AISI E4340 H 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 E4340 H Steel Flange, annealed, 25 mm round Product Information -:- For detailed product information, please contact sales. -: AISI E4340 H Steel Flange, annealed, 25 mm round Synonyms -:- For detailed product information, please contact sales. -:

AISI E4340 H Steel, annealed, 25 mm round Product Information -:- For detailed product information, please contact sales. -: ## **Technical Specification: AISI 4340H (UNS H43400) Alloy Steel, Annealed Condition, 25 mm Round Bar** ### **1. Product Overview** This product specification defines **AISI 4340H alloy steel**, a **hardenability-controlled variant** of the standard AISI 4340 grade, supplied in the **fully annealed condition** as a **25 mm (1 inch) diameter precision round bar**. The "H" suffix indicates the chemical composition is tailored to meet specified hardenability bands as defined by end-quench (Jominy) testing standards. This provides greater predictability and consistency in the depth and uniformity of hardening after final heat treatment, especially critical for mass-produced components. The annealed state delivers optimal softness and machinability, making it an ideal starting material for complex machining prior to quenching and tempering. **Core Value Proposition:** * **Guaranteed Hardenability:** Chemical composition is controlled to ensure the material falls within predefined hardenability bands (e.g., H-band limits per SAE J1268), leading to more consistent mechanical properties after heat treatment across different production batches. * **Superior Machinability:** The annealed microstructure provides excellent chip formation and low tool wear, reducing manufacturing costs for intricate parts. * **Consistent Performance:** The combination of controlled hardenability and a uniform soft starting condition minimizes variance in final part performance, crucial for automotive, aerospace, and heavy machinery applications. * **Precision Form:** The 25 mm round bar is typically centerless turned or cold drawn to tight dimensional tolerances, offering a ready-to-machine product with good surface finish. --- ### **2. Chemical Composition (Weight %)** The composition for 4340H is based on standard 4340 but with ranges adjusted to meet hardenability requirements rather than fixed