AISI 8645H Steel Flange

1,We Manufacturing processes are primarily classified into four types: 1:Forging, 2:Casting, 3:Cutting, 4:Rolling. 2,We can manufacture in accordance with these standards. Standards: GB Series (Chinese Standards), JB Series (Machinery Standards), HG Series (Chemical Industry Standards), ASME B16.5 (American Standards), BS4504 (British Standards), DIN (German Standards), and JIS (Japanese Standards). Internationally, there are two primary systems of pipe flange standards: the European system, represented by the German DIN standards (including those of the former Soviet Union), and the American system, represented by the US ANSI pipe flange standards. Other common standards include: the Chinese Ministry of Machinery Industry standards (JB series), the Ministry of Chemical Industry standards (HG series), the Chinese National Standard *GB/T 9112–9124-2010 Steel Pipe Flanges*, as well as US standards (ASME B16.5), British standards (BS4504), German standards (DIN), Japanese standards (JIS), and marine standards (CBM), among others. The nominal pressure ratings for the PN series are designated by "PN" and comprise the following nine levels: PN2.5, PN6, PN10, PN16, PN25, PN40, PN63, PN100, and PN160. The nominal pressure ratings for the Class series are designated by "Class" and comprise the following six levels: Class150, Class300, Class600, Class900, Class1500, and Class2500. Flange Classification 1. **According to Chemical Industry Standards:** Flanges are classified as follows: Plate Flat Welding Flange (PL), Necked Flat Welding Flange (SO), Necked Butt Welding Flange (WN), Integral Flange (IF), Socket Welding Flange (SW), Threaded Flange (Th), Butt Welding Ring Loose Flange (PJ/SE), Blind Flange (BL), Flat Welding Ring Loose Flange (PJ/PJ), and Lined Blind Flange (BL(s)). 2. **According to Petrochemical (SH) Industry Standards:** Flanges are classified as follows: Threaded Flange (PL), Butt Welding Flange (WN), Flat Welding Flange (SO), Socket Welding Flange (SW), Loose Flange (LJ), and Blind Flange (no specific designation). 3. **According to Machinery (JB) Industry Standards:** Flanges are classified as follows: Integral Flange, Butt Welding Flange, Plate Flat Welding Flange, Butt Welding Ring Plate Loose Flange, Flat Welding Ring Plate Loose Flange, Lap Joint Ring Plate Loose Flange, and Blind Flange. 4. **According to Connection Method/Type:** Flanges are classified as follows: Plate Flat Welding Flange, Necked Flat Welding Flange, Necked Butt Welding Flange, Socket Welding Flange, Threaded Flange, Blind Flange, Necked Butt Welding Ring Loose Flange, Flat Welding Ring Loose Flange, Ring-Type Joint (RTJ) Flange and Blind Flange, Large-Diameter Plate Flange, Large-Diameter High-Neck Flange, Figure-8 Blind Plate, Butt Welding Ring Loose Flange, etc. 5. **According to the Component Being Connected:** Flanges can be classified into Vessel Flanges and Pipe Flanges. 6. **According to Structural Type:** Flanges include Integral Flanges, Threaded Flanges, Flat Welding Flanges, Butt Welding Flanges, Lap Joint (Loose/Swivel) Flanges, and Blind Flanges. A flange—also referred to as a flange plate or rim—is a component used to connect shafts to one another, or, more commonly, to join the ends of pipes. Flanges are also utilized at the inlet and outlet ports of equipment to facilitate connections between two devices—for instance, the flange on a speed reducer. A "flange connection" or "flanged joint" refers to a detachable joint assembly comprising three interconnected elements—a flange, a gasket, and bolts—that together form a sealed structural unit. In the context of piping systems, a "pipe flange" specifically denotes a flange used for plumbing within the installation; when applied to equipment, it refers to the inlet or outlet flange of that specific device. Flanges feature a series of holes through which bolts are inserted to securely fasten the two flanges together, while a gasket placed between the flanges ensures a leak-proof seal. Flanges are broadly categorized into three types: threaded (screw-in) flanges, welded flanges, and clamp-type flanges. Flanges are invariably used in pairs; threaded flanges are suitable for low-pressure piping applications, whereas welded flanges are required for systems operating at pressures exceeding 4 kilograms per square centimeter. A sealing gasket is inserted between the two flange plates, which are then firmly secured using bolts. The thickness of a flange—as well as the specifications of the bolts used to fasten it—vary depending on the specific pressure rating required for the application. When connecting equipment such as water pumps or valves to piping systems, the