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Inox Steel India supplies a complete range of high-temperature, high-pressure, and severe-corrosion-resistant materials required for refinery & petrochemical process units.
Refineries operate under extreme thermal, pressure, chemical, and corrosion conditions, especially in:
This makes material selection absolutely critical.
To match these conditions, Inox Steel India offers the three essential refinery-grade materials:
🔸 A335 (P11 / P22 / P91) : For high-temperature steam, furnace lines, reformer coils, boiler lines.
🔸 A312 (304 / 316 / 316L): For corrosive fluids, utility service, condensate, overhead lines.
🔸 B444 (Inconel 625): For chlorides, sour gas (H₂S), extreme corrosion, high-temperature oxidation.
Together, these materials cover 90% of refinery & petrochemical piping requirements.
✔ 1. High Temperature (400°C–1200°C)
Refineries use steam, reformer gas, furnace heating, catalytic cracking, and thermal processes.
This requires materials with:
A335 P22 & P91 dominate this zone.
✔ 2. Highly Corrosive Fluids
Fluids contain:
A312 (316L) and B444 (Inconel 625) are mandatory.
✔ 3. Hydrogen / Sour Gas (H₂S)
Hydrogen cracking, sulphide stress corrosion cracking (SSCC), and embrittlement can occur.
Only Alloy 625 (B444) withstands this safely.
✔ 4. High Pressure & Shock Loads
Steam surges, pressure pulsations, furnace firing cycles → need seamless pipes with heavy schedules.
A335 P-Grades handle this.
✔ 5. Multi-Service Compatibility
Refineries often have mixed service:
A combination of A335, A312, and B444 makes pipelines safe and long-lasting.
🔥 FCC (Fluid Catalytic Cracking Unit)
🌡 Crude Distillation Unit (CDU)
🛢 Hydrotreater / Hydrocracker
🔥 Reformer Unit
💨 Steam Systems
🧪 Chemical Units
This is why choosing the right material (and the right supplier) is critical.
Inox Steel India ensures:
| Material | Standard | Grades | Purpose in Refinery |
|---|---|---|---|
| A335 Alloy Steel | ASTM A335 | P11 / P22 / P91 | High-temperature steam, heater coils, reformer lines, boiler lines |
| A312 Stainless Steel | ASTM A312 | 304 / 316 / 316L | Corrosive media, utility service, condensate, moderate temp fluids |
| B444 Inconel | ASTM B444 | Inconel 625 (UNS N06625) | High-chloride, high-sulphur, sour gas, high-temp oxidation, severe corrosion |
A335 P11 / P22 / P91 — High-Temperature Cr-Mo Alloy Steel
| Property | P11 | P22 | P91 |
|---|---|---|---|
| Chromium (Cr) | 1.0% | 2.25% | 9% |
| Molybdenum (Mo) | 0.5% | 1.0% | 1% |
| Temp Range | 450–550°C | 520–600°C | 600–700°C |
| Creep Strength | Medium | High | Ultra High |
| Pressure Capability | High | High | Very High |
| Delivery Cond. | N+T | N+T | Q+T |
| Typical Uses | Reformer lines, HP steam | Heater coils, reheat lines | Main steam, ultra-steam |
A312 TP304 / TP316L — Corrosion & Condensate Service
| Property | TP304 | TP316L |
|---|---|---|
| Ni | 8–11% | 10–14% |
| Cr | 18–20% | 16–18% |
| Mo | — | 2–3% |
| Corrosion Resistance | High | Very High |
