall (.133, .154, .237 in). Fittings are made to match the pipe's OD and wall.
Ends are drawn square. Real fittings are bevelled for welding to ASME B16.25; no public, citable statement of the bevel was found, so it is not drawn.

Butt-weld reducers, concentric and eccentric (ASME B16.9), NPS ¾ to 12 size chart

size, NPS	large-end OD, mm	small-end OD, mm	end-to-end H, mm
3/4 × 3/8	26.7	17.3	38
3/4 × 1/2	26.7	21.3	38
1 × 1/2	33.4	21.3	51
1 × 3/4	33.4	26.7	51
1-1/4 × 1/2	42.2	21.3	51
1-1/4 × 3/4	42.2	26.7	51
1-1/4 × 1	42.2	33.4	51
1-1/2 × 1/2	48.3	21.3	64
1-1/2 × 3/4	48.3	26.7	64
1-1/2 × 1	48.3	33.4	64
1-1/2 × 1-1/4	48.3	42.2	64
2 × 3/4	60.3	26.7	76
2 × 1	60.3	33.4	76
2 × 1-1/4	60.3	42.2	76
2 × 1-1/2	60.3	48.3	76
2-1/2 × 1	73.0	33.4	89
2-1/2 × 1-1/4	73.0	42.2	89
2-1/2 × 1-1/2	73.0	48.3	89
2-1/2 × 2	73.0	60.3	89
3 × 1-1/4	88.9	42.2	89
3 × 1-1/2	88.9	48.3	89
3 × 2	88.9	60.3	89
3 × 2-1/2	88.9	73.0	89
3-1/2 × 1-1/4	101.6	42.2	102
3-1/2 × 1-1/2	101.6	48.3	102
3-1/2 × 2	101.6	60.3	102
3-1/2 × 2-1/2	101.6	73.0	102
3-1/2 × 3	101.6	88.9	102
4 × 1-1/2	114.3	48.3	102
4 × 2	114.3	60.3	102
4 × 2-1/2	114.3	73.0	102
4 × 3	114.3	88.9	102
4 × 3-1/2	114.3	101.6	102
5 × 2	141.3	60.3	127
5 × 2-1/2	141.3	73.0	127
5 × 3	141.3	88.9	127
5 × 3-1/2	141.3	101.6	127
5 × 4	141.3	114.3	127
6 × 2-1/2	168.3	73.0	140
6 × 3	168.3	88.9	140
6 × 3-1/2	168.3	101.6	140
6 × 4	168.3	114.3	140
6 × 5	168.3	141.3	140
8 × 3-1/2	219.1	101.6	152
8 × 4	219.1	114.3	152
8 × 5	219.1	141.3	152
8 × 6	219.1	168.3	152
10 × 4	273.0	114.3	178
10 × 5	273.0	141.3	178
10 × 6	273.0	168.3	178
10 × 8	273.0	219.1	178
12 × 5	323.8	141.3	203
12 × 6	323.8	168.3	203
12 × 8	323.8	219.1	203
12 × 10	323.8	273.0	203

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

SHIELD (manufacturer)	Butt-welded fittings & flanges, SG-BWFF: ASME B16.9 elbows, tees, reducers (mm)	web	Publisher's page; dimensions are facts
Weldbend Corporation	Weld fitting & weld flange catalog, 63rd edition: 90° and 45° long-radius elbows, OD, STD / Sch 40 wall	web	Publisher's page; dimensions are facts

Free files

★ Free files 4 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json

bw-reducer-concentric-nps2x1-sch40	NPS 2 × 1 concentric reducer, Sch 40 each end, end-to-end 76 mm; drawn as a straight cone between the ends (transition shape not set by B16.9); square ends	STEP · STL
bw-reducer-eccentric-nps2x1-sch40	NPS 2 × 1 eccentric reducer, Sch 40 each end, end-to-end 76 mm; drawn as a straight cone between the ends (transition shape not set by B16.9); square ends	STEP · STL
bw-reducer-concentric-nps4x2-sch40	NPS 4 × 2 concentric reducer, Sch 40 each end, end-to-end 102 mm; drawn as a straight cone between the ends (transition shape not set by B16.9); square ends	STEP · STL
bw-reducer-eccentric-nps4x2-sch40	NPS 4 × 2 eccentric reducer, Sch 40 each end, end-to-end 102 mm; drawn as a straight cone between the ends (transition shape not set by B16.9); square ends	STEP · STL

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Plain text: sheet.txt · JSON: /api/geometry?object=butt-weld-reducers