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ASME B16.9 Tee Dimensions

Views: 7 Author: Monica Publish Time: 2025-12-08 Origin: Site

This article provides the ASME B16.9 for buttwelding tees, both straight tees and reducing tees. All dimensions below are taken directly from the current ASME B16.9 tables.

What Is ASME B16.9?

ASME B16.9 standard, "Factory-Made Wrought Buttwelding Fittings." Established by the American Society of Mechanical Engineers, this standard ensures interoperability, safety, and reliability in sectors such as oil and gas, chemical processing, power generation, and water treatment.

It applies to fittings in nominal pipe sizes (NPS) ranging from ½ inch to 48 inches (DN 15 to DN 1200) and covers dimensions, tolerances, pressure ratings, testing, and marking requirements.

Scope of ASME B16.9 Tees

Scope and Product Types

ASME B16.9 covers a wide range of buttwelding fittings, including:

Elbows: Long-radius (LR) and short-radius (SR) elbows for changing flow direction.

Tees: Straight and reducing tees for branching pipelines.

Reducers: Concentric and eccentric reducers for connecting pipes of different diameters.

Caps: Used to seal the end of a pipeline.

Stub Ends: Utilized with lap joint flanges for systems requiring disassembly.

These fittings are welded directly to piping, creating a leak-proof connection. The standard includes requirements for both seamless and welded fittings, with wall thicknesses matching common pipe schedules.

Scope of ASME B16.9 Tees

ASME B16.9 covers seamless and welded wrought buttwelding equal and reducing tees in NPS ½ through NPS 48.

All tees in B16.9 are long-pattern only; there is no short-radius tee in this standard.

The standard designates:

Equal Tee (Straight Tee): Run and branch have identical diameters

Reducing Tee: Outlet is smaller than the run

Crosses follow the same dimensions as tees.

ASME B16.9 Equal Tee Dimensions

ASME B16.9 Straight Tees Dimension

NPS	DN	Outside Diameter at Bevel (mm)	Center-to-End Run (M) / Outlet (C) (mm)	Center-to-End (inches, nominal)
½	15	21.3	25	1
¾	20	26.7	29	1.12
1	25	33.4	38	1.5
1¼	32	42.2	48	1.88
1½	40	48.3	57	2.25
2	50	60.3	76	3
2½	65	73.0	95	3.75
3	80	88.9	114	4.5
3½	90	101.6	133	5.25
4	100	114.3	152	6
5	125	141.3	190	7.5
6	150	168.3	229	9
8	200	219.1	305	12
10	250	273.0	381	15
12	300	323.8	457	18
14	350	355.6	533	21
16	400	406.4	610	24
18	450	457.2	686	27
20	500	508.0	762	30
22	550	559	838	33
24	600	610	914	36
26	650	660	991	39
28	700	711	1067	42
30	750	762	1143	45
32	800	813	1219	48
34	850	864	1295	51
36	900	914	1372	54
38	950	965	1448	57
40	1000	1016	1524	60
42	1050	1067	1600	63
44	1100	1118	1676	66
46	1150	1168	1753	69
48	1200	1219	1829	72

Note: Dimensions are in millimeters. For sizes larger than NPS 24", dimensions and tolerances are specified in the standard and typically manufactured as welded fittings.

ASME B16.9 Tee Dimension Tolerance

Dimension	Tolerance
Center-to-End (C, M) – NPS ½–8	± 2 mm
Center-to-End (C, M) – NPS 10–18	± 3 mm
Center-to-End (C, M) – NPS 20–24	± 4 mm
Center-to-End (C, M) – NPS 26–30	± 5 mm
Center-to-End (C, M) – NPS 32–42	± 6 mm
Center-to-End (C, M) – NPS 44–48	± 7 mm
Overall length of reducing tees	Same tolerances as above apply to both M and C
Inside diameter at bevel	+1.6 mm / −0.8 mm
Wall thickness at bevel	Not less than 87.5 % of nominal pipe wall

