Straight Tee Dimensions
A straight tee takes a branch right off the run at 90°, with dat branch bein' the exact same size as the run. It's the standard way to split or mix up flow in welded pipe, and next to the elbow, it's the most-used fitting y'all gonna see on most jobs.
Run and branch.
The run is the through path; the branch is the outlet at right angles to it. On a straight tee all three ends share the same nominal size, so the R dimension (center to run end) and the B dimension (center to branch end) come straight from the table.
Full-size branchin' without a weldolet.
Where dat branch is the same size as the header, a tee is a much cleaner answer than a fabricated branch connection: you get a factory-made fitting to ASME B16.9 with a known rating, 'stead of some reinforcement calculation you gotta defend.
How To Read Dese Dimensions
ASME B16.9 dimensions the straight tee and rates it as a fittin', which is the practical reason for usin' one instead of a fabricated branch: there ain't no reinforcement calculation to defend. The R and B center-to-end dimensions down below are the standard figures, I reckon.
- O.D.
- Outside diameterOutside diameter at the weldin' end, matchin' up perfect with the pipe it welds to.
- I.D.
- Inside diameterBore right through the fitting, set by dat wall thickness.
- T
- Wall thicknessNominal wall at the weldin' end, matched to the pipe schedule.
- R
- Center to end, runFrom the intersection of the centerlines to the welding face on either end of the run.
- B
- Center to end, branchFrom the intersection of the centerlines to the welding face on the branch outlet.
121 sizes across 6 schedules · dimensions in inches, weights in pounds · ASME B16.9
Schedule STD
| Nom. Pipe Size | Outside Diameter O.D. | Inside Diameter I.D. | Wall Thickness T | Center to Center R | Center to End B | Pipe Schedule Number | Approx. Weight in Pounds Lbs. |
|---|---|---|---|---|---|---|---|
| ½ | 0.84 | 0.622 | 0.109 | 1.00 | 1.00 | 40 | 0.35 |
| ¾ | 1.05 | 0.824 | 0.113 | 1.12 | 1.12 | 40 | 0.50 |
| 1 | 1.32 | 1.049 | 0.133 | 1.50 | 1.50 | 40 | 0.75 |
| 1¼ | 1.66 | 1.380 | 0.140 | 1.88 | 1.88 | 40 | 1.30 |
| 1½ | 1.90 | 1.610 | 0.145 | 2.25 | 2.25 | 40 | 1.90 |
| 2 | 2.38 | 2.067 | 0.154 | 2.50 | 2.50 | 40 | 3.20 |
| 2½ | 2.88 | 2.469 | 0.203 | 3.00 | 3.00 | 40 | 5.80 |
| 3 | 3.50 | 3.068 | 0.216 | 3.38 | 3.38 | 40 | 7.20 |
| 3½ | 4.00 | 3.548 | 0.226 | 3.75 | 3.75 | 40 | 9.50 |
| 4 | 4.50 | 4.026 | 0.237 | 4.12 | 4.12 | 40 | 12.70 |
| 5 | 5.56 | 5.047 | 0.258 | 4.88 | 4.88 | 40 | 20.80 |
| 6 | 6.62 | 6.065 | 0.280 | 5.62 | 5.62 | 40 | 33.10 |
| 8 | 8.62 | 7.981 | 0.322 | 7.00 | 7.00 | 40 | 56.50 |
| 10 | 10.75 | 10.020 | 0.365 | 8.50 | 8.50 | 40 | 90.90 |
| 12 | 12.75 | 12.000 | 0.375 | 10.00 | 10.00 | * | 136.00 |
| 14 | 14.00 | 13.250 | 0.375 | 11.00 | 11.00 | 30 | 162.00 |
| 16 | 16.00 | 15.250 | 0.375 | 12.00 | 12.00 | 30 | 206.00 |
| 18 | 18.00 | 17.250 | 0.375 | 13.50 | 13.50 | * | 272.00 |
