AISI 8637 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 8637 Steel Flange Product Information -:- For detailed product information, please contact sales. -: AISI 8637 Steel Flange Synonyms -:- For detailed product information, please contact sales. -:

AISI 8637 Steel Product Information -:- For detailed product information, please contact sales. -: ## **Product Introduction: AISI 8637 Steel** **AISI 8637** is a versatile **nickel-chromium-molybdenum (Ni-Cr-Mo) low-alloy steel** belonging to the 8600 series, known for its excellent combination of **strength, toughness, and hardenability**. This grade is characterized by a medium carbon content that provides a robust balance between surface hardness potential and core toughness, making it particularly suitable for components that require **through-hardening** or **case hardening** (via carburizing). 8637 offers reliable performance at a moderate cost and is a staple material in demanding automotive, aerospace, and heavy machinery applications where dynamic loads and fatigue resistance are critical. --- ### **1. Chemical Composition (Typical Weight %, AISI/SAE Standard)** The composition is designed to provide good deep-hardening characteristics and a strong, tough core. | Element | Content Range | Primary Metallurgical Function | | :--- | :--- | :--- | | **Carbon (C)** | 0.35 – 0.40 | Provides base hardenability and strength. Optimized for a balance of core strength and case hardenability. | | **Manganese (Mn)** | 0.75 – 1.00 | Enhances hardenability and strength. Aids in deoxidation during steelmaking. | | **Phosphorus (P)** | ≤ 0.035 | Residual impurity; kept low to preserve toughness and formability. | | **Sulfur (S)** | ≤ 0.040 | Residual impurity; typically controlled for machinability (can be increased for free-machining variants like 8637H). | | **Silicon (Si)** | 0.20 – 0.35 | Powerful deoxidizer; strengthens ferrite, improves tempering resistance. | | **Nickel (Ni)** | 0.40 – 0.70 | Significantly improves toughness (especially at low temperatures), enhances hardenability, and refines grain structure. | | **Chromium (Cr)** | 0.40 – 0.60 | Increases hardenability, wear resistance, and provides moderate corrosion resistance. Contributes to secondary hardening. | | **Molybdenum (Mo)** | 0.15 – 0.25 | A potent hardenability enhancer, particularly in larger sections. Improves tempering resistance and helps prevent temper embrittlement. | **Key Distinction from 8630:** The primary difference is the **higher carbon content** (0.35-0.40% vs. 0.28-0.33% in 8630). This gives 8637 higher as-quenched hardness and tensile strength potential, making it better suited for **through-hardening** applications where maximum core strength is required, while still being carburizable. --- ### **2. Typical Physical & Mechanical Properties** Properties vary significantly with heat treatment condition (annealed, normalized, quenched & tempered). #### **A) As-Supplied Condition (Annealed or Normalized)** *Typically supplied for machining prior to final heat treatment.* * **Hardness (Annealed):** ~ 170 – 210 HBW * **Hardness (Normalized):** ~ 200 – 240 HBW * **Tensile Strength:** 620 – 860 MPa (90 – 125 ksi) * **Yield Strength:** 415 – 620 MPa (60 – 90 ksi) * **Elongation:** 18 – 24% * **Machinability:** Fair to Good (approx. 60-65% of 1212 steel standard in annealed state). #### **B) After Quenching & Tempering (Representative Values)** *Example: Oil quenched from 845°C (1550°F), tempered at 540°C (1000°F).* * **Hardness:** 28 – 35 HRC (269 – 331 HBW) * **Tensile Strength:** 930 – 1170 MPa (135 – 170 ksi) * **Yield Strength:** 830 – 1030 MPa (120 – 150 ksi) * **Elongation:** 15 – 20% * **Impact Toughness (Charpy V-notch):** 40 – 60 J (30 – 44 ft-lb) at room temperature. #### **C) General Physical Properties** * **Density:** 7.85 g/cm³ (0.284 lb/in³) * **Modulus of Elasticity:** 190 – 210 GPa (27,500 – 30,500 ksi) * **Thermal Conductivity:** ~42 W/m·K (at 100°C) * **Thermal Expansion Coefficient:** ~11.5 µm/m·°C (20-100°C) --- ### **3. Key Features & Advantages** * **Excellent Hardenability:** The synergistic effect of Ni, Cr, and Mo allows for deep and uniform hardening, even in moderately heavy sections. * **Good Strength-Toughness Balance:** Particularly after quenching and tempering, it achieves a favorable combination of high strength and good impact resistance. * **Versatile Heat Treatment Response:** Well-suited for both **through-hardening** (for high core strength) and **case carburizing** (for a hard, wear-resistant surface with a tough, ductile core). * **Good Fatigue Strength:** The