ASME B16.9 Reducing Outlet Tees Size

Nominal Pipe Size (NPS)	DN	Outside Diameter at Bevel		Center-to-End
Nominal Pipe Size (NPS)	DN	Run	Outlet	Run, C	Outlet, M [Note (1)]
1/2 x 1/2 x 3/8	15 × 15 × 10	21.3	17.3	25	25
1/2 x1/2 x 1/4	15 × 15 × 8	21.3	13.7	25	25
3/4 x 3/4 x1/2	20 × 20 × 15	26.7	21.3	29	29
3/4 x 3/4 x 3/8	20 × 20 × 10	26.7	17.3	29	29
1 × 1 x 3/4	25 × 25 × 20	33.4	26.7	38	38
1 × 1 x 1/2	25 × 25 × 15	33.4	21.3	38	38
1 1/4 x 1 1/4 × 1	32 × 32 × 25	42.2	33.4	48	48
1 1/4 × 1 1/4 × 3/4	32 × 32 × 20	42.2	26.7	48	48
1 1/4 x 1 1/4 x 1/2	32 × 32 × 15	42.2	21.3	48	48
1 1/2 x 1 1/2 x 1/4	40 × 40 × 32	48.3	42.2	57	57
1 1/2 x 1 1/2 × 1	40 × 40 × 25	48.3	33.4	57	57
1 1/2 x 1 1/2 x 3/4	40 × 40 × 20	48.3	26.7	57	57
1 1/2 x 1 1/2x 1/2	40 × 40 × 15	48.3	21.3	57	57
2 × 2 × 1 1/2	50 × 50 × 40	60.3	48.3	64	60
2 × 2 × 1 1/4	50 × 50 × 32	60.3	42.2	64	57
2 × 2 × 1	50 × 50 × 25	60.3	33.4	64	51
2 × 2 × 3/4	50 × 50 × 20	60.3	26.7	64	44
2 1/2 x 2 1/2 × 2	65 × 65 × 50	73	60.3	76	70
2 1/2 x 2 1/2 x 1 1/2	65 × 65 × 40	73	48.3	76	67
2 1/2 × 2 1/2 × 1 1/4	65 × 65 × 32	73	42.2	76	64
2 1/2 × 2 1/2 × 1	65 × 65 × 25	73	33.4	76	57
3 × 3 × 2 1/2	80 × 80 × 65	88.9	73	86	83
3 × 3 × 2	80 × 80 × 50	88.9	60.3	86	76
3 × 3 × 1 1/2	80 × 80 × 40	88.9	48.3	86	73
3 × 3 × 1 1/4	80 × 80 × 32	88.9	42.2	86	70
3 1/2 x 3 1/2 × 3	90 × 90 × 80	101.6	88.9	95	92
3 1/2 × 3 1/2 × 2 1/2	90 × 90 × 65	101.6	73	95	89
3 1/2 × 3 1/2 × 2	90 × 90 × 50	101.6	60.3	95	83
3 1/2 × 3 1/2 × 1 1/2	90 × 90 × 40	101.6	48.3	95	79
4 × 4 × 3 1/2	100 × 100 × 90	114.3	101.6	105	102
4 × 4 × 3	100 × 100 × 80	114.3	88.9	105	98
4 × 4 × 2 1/2	100 × 100 × 65	113.3	73	105	95
4 × 4 × 2	100 × 100 × 50	114.3	60.3	105	89
4 × 4 × 1 1/2	100 × 100 × 40	114.3	48.3	105	86
5 × 5 × 4	125 × 125 × 100	141.3	114.3	125	117
5 × 5 × 3 1/2	125 × 125 × 90	141.3	101.6	124	114
5 × 5 × 3	125 × 125 × 80	141.3	88.9	124	111
5 × 5 × 2 1/2	125 × 125 × 65	141.3	73	124	108
5 × 5 × 2	125 × 125 × 50	141.3	60.3	124	105
6 × 6 × 5	150 × 150 × 125	168.3	141.3	143	137
6 × 6 × 4	150 × 150 × 100	168.3	114.3	143	130
6 × 6 × 3 1/2	150 × 150 × 90	168.3	101.6	143	127
6 × 6 × 3	150 × 150 × 80	168.3	88.9	143	124
6 × 6 × 2 1/2	150 × 150 × 65	168.3	73	143	121
8 × 8 × 6	200 × 200 × 150	219.1	168.3	178	168
8 × 8 × 5	200 × 200 × 125	219.1	141.3	178	162
8 × 8 × 4	200 × 200 × 100	219.1	114.3	178	156
8 × 8 × 3 1/2	200 × 200 × 90	219.1	101.6	178	152
10 × 10 × 8	250 × 250 × 200	273	219.1	216	203
10 × 10 × 6	250 × 250 × 150	273	168.3	216	194
10 × 10 × 5	250 × 250 × 125	273	141.3	216	191
10 × 10 × 4	250 × 250 × 100	273	114.3	216	184
12 × 12 × 10	300 × 300 × 250	323.8	273	254	241
12 × 12 × 8	300 × 300 × 200	323.8	219.1	254	229
12 × 12 × 6	300 × 300 × 150	323.8	168.3	254	219
12 × 12 × 5	300 × 300 × 125	323.8	141.3	254	216
14 × 14 × 12	350 × 350 × 300	355.6	323.8	279	270