| 20 | 20.00 | 19.250 | 0.375 | 15.00 | 15.00 | 20 | 350.00 |
| 24 | 24.00 | 23.250 | 0.375 | 17.00 | 17.00 | 20 | 508.00 |
| 30 | 30.00 | 29.250 | 0.375 | 22.00 | 22.00 | * | 835.00 |
| 36 | 36.00 | 35.250 | 0.375 | 26.50 | 26.50 | * | 1294.00 |
| 42 | 42.00 | 41.250 | 0.375 | 30.00 | 28.00 | * | 1495.00 |
| 48 | 48.00 | 47.250 | 0.375 | 35.00 | 33.00 | * | 2300.00 |
Schedule XS
| Nom. Pipe Size | Outside Diameter O.D. | Inside Diameter I.D. | Wall Thickness T | Center to Center R | Center to End B | Pipe Schedule Number | Approx. Weight in Pounds Lbs. |
|---|---|---|---|---|---|---|---|
| ½ | 0.84 | 0.546 | 0.147 | 1.00 | 1.00 | 80 | 0.37 |
| ¾ | 1.05 | 0.742 | 0.154 | 1.12 | 1.12 | 80 | 0.58 |
| 1 | 1.32 | 0.957 | 0.179 | 1.50 | 1.50 | 80 | 0.87 |
| 1¼ | 1.66 | 1.278 | 0.191 | 1.88 | 1.88 | 80 | 1.60 |
| 1½ | 1.90 | 1.500 | 0.200 | 2.25 | 2.25 | 80 | 2.30 |
| 2 | 2.38 | 1.939 | 0.218 | 2.50 | 2.50 | 80 | 3.90 |
| 2½ | 2.88 | 2.323 | 0.276 | 3.00 | 3.00 | 80 | 6.50 |
| 3 | 3.50 | 2.900 | 0.300 | 3.38 | 3.38 | 80 | 9.00 |
| 3½ | 4.00 | 3.364 | 0.318 | 3.75 | 3.75 | 80 | 12.20 |
| 4 | 4.50 | 3.826 | 0.337 | 4.12 | 4.12 | 80 | 16.20 |
| 5 | 5.56 | 4.813 | 0.375 | 4.88 | 4.88 | 80 | 26.60 |
| 6 | 6.62 | 5.761 | 0.432 | 5.62 | 5.62 | 80 | 41.80 |
| 8 | 8.62 | 7.625 | 0.500 | 7.00 | 7.00 | 80 | 76.20 |
| 10 | 10.75 | 9.750 | 0.500 | 8.50 | 8.50 | 60 | 115.00 |
| 12 | 12.75 | 11.750 | 0.500 | 10.00 | 10.00 | * | 169.00 |
| 14 | 14.00 | 13.000 | 0.500 | 11.00 | 11.00 | * | 237.00 |
| 16 | 16.00 | 15.000 | 0.500 | 12.00 | 12.00 | 40 | 284.00 |
| 18 | 18.00 | 17.000 | 0.500 | 13.50 | 13.50 | * | 353.00 |
| 20 | 20.00 | 19.000 | 0.500 | 15.00 | 15.00 | 30 | 442.00 |
| 24 | 24.00 | 23.000 | 0.500 | 17.00 | 17.00 | * | 625.00 |
| 30 | 30.00 | 29.000 | 0.500 | 22.00 | 22.00 | 20 | 1065.00 |
| 36 | 36.00 | 35.000 | 0.500 | 26.50 | 26.50 | 20 | 1610.00 |
| 42 | 42.00 | 41.000 | 0.500 | 30.00 | 28.00 | * | 1788.00 |
| 48 | 48.00 | 47.000 | 0.500 | 35.00 | 33.00 | * | 2300.00 |
Schedule 40
| Nom. Pipe Size | Outside Diameter O.D. | Inside Diameter I.D. | Wall Thickness T | Center to Center R | Center to End B | Pipe Schedule Number | Approx. Weight in Pounds Lbs. |
|---|---|---|---|---|---|---|---|
| ½ | 0.84 | 0.622 | 0.109 | 1.00 | 1.00 | 40 | 0.35 |
| ¾ | 1.05 | 0.824 | 0.113 | 1.12 | 1.12 | 40 | 0.50 |
| 1 | 1.32 | 1.054 | 0.133 | 1.50 | 1.50 | 40 | 0.75 |
| 1¼ | 1.66 | 1.380 | 0.140 | 1.88 | 1.88 | 40 | 1.30 |
| 1½ | 1.90 | 1.610 | 0.145 | 2.25 | 2.25 | 40 | 1.90 |
| 2 | 2.38 | 2.072 | 0.154 | 2.50 | 2.50 | 40 | 3.20 |
| 2½ | 2.88 | 2.474 | 0.203 | 3.00 | 3.00 | 40 | 5.80 |
| 3 | 3.50 | 3.068 | 0.216 | 3.38 | 3.38 | 40 | 7.20 |
| 3½ | 4.00 | 3.548 | 0.226 | 3.75 | 3.75 | 40 | 8.50 |
| 4 | 4.50 | 4.026 | 0.237 | 4.12 | 4.12 | 40 | 9.50 |
| 5 | 5.56 | 5.044 | 0.258 | 4.88 | 4.88 | 40 | 12.70 |
| 6 | 6.62 | 6.060 | 0.280 | 5.62 | 5.62 | 40 | 20.80 |
| 8 | 8.62 | 7.976 | 0.322 | 7.00 | 7.00 | 40 | 33.10 |