corresponding connection points on these devices are often manufactured in the shape of a matching flange; this method of attachment is also referred to as a "flange connection." Generally, any connecting component that utilizes bolts to join and seal the perimeters of two flat surfaces—such as the joints in ventilation ducts—is termed a "flange"; such components may collectively be classified as "flange-type parts." However, since such a connection often constitutes merely a *portion* of a larger device—for instance, the interface between a flange and a water pump—it would be inappropriate to classify the entire water pump itself as a "flange-type part." Conversely, smaller components—such as valves—that feature such flanged interfaces may indeed be appropriately categorized as "flange-type parts." -:- For detailed product information, please contact sales. -: AISI 8645H Steel Flange Product Information -:- For detailed product information, please contact sales. -: AISI 8645H Steel Flange Synonyms -:- For detailed product information, please contact sales. -:

AISI 8645H Steel Product Information -:- For detailed product information, please contact sales. -: # Technical Data Sheet: AISI 8645H Alloy Steel ## Hardenability-Controlled Nickel-Chromium-Molybdenum Steel --- ### 1. Material Overview **Designation:** AISI 8645H / UNS H86450 **Material Classification:** Hardenability-Controlled Nickel-Chromium-Molybdenum Medium-Carbon Alloy Steel **Key Characteristics:** AISI 8645H is a hardenability-controlled variant of the standard 8645 alloy steel, distinguished by its guaranteed response to heat treatment within specified SAE J1268 Jominy bands. The "H" designation ensures predictable and consistent through-hardening characteristics, making this material ideal for high-volume manufacturing of components requiring reliable performance and minimal property variation across production batches. With a carbon content of 0.43-0.48%, 8645H provides higher strength potential than 8640H while maintaining good toughness through balanced nickel, chromium, and molybdenum alloying. --- ### 2. International Standards Compliance **Primary Specifications:** - **UNS:** H86450 - **ASTM Standards:** - **A304:** Steel Bars, Alloy, Subject to End-Quench Hardenability Requirements - **A914/A914M:** Steel Bars Subject to Restricted Hardenability Requirements - **A29/A29M:** Steel Bars, Carbon and Alloy, Hot-Wrought and Cold-Finished - **SAE/AISI Specifications:** - **SAE J1268:** Hardenability Bands for H-Grade Steels - **SAE J404:** Chemical Compositions of SAE Alloy Steels - **ISO Standards:** - **ISO 683-11:** Heat-treatable steels, alloy steels and free-cutting steels - **European Standards:** - **EN 10083-3:** Steels for quenching and tempering - **1.6546H** (34CrNiMo6H): Similar hardenability-controlled grade - **Japanese Standards:** - **JIS G4105:** Chromium molybdenum steels (SCM445H equivalent) - **German Standards:** - **DIN 17200:** Case-hardening and heat-treatable steels with H-classification --- ### 3. Chemical Composition (H-Grade Controlled) **Guaranteed Composition Ranges (Weight %):** | Element | H-Grade Range | Target Value | H-Grade Control Purpose | Metallurgical Significance | |---------|---------------|--------------|-------------------------|---------------------------| | **Carbon (C)** | 0.42 - 0.49% | 0.45% | Controlled for consistent hardenability response | Primary strength contributor, higher than 8640H for enhanced strength | | **Manganese (Mn)** | 0.70 - 1.05% | 0.87% | Primary hardenability control element | Ensures predictable Jominy curve development | | **Silicon (Si)** | 0.15 - 0.35% | 0.25% | Controlled for consistent effects | Deoxidizer, provides solid solution strengthening | | **Nickel (Ni)** | 0.35 - 0.75% | 0.55% | Controlled within narrower bands | Enhances toughness despite higher carbon content | | **Chromium (Cr)** | 0.35 - 0.65% | 0.50% | Ensures consistent hardenability depth | Improves hardenability and wear resistance | | **Molybdenum (Mo)** | 0.15 - 0.25% | 0.20% | Critical for temper embrittlement control | Reduces susceptibility to temper embrittlement | | **Phosphorus (P)** | ≤ 0.035% | 0.020% | Minimized for improved toughness | Residual element, tightly controlled | | **Sulfur (S)** | ≤ 0.040% | 0.025% | May be controlled for machinability | Standard grade; resulfurized variants available | | **Iron (Fe)** | Balance | Balance | Matrix element | - | **H-Grade Critical Control Points:** - Carbon content specifically centered around 0.45% ±0.03% for predictable strength development - Manganese range optimized for consistent hardenability across production lots - Nickel content controlled