45° LR butt weld elbows made to ASME B16.9 in stainless steel, duplex (S32205 / S31803), super duplex (S32750 / S32760), super austenitic and nickel alloy grades. Also supplied to MSS SP-43, EN 10253-4, DIN 2605, JIS B2313, GB/T 12459 and SH/T 3408 / 3409.
Seamless ½”–24″ (DN15–DN600) · Welded ½”–40″ (DN15–DN1000) · Sch 5S – XXS
What Is a 45° Butt Weld Elbow?
A 45° long radius (LR) butt weld elbow changes the direction of a pipeline by 45 degrees and is welded to the pipe at both ends. Its bend radius is 1.5 times the nominal pipe size (1.5D), and its center-to-end dimension (B) is fixed by ASME B16.9 — for example, NPS 4 has B = 64 mm and NPS 12 has B = 190 mm.
Compared with a short radius (1D) elbow, the long radius profile gives lower pressure drop and flow turbulence, which reduces wear in abrasive or high-velocity service. ASME B16.9 lists short radius elbows as 90° fittings; 90° LR and SR elbows are also available on request alongside this 45° fitting.
Butt weld ends are beveled 37.5° ±2.5° with a root face of 1.5 ±1.0 mm per ASME B16.9 Table 1, ready for matching pipe preparation. Every fitting is permanently marked with the manufacturer, ASTM/ASME grade (WP), schedule and nominal size — as shown in the reference photo of a super duplex ASTM A815 S32750 elbow, NPS 3 Sch 80S.
Key Specifications
| Product | 45° long radius butt weld elbow (90°, LR and SR available on request) |
|---|---|
| Size | Seamless: ½”–24″ (DN15–DN600) · Welded: ½”–40″ (DN15–DN1000) |
| Wall thickness | Sch 5S – Sch XXS |
| Standards | ASME B16.9, MSS SP-43, EN 10253-4, DIN 2605, JIS B2313, GB/T 12459, SH/T 3408, SH/T 3409 |
| Bend radius | 1.5D (long radius) |
| Materials | Stainless steel, duplex, super duplex, super austenitic, nickel alloy |
| End connection | Butt weld, bevel 37.5° ±2.5°, root face 1.5 ±1.0 mm (ASME B16.9 Table 1) |
| Marking | Manufacturer, ASTM/ASME grade (WP), schedule, nominal size |
Material Grades: Stainless Steel, Duplex, Super Duplex and Nickel Alloy Elbows
| Material family | Grades | Fitting specification |
|---|---|---|
| Stainless steel (austenitic) | 304 / 304L / 304H, 316 / 316L / 316H / 316Ti, 317L, 310S, 321 / 321H, 904L | ASTM A403 (WP) |
| Duplex stainless steel | S32205 (2205), S31803 | ASTM A815 (WPS) |
| Super duplex stainless steel | S32750 (2507), S32760 | ASTM A815 (WPS) |
| Super austenitic stainless steel | SMO 254 (S31254), AL-6XN (N08367) | ASTM A403 / B366 |
| Nickel alloys | Nickel 200 (N02200) / 201 (N02201), Monel 400 (N04400), Alloy 600 (N06600), 601 (N06601), 625 (N06625), Alloy 20 (N08020), Incoloy 800 / 800H / 800HT (N08800 / N08810 / N08811), 825 (N08825), Hastelloy C-22 (N06022), C-276 (N10276), B-2 (N10665), B-3 (N10675) | ASTM B366 (WP) |
Note: Super austenitic fittings (SMO 254, AL-6XN) are supplied to ASTM A403 or B366 depending on grade and size; nickel alloy fittings to ASTM B366. State the grade and UNS designation in your RFQ and the fitting specification will be confirmed with the quotation.
45° Elbow Dimensions and Wall Thickness (mm)
Center-to-end dimension B per ASME B16.9 Table 3. Tolerance on B is ±2 mm up to NPS 24. Wall thicknesses below are common schedule designations; intermediate and heavier walls are available on request.
| DN | NPS | OD (mm) | B, center-to-end (mm) | Sch 5S | Sch 10S | Sch 40S | Sch 80S |
|---|---|---|---|---|---|---|---|
| 15 | ½” | 21.3 | 16 | 1.65 | 2.11 | 2.77 | 3.73 |
| 20 | ¾” | 26.7 | 19 | 1.65 | 2.11 | 2.87 | 3.91 |
| 25 | 1″ | 33.4 | 22 | 1.65 | 2.77 | 3.38 | 4.55 |
| 32 | 1¼” | 42.2 | 25 | 1.65 | 2.77 | 3.56 | 4.85 |
| 40 | 1½” | 48.3 | 29 | 1.65 | 2.77 | 3.68 | 5.08 |
| 50 | 2″ | 60.3 | 35 | 1.65 | 2.77 | 3.91 | 5.54 |
| 65 | 2½” | 73.0 | 44 | 2.11 | 3.05 | 5.16 | 7.01 |
| 80 | 3″ | 88.9 | 51 | 2.11 | 3.05 | 5.49 | 7.62 |
| 90 | 3½” | 101.6 | 57 | 2.11 | 3.05 | 5.74 | 8.08 |
| 100 | 4″ | 114.3 | 64 | 2.11 | 3.05 | 6.02 | 8.56 |
| 125 | 5″ | 141.3 | 79 | 2.77 | 3.4 | 6.55 | 9.53 |
| 150 | 6″ | 168.3 | 95 | 2.77 | 3.4 | 7.11 | 10.97 |
| 200 | 8″ | 219.1 | 127 | 2.77 | 3.76 | 8.18 | 12.7 |
| 250 | 10″ | 273.0 | 159 | 3.4 | 4.19 | 9.27 | 12.7 |
| 300 | 12″ | 323.8 | 190 | 3.96 | 4.57 | 9.53 | 12.7 |
| 350 | 14″ | 355.6 | 222 | 3.96 | 4.78 | 9.53 | 12.7 |
| 400 | 16″ | 406.4 | 254 | 4.19 | 4.78 | 9.53 | 12.7 |
| 450 | 18″ | 457 | 286 | 4.19 | 4.78 | 9.53 | 12.7 |
| 500 | 20″ | 508 | 318 | 4.78 | 5.54 | 9.53 | 12.7 |
| 550 | 22″ | 559 | 343 | 4.78 | 5.54 | 9.53 | 12.7 |
| 600 | 24″ | 610 | 381 | 5.54 | 6.35 | 9.53 | 12.7 |
Larger sizes: welded elbows up to 40″ (DN1000), Sch 160 / XXS walls and special dimensions are available on request against drawings or the ASME B16.9 dimension tables.
