The ASTM A691 1-1/4Cr-1/2Mo EFW Alloy Steel Pipes are designed to be used in power stations, refineries, petrochemical units and processes in which they are subjected to high temperature and pressure. The pipes made using the Electric Fusion Welding (EFW) method have the property of being strong, durable and resistant to oxidation. The chromium-molybdenum composition enhances the high temperature strength and creep resistance, compared with conventional carbon steel pipes. ASTM A691 1-4/12Cr pipes are offered in many sizes, wall thickness and pressure classes for different requirements of a project. These are installed in boilers, pressure vessels, heat exchangers and high pressure pipes. Amardeep Steel is an ASTM A691 1-1/4Cr-1/2Mo Alloy Steel Pipe Manufacturer and Supplier in India.
Technical Data
Specifications of ASTM A691 1-1/4Cr-1/2Mo EFW Alloy Steel Pipe
| Attribute / Parameter | Specification Details |
|---|---|
| Standard Specification | ASTM A691 / ASME SA691 |
| Grade Designation | Grade 1-1/4Cr (1.25% Chromium, 0.5% Molybdenum) |
| Base Material Standard | ASTM A387 / A387M Grade 11 Class 1 or Class 2 (Pressure Vessel Plate) |
| Manufacturing Process | Electric-Fusion-Welded (EFW) with added filler metal |
| Welding Types | Straight Seam Longitudinal (LSAW) / Spiral Welded (SSAW) |
| Available Classes | Class 10, 11, 12, 13, 20, 21, 22, 23, 30, 31, 32, 33, 40, 41, 42, 50, 60, etc. |
| Size Range (Outer Diameter) | 16″ NB to 60″ NB (457 mm to 1422 mm); custom smaller/larger sizes available |
| Wall Thickness | 2 mm to 60 mm (Up to 3″ / 75 mm thickness) |
| Schedules | SCH 10, SCH 20, SCH 30, SCH 40, SCH STD, SCH 80, SCH XS, SCH 120, SCH 160, SCH XXS |
| Pipe Length | Single Random, Double Random, Standard 6m / 12m, or Cut Lengths |
| End Connections | Plain End (PE), Beveled End (BE), Threaded |
| Surface Finish | Black Painted, Anti-Corrosion Varnish, Bare, 3PE, FBE Coated |
| Certifications & Testing | IBR (Indian Boiler Regulations) Form 3A/3D, NACE MR0175, MTC EN 10204 3.1/3.2, Radiographic Test (RT) |
Chemical Compositions of ASTM A691 1-1/4Cr-1/2Mo EFW Alloy Steel Pipe
| Element | Carbon (C) | Manganese (Mn) | Phosphorus (P) | Sulfur (S) | Silicon (Si) | Chromium (Cr) | Molybdenum (Mo) |
|---|---|---|---|---|---|---|---|
| Content (%) | 0.05 – 0.17 | 0.40 – 0.65 | ≤ 0.025 | ≤ 0.025 | 0.50 – 0.80 | 1.00 – 1.50 | 0.45 – 0.65 |
ASTM A691 1-1/4Cr-1/2Mo EFW Alloy Steel Pipe Mechanical Properties
| Property | Value |
|---|---|
| Tensile Strength | 515–690 MPa (75–100 ksi) |
| Yield Strength (min) | 310 MPa (43 ksi) |
| Elongation (min, 2 in. / 50 mm) | 18% |
| Hardness (max) | 201 HB |
| Max Operating Temp | 565°C / 1050°F |
Applications Uses of ASTM A691 1-1/4Cr-1/2Mo EFW Alloy Steel Pipe
- Power Generation
- Petrochemical
- Oil & Gas
- Refinery
- Chemical Processing
- Boiler Manufacturing
- Heat Exchanger Manufacturing
- Pressure Vessel Manufacturing
Frequently Asked Questions
What is ASTM A691 1-1/4Cr-1/2Mo EFW Alloy Steel Pipe?
ASTM A691 1-1/4Cr-1/2Mo EFW Alloy Steel Pipe is an electric fusion welded alloy steel pipe designed for high-temperature and high-pressure service.
What are ASTM A691 1-1/4Cr-1/2Mo EFW Pipes used for?
They are used in power plants, refineries, petrochemical plants, boilers, heat exchangers, and high-temperature process piping.
What is the difference between ASTM A691 1-1/4Cr and 2-1/4Cr pipes?
The main difference is chromium content. 2-1/4Cr contains more chromium, providing greater resistance to oxidation and high-temperature degradation than 1-1/4Cr.
Is ASTM A691 1-1/4Cr-1/2Mo suitable for high-temperature and high-pressure applications?
Yes. These pipes are designed for elevated-temperature and high-pressure applications where strength and thermal stability are required.
What standards and specifications apply to ASTM A691 1-1/4Cr EFW Pipes?
They are manufactured according to ASTM A691 specifications and may also be supplied to the corresponding ASME SA691 requirements.
Is ASTM A691 1-1/4Cr Pipe suitable for boiler and power plant applications?
Yes. They are suitable for boiler, steam, and high-temperature piping systems used in power generation facilities.
