AISI 8625 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 8625 Steel Flange Product Information -:- For detailed product information, please contact sales. -: AISI 8625 Steel Flange Synonyms -:- For detailed product information, please contact sales. -:

AISI 8625 Steel Product Information -:- For detailed product information, please contact sales. -: ### **Product Introduction: AISI 8625 Steel** #### **1. Overview** AISI 8625 is a versatile **low-carbon nickel-chromium-molybdenum (Ni-Cr-Mo) alloy steel**, classified within the American Iron and Steel Institute (AISI) 8600 series as a **case-hardening (carburizing) grade**. With a balanced composition centered around **higher carbon content** than the more common AISI 8620, this steel is engineered to deliver **superior core strength and hardenability** while maintaining excellent toughness. After carburizing heat treatment, it develops the characteristic **"hard case, tough core"** microstructure, making it particularly suitable for **medium to heavy-duty components** that require enhanced load-bearing capacity beneath the wear-resistant surface. #### **2. International Standards & Designations** AISI 8625 is recognized under multiple international standards with equivalent designations across different regional systems. | Region/System | Standard Designation | Title / Purpose | | :--- | :--- | :--- | | **USA (AISI/SAE)** | **AISI 8625, SAE J404** | Standard Chemical Composition | | **USA (ASTM)** | **ASTM A322** | Standard Specification for Steel Bars, Alloy, Standard Grades | | **USA (ASTM)** | **ASTM A534** | Carburizing Steels for Anti-Friction Bearings | | **UNS Number** | **G86250** | Unified Numbering System | | **Europe (EN)** | **1.6526 / 25NiCrMo2-2** | Equivalent Material Standard | | **Germany (DIN/W-Nr.)** | **25NiCrMo2 / 1.6526** | Equivalent Designation | | **Japan (JIS)** | **SNCM420** (Close Equivalent) | Similar Material Standard | | **International** | **ISO 683-11: 25NiCrMo2-2** | International Material Standard | #### **3. Chemical Composition** The alloy composition is optimized for good hardenability and core strength, with carbon content being the primary differentiator from lower-numbered grades in the 8600 series. | Element | Content (% by Weight) | Metallurgical Role | | :--- | :--- | :--- | | **Carbon (C)** | **0.23 - 0.28** | **Key feature:** Provides higher core strength and hardenability compared to 8620/8622. Forms the basis for martensitic transformation. | | **Manganese (Mn)** | 0.70 - 0.90 | Enhances hardenability, aids in deoxidation, and strengthens the ferrite matrix. | | **Phosphorus (P)** | ≤ 0.035 | Residual impurity; controlled to minimize cold brittleness. | | **Sulfur (S)** | ≤ 0.040 | Residual impurity; improves machinability but controlled to prevent hot shortness. | | **Silicon (Si)** | 0.15 - 0.35 | Powerful deoxidizer; provides solid solution strengthening. | | **Nickel (Ni)** | 0.40 - 0.70 | **Critical element:** Significantly enhances core toughness and hardenability while lowering ductile-to-brittle transition temperature. | | **Chromium (Cr)** | 0.40 - 0.60 | Increases hardenability depth; promotes formation of hard carbides in the case during carburizing. | | **Molybdenum (Mo)** | 0.15 - 0.25 | Enhances hardenability; reduces susceptibility to temper embrittlement; improves high-temperature strength. | | **Iron (Fe)** | Balance | Base metal. | #### **4. Mechanical & Physical Properties** *Properties vary significantly with condition (annealed, normalized, heat-treated). The following represents typical characteristics.