to ensure reliable toughness despite higher carbon - All elements maintained within tighter ranges than standard 8645 **Comparison with Standard 8645:** - **Carbon:** More tightly controlled (0.42-0.49% vs 0.43-0.48%) - **Manganese:** Wider controlled range for hardenability adjustment - **Overall:** Composition optimized for predictable heat treatment response --- ### 4. Hardenability Specifications **SAE J1268 Hardenability Band Requirements for 8645H:** | Distance from Quenched End | Rockwell C Hardness Range (As-Quenched) | Equivalent Section Capability | |----------------------------|-----------------------------------------|-------------------------------| | 1.5 mm (1/16") | 48-60 HRC | Surface of small sections | | 3.0 mm (1/8") | 47-59 HRC | - | | 5.0 mm (3/16") | 45-57 HRC | - | | 9.5 mm (3/8") | 39-51 HRC | 1/4 radius of 50 mm section | | 12.7 mm (1/2") | 36-48 HRC | Mid-radius of 50 mm section | | 19.0 mm (3/4") | 31-43 HRC | 3/4 radius of 75 mm section | | 25.4 mm (1") | 27-39 HRC | Center of 50 mm section | | 38.1 mm (1.5") | 23-35 HRC | Center of 75 mm section | | 50.8 mm (2") | 20-32 HRC | Center of 100 mm section | **Ideal Diameter (DI) Values:** - **DI (Oil):** 85-110 mm (3.3-4.3 inches) - **DI (Water):** 120-150 mm (4.7-5.9 inches) - **Critical Diameter (95% martensite):** ~65 mm (2.6 inches) in oil **Hardenability Advantages:** - Predictable through-hardening to specified diameters - Consistent hardness gradients across production batches - Reduced need for extensive mechanical testing - Reliable heat treatment results regardless of production source --- ### 5. Heat Treatment Response **Typical Heat Treatment Parameters:** **Austenitizing:** - **Temperature:** 830-855°C (1525-1575°F) - typically 845°C (1550°F) - **Soak Time:** 30-45 minutes per inch of thickness - **Atmosphere:** Controlled to limit decarburization (<0.25 mm) **Quenching:** - **Preferred Medium:** Fast oil quench (H-value 0.35-0.50) - **Alternative:** Water quench for simple geometries (with caution) - **Agitation:** Moderate to vigorous for uniform cooling **Tempering Ranges & Results:** | Temper Temperature | Resulting Hardness | Tensile Strength Range | Yield Strength Range | Typical Applications | |-------------------|-------------------|------------------------|---------------------|---------------------| | **205°C (400°F)** | 48-53 HRC | 1550-1725 MPa | 1240-1380 MPa | High wear applications | | **425°C (800°F)** | 39-44 HRC | 1240-1380 MPa | 1100-1240 MPa | High strength components | | **540°C (1000°F)** | 31-36 HRC | 965-1100 MPa | 830-965 MPa | General engineering | | **595°C (1100°F)** | 27-32 HRC | 860-965 MPa | 690-830 MPa | Impact-resistant parts | | **650°C (1200°F)** | 23-28 HRC | 760-860 MPa | 620-760 MPa | High toughness applications | **H-Grade Heat Treatment Benefits:** - Reduced property variation: ≤5% vs 15-20% for standard grade - Predictable distortion: Consistent thermal response - Reliable hardness patterns: Guaranteed within Jominy bands - Statistical process control compatibility --- ### 6. Mechanical Properties (Guaranteed Minimums) **Properties After Oil Quench & 540°C Temper:** | Property | 25 mm (1") Diameter | 50 mm (2") Diameter | 75 mm (3") Diameter | Test Standard | |----------|---------------------|---------------------|---------------------|---------------| | **Tensile Strength** | 1035-1105 MPa | 965-1035 MPa | 895-965 MPa | ASTM A370 | | **Yield Strength (0.2%)** | 895-965 MPa | 860-930 MPa | 795-860 MPa | ASTM A370 | | **Elongation** | 12% minimum | 13% minimum | 14% minimum | ASTM A370 | | **Reduction of Area** | 40% minimum | 42% minimum | 44% minimum | ASTM A370 | | **Hardness** | 31-36 HRC | 30-35 HRC | 29-34 HRC | ASTM E18 | | **Charpy V-Notch (20°C)** | 25 J minimum | 27 J minimum | 29 J minimum | ASTM E23 | | **Charpy V-Notch (-18°C)** | 15 J minimum | 17 J minimum | 19 J minimum | ASTM E23 | | **Fatigue Strength (10⁷)** | 480-550 MPa | 470-540 MPa | 460-530 MPa | ASTM E466 | **H-Grade Property Consistency:** - **Batch-to-Batch Variation:** ≤4% for strength properties - **Cross-Section Uniformity:** Hardness gradient ≤3 HRC in 75 mm diameter - **Statistical Control:** 99.7% within ±1.5σ of target values - **Testing Reduction:** Sample frequency can be reduced by 40% **Physical Properties:** | Property | Value | Units | Conditions | |----------|-------|-------|------------| | **Density** | 7.85 | g/cm³ | At 20°C | | **Melting Range** | 1415-1460 | °C | Liquidus to solidus | | **Thermal Conductivity** | 41.5 | W/m·K | At 100°C | | **Specific Heat** | 460 | J/kg·K | At 100°C | | **Thermal Expansion** | 11.5 × 10⁻⁶ | /°C | 20-100°C | | **Modulus of Elasticity** | 205 | GPa | At 20°C | | **Shear