180° Short Radius Return Bend Dimensions
The short radius return bend reverses flow on a 1.0D centerline radius, foldin' the line back in the tightest space the standard allows. It's what y'all use when coil spacin' just won't accommodate dat long radius pattern.
Tighter spacin', tighter tolerances.
Dat short radius pattern brings the two legs closer together, which is exactly what heater and exchanger coil pitch often demands. The trade-off is the same as with elbows: more turbulence through the turn, and more concentrated wear on the outside of the bend.
Match the pattern to the coil.
Coil pitch is fixed by the bundle or the firebox, so dat return bend pattern is usually dictated rather than chosen. Confirm the V dimension against the design pitch before orderin'. Long and short patterns ain't interchangeable.
How To Read Dese Dimensions
The short radius return is an ASME B16.28 fittin' rather than an ASME B16.9 one: B16.28 is the standard coverin' short radius buttweldin' elbows and returns. It runs NPS 1/2 through NPS 24, and dat tight center-to-center V below is the whole reason the pattern even exists.
- 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.
- V
- Center to centerRight between the centerlines of them two legs, and dat's the whole reason the short pattern even exists.
- W
- Back to faceFrom the outside of the bend to the welding face.
101 sizes across 6 schedules · dimensions in inches, weights in pounds · ASME B16.28
Schedule STD
| Nom. Pipe Size | Outside Diameter O.D. | Inside Diameter I.D. | Wall Thickness T | Center to Center V | Back to Face W | Pipe Schedule Number | Approx. Weight in Pounds Lbs. |
|---|---|---|---|---|---|---|---|
| 1 | 1.32 | 1.049 | 0.133 | 2.00 | 1.62 | 40 | 0.50 |
| 1¼ | 1.66 | 1.380 | 0.140 | 2.50 | 2.06 | 40 | 0.80 |
| 1½ | 1.90 | 1.610 | 0.145 | 3.00 | 2.44 | 40 | 1.10 |
| 2 | 2.38 | 2.067 | 0.154 | 4.00 | 3.19 | 40 | 1.90 |
| 2½ | 2.88 | 2.469 | 0.203 | 5.00 | 3.94 | 40 | 4.00 |
| 3 | 3.50 | 3.068 | 0.216 | 6.00 | 4.75 | 40 | 6.00 |
| 3½ | 4.00 | 3.548 | 0.226 | 7.00 | 5.50 | 40 | 8.70 |
| 4 | 4.50 | 4.026 | 0.237 | 8.00 | 6.25 | 40 | 12.20 |
| 5 | 5.56 | 5.047 | 0.258 | 10.00 | 7.75 | 40 | 19.20 |
| 6 | 6.62 | 6.065 | 0.280 | 12.00 | 9.31 | 40 | 32.90 |
| 8 | 8.62 | 7.981 | 0.322 | 16.00 | 12.31 | 40 | 64.90 |
| 10 | 10.75 | 10.020 | 0.365 | 20.00 | 15.38 | 40 | 112.00 |
| 12 | 12.75 | 12.000 | 0.375 | 24.00 | 18.38 | * | 157.00 |
