A Gulf Coast sulfuric acid plant endured $1.8M losses from 304L tube ruptures in 93% H2SO4 at 350°F-Incoloy 825 hollow bars eliminated recurrence, saving 28% on material costs.
Standard stainless steels corrode 100x faster in hot sulfuric acid, causing 35% of chemical industry heat exchanger failures. Incoloy Hollow Bars, led by UNS N08825 per ASTM B564, provide economical, high-integrity alternatives with seamless construction.
These nickel-iron-chromium alloys target OEM manufacturers, fabricators, procurement heads, and supply stores in chemical processing, oil & gas, marine, pharma, and power generation. DIN 2.4858 compliant, they balance performance and price. Technical details follow.
Incoloy Hollow Bars conform to essential pressure vessel and corrosion standards:
Requires stabilization annealing at 1800°F for carbide precipitation resistance.
A specification is written for a product form. The standards below are the ones that cover rod and bar; the plate, bar and tube specifications for these grades are different documents and are listed on their own pages.
| Grade | UNS | Rod and bar specification |
|---|---|---|
| DS | N08330 | ASTM B511 / B512 |
| 800 | N08800 | ASTM B408 |
| 800H | N08810 | ASTM B408 |
| 800HT | N08811 | ASTM B408 |
| 825 | N08825 | ASTM B425 / B564 |
| 890 | N08890 | ASTM B408 |
| 903 | N19903 | Mill specification |
| 909 | N19909 | AMS 5892 / 5884 |
| 925 | N09925 | NACE MR-01-75 / ASME CC 2218 / HA46 |
| 945 | N09945 | NACE MR0175 / ISO 15156-3 / HA 119 |
| 660 (A286) | S66286 | ASTM A638 / ASME SA-638 / AMS 5731 / 5732 / 5734 / 5737 |
Incoloy Hollow Bars provide tubing performance in machinable bar stock:
Ideal companion to Incoloy hex bar for manifold components. Mumbai stock for global export.
Incoloy 825 hollow bars (UNS N08825) excel in sulfuric acid heat exchangers, sour gas flowlines, marine condensers. ASTM B564 seamless construction handles 93% H2SO4 to 400°F where 316L fails rapidly. OEMs prefer cost-effective high-pressure tubing replacement.
825 offers 250x better corrosion rate in hot H2SO4 (2 vs 500 MPY), PREN 31 vs 19 for chlorides. Higher strength, weldable with matching filler. Cost premium justified by 10x service life in chemical processing per field data.
OD 25–350mm, ID 15-300mm, walls 4-25mm, lengths 4-10m standard. Custom trepanned or bored from solid per ASTM B564 tolerances. Annealed condition for machining; available polished for pharma. Mumbai suppliers stock common sizes.
Yes, UNS N08825 meets NACE MR0175/ISO 15156 limits (≤ 28 HRC annealed). Proven in H2S partial pressures to 0.1 bar at 177°C. Superior to 13Cr martensitics for deep sour gas wells.
100% ultrasonic per ASTM A388, hydrostatic to code pressures, PMI, intergranular corrosion ASTM A262 Practice E, tensile/impact testing. EN 10204 3.2 certification includes chemistry verification and heat treatment records for full traceability.
We ship worldwide from Mumbai. See every destination we export to on our export markets page.
We deliver across India from our Mumbai stockyard. See every city we supply on our supply locations page.
UNS N08825 Incoloy Hollow Bars deliver proven sulfuric acid resistance at stainless-like pricing, slashing total cost of ownership 40% in chemical and oilfield service. ASTM B564 quality and NACE compliance build procurement trust worldwide.
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