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Inox Steel India is a leading manufacturer and exporter of ASTM A691 Cr-Mo Alloy Steel SAW Pipes, engineered specifically for high-temperature, high-pressure, and high-stress environments. These pipes are widely used in power plants, boilers, refineries, petrochemical units, steam pipelines, and hydrogen/chemical processing systems.
ASTM A691 pipes are manufactured using submerged arc welding (SAW) of chromium-molybdenum alloy steel plates, followed by normalizing, tempering, or quench & temper heat treatment depending on the grade. They offer exceptional resistance to:
These qualities make A691 pipes indispensable for critical process systems where operational safety & reliability are non-negotiable.
ASTM A691 defines Submerged Arc Welded (SAW) pipes manufactured from Cr-Mo alloy steel plates, used where extreme heat and pressure performance is required.
Key Characteristics:
These pipes are essential for superheaters, reheaters, steam headers, boiler piping, refinery heaters, and petrochemical process lines.
✔ Single SAW Welded Pipes
Standard SAW longitudinal weld for general high-temperature use.
✔ Heat-Treated SAW Pipes
✔ 3LPE / Epoxy Coated SAW Pipes
For buried pipelines or corrosive environments.
| Grade | Composition Highlights | Typical Use |
|---|---|---|
| 1-1/4Cr–1/2Mo | Good creep resistance | Steam & boiler lines |
| 2 1/4Cr–1Mo | Better oxidation & strength | Hot hydrocarbon service |
| 5Cr–1/2Mo | Superior corrosion resistance | Refinery heaters & reactors |
| 9Cr–1Mo | Exceptional high-temp strength | Superheaters, HRSG, hydrogen lines |
The presence of chromium (Cr) improves oxidation & corrosion resistance, while molybdenum (Mo) enhances creep strength and high-temperature durability.
3️⃣ SAW Welding (Submerged Arc Welding)
4️⃣ Heat Treatment
Depending on grade & service:
6️⃣ Hydrostatic Pressure Testing
Guarantees pressure integrity and leak-proof performance.
7️⃣ Final Inspection & Marking
Size, grade, class, heat number, ASTM A691 marking.
Power Generation
Refineries
Petrochemical Plants
Chemical Industry
Oil & Gas
Industrial Boilers
ASTM A691 covers Submerged Arc Welded (SAW) alloy steel pipes manufactured from Cr-Mo (Chromium-Molybdenum) plates for use in high-temperature, high-pressure, and high-stress environments. These pipes are essential for critical pipelines where creep resistance, thermal stability, and weld integrity are mandatory.
Cr-Mo SAW pipes offer excellent performance in:
Inox Steel India manufactures fully certified A691 pipes with complete NDT, heat treatment charts, RT films, and mechanical test records, ensuring unmatched engineering reliability.
| Parameter / Property | ASTM A691 Cr-Mo Alloy Steel SAW Pipes | Standard Requirements – ASTM A691 |
|---|---|---|
| Material Type | Cr-Mo Alloy Steel | Alloy Steel SAW Pipes |
| Manufacturing Standard | ASTM A691 | ASTM A691 |
| Manufacturing Process | SAW (Submerged Arc Welded) | Mandatory SAW welding |
| Grades Available | 1-1/4Cr–1/2Mo, 2-1/4Cr–1Mo, 5Cr–1/2Mo, 9Cr–1Mo | All Cr-Mo grades |
| Heat Treatment | Normalized, Tempered, Quenched & Tempered | As per grade requirements |
| Applications | High temp & pressure service | Boiler, header, steam & refinery pipelines |
| Weld Integrity | High-strength SAW weld | Deep penetration weld |
| Mechanical Strength (TS) | ~485–655 MPa (grade-dependent) | As specified in ASTM |
| Yield Strength (YS) | ~275–450 MPa | As per grade |
| Temperature Resistance | 500°C–650°C | Suitable for high temp service |
| Corrosion Resistance | Excellent in hot fluids, steam | Depends on Mo and Cr content |
| OD Range | 16” – 60” (Custom) | Large-bore piping |
| Wall Thickness | SCH 20 – SCH 160 / Heavy Wall | As per specification |
