Project Description
AISI 8630 / 8630 mod Alloy Steel Supplier
AISI 8630 and its modified version (8630 mod / 1.6591) are premium low-alloy nickel-chromium-molybdenum steels engineered for exceptional toughness, high strength, and deep hardenability. The precisely balanced carbon, nickel, chromium, and molybdenum content ensures outstanding wear resistance and low-temperature impact toughness. As a premier manufacturer certified to API Q1 and ISO 9001, ShunFu Metal specializes in supplying this critical grade to the global oil, gas, and mining sectors.
With extensive experience exporting to over 50 countries and serving the world's top 10 oilfield service companies, our factory delivers AISI 8630 materials that meet the most demanding subsea and wellhead specifications.
Critical Applications
AISI 8630 / 8630 mod is specifically designed for applications requiring high strength and toughness in large section sizes. Typical applications include:
- Wellhead Components & Subsea Connectors (Oil & Gas): Supplied by ShunFu Metal as heavy-section forged blocks and round bars, fully quenched and tempered in our API-calibrated furnaces to meet NACE MR0175 sour service requirements for critical casing and tubing programs.
- Drill Collar Blanks & Downhole Tools (Drilling): Manufactured using our in-house BTA deep hole drilling and CNC machining capabilities, delivered as precision-machined hollow bars for high-performance drill collars with guaranteed straightness and internal bore integrity.
- Valve Body Forgings & High-Pressure Manifolds (Oil & Gas): Provided as custom closed-die or open-die forgings. Our high forging ratios ensure the fine grain structure essential for high-pressure fluid control applications.
- Heavy-Duty Pinions & Drive Shafts (Mining): Supplied as turned and polished round bars, utilizing our in-house rough machining and ultrasonic testing to guarantee internal soundness for high-torque mining equipment.
Technical Specifications & Standards
AISI 8630 / 8630 mod complies with the following international standards and specifications. ShunFu Metal strictly organizes our production processes in accordance with these requirements, providing comprehensive Material Test Reports (MTRs) with every delivery.
- ASTM A29/A29M – Standard Specification for Steel Bars, Carbon and Alloy, Hot-Wrought
- ASTM A473 – Standard Specification for Stainless Steel Forgings
- ASTM A508/A508M Grade 4A – Standard Specification for Quenched and Tempered Vacuum-Treated Carbon and Alloy Steel Forgings for Pressure Vessels
- ASTM A519 – Standard Specification for Seamless Carbon and Alloy Steel Mechanical Tubing
- ASTM A646 – Standard Specification for Premium Quality Alloy Steel Blooms and Billets for Aircraft and Aerospace Forgings
- SAE J1268 – Standard for 86xx Series Alloy Steels
- API 6A – Specification for Wellhead and Tree Equipment
- API 16A – Specification for Drill-through Equipment
- NACE MR0175/ISO 15156 – Materials for use in H₂S-containing Environments in Oil and Gas Production
Available Sizes & Global Delivery
ShunFu Metal offers highly flexible sizing for AISI 8630, including forged and rolled round bars (25mm–500mm), heavy forged blocks (up to 1000mm thick), plates, and custom pre-drilled precision hollow bars. Our facility features high-ratio forging presses, API-compliant calibrated heat treatment furnaces, and precision machining equipment.
- Ready Stock: Standard sizes available from inventory with a minimum order of 1 piece and a rapid 7-day delivery.
- Custom Forgings/Rolled Bars: Minimum order quantity (MOQ) is typically 3 tons, with a lead time of approximately 30 days.
- Small Batch Special Melts: Our specialized induction furnaces accommodate custom chemistry runs starting from 3–5 tons.
- Large Volume Orders: Processed via our 30–60 ton EAF route for fast, high-capacity fulfillment.
