Description
Ni-Fe-Cr-Mo-Cu-Ti corrosion-resistant alloy
Incoloy 825 Threaded Rod
Corrosion-resistant nickel-iron-chromium threaded bar for acid processing, oil and gas, pollution control and chemical equipment.
Product overview
Incoloy 825 threaded rod is made from UNS N08825 nickel-iron-chromium alloy with molybdenum, copper and titanium additions. The alloy is selected for resistance in many sulfuric and phosphoric acid, sour oil-and-gas and chloride-bearing process environments.
ASTM B425 is commonly specified for Alloy 825 rod and bar. A finished threaded-rod order should state the condition, mechanical requirements, thread standard, size, length, surface finish, mating hardware and alloy-verification plan.
Incoloy 825 threaded rod specifications
| Material designation | Alloy 825 / UNS N08825 / EN 2.4858 |
|---|---|
| Starting material | ASTM B425 rod and bar, ordered condition |
| Thread systems | ASME B1.1 UNC, UNF or 8UN; ASME B1.13M / ISO metric |
| Size range | 1/4–3 in and M6–M72 typical; larger sizes subject to mill availability |
| Length | Stock or cut-to-length threaded bar |
| Surface | Clean machined, pickled/passivated or specified finish |
| Matching hardware | Alloy 825 or engineer-approved compatible nuts and washers |
| Inspection | EN 10204 3.1, PMI, dimensions, thread gauges and tests as ordered |
Final dimensions, tolerances, heat treatment, coating, testing and acceptance criteria follow the confirmed purchase order and the applicable standard edition. Availability depends on diameter, length, thread form and production quantity.
Why specify this material?
Alloy 825 is considered when acid resistance and chloride performance are needed with practical nickel-alloy fabrication. Detailed media chemistry and temperature should be compared against C276, Alloy 625, Alloy 20 and duplex stainless options.
Engineering note
Confirm resistance using the actual process stream, including oxidizing ions, solids, aeration and shutdown conditions. Anti-galling, lubricant compatibility and galvanic coupling must be addressed for the complete bolted joint.
Typical applications
Quality, inspection and documentation
Alloy 825 threaded rod should retain heat traceability from ASTM B425 starting material through machining. PMI, surface cleanliness, dimensional results and anti-galling provisions should be included in the final inspection plan.
- EN 10204 3.1 material test certificate
- Heat-number and batch traceability
- Chemical composition and mechanical properties
- Dimensional inspection and thread gauging
- PMI for stainless and nickel alloys when ordered
- Coating thickness or surface inspection when applicable
- Third-party inspection and additional testing by agreement
- Export marking and seaworthy packing
Information required for quotation
- Material grade, governing material/bolting standard and required edition
- Diameter, thread series, pitch and thread class or tolerance
- Overall length, cut-end requirements and quantity
- Heat treatment, surface finish or coating system
- Matching nuts and washers, including anti-galling requirements
- Inspection plan, MTC, PMI, NDE and third-party witness requirements
- Delivery destination, packaging and required schedule
Frequently asked questions
Which standard covers Incoloy 825 rod and bar?
ASTM B425 is commonly used for UNS N08825 nickel-iron-chromium-molybdenum-copper alloy rod and bar.
Is Alloy 825 suitable for sulfuric acid?
It is widely considered for many sulfuric-acid conditions, but concentration, temperature, velocity, contaminants and aeration determine actual suitability.
How does Alloy 825 compare with C276?
C276 generally targets more severe and broader chemical corrosion, while Alloy 825 can offer a cost-effective solution in compatible acid and process environments.
Can Alloy 825 threaded rod be supplied in metric sizes?
Yes. Metric threads can be produced to the ordered ISO or ASME metric standard, tolerance and length, subject to material availability.
Related threaded rod products
Request a technical quotation
Send your bill of materials, drawing or project specification. SASA FLANGE will review the grade, thread, dimensions, documentation and delivery requirements before quotation.