* **Typical Properties in Annealed Condition (Machining Stock):** * **Hardness:** **156 - 207 HB** (Brinell) * **Ultimate Tensile Strength:** **540 - 690 MPa** (78 - 100 ksi) * **Yield Strength:** **400 - 550 MPa** (58 - 80 ksi) * **Elongation:** **20% - 26%** * **Reduction of Area:** **50% - 60%** * **Machinability:** **~60%** of B1112 steel (Good with proper tooling). **Properties After Case Hardening (Carburized & Hardened):** * **Surface Case Hardness:** **58 - 63 HRC** (Rockwell C) * **Effective Case Depth:** Typically 0.5 - 2.0 mm (0.020" - 0.080"), adjustable per process. * **Core Hardness:** **38 - 50 HRC** (Higher than 8620/8622 due to increased carbon content). * **Core Tensile Strength:** **1200 - 1500 MPa** (174 - 218 ksi) * **Core Yield Strength:** **1000 - 1300 MPa** (145 - 189 ksi) * **Impact Toughness:** Good, maintained by nickel content despite higher strength. **Physical Properties:** * **Density:** **7.85 g/cm³** (0.284 lb/in³) * **Modulus of Elasticity:** **205 GPa** (29,700 ksi) * **Poisson's Ratio:** **0.29** * **Thermal Conductivity:** **~44 W/m·K** at 100°C * **Coefficient of Thermal Expansion:** **12.4 × 10⁻⁶/°C** (20-100°C) #### **5. Product Applications** AISI 8625 is employed in applications requiring a robust combination of surface wear resistance and high core strength, particularly where components are subjected to significant bending or torsional stresses. * **Heavy-Duty Gearing:** Medium to large gears for industrial transmissions, mining equipment, agricultural machinery, and heavy vehicle differentials. * **High-Load Bearing Components:** Bearing races and rollers subjected to substantial contact stresses. * **Automotive & Truck Components:** Critical transmission gears, camshafts, and axle shafts in medium to heavy-duty vehicles. * **Oil & Gas Equipment:** Downhole tool components, valve parts, and pump gears requiring durability under high pressure. * **Construction & Mining Machinery:** Pins, bushings, shafts, and final drive components. * **Power Transmission Systems:** Couplings, splined shafts, and sprockets for conveyor systems. #### **6. Key Characteristics & Advantages** * **Enhanced Core Strength & Hardenability:** The higher carbon content (0.23-0.28%) provides significantly greater core strength and hardenability than 8620, enabling use in larger sections or higher-stress applications. * **Excellent Toughness Retention:** Despite higher strength, the nickel content ensures good impact resistance and fracture toughness in the core. * **Superior Load-Bearing Capacity:** The strong core provides excellent support for the hardened case, making it ideal for components experiencing high bending or contact fatigue loads. * **Good Wear & Pitting Resistance:** The carburized case provides excellent surface durability against abrasion and contact fatigue (pitting). * **Good Machinability (Pre-HT):** In the annealed or normalized condition, it can be readily machined into complex shapes. * **Weldability:** Fair with proper procedures (preheat and post-weld heat treatment recommended). * **Versatile Heat Treatment Response:** Responds well to various carburizing methods (gas, liquid, plasma) and quenching techniques. **Conclusion:** **AISI 8625 is a robust and reliable medium-carbon case-hardening steel that occupies an important position between the more common 8620 and the higher-carbon 8630 grades.** Its balanced composition delivers an optimal combination of **surface hardness, core strength, and retained toughness**, making it a preferred choice for engineering components that must withstand both severe surface wear and significant subsurface stresses. The steel's predictable response to carburizing heat treatment and its ability to maintain good toughness at higher strength levels make it a trusted material for demanding applications in heavy machinery, transportation, and industrial equipment sectors. When component designs require greater load capacity than 8620 can provide but the exceptional toughness of nickel-alloyed steel must be maintained, AISI 8625 presents an excellent technical and economic solution. -:- For detailed product information, please contact sales. -: AISI 8625 Steel Specification Dimensions Size： Diameter 20-1000 mm Length <5743 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 8625 Steel Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 8625 Steel Flange -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 8625 Steel Flange -:- For detailed product information, please contact sales. -:

Packing of AISI 8625 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 2214 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