Chemical Composition
ShunFu Metal strictly controls the chemical composition of AISI 8630 through rigorous in-house spectrometry during the melt shop process. We verify every single heat to ensure all element levels comply perfectly with standard specifications.
| Element | C | Si | Mn | P | S | Cr | Mo | Ni | V | Cu |
|---|---|---|---|---|---|---|---|---|---|---|
| Min (%) | 0.28 | 0.15 | 0.75 | - | - | 0.85 | 0.35 | - | - | - |
| Max (%) | 0.33 | 0.45 | 1.00 | ≤ 0.025 | ≤ 0.025 | 1.50 | 0.65 | 1.00 | ≤ 0.06 | ≤ 0.25 |
Mechanical Properties (Quenched & Tempered)
The following data represents the typical mechanical properties of AISI 8630 / 8630 mod in the Quenched and Tempered (QT) condition. Prior to dispatch, ShunFu Metal issues comprehensive test reports from our accredited laboratory, with data 100% traceable to the specific heat batch.
| 0.2%-Offset-Yield Strength Rp0.2 | ≥ 517 MPa (75 ksi) |
|---|---|
| Tensile Strength Rm | ≥ 655 MPa (95 ksi) |
| Elongation L0 = 4 d (A5) | ≥ 18% |
| Reduction of Area (Z) | ≥ 35% |
| Impact Toughness (Charpy-V at 23 °C) | ≥ 54 J (40 ft-lbs) |
| Impact Toughness (Charpy-V at -60 °C) | ≥ 27 J (20 ft-lbs) |
| Hardness | 207 – 234 BHN (19 – 22 HRC) |
Heat Treatment Regime
ShunFu Metal executes all thermal processing in our proprietary heat treatment facility. Our furnaces are strictly calibrated in full compliance with API standards, guaranteeing exceptional temperature uniformity and process repeatability.
| Process | Temperature Range | Cooling Method |
|---|---|---|
| Normalizing | 870-925°C (1600-1700°F) | Air cooling |
| Austenitizing | 830-870°C (1525-1600°F) | Oil or water quenching |
| Tempering | 540-675°C (1000-1250°F) | Air cooling |
| Stress Relieving | 550-650°C (1020-1200°F) | 1 hour per 25 mm of thickness |
Quality Assurance & Inspection
ShunFu Metal’s quality control for AISI 8630 is anchored by our API Q1 and ISO 9001 certifications, ensuring zero-defect material integrity for critical oilfield applications. Our rigorous inspection protocols include 100% Ultrasonic Testing (UT), dimensional verification, and in-depth metallographic examination.
We specifically perform four-quadrant hardness testing on heavy cross-sections to verify uniform through-hardenability. Every order is supplied with an EN 10204 3.1 material certificate, while 3.2 certification is available upon request. We seamlessly coordinate with third-party agencies like SGS and TÜV to validate our stringent standards.
Frequently Asked Questions About AISI 8630 Alloy Steel
Can ShunFu Metal supply AISI 8630 mod to API 6A and NACE MR0175 specifications?
Yes. ShunFu Metal holds API Q1 certification and specifically engineers our 8630 mod melting and heat treatment processes to meet the stringent hydrogen sulfide (H₂S) resistance requirements of NACE MR0175/ISO 15156 for sour service wellhead equipment.
What is the minimum order quantity for custom AISI 8630 hollow bars?
For custom-machined AISI 8630 hollow bars utilizing our in-house BTA boring and CNC equipment, the typical MOQ is 3 tons with a 30-day lead time. However, we also maintain ready stock of standard solid round bars that can be ordered from just 1 piece.
How does ShunFu Metal ensure consistent hardness in large AISI 8630 forged blocks?
We utilize high-ratio forging presses followed by processing in our API-calibrated heat treatment furnaces. To guarantee through-hardenability, our quality assurance team conducts mandatory four-quadrant hardness testing and ultrasonic inspection on all heavy-section blocks before shipment.
What melting routes are available for ultra-critical AISI 8630 applications?
ShunFu Metal offers customizable melting routes. Our standard production utilizes EAF + LF + VD for excellent purity. For stricter requirements, we provide ESR or PESR refining. For ultra-critical applications, VIM + VAR melting is available to ensure the highest levels of cleanliness and microstructure refinement.