| Chloride Resistance | Medium | High |
| Temp Range | Up to 650°C | Up to 650°C |
| Uses | Utility lines | Condensate, wet chlorine, acidic services |
ASTM B444 — INCONEL 625 (UNS N06625)
| Property | Value |
|---|---|
| Ni Content | 58% minimum |
| Cr Content | 20–23% |
| Mo Content | 8–10% |
| Nb Content | 3.1–4.1% |
| Yield Strength | 350+ MPa |
| Tensile Strength | 690+ MPa |
| Temp Capability | Up to 1090°C |
| Corrosion Resistance | Exceptional |
| Chloride Stress Cracking | Excellent resistance |
| Sour Gas / H2S | Excellent |
| Pitting / Crevice Corrosion | Excellent |
| Oxidation Resistance | Outstanding |
Where B444 Is Used in Refineries
| Material | Sizes | Schedules |
|---|---|---|
| A335 (P-Grades) | ½” – 26” | SCH 40 / SCH 80 / SCH 160 / XXS |
| A312 (SS) | ½” – 24” | SCH 10S / 40S / 80S |
| B444 (Inconel 625) | ½” – 8” | SCH 40 / SCH 80 |
A335
A312
B444 (Inconel 625)
| Service | Recommended Material |
|---|---|
| High-temperature steam | A335 P22 / P91 |
| Reheater / Superheater | A335 P91 |
| Reformer gas lines | A335 P22 / P91 |
| Condensate & utility | A312 TP304 / TP316L |
| Sour gas / H2S | B444 Inconel 625 |
| High-chloride overhead lines | B444 / 316L |
| Crude oil heater coils | A335 P22 |
| Hydrocracker units | B444 / Alloy 625 |
| FCC units | A335 + B444 (mixed) |
Refinery & petrochemical plants contain complex interlinked services. Each requires specific metals for safety & longevity.
High Temperature / High Pressure Service (Furnaces, Reformers, Boilers, HCU, FCC)
✔ A335 P11 / P22 / P91
Used in services such as:
Corrosive / Chloride / Condensate / Wet Hydrocarbon Service
✔ A312 304 / 316 / 316L
Selected for:
Severe Corrosion, Sour Gas (H₂S), High Sulphur, High Chloride Service
✔ B444 (Inconel 625 / UNS N06625)
Ideal for:
A335 (P11 / P22 / P91) — Seamless Alloy Steel
| OD Range | ½” – 26” |
| Schedules | SCH 40, SCH 80, SCH 160, XXS |
| Manufacturing | Seamless Only |
| Delivery | N+T (P11/P22), Q+T (P91)
A312 (304 / 316L) — Stainless Steel
| OD Range | ½” – 24” |
| Schedules | SCH 10S, 40S, 80S |
| Delivery | Annealed / Pickled
B444 (Inconel 625) — Nickel Alloy
| OD Range | ½” – 8” |
| Schedules | SCH 40, SCH 80 |
| Delivery | Solution Annealed
A335 — Common Refinery Steam Sizes
| NB | OD (mm) | SCH 80 WT | SCH 160 WT | XXS WT |
|---|---|---|---|---|
| 2″ | 60.3 | 5.54 | 8.74 | 15.09 |
| 3″ | 88.9 | 7.62 | 11.13 | 18.26 |
| 4″ | 114.3 | 8.56 | 13.49 | 21.95 |
| 6″ | 168.3 | 10.97 | 18.26 | 28.58 |
| 8″ | 219.1 | 12.70 | 23.01 | 33.32 |
A312 — Refinery Condensate/Utility Sizes
| Size | OD | SCH 10S | SCH 40S |
|---|---|---|---|
| 1″ | 33.4 | 2.77 | 3.38 |
| 2″ | 60.3 | 2.77 | 3.91 |
| 3″ | 88.9 | 3.05 | 5.49 |
| 4″ | 114.3 | 3.05 | 6.02 |
B444 — Nickel Alloy Critical Service Sizes
| Size | OD | SCH 40 | SCH 80 |
|---|---|---|---|
| 1″ | 33.4 | 3.38 | 4.55 |
| 2″ | 60.3 | 3.91 | 5.54 |
| 3″ | 88.9 | 5.49 | 7.62 |
These sizes are used heavily in HCU, FCC, CDU overhead, sour gas headers, and H₂S-rich lines.