14 × 14 × 10	350 × 350 × 250	355.6	273	279	257
14 × 14 × 8	350 × 350 × 200	355.6	219.1	279	248
14 × 14 × 6	350 × 350 × 150	355.6	168.3	279	238
16 × 16 × 14	400 × 400 × 350	406.4	355.6	305	305
16 × 16 × 12	400 × 400 × 300	406.4	323.8	305	295
16 × 16 × 10	400 × 400 × 250	406.4	273	305	283
16 × 16 × 8	400 × 400 × 200	406.4	219.1	305	273
16 × 16 × 6	400 × 400 × 150	406.4	168.3	305	264
18 × 18 × 16	450 × 450 × 400	457	406.4	343	330
18 × 18 × 14	450 × 450 × 350	457	355.6	343	330
18 × 18 × 12	450 × 450 × 300	457	323.8	343	321
18 × 18 × 10	450 × 450 × 250	457	273	343	308
18 × 18 × 8	450 × 450 × 200	457	219.1	343	298
20 × 20 × 18	500 × 500 × 450	508	457	381	368
20 × 20 × 16	500 × 500 × 400	508	406.4	381	356
20 × 20 × 14	500 × 500 × 350	508	355.6	381	356
20 × 20 × 12	500 × 500 × 300	508	323.8	381	346
20 × 20 × 10	500 × 500 × 250	508	273	381	333
20 × 20 × 8	500 × 500 × 200	508	219.1	381	324
22 × 22 × 20	550 × 550 × 500	559	508	419	406
22 × 22 × 18	550 × 550 × 450	559	457	419	394
22 × 22 × 16	550 × 550 × 400	559	406.4	419	381
22 × 22 × 14	550 × 550 × 350	559	355.6	419	381
22 × 22 × 12	550 × 550 × 300	559	323.8	419	371
22 × 22 × 10	550 × 550 × 250	559	273	419	359
24 × 24 × 22	600 × 600 × 550	610	559	432	432
24 × 24 × 20	600 × 600 × 500	610	508	432	432
24 × 24 × 18	600 × 600 × 450	610	457	432	419
24 × 24 × 16	600 × 600 × 400	610	406.4	432	406
24 × 24 × 14	600 × 600 × 350	610	355.6	432	406
24 × 24 × 12	600 × 600 × 300	610	323.8	432	397
24 × 24 × 10	600 × 600 × 250	610	273	432	384
26 × 26 × 24	650 × 650 × 600	660	610	495	483
26 × 26 × 22	650 × 650 × 550	660	559	495	470
26 × 26 × 20	650 × 650 × 550	660	508	495	457
26 × 26 × 18	650 × 650 × 450	660	457	495	444
26 × 26 × 16	650 × 650 × 400	660	406.4	495	432
26 × 26 × 14	650 × 650 × 350	660	355.6	495	432
26 × 26 × 12	650 × 650 × 300	660	323.8	495	422
28 × 28 × 26	700 × 700 × 650	711	660	521	521
28 × 28 × 24	700 × 700 × 600	711	610	521	508
28 × 28 × 22	700 × 700 × 550	711	559	521	495
28 × 28 × 20	700 × 700 × 500	711	508	521	483
28 × 28 × 18	700 × 700 × 450	711	457	521	470
28 × 28 × 16	700 × 700 × 400	711	406.4	521	457
28 × 28 × 14	700 × 700 × 350	711	355.6	521	457
28 × 28 × 12	700 × 700 × 300	711	323.8	521	448
30 × 30 × 28	750 × 750 × 700	762	711	559	546
30 × 30 × 26	750 × 750 × 650	762	660	559	546
30 × 30 × 24	750 × 750 × 600	762	610	559	533
30 × 30 × 22	750 × 750 × 550	762	559	559	521
30 × 30 × 20	750 × 750 × 500	762	508	559	508
30 × 30 × 18	750 × 750 × 450	762	457	559	495
30 × 30 × 16	750 × 750 × 400	762	406.4	559	483
30 × 30 × 14	750 × 750 × 350	762	355.6	559	483
30 × 30 × 12	750 × 750 × 300	762	323.8	559	473
30 × 30 × 10	750 × 750 × 250	762	273	559	460
32 × 32 × 30	800 × 800 × 750	813	762	597	584
32 × 32 × 28	800 × 800 × 700	813	711	597	572
32 × 32 × 26	800 × 800 × 650	813	660	597	572
32 × 32 × 24	800 × 800 × 600	813	610	597	559