Engineering Drawing — 45° LR Elbow (ASME B16.9)
The drawing shows the 45° LR elbow geometry: center-to-end dimension B (listed in the table for each NPS), bend radius R = 1.5D, wall thickness t, outside diameter OD and the 37.5° ±2.5° butt weld end bevel with 1.6–2.2 mm root face. Marking example: ELBOW 45DEG LR ASME B16.9 · ASTM A403 WP304/304L · 2″ SCH40 · Ø60.3×3.91 · HEAT NO. XXXXXX.
Reference dimensions B for NPS 1–24 match the ASME B16.9 Table 3 values (e.g. NPS 1: B = 22 mm / 1-1/8 in; NPS 2: B = 35 mm / 1-3/8 in; NPS 4: B = 64 mm / 4-1/2 in; NPS 12: B = 190 mm / 7-1/2 in). Tolerances per ASME B16.9.
Why Choose Duplex, Super Duplex and Nickel Alloy Elbows
- Stainless steel elbows (304L, 316L, 321, 904L): general corrosion resistance for water, food, pharma and chemical lines.
- Duplex elbows (S32205 / S31803): about twice the yield strength of 316L, with good resistance to chloride stress corrosion cracking.
- Super duplex elbows (S32750 / S32760): PREN above 40, for seawater, offshore, desalination and high-chloride process lines.
- Nickel alloy elbows (Alloy 625, C-276, C-22, 825, 400): for strong acids, high temperature and severe corrosive media.
Applications
Oil and gas, offshore and subsea, marine and desalination, chemical and petrochemical, power generation, pulp and paper, food, beverage and pharmaceutical, heat exchangers and boilers, flue gas desulfurization, and new energy projects.
How to Order
Please send: material grade, size (NPS/DN), schedule or wall thickness, angle and radius (45° LR), standard, quantity and any special requirements (testing, certificates, marking). We reply with a quotation promptly.
Need a Quote for 45° Elbows?
Send the material grade, size (NPS/DN), schedule, standard and quantity — you will receive a written quotation stating the specification edition, delivery condition, documents included and lead time.
FAQ: 45° Butt Weld Elbows
What is a 45° long radius (LR) butt weld elbow?
A 45° LR elbow changes the direction of a pipeline by 45 degrees and is welded to the pipe at both ends. Its bend radius is 1.5 times the nominal pipe size (1.5D), and its center-to-end dimension (B) is fixed by ASME B16.9. For example, NPS 4 has B = 64 mm and NPS 12 has B = 190 mm.
What is the difference between a long radius and a short radius elbow?
A long radius elbow has a bend radius of 1.5D and gives lower pressure drop and flow turbulence. A short radius elbow has a bend radius of 1D, so it fits tighter spaces but creates more pressure drop. ASME B16.9 lists short radius elbows as 90° fittings.
Which material should I choose: stainless steel, duplex, super duplex or nickel alloy?
Austenitic grades such as 304L and 316L suit general corrosion service. Duplex S32205 adds higher strength and better chloride stress corrosion resistance. Super duplex S32750 and S32760 (PREN above 40) are widely used for seawater, offshore and high-chloride service. Nickel alloys such as Alloy 625, C-276 and Alloy 825 are chosen for strong acids, high temperature or severe corrosion. Final selection depends on your medium, temperature and design code.
What sizes and wall thicknesses are available?
Seamless 45° elbows are supplied from ½” to 24″ (DN15–DN600); welded elbows from ½” to 40″ (DN15–DN1000). Wall thickness ranges from Sch 5S to Sch XXS. Special sizes and thicknesses are available by agreement.
What is the pressure rating of an ASME B16.9 elbow?
ASME B16.9 does not give a separate pressure class. The rating is calculated as for seamless pipe of the same material, size and wall thickness, according to the applicable ASME B31 code. For this reason the pipe size, schedule and material grade are marked on the fitting instead of a pressure rating.
Are the elbows hydrostatically tested?
ASME B16.9 does not require production hydrostatic testing, but every fitting must be capable of withstanding the test pressure that the piping code requires for matching seamless pipe, without leakage. Contact us if your project specification requires a hydrotest or other additional tests.
What markings do the fittings carry?
Each fitting is permanently marked with manufacturer name or trademark, ASTM/ASME material grade, schedule number or wall thickness, and nominal size. The prefix “WP” in the grade marking certifies manufacture to ASME B16.9.