Indicative Price List (INR + USD)
(Prices vary with nickel, molybdenum & chromium market)
A335 Alloy Steel (P-Grades)
| Grade | Schedule | INR/kg | USD/kg |
|---|---|---|---|
| P11 | SCH 40/80 | ₹ 240 – ₹ 320 | $3.10 – $4.20 |
| P22 | SCH 80 | ₹ 260 – ₹ 350 | $3.50 – $4.60 |
| P91 | SCH 160/XXS | ₹ 450 – ₹ 700 | $6.00 – $9.30 |
A312 Stainless Steel
| Grade | Schedule | INR/kg | USD/kg |
|---|---|---|---|
| 304/304L | SCH 10/40 | ₹ 260 – ₹ 340 | $3.40 – $4.30 |
| 316/316L | SCH 10/40 | ₹ 310 – ₹ 390 | $4.10 – $5.20 |
B444 (Inconel 625)
| Grade | Schedule | INR/kg | USD/kg |
|---|---|---|---|
| Alloy 625 | SCH 40/80 | ₹ 2,500 – ₹ 3,800 | $35 – $55 |
B444 pricing changes frequently due to Ni/Mo volatility.
A335 (P11/P22/P91)
A312 (304/316L)
B444 (Inconel 625)
Documentation Supplied (Refinery Project Requirement)
Value-Added Services for Refinery EPC & Shutdowns
Refinery & petrochemical plants operate under some of the harshest conditions in the process industry. They involve:
This makes material selection the single most critical factor. Inox Steel India supplies the three refinery-essential pipe families:
✔ A335 (P11 / P22 / P91)
→ High-temperature, high-pressure steam, furnace, reformer & heater lines.
→ Used in FCC, CDU heaters, reformer, boilers, HRSG, HCU.
✔ A312 (304/316/316L)
→ Corrosive, condensate, wet hydrocarbon, overhead & utility lines.
✔ B444 (Inconel 625)
→ Sour service (H₂S), chloride-rich overhead lines, high-sulphur crude, high-temperature corrosion.
These three categories together solve 90% of refinery & petrochemical piping requirements.
🔥 FCC Unit (Fluid Catalytic Cracking)
🛢 CDU / VDU (Crude & Vacuum Distillation)
🏭 Hydrocracker (HCU) & Hydrotreaters (HDS/HDN)
🔥 Reformer / Hydrogen Generation
🧪 Petrochemical & Chemical Plants
🌡 Boiler & HRSG Steam Networks
Inox Steel India is trusted by EPC contractors, boiler manufacturers, steam system integrators, and refinery shutdown teams.
Inox Steel India supplies refinery & petrochemical-grade piping to:
We hold ready stock of:
For shutdowns, revamps & ongoing projects.
🌍 Export Capabilities — Global Refinery Supply
We export refinery-grade piping to:
UAE • Saudi Arabia • Oman • Kuwait • Bahrain
South Africa • Egypt • Kenya • Nigeria
Malaysia • Indonesia • Thailand • Singapore
Italy • Spain • Poland • Netherlands • UK
USA • Canada • Mexico
All materials are shipped with full traceability and heat number documentation.
Refinery-grade piping requires high-protection packaging:
✔ For A335 (P22/P91)
✔ For A312 (316L)
✔ For B444 (Inconel 625)
Because Nickel alloys are expensive and corrosion-sensitive:
We help EPCs and shutdown contractors with:
Inox Steel India supplies fully certified A335, A312 & B444 refinery-grade pipes for:
52-A, Mulji Thackersi Bldg, Islampura Street, Shop No. 10, Near Alankar Cinema, Mumbai – 400 004
alloy@inoxsteelindia.in, steel@inoxsteelindia.in
+91 9930796690
Condensate, overhead water wash lines, reflux lines, utility lines, cooling water.
Sour gas (H₂S), chlorides, high-sulphur crude, FCC overhead, hydrocracker units.
Yes — mandatory for verifying correct metallurgy.
316L is — 304 is not recommended for high-chloride fluids.
Yes — MTC 3.1/3.2, PMI, NDT, hydro, HT chart, packing list, TPI reports.
Yes — A335/A312 always in stock; B444 on priority basis.
Inox Steel India supplies A335 P11/P22/P91 alloy steel, A312 304/316L stainless steel, and B444 Inconel 625 pipes for refinery & petrochemical service. Ideal for sour gas, high temperature, chlorides, overhead lines, FCC, HCU, CDU, and hydrotreating units. TPI-certified, export-ready.