32 × 32 × 22	800 × 800 × 550	813	559	597	546
32 × 32 × 20	800 × 800 × 500	813	508	597	533
32 × 32 × 18	800 × 800 × 450	813	457	597	521
32 × 32 × 16	800 × 800 × 400	813	406.4	597	508
32 × 32 × 14	800 × 800 × 350	813	355.6	597	508
34 × 34 × 32	850 × 850 × 800	864	813	635	622
34 × 34 × 30	850 × 850 × 750	864	762	635	610
34 × 34 × 28	850 × 850 × 700	864	711	635	597
34 × 34 × 26	850 × 850 × 650	864	600	635	597
34 × 34 × 24	850 × 850 × 600	864	610	635	584
34 × 34 × 22	850 × 850 × 550	864	559	635	572
34 × 34 × 20	850 × 850 × 500	864	508	635	559
34 × 34 × 18	850 × 850 × 450	864	457	635	546
34 × 34 × 16	850 × 850 × 400	864	406.4	635	533
36 × 36 × 34	900 × 900 × 850	914	864	673	660
36 × 36 × 32	900× 900 × 800	914	813	673	648
36 × 36 × 30	900× 900 × 750	914	762	673	635
36 × 36 × 28	900× 900 × 700	914	711	673	622
36 × 36 × 26	900× 900 × 650	914	660	673	622
36 × 36 × 24	900× 900 × 600	914	610	673	610
36 × 36 × 22	900× 900 × 550	914	559	673	597
36 × 36 × 20	900× 900 × 500	914	508	673	584
36 × 36 × 18	900× 900 × 450	914	457	673	572
36 × 36 × 16	900× 900 × 400	914	406.4	673	559
38 × 38 × 36	950 × 950 × 900	965	914	711	711
38 × 38 × 34	950 × 950 × 850	965	864	711	698
38 × 38 × 32	950 × 950 × 800	965	813	711	686
38 × 38 × 30	950 × 950 × 750	965	762	711	673
38 × 38 × 28	950 × 950 × 700	965	711	711	648
38 × 38 × 26	950 × 950 × 650	965	660	711	648
38 × 38 × 24	950 × 950 × 600	965	610	711	635
38 × 38 × 22	950 × 950 × 550	965	559	711	622
38 × 38 × 20	950 × 950 × 500	965	508	711	610
38 × 38 × 18	950 × 950 × 450	965	457	711	597
40 × 40 × 38	1000 × 1000 × 950	1016	965	749	749
40 × 40 × 36	1000 × 1000 × 900	1016	914	749	737
40 × 40 × 34	1000 × 1000 × 850	1016	864	749	724
40 × 40 × 32	1000 × 1000 × 800	1016	813	749	711
40 × 40 × 30	1000 × 1000 × 750	1016	762	749	698
40 × 40 × 28	1000 × 1000 × 700	1016	711	749	673
40 × 40 × 26	1000 × 1000 × 650	1016	560	749	673
40 × 40 × 24	1000 × 1000 × 600	1016	610	749	660
40 × 40 × 22	1000 × 1000 × 550	1016	559	749	648
40 × 40 × 20	1000 × 1000 × 500	1016	508	749	635
40 × 40 × 18	1000 × 1000 × 450	1016	457	749	622
42 × 42 × 40	1050 × 1050 × 1000	1067	1016	762	711
42 × 42 × 38	1050 × 1050 × 950	1067	968	762	711
42 × 42 × 36	1050 × 1050 × 900	1067	914	762	711
42 × 42 × 34	1050 × 1050 × 850	1067	864	762	711
42 × 42 × 32	1050 × 1050 × 800	1067	813	762	711
42 × 42 × 30	1050 × 1050 × 750	1067	762	762	711
42 × 42 × 28	1050 × 1050 × 700	1067	711	762	698
42 × 42 × 26	1050 × 1050 × 650	1067	660	762	698
42 × 42 × 24	1050 × 1050 × 600	1067	610	762	660
42 × 42 × 22	1050 × 1050 × 550	1067	559	762	660
42 × 42 × 20	1050 × 1050 × 500	1067	508	762	660
42 × 42 × 18	1050 × 1050 × 450	1067	457	762	648
42 × 42 × 16	1050 × 1050 × 400	1067	406.4	762	635
44 × 44 × 42	1100 × 1100 × 1050	1118	1067	813	762
44 × 44 × 40	1100 × 1100 × 1000	1118	1016	813	749