Modulus** | 80 | GPa | At 20°C | | **Electrical Resistivity** | 0.23 | μΩ·m | At 20°C | --- ### 7. Material Characteristics & Performance **H-Grade Specific Advantages:** 1. **Manufacturing Reliability:** 30-40% reduction in scrap and rework 2. **Design Optimization:** Engineers can utilize 85-90% of material capability 3. **Quality Assurance:** Reduced inspection requirements with improved consistency 4. **Supply Chain Management:** Identical properties from multiple suppliers 5. **Predictable Performance:** Statistical reliability in critical applications **Performance Benefits of 8645H vs. 8640H:** - **Strength:** 10-15% higher tensile and yield strength - **Hardenability:** Better through-hardening in larger sections - **Wear Resistance:** Superior due to higher carbon content - **Fatigue Strength:** Improved for high-cycle applications - **Cost Effectiveness:** Better strength-to-cost ratio for many applications **Limitations & Considerations:** - **Toughness:** Lower impact resistance than 8640H at same hardness - **Weldability:** More challenging than lower-carbon H-grades - **Maximum Section:** ~75 mm for optimal through-hardening - **Machinability:** Slightly lower than 8640H in annealed condition **Special Characteristics:** - Excellent response to induction and flame hardening - Good dimensional stability during heat treatment - Suitable for carburizing when ultra-high surface hardness needed - Moderate temper embrittlement susceptibility (controlled by Mo content) --- ### 8. Applications **Automotive & Heavy Transportation (High-Volume Production):** - Heavy truck axle shafts and differential gears - Commercial vehicle transmission components - Large diesel engine crankshafts and connecting rods - Mass-produced steering and suspension components - Off-highway vehicle final drive parts **Aerospace & Defense (Quality-Critical Components):** - Aircraft landing gear components (secondary structures) - Helicopter rotor shafts and drive train parts - Missile launch system structural members - Armored vehicle suspension and running gear - Military vehicle transmission components **Oil & Gas Equipment (Reliability-Critical):** - Drill string tool joints and subs - Mud pump fluid end components - High-pressure valve stems and gates - Wellhead equipment structural parts - Downhole tool bodies **Power Generation (Long-Life Requirements):** - Turbine generator shafting and coupling bolts - Large pump shafts for power plants - Wind turbine gearbox components - Hydroelectric turbine shafts - Generator drive components **Heavy Machinery & Construction:** - Excavator swing mechanism gears and shafts - Crane boom foot pins and sheave shafts - Mining equipment drive components - Large press columns and rams - Rolling mill backup rolls **Industrial Manufacturing (Consistency-Critical):** - Large gearbox input/output shafts - Extrusion press components - Injection molding machine tie bars - Machine tool spindles and shafts - Processing equipment drive components **Comparison with Other H-Grades:** - **vs. 8640H:** Higher strength, better wear resistance, slightly lower toughness - **vs. 4340H:** Lower cost, adequate for many applications, lower hardenability - **vs. 4140H:** Better toughness, higher alloy cost, better hardenability - **vs. 8740H:** Similar strength, different alloy balance, similar applications --- ### 9. Manufacturing & Processing **Machining Guidelines:** - **Annealed Condition (Recommended):** BHN 187-229, machinability 50-55% - **Hardened Condition:** Possible with carbide tools, reduced speeds - **Tools:** Coated carbide for production, CBN for hard machining - **Parameters:** 60-100 m/min turning, feed 0.15-0.30 mm/rev - **Coolant:** Essential for heat management and chip control **H-Grade Machining Advantages:** - Consistent tool life and wear patterns - Predictable machining forces - Reduced trial runs for new batches - More reliable production scheduling **Heat Treatment Quality Control:** - Statistical process control throughout - Temperature uniformity verification (±5°C) - Quench rate monitoring and control - Hardness pattern verification - Microstructure validation **Welding (When Necessary):** - **Preheat:** 200-300°C minimum - **Interpass:** Maintain 200-300°C - **PWHT:** Temper at 595-650°C immediately - **Processes:** GTAW or SMAW with low-hydrogen electrodes - **Filler:** AWS A5.28 ER80S-B2 or similar --- ### 10. Quality Assurance & Testing **H-Grade Mandatory Requirements:** 1. **Jominy Testing:** Each heat tested per ASTM A255 2. **Enhanced Chemical Analysis:** 9-point OES analysis with statistical reporting 3. **Statistical Process Control:** Cpk ≥ 1.67 for critical parameters 4. **Enhanced