| Testing Requirements | RT/UT, Hydro, Hardness, Impact | Mandatory NDT + Destructive tests |
| Coating Options | Black, Painted, Epoxy, 3LPE | Optional |
| Typical Industries | Power, Petrochemical, Refineries | High-temp pipelines |
| Documentation | MTC 3.1/3.2, RT films, HT charts | Required |
| HSN Code | 7305 / 7306 | SAW Alloy Steel Pipes |
Cr-Mo Alloy Steel Grades Under ASTM A691
Heat Treatment Conditions
| Grade | Temperature Range | Best Used For |
|---|---|---|
| 1-1/4Cr–1/2Mo | Up to ~500°C | Steam lines, moderate temp service |
| 2-1/4Cr–1Mo | Up to ~600°C | Power plants, boilers, HRSG, refinery piping |
| 5Cr–1/2Mo | Up to ~620°C | Hot hydrocarbon service, heater tubes |
| 9Cr–1Mo (Grade 91) | Up to ~650°C | Superheaters, hydrogen lines, high-stress pipelines |
Rule of Thumb:
More Mo = better high-temperature & creep strength
More Cr = better oxidation & corrosion resistance
| Parameter | Capability |
|---|---|
| Outside Diameter (OD) | 16” – 60” (Custom up to 80”) |
| Wall Thickness | SCH 20 – SCH 160 / Heavy-wall custom |
| Length | 6 m / 12 m / Long-length |
| Weld Type | Submerged Arc Welded (SAW) |
| Heat Treatment | N, NT, Q&T |
| Ends | Bevelled / Plain |
| Coatings | Black, Painted, Epoxy, 3LPE/3LPP |
| Grade | Price (INR/kg) | Price (USD/kg) |
|---|---|---|
| A691 1-1/4Cr–1/2Mo | ₹ 110 – ₹ 160 | $ 1.60 – $ 2.30 |
| A691 2-1/4Cr–1Mo | ₹ 140 – ₹ 190 | $ 1.95 – $ 2.75 |
| A691 5Cr–1/2Mo | ₹ 160 – ₹ 225 | $ 2.20 – $ 3.20 |
| A691 9Cr–1Mo (Grade 91) | ₹ 210 – ₹ 300 | $ 3.00 – $ 4.10 |
| Q&T Heat Treatment Addon | +₹ 12 – ₹ 35 | +$ 0.18 – $ 0.50 |
| 3LPE/3LPP Coating | +₹ 20 – ₹ 45 | +$ 0.25 – $ 0.60 |
Prices depend on OD, thickness, grade, heat treatment, testing level & documentation.
7305 / 7306 — Alloy Steel SAW Pipes
✔ Mandatory Tests (ASTM A691)
✔ Additional Tests (On Request)
✔ Documentation Provided
✔ Third-Party Inspection (TPI)
SGS • BV • DNV • TÜV • Lloyd’s Register
Inox Steel India exports ASTM A691 SAW Alloy Steel Pipes to:
Middle East:
Africa:
Europe:
Americas:
Asia Pacific:
Used in:
High-temperature and high-pressure pipelines demand deep-penetration weld strength, creep resistance, heat stability, and strict metallurgical control. Inox Steel India delivers ASTM A691 pipes that meet global engineering standards for critical installations.
✔ Why Engineers & EPC Companies Trust Us:
Inox Steel India is considered one of India’s most reliable suppliers of Cr-Mo alloy steel SAW pipes for mission-critical installations.
Power Plants & HRSG Systems
Refineries & Petrochemical Units
Refineries & Petrochemical Complexes
Chemical & Fertilizer Industries
Industrial Boilers
High-Stress Engineering Systems
ASTM A691 is chosen where reliability, temperature resistance, and long-term creep strength are engineering priorities.
Large-diameter Cr-Mo SAW pipes require careful handling and secure packaging.
✔ Standard Packing
✔ Heavy Industrial Packing
✔ Export Grade Packing
✔ Ports of Dispatch
JNPT • Mundra • Hazira • Chennai • Vizag
Looking for ASTM A691 Cr-Mo Alloy Steel SAW Pipes for boilers, power plants, refineries, petrochemical units, or high-temperature pipelines?
52-A, Mulji Thackersi Bldg, Islampura Street, Shop No. 10, Near Alankar Cinema, Mumbai – 400 004
alloy@inoxsteelindia.in
+91 9930796690
Inox Steel India
Email
Phone
→ Grade 22 (2-1/4Cr–1Mo): For boilers & refinery service up to ~600°C
→ Grade 91 (9Cr–1Mo): For superheater & ultra-high-temperature service (~650°C)
→ Yes — Q&T pipes are supplied for high-stress applications.
→ Up to 60” standard, 80” custom.
→ Yes — 3LPE, 3LPP, FBE, and epoxy coatings available as per project specification.
→ Yes — full QA documentation is supplied.
We offer engineering-grade pipes with full testing reports & global delivery.