ASTM A234 WP11-S 180 Degree U Bend For High Temperature And Pressure Application
Product Specifications
| Product Name | 180 Degree Return Bend |
| Specification | ASTM A234 |
| Material | WP11-S |
| Radius | LR or SR (Depend on Customer's Requirements) |
| Surface | Black Painted or Oiled |
| Test | Size Inspection, Visual Inspection, NDE Test |
| Size Standard | ASME B16.9 |
| Application | Heat Exchangers, Piping Systems, Oil and Gas Industry, Water Treatment |
Product Description
A 180-degree U-bend is a pipe fitting that curves back on itself in a semi-circular or U-shaped pattern, changing the flow direction by 180 degrees. It is commonly used in piping systems where space constraints or thermal expansion management require a tight directional reversal.
Key Features
- Shape & Geometry: Forms a complete half-circle (U-shape) with specified bend radius (R) as a multiple of pipe diameter
- Types: Short Radius (1D) for tight spaces, Long Radius (1.5D+) for smoother flow, or custom engineered radii
- Manufacturing: Hot induction bending for thick walls, cold bending for smaller pipes, or mandrel bending for smooth interiors
- Materials: Carbon steel, alloy steel (ASTM A234 WP11), stainless steel, or nickel alloys
- End Connections: Plain ends for welding, beveled ends for butt welding, or threaded ends for screw connections
Advantages vs. Two 90° Bends: Fewer welds reduce leak risks, lower pressure drop for smoother flow, and more compact design for tight spaces.
ASTM A234 WP11 Chemical Composition (%)
| Element | WP11 Class 1 | WP11 Class 2 | WP11 Class 3 |
| Carbon (C) | 0.05-0.15 | 0.05-0.20 | 0.05-0.20 |
| Manganese (Mn) | 0.30-0.60 | 0.30-0.80 | 0.30-0.80 |
| Phosphorus (P) | ≤ 0.030 | ≤ 0.030 | ≤ 0.030 |
| Sulfur (S) | ≤ 0.030 | ≤ 0.030 | ≤ 0.030 |
| Silicon (Si) | 0.50-1.00 | 0.50-1.00 | 0.50-1.00 |
| Chromium (Cr) | 1.00-1.50 | 1.00-1.50 | 1.00-1.50 |
| Molybdenum (Mo) | 0.44-0.65 | 0.44-0.65 | 0.44-0.65 |
| Nickel (Ni) | ≤ 0.50 | ≤ 0.50 | ≤ 0.50 |
| Vanadium (V) | - | - | ≤ 0.03 |
| Columbium (Cb) | - | - | ≤ 0.08 |
ASTM A234 WP11 Mechanical Properties
| Property | WP11 Class 1 | WP11 Class 2 | WP11 Class 3 |
| Tensile Strength (MPa) | ≥ 415 | ≥ 485 | ≥ 485 |
| Yield Strength (MPa) | ≥ 205 | ≥ 275 | ≥ 275 |
| Elongation (%) (min) | 20 | 20 | 20 |
| Hardness (HB) (max) | 197 | 197 | 197 |
Notes: WP11 Class 1 is standard grade, while Classes 2 & 3 offer higher strength through modified heat treatment (Class 3 includes micro-alloying elements). Suitable for high-temperature service up to 593°C (1100°F).
Applications
- Power Plants: Boiler systems, steam lines, and thermal expansion loops
- Oil & Gas Refineries: Crude oil processing and high-pressure gas lines
- Chemical Plants: Resistant to sulfur compounds and acidic/alkaline environments
- Steam Systems: Steam distribution networks up to 593°C
- Heating/Cooling: Heat recovery systems and condensers