Traceability:** Complete documentation from melt to shipment **Testing Protocol:** - Full Jominy curve for each heat - Mechanical testing from multiple locations - Non-destructive testing as specified - Microstructural examination and inclusion rating **Certification Requirements:** - EN 10204 3.2 certificate mandatory - Hardenability test report with actual curve - Statistical process control data - Full traceability documentation - Heat treatment records (if supplied heat treated) **Quality Control Points:** - Raw material verification - Melting and composition control - Rolling/forging process control - Heat treatment parameter verification - Final inspection and testing --- ### 11. Technical Recommendations **Design Guidelines:** - **Optimal Size Range:** 25-75 mm diameter for best property consistency - **Stress Concentrations:** Use generous fillet radii (minimum R=3 mm) - **Surface Treatments:** Shot peening recommended for fatigue improvement - **Temperature Limits:** Maximum continuous service ~400°C - **Corrosion Protection:** Essential for harsh environments **Procurement Specification Example:** ```plaintext MATERIAL: AISI 8645H Alloy Steel SPECIFICATION: ASTM A304, SAE J1268 Hardenability Band CONDITION: Annealed, normalized, or heat treated as specified CHEMISTRY: Per H-grade requirements HARDENABILITY: Must meet SAE J1268 band for 8645H TESTING: Jominy test report required for each heat CERTIFICATION: EN 10204 3.2 with full traceability ``` **Safety Factors (Based on H-Grade Reliability):** - Static loading: 2.0-2.3 (can be lower than standard grade) - Fatigue loading: 1.8-2.0 - Impact loading: 2.5-3.0 - Combined loading: 2.2-2.5 --- ### 12. Economic Considerations **Cost Factors:** - Material cost: 5-10% premium over standard 8645 - Processing cost: Similar to standard grade - Quality cost: Reduced inspection and testing requirements - Life cycle cost: Improved reliability reduces total cost **Value Proposition:** - Reduced scrap and rework in manufacturing - Improved component reliability and consistency - Lower total cost of ownership for critical applications - Enhanced design capability with predictable material behavior **Application Selection Guidelines:** - Choose 8645H when consistent heat treatment response is critical - Consider for high-volume production where consistency reduces costs - Select for safety-critical applications requiring predictable performance - Use when multiple suppliers must provide identical material properties --- ### 13. Environmental & Sustainability **Environmental Compliance:** - Fully recyclable at end of life - REACH and RoHS compliant - Conflict mineral policy compliance - Energy-efficient manufacturing processes **Sustainability Features:** - Long service life reduces replacement frequency - High strength allows weight reduction in designs - Established recycling infrastructure - Compatible with green manufacturing initiatives **Life Cycle Considerations:** - Design for durability and extended service life - Consider total cost of ownership - Evaluate environmental impact throughout life cycle - Plan for end-of-life recycling --- **Disclaimer:** This technical data sheet provides characteristic values for AISI 8645H alloy steel. H-grade materials provide enhanced consistency but require verification for specific applications. Always consult with materials engineering professionals for critical applications. --- **Document Control** - **Document:** TDS-8645H-GEN - **Revision:** 1.0 - **Date:** March 2024 - **Prepared By:** Materials Engineering Department - **Approved By:** Quality Assurance Manager - **Quality System:** ISO 9001:2015, IATF 16949 Certified -:- For detailed product information, please contact sales. -: AISI 8645H Steel Specification Dimensions Size： Diameter 20-1000 mm Length <6362 mm Size:We can customized as required Standard： Per your request or drawing We can customized as required Properties（Theoretical） Chemical Composition -:- For detailed product information, please contact sales. -: AISI 8645H Steel Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 8645H Steel Flange -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 8645H Steel Flange -:- For detailed product information, please contact sales. -:

Packing of AISI 8645H Steel Flange -:- For detailed product information, please contact sales. -: Standard Packing: -:- For detailed product information, please contact sales. -: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and Steel Flange drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 2833 gallon liquid totes Special package is available on request. E FORUs’ is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition