Views: 3 Author: Site Editor Publish Time: 2025-06-30 Origin: Site
180 degree elbow, also known as a U-elbow or return elbow, is a pipe fitting that changes the direction of the fluid in a piping system by 180 degrees. In other words, it makes the fluid "turn around" and form a U-turn. In limited space or special system design, a 180-degree elbow can achieve the "return of the original path" of the fluid, which not only saves space but also improves the rationality and efficiency of the system. The 180-degree elbow is particularly suitable for pipeline designs with limited space or that require a compact layout. It can effectively optimize the direction of the pipeline and reduce the complexity of installation. 180 degree elbows are widely used in petrochemical, natural gas transmission, electric power, sewage treatment and other fields, providing reliable solutions for modern industrial pipeline projects. Contact us
Specification: | ASME B16.9 180 Deg Elbow |
Standard | EN, ISO, DIN, JIS, NPT |
Schedule: | Schedule 5 TO Schedule XXS. |
Size: | Normal Pipe Size (NPS) 1⁄₂ to Normal Pipe Size (NPS) 48” |
Type: | Butt Weld (BW), Seamless (SMLS) Welded |
Thickness: | Sch 5S, 20S, S10, S20, S30, 10S, S80, S100, S120, STD, 40S, S40, S60, XS, 80S, S140, S160, XXS and etc. |
Direction reversal: The main function is to completely reverse the direction of the fluid in the pipeline to achieve a 180-degree turn.
Compact structure: In terms of structure, the bending radius of the 180-degree elbow has a variety of specifications.
Reduce welds: The one-piece 180-degree elbow can reduce the number of welds, thereby reducing the risk of leakage and improving the reliability of the pipeline system.
Fluid resistance: Due to the large turning angle of the 180-degree elbow, the resistance encountered by the medium when flowing through is significantly greater than that of the small-angle elbow.
Wide range of connection methods: The 180-degree elbow has a variety of connection methods, including welding, flange connection, threaded connection, etc., which can be flexibly adapted to various pipeline systems.
Definition: The bending radius of a long radius 180° elbow is usually 1.5 times the nominal diameter of the pipe (i.e. R=1.5D, D is the nominal diameter of the pipe),
Bending radius R = 1.5 × D (D is the outer diameter of the pipe)
Features:
Smooth fluid transition, low resistance, reduced pressure drop
Uniform force on the pipe wall, suitable for high-speed fluid or high-pressure scenarios
Occupies a large space
Definition: Bending radius R = 1.0 × D
The bending radius of a short radius 180° elbow is generally 1 times the nominal diameter of the pipe (R=D)
Features:
Occupies a small space, compact structure
The fluid turns sharply, with large flow resistance and wear
Relatively low cost
Nominal Size | Outside Diameter at Bevel | Center to Center | Back to Face | |||
180 Returns | ||||||
DN | NPS | OD | O | K | ||
LR | SR | LR | SR | |||
15 | 1/2 | 21.3 | 76 | 48 | ||
20 | 3/4 | 26.7 | 76 | 51 | ||
25 | 1 | 33.4 | 76 | 51 | 56 | 41 |
32 | 1 1/4 | 42.2 | 95 | 64 | 70 | 52 |
40 | 1 1/2 | 48.3 | 114 | 76 | 83 | 62 |
50 | 2 | 60.3 | 152 | 102 | 106 | 81 |
65 | 2 1/2 | 73.0 | 190 | 127 | 132 | 100 |
80 | 3 | 88.9 | 229 | 152 | 159 | 121 |
90 | 3 1/2 | 101.6 | 267 | 178 | 184 | 140 |
100 | 4 | 114.3 | 305 | 203 | 210 | 159 |
125 | 5 | 141.3 | 381 | 254 | 262 | 197 |
150 | 6 | 168.3 | 457 | 305 | 313 | 237 |
200 | 8 | 219.1 | 610 | 406 | 414 | 313 |