| 14 | 14.00 | 13.250 | 0.375 | 28.00 | 21.00 | 30 | 208.00 |
| 16 | 16.00 | 15.250 | 0.375 | 32.00 | 24.00 | 30 | 257.00 |
| 18 | 18.00 | 17.250 | 0.375 | 36.00 | 27.00 | * | 325.00 |
| 20 | 20.00 | 19.250 | 0.375 | 40.00 | 30.00 | 20 | 416.00 |
| 24 | 24.00 | 23.250 | 0.375 | 48.00 | 36.00 | 20 | 592.00 |
Schedule XS
| Nom. Pipe Size | Outside Diameter O.D. | Inside Diameter I.D. | Wall Thickness T | Center to Center V | Back to Face W | Pipe Schedule Number | Approx. Weight in Pounds Lbs. |
|---|---|---|---|---|---|---|---|
| 1 | 1.32 | 0.962 | 0.179 | 2.00 | 1.62 | 80 | 0.70 |
| 1¼ | 1.66 | 1.278 | 0.191 | 2.50 | 2.06 | 80 | 1.00 |
| 1½ | 1.90 | 1.500 | 0.200 | 3.00 | 2.44 | 80 | 1.50 |
| 2 | 2.38 | 1.939 | 0.218 | 4.00 | 3.19 | 80 | 2.90 |
| 2½ | 2.88 | 2.323 | 0.276 | 5.00 | 3.94 | 80 | 5.20 |
| 3 | 3.50 | 2.900 | 0.300 | 6.00 | 4.75 | 80 | 8.20 |
| 3½ | 4.00 | 3.364 | 0.318 | 7.00 | 5.50 | 80 | 11.70 |
| 4 | 4.50 | 3.826 | 0.337 | 8.00 | 6.25 | 80 | 16.40 |
| 5 | 5.56 | 4.813 | 0.375 | 10.00 | 7.75 | 80 | 27.70 |
| 6 | 6.62 | 5.761 | 0.432 | 12.00 | 9.31 | 80 | 45.70 |
| 8 | 8.62 | 7.625 | 0.500 | 16.00 | 12.31 | 80 | 96.30 |
| 10 | 10.75 | 9.750 | 0.500 | 20.00 | 15.38 | 60 | 143.00 |
| 12 | 12.75 | 11.750 | 0.500 | 24.00 | 18.38 | * | 212.00 |
| 14 | 14.00 | 13.000 | 0.500 | 28.00 | 21.00 | * | 271.00 |
| 16 | 16.00 | 15.000 | 0.500 | 32.00 | 24.00 | 40 | 339.00 |
| 18 | 18.00 | 17.000 | 0.500 | 36.00 | 27.00 | * | 425.00 |
| 20 | 20.00 | 19.000 | 0.500 | 40.00 | 30.00 | 30 | 555.00 |
| 24 | 24.00 | 23.000 | 0.500 | 48.00 | 36.00 | * | 778.00 |
Schedule 40
| Nom. Pipe Size | Outside Diameter O.D. | Inside Diameter I.D. | Wall Thickness T | Center to Center V | Back to Face W | Pipe Schedule Number | Approx. Weight in Pounds Lbs. |
|---|---|---|---|---|---|---|---|
| 1 | 1.32 | 1.054 | 0.133 | 2.00 | 1.62 | 40 | 0.50 |
| 1¼ | 1.66 | 1.380 | 0.140 | 2.50 | 2.06 | 40 | 0.80 |
| 1½ | 1.90 | 1.610 | 0.145 | 3.00 | 2.44 | 40 | 1.10 |
| 2 | 2.38 | 2.072 | 0.154 | 4.00 | 3.19 | 40 | 1.90 |
| 2½ | 2.88 | 2.474 | 0.203 | 5.00 | 3.94 | 40 | 4.00 |
| 3 | 3.50 | 3.068 | 0.216 | 6.00 | 4.75 | 40 | 6.00 |
| 3½ | 4.00 | 3.548 | 0.226 | 7.00 | 5.50 | 40 | 8.70 |
| 4 | 4.50 | 4.026 | 0.237 | 8.00 | 6.25 | 40 | 12.20 |
| 5 | 5.56 | 5.044 | 0.258 | 10.00 | 7.75 | 40 | 19.20 |
| 6 | 6.62 | 6.060 | 0.280 | 12.00 | 9.31 | 40 | 32.90 |
| 8 | 8.62 | 7.976 | 0.322 | 16.00 | 12.31 | 40 | 64.90 |
| 10 | 10.75 | 10.020 | 0.365 | 20.00 | 15.38 | 40 | 112.00 |
| 12 | 12.75 | 11.938 | 0.406 | 24.00 | 18.38 | 40 | 165.00 |
| 14 | 14.00 | 13.124 | 0.438 | 28.00 | 21.00 | 40 | 215.00 |
| 16 | 16.00 | 15.000 | 0.500 | 32.00 | 24.00 | 40 | 265.00 |
| 18 | 18.00 | 16.876 | 0.562 | 36.00 | 27.00 | 40 | 335.00 |
| 20 | 20.00 | 18.812 | 0.594 | 40.00 | 30.00 | 40 | 425.00 |
| 24 | 24.00 | 22.624 | 0.688 | 48.00 | 36.00 | 40 | 605.00 |
Schedule 80
| Nom. Pipe Size | Outside Diameter O.D. | Inside Diameter I.D. | Wall Thickness T | Center to Center V | Back to Face W | Pipe Schedule Number | Approx. Weight in Pounds Lbs. |
|---|---|---|---|---|---|---|---|
| 1 | 1.32 | 0.962 | 0.179 | 2.00 | 1.62 | 80 | 0.70 |
| 1¼ | 1.66 | 1.278 | 0.191 | 2.50 | 2.06 | 80 | 1.00 |
| 1½ | 1.90 | 1.500 | 0.200 | 3.00 | 2.44 | 80 | 1.50 |
| 2 | 2.38 | 1.944 | 0.218 | 4.00 | 3.19 | 80 | 2.90 |
| 2½ | 2.88 | 2.328 | 0.276 | 5.00 | 3.94 | 80 | 5.20 |
| 3 | 3.50 | 2.900 | 0.300 | 6.00 | 4.75 | 80 | 8.20 |
| 3½ | 4.00 | 3.364 | 0.318 | 7.00 | 5.50 | 80 | 11.70 |
| 4 | 4.50 | 3.826 | 0.337 | 8.00 | 6.25 | 80 | 16.40 |
| 5 | 5.56 | 4.810 | 0.375 | 10.00 | 7.75 | 80 | 27.70 |
| 6 | 6.62 | 5.756 | 0.432 | 12.00 | 9.31 | 80 | 45.70 |
| 8 | 8.62 | 7.620 | 0.500 | 16.00 | 12.31 | 80 | 96.30 |
| 10 | 10.75 | 9.562 | 0.594 | 20.00 | 15.38 | 80 | 160.00 |
| 12 | 12.75 | 11.374 | 0.688 | 24.00 | 18.38 | 80 | 225.00 |
| 14 | 14.00 | 12.500 | 0.750 | 28.00 | 21.00 | 80 | 280.00 |
| 16 | 16.00 | 14.312 | 0.844 | 32.00 | 24.00 | 80 | 350.00 |
| 18 | 18.00 | 16.124 | 0.938 | 36.00 | 27.00 | 80 | 435.00 |
| 20 | 20.00 | 17.938 | 1.031 | 40.00 | 30.00 | 80 | 570.00 |
| 24 | 24.00 | 21.562 | 1.219 | 48.00 | 36.00 | 80 | 790.00 |
Schedule 160
| Nom. Pipe Size | Outside Diameter O.D. | Inside Diameter I.D. | Wall Thickness T | Center to Center V | Back to Face W | Pipe Schedule Number | Approx. Weight in Pounds Lbs. |
|---|---|---|---|---|---|---|---|
| 1 | 1.32 | 0.820 | 0.250 | 2.00 | 1.62 | 160 | 0.85 |
| 1¼ | 1.66 | 1.160 | 0.250 | 2.50 | 2.06 | 160 | 1.21 |
| 1½ | 1.90 | 1.338 | 0.281 | 3.00 | 2.44 | 160 | 1.82 |
| 2 | 2.38 | 1.692 | 0.344 | 4.00 | 3.19 | 160 | 3.51 |
| 2½ | 2.88 | 2.130 | 0.375 | 5.00 | 3.94 | 160 | 6.29 |
| 3 | 3.50 | 2.624 | 0.438 | 6.00 | 4.75 | 160 | 9.92 |
| 4 | 4.50 | 3.438 | 0.531 | 8.00 | 6.25 | 160 | 19.84 |
| 5 | 5.56 | 4.310 | 0.625 | 10.00 | 7.75 | 160 | 33.52 |
| 6 | 6.62 | 5.182 | 0.719 | 12.00 | 9.31 | 160 | 55.30 |
| 8 | 8.62 | 6.808 | 0.906 | 16.00 | 12.31 | 160 | 116.52 |
| 10 | 10.75 | 8.500 | 1.125 | 20.00 | 15.38 | 160 | 173.03 |
| 12 | 12.75 | 10.126 | 1.312 | 24.00 | 18.38 | 160 | 256.52 |
| 14 | 14.00 | 11.188 | 1.406 | 28.00 | 21.00 | 160 | 327.91 |
| 16 | 16.00 | 12.812 | 1.594 | 32.00 | 24.00 | 160 | 410.19 |
| 18 | 18.00 | 14.438 | 1.781 | 36.00 | 27.00 | 160 | 514.25 |
| 20 | 20.00 | 16.062 | 1.969 | 40.00 | 30.00 | 160 | 671.55 |
| 24 | 24.00 | 19.312 | 2.344 | 48.00 | 36.00 | 160 | 941.38 |
Schedule XXS
| Nom. Pipe Size | Outside Diameter O.D. | Inside Diameter I.D. | Wall Thickness T | Center to Center V | Back to Face W | Pipe Schedule Number | Approx. Weight in Pounds Lbs. |
|---|---|---|---|---|---|---|---|
| 1 | 1.32 | 0.604 | 0.358 | 2.00 | 1.62 | * | 0.93 |
| 1¼ | 1.66 | 0.896 | 0.382 | 2.50 | 2.06 | * | 1.33 |
| 1½ | 1.90 | 1.100 | 0.400 | 3.00 | 2.44 | * | 2.00 |
| 2 | 2.38 | 1.508 | 0.436 | 4.00 | 3.19 | * | 3.90 |
| 2½ | 2.88 | 1.776 | 0.552 | 5.00 | 3.94 | * | 6.92 |
| 3 | 3.50 | 2.300 | 0.600 | 6.00 | 4.75 | * | 10.91 |
| 4 | 4.50 | 3.152 | 0.674 | 8.00 | 6.25 | * | 21.83 |
| 5 | 5.56 | 4.060 | 0.750 | 10.00 | 7.75 | * | 36.87 |
| 6 | 6.62 | 4.892 | 0.864 | 12.00 | 9.31 | * | 60.83 |
| 8 | 8.62 | 6.870 | 0.875 | 16.00 | 12.31 | * | 128.18 |
| 10 | 10.75 | 8.750 | 1.000 | 20.00 | 15.38 | 140 | 190.33 |
| 12 | 12.75 | 10.750 | 1.000 | 24.00 | 18.38 | 120 | 282.17 |
Materials We Supply
180° Short Radius Return Bend to ASME B16.28 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 long and short radius return bend?
Centerline radius, and dat means the spacing between dem two legs. Long radius turns on 1.5 times the nominal diameter, and short radius on 1.0. Dat short pattern packs dem legs closer together for a tight coil pitch, but I tell you what, it comes at the cost of more turbulence through the turn.
How do I know which return bend pattern my coil needs?
The coil pitch usually fixes it right up. Compare the required centerline-to-centerline spacin' with the V dimension in the tables up above; the pattern whose V matches your design pitch is the one y'all need to order.
Are return bends made out of the same materials as elbows?
Yessir. Dem same ASTM A234, A403, A420 and alloy grades apply here too. Just holler with the size, schedule, and grade, and we'll let y'all know what we got sittin' on the shelf.