alloying elements contribute to a fine-grained microstructure with good resistance to cyclic loading. * **Moderate Cost:** Provides performance superior to plain carbon steels and many lower-alloy steels without the premium cost of highly alloyed grades like 4340. --- ### **4. Primary Applications** AISI 8637 is a workhorse alloy in sectors requiring reliable, high-strength components. * **Automotive & Transportation:** * **Gears & Pinions:** Transmission gears, differential ring gears, pinions (often carburized). * **Shafts:** Axle shafts, drive shafts, propeller shafts (through-hardened). * **Critical Fasteners:** High-strength bolts, studs, and pins. * **Suspension & Steering:** Tie rods, steering arms, torsion bars. * **Aerospace & Defense:** * Aircraft landing gear components, engine mounts, and non-critical structural fittings. * Helicopter rotor pins and drive components. * **Heavy Machinery & Equipment:** * **Construction/Mining:** Track rollers, idlers, final drive components, hydraulic cylinder rods. * **Agricultural:** Gearbox components, heavy-duty implement parts. * General machinery parts like spindles, couplings, and heavy-duty bolts. * **General Engineering:** * Tool holders, jigs, fixtures, and other components requiring a balance of strength and toughness. --- ### **5. Relevant International Standards & Specifications** | Region/System | Standard Number | Grade/Designation | Notes | | :--- | :--- | :--- | :--- | | **USA (AISI/SAE)** | SAE J404, SAE J412 | **8637** | Standard grade. Hardenability variants: **8637H** (H-band controlled). | | **USA (ASTM)** | ASTM A322, ASTM A331 | Grade 8637 | Standard specification for alloy steel bars. | | **USA (UNS)** | Unified Numbering System | **G86370** | Unique identifier. | | **Germany/EU** | DIN EN 10083-3 | **34CrNiMo6** (1.6582) | **Close but not identical equivalent.** 34CrNiMo6 has a slightly different composition range (notably, often higher Ni and Cr). It is the most commonly specified European grade for similar applications. | | **International (ISO)** | ISO 683-18 | - | Falls under the classification of alloy steels for heat treatment. Specific national equivalents are typically used. | | **Japan** | JIS G 4103 | **SNC837** | Direct Japanese equivalent. | **Important Note on Equivalents:** While 34CrNiMo6 is frequently cited as the European equivalent, its exact chemical ranges differ. For precise substitution, mechanical property requirements and hardenability should be specified, not just the grade name. --- ### **6. Heat Treatment Overview** * **Annealing:** Heat to 830-860°C (1525-1580°F), slow furnace cool. Produces a soft, machinable structure. * **Normalizing:** Heat to 870-900°C (1600-1650°F), air cool. Refines grain structure and improves homogeneity. * **Hardening (Through-Hardening):** * **Austenitize:** 830-855°C (1525-1575°F) * **Quench:** Oil (standard) or water (for very heavy sections, with caution for cracking). * **Temper:** Immediately after quenching. Temperature (e.g., 425-650°C / 800-1200°F) determines final hardness and strength. * **Case Hardening (Carburizing):** Components are carburized (e.g., at 900-925°C) to add carbon to the surface, then quenched and tempered to produce a hard case (55-62 HRC) over a tough core (typically 30-40 HRC). --- ### **Conclusion** **AISI 8637** is a **robust and reliable medium-carbon Ni-Cr-Mo alloy steel** that strikes an effective balance between performance and cost. Its higher carbon content compared to 8630 makes it particularly advantageous for **through-hardening applications where maximum core strength is essential**, while still retaining excellent carburizing capability. Valued for its **good hardenability, strength, toughness, and fatigue resistance**, it serves as a fundamental engineering material for critical, dynamically loaded components across the automotive, aerospace, and heavy equipment industries. When a project calls for a proven alloy that delivers consistent results under stress, AISI 8637 is a frequently specified and trusted choice. -:- For detailed product information, please contact sales. -: AISI 8637 Steel Specification Dimensions Size： Diameter 20-1000 mm Length <6341 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 8637 Steel Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 8637 Steel Flange -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 8637 Steel Flange -:- For detailed product information, please contact sales. -:

Packing of AISI 8637 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 2812 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