| 10 | 10.75 | 10.020 | 0.365 | 8.50 | 8.50 | 40 | 56.50 |
| 12 | 12.75 | 11.938 | 0.406 | 10.00 | 10.00 | 40 | 90.90 |
| 14 | 14.00 | 13.124 | 0.438 | 11.00 | 11.00 | 40 | 165.00 |
| 16 | 16.00 | 15.000 | 0.500 | 12.00 | 12.00 | 40 | 210.00 |
| 18 | 18.00 | 16.876 | 0.562 | 13.50 | 13.50 | 40 | 275.00 |
| 20 | 20.00 | 18.812 | 0.594 | 15.00 | 15.00 | 40 | 355.00 |
| 24 | 24.00 | 22.624 | 0.688 | 17.00 | 17.00 | 40 | 510.00 |
Schedule 80
| Nom. Pipe Size | Outside Diameter O.D. | Inside Diameter I.D. | Wall Thickness T | Center to Center R | Center to End B | Pipe Schedule Number | Approx. Weight in Pounds Lbs. |
|---|---|---|---|---|---|---|---|
| ½ | 0.84 | 0.546 | 0.147 | 1.00 | 1.00 | 80 | 0.37 |
| ¾ | 1.05 | 0.742 | 0.154 | 1.12 | 1.12 | 80 | 0.58 |
| 1 | 1.32 | 0.962 | 0.179 | 1.50 | 1.50 | 80 | 0.87 |
| 1¼ | 1.66 | 1.278 | 0.191 | 1.88 | 1.88 | 80 | 1.60 |
| 1½ | 1.90 | 1.500 | 0.200 | 2.25 | 2.25 | 80 | 2.30 |
| 2 | 2.38 | 1.944 | 0.218 | 2.50 | 2.50 | 80 | 3.90 |
| 2½ | 2.88 | 2.328 | 0.276 | 3.00 | 3.00 | 80 | 6.50 |
| 3 | 3.50 | 2.900 | 0.300 | 3.38 | 3.38 | 80 | 9.00 |
| 3½ | 4.00 | 3.364 | 0.318 | 3.75 | 3.75 | 80 | 12.20 |
| 4 | 4.50 | 3.826 | 0.337 | 4.12 | 4.12 | 80 | 16.20 |
| 5 | 5.56 | 4.810 | 0.375 | 4.88 | 4.88 | 80 | 26.60 |
| 6 | 6.62 | 5.756 | 0.432 | 5.62 | 5.62 | 80 | 41.80 |
| 8 | 8.62 | 7.620 | 0.500 | 7.00 | 7.00 | 80 | 76.20 |
| 10 | 10.75 | 9.562 | 0.594 | 8.50 | 8.50 | 80 | 120.00 |
| 12 | 12.75 | 11.374 | 0.688 | 10.00 | 10.00 | 80 | 175.00 |
| 14 | 14.00 | 12.500 | 0.750 | 11.00 | 11.00 | 80 | 240.00 |
| 16 | 16.00 | 14.312 | 0.844 | 12.00 | 12.00 | 80 | 290.00 |
| 18 | 18.00 | 16.124 | 0.938 | 13.50 | 13.50 | 80 | 360.00 |
| 20 | 20.00 | 17.938 | 1.031 | 15.00 | 15.00 | 80 | 450.00 |
| 24 | 24.00 | 21.562 | 1.219 | 17.00 | 17.00 | 80 | 630.00 |
Schedule 160
| Nom. Pipe Size | Outside Diameter O.D. | Inside Diameter I.D. | Wall Thickness T | Center to Center R | Center to End B | Pipe Schedule Number | Approx. Weight in Pounds Lbs. |
|---|---|---|---|---|---|---|---|
| ½ | 0.84 | 0.464 | 0.188 | 1.00 | 1.00 | 160 | 0.46 |
| ¾ | 1.05 | 0.612 | 0.219 | 1.12 | 1.12 | 160 | 0.73 |
| 1 | 1.32 | 0.820 | 0.250 | 1.50 | 1.50 | 160 | 1.09 |
| 1¼ | 1.66 | 1.160 | 0.250 | 1.88 | 1.88 | 160 | 2.00 |
| 1½ | 1.90 | 1.338 | 0.281 | 2.25 | 2.25 | 160 | 2.88 |
| 2 | 2.38 | 1.692 | 0.344 | 2.50 | 2.50 | 160 | 4.88 |
| 2½ | 2.88 | 2.130 | 0.375 | 3.00 | 3.00 | 160 | 8.13 |
| 3 | 3.50 | 2.624 | 0.438 | 3.38 | 3.38 | 160 | 11.25 |
| 4 | 4.50 | 3.438 | 0.531 | 4.12 | 4.12 | 160 | 20.25 |
| 5 | 5.56 | 4.310 | 0.625 | 4.88 | 4.88 | 160 | 33.25 |
| 6 | 6.62 | 5.182 | 0.719 | 5.62 | 5.62 | 160 | 52.25 |
| 8 | 8.62 | 6.808 | 0.906 | 7.00 | 7.00 | 160 | 95.25 |
| 10 | 10.75 | 8.500 | 1.125 | 8.50 | 8.50 | 160 | 143.75 |
| 12 | 12.75 | 10.126 | 1.312 | 10.00 | 10.00 | 160 | 211.25 |
| 14 | 14.00 | 11.188 | 1.406 | 11.00 | 11.00 | 160 | 296.25 |