250 | 10 | 273.0 |
| 508 | 518 | 391 |
300 | 12 | 323.8 | 914 | 609 | 619 | 467 |
350 | 14 | 355.6 | 1067 | 711 | 711 | 533 |
400 | 16 | 406.4 | 1219 | 813 | 813 | 610 |
450 | 18 | 457.0 | 1372 | 914 | 914 | 686 |
500 | 20 | 508.0 | 1524 | 1016 | 1016 | 762 |
550 | 22 | 559.0 | 1676 | 1118 | 1118 | 838 |
600 | 24 | 610.0 | 1829 | 1219 | 1219 | 914 |
Nominal Size | All Fittings | 180 Degree Elbow | ||||
DN | NPS | OD 3) 4) | ID 3) |
| K | U |
15-65 | 1/2 -21/2 | +1.6 | ± 0.8 | ± 6 | ± 6 | ± 1 |
80-90 | 3-31/2 | ± 1.6 | ± 1.6 | ± 6 | ± 6 | ± 1 |
100 | 4 | ± 1.6 | ± 1.6 | ± 6 | ± 6 | ± 1 |
125-200 | 5-8 | +2.4 | ± 1.6 | ± 6 | ± 6 | ± 1 |
250-450 | 10-18 | +4.0 | ± 3.2 | ± 10 | ± 6 | ± 2 |
500-600 | 20-24 | +6.4 | ± 4.8 | ± 10 | ± 6 | ± 2 |
ASME B16.9 180 degree elbows are classified by material including carbon steel, alloy steel, stainless steel, and duplex stainless steel.
Carbon Steel: ASTM A234 WPB/WPC, ASTM 420 WPL 3 / 6 / 9, A860 WPHY 42 / 46 / 56 / 60 / 65
Alloy Steel : ASTM A234 WP11 / WP12 / WP5 / WP9 / WP91 /
Stainless Steel : A403 WP304/304L/304H, WP316 / 316L, WP317, WP310S , WP321, WP347 ,WP904L
Duplex Stainless Steel : ASTM A815 S32205, S31803, 32750, 32760
Hot push molding: by heating the pipe at high temperature, push molding on the mold, applicable to carbon steel, stainless steel and other common materials, especially for large diameter elbow.
Cold bending process: direct bending by mechanical cold pressure, suitable for small diameter, high precision requirements of the pipe fittings.
Stamping and welding: two half-round stampings are welded into shape, suitable for thin-walled stainless steel, alloys and other special materials.
Mould pressing: suitable for mass production, high precision, widely used in standardized product manufacturing.
Heat exchangers and coils: in heat exchangers, 180 degree elbows are commonly used to connect U-shaped tube bundles, so that the fluid is folded back many times in the tube to increase the heat transfer area and efficiency.
Heating furnace and boiler: In the coil system of heating furnace and boiler, 180 degree elbow is used to realize multiple return of fluid to ensure that the fluid is fully heated in the furnace chamber.
Pipe Returns: When it is necessary to return piping 180 degrees in a limited space, such as in areas where equipment is connected and piping arrangements are restricted.
Fluid distribution and mixing: In some fluid distribution or mixing systems, 180-degree elbows can be used to direct fluids for specific paths.
Petroleum, chemical, and power industries: In these industries, 180 degree elbows are a common component of piping systems used to divert fluids in a variety of processes.
When selecting a 180 degree elbow, the following aspects should be considered:
Pipe size and pressure level: to ensure that the elbow size match and can withstand the system pressure.
Material selection: based on media corrosivity, temperature and other factors to choose the right material.
Bending radius: long radius is suitable for high flow rate requirements, short radius is suitable for limited space environment.
Connection: Welding connection is more solid, threaded connection is suitable for occasions with frequent maintenance and replacement.
Standard compliance: Ensure that the products comply with ASME, GB, ISO and other industry standards.
Supplier qualification: Choose regular manufacturers with pressure vessel production license or international certification.