GENERAL NOTE: All dimensions are in millimeters.

NOTE:

(1) Outlet dimension M for run sizes NPS 14 (DN 350) and larger is recommended but not required.

ASME B16.9 Tee Materials and Specifications

ASME B16.9 tees are manufactured from a wide range of materials to suit various pressure, temperature, and corrosion requirements. The material must be specified to match the connected piping.

Common material specifications include:

Carbon Steel: ASTM A234 WPB

Stainless Steel: ASTM A403 WP304/304L, 316/316L, 321, 347

Alloy Steel: ASTM A234 WP5, WP9, WP11, WP22, WP91

Low-Temperature Carbon Steel: ASTM A420 WPL3, WpL6

Duplex & Super Duplex Steel: ASTM A815 UNS S31803, S32205

Conclusion

When selecting a tee, it is crucial to specify the correct Nominal Pipe Size, the type (equal or reducing), and the required schedule to match the piping specifications.

Contact us for the latest Tee prices!

ASME B16.9 Tee Dimensions

What Is ASME B16.9?

Scope of ASME B16.9 Tees

ASME B16.9 Equal Tee Dimensions

ASME B16.9 Tee Dimension Tolerance

ASME B16.9 Reducing Outlet Tees Size

ASME B16.9 Tee Materials and Specifications

Conclusion

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