| 16 | 16.00 | 12.812 | 1.594 | 12.00 | 12.00 | 160 | 355.00 |
| 18 | 18.00 | 14.438 | 1.781 | 13.50 | 13.50 | 160 | 441.25 |
| 20 | 20.00 | 16.062 | 1.969 | 15.00 | 15.00 | 160 | 552.50 |
| 24 | 24.00 | 19.312 | 2.344 | 17.00 | 17.00 | 160 | 781.25 |
Schedule XXS
| Nom. Pipe Size | Outside Diameter O.D. | Inside Diameter I.D. | Wall Thickness T | Center to Center R | Center to End B | Pipe Schedule Number | Approx. Weight in Pounds Lbs. |
|---|---|---|---|---|---|---|---|
| ½ | 0.84 | 0.252 | 0.294 | 1.00 | 1.00 | * | 0.51 |
| ¾ | 1.05 | 0.434 | 0.308 | 1.12 | 1.12 | * | 0.80 |
| 1 | 1.32 | 0.604 | 0.358 | 1.50 | 1.50 | * | 1.20 |
| 1¼ | 1.66 | 0.896 | 0.382 | 1.88 | 1.88 | * | 2.20 |
| 1½ | 1.90 | 1.100 | 0.400 | 2.25 | 2.25 | * | 3.16 |
| 2 | 2.38 | 1.508 | 0.436 | 2.50 | 2.50 | * | 5.36 |
| 2½ | 2.88 | 1.776 | 0.552 | 3.00 | 3.00 | * | 8.94 |
| 3 | 3.50 | 2.300 | 0.600 | 3.38 | 3.38 | * | 12.38 |
| 4 | 4.50 | 3.152 | 0.674 | 4.12 | 4.12 | * | 22.28 |
| 5 | 5.56 | 4.060 | 0.750 | 4.88 | 4.88 | * | 36.58 |
| 6 | 6.62 | 4.892 | 0.864 | 5.62 | 5.62 | * | 57.48 |
| 8 | 8.62 | 6.870 | 0.875 | 7.00 | 7.00 | * | 104.78 |
| 10 | 10.75 | 8.750 | 1.000 | 8.50 | 8.50 | 140 | 158.13 |
| 12 | 12.75 | 10.750 | 1.000 | 10.00 | 10.00 | 120 | 232.38 |
Materials We Supply
Straight Tee to ASME B16.9 in the grades below. Tell us the service and we'll confirm the right one for y'all.
| Material | Specification | Typical Service |
|---|---|---|
| Carbon Steel | ASTM A234 WPB / WPC | General process, steam, oil and gas gathering and utility lines |
| Low-Temp Carbon Steel | ASTM A420 WPL6 | Cold service to −50°F; LNG and northern pipeline work |
| Chrome-Moly Alloy | ASTM A234 WP11 / WP22 / WP91 | Elevated temperature; refinery heaters, power plant steam |
| Stainless Steel | ASTM A403 WP304/304L, WP316/316L | Corrosive service, chemical, food and beverage, water treatment |
| Duplex & Super Duplex | ASTM A815 UNS S31803 / S32750 | Chloride and seawater service, offshore, desalination |
Questions Folks Ask Us
What's the difference 'tween a straight tee and a reducing tee?
Branch size. On a straight tee, all three ends are the exact same nominal size. On a reducin' tee, dat branch is smaller than the run, which is what y'all usually see when you're tappin' a small line off a big ol' header.
What do the R and B dimensions mean on a tee?
R is center-to-end along the run and B is center-to-end on the branch. Both of 'em are measured from the intersection of the centerlines to the weldin' face, both are marked on dat drawin' above, and both are listed by size and schedule in the tables.
Is a tee better than a weldolet for a full-size branch?
For a full-size branch, generally yes. A tee is a factory fitting made to ASME B16.9 with an established pressure rating, whereas a fabricated branch connection needs a reinforcement calculation. Branch fittings make a whole lot more sense when the branch is much smaller than the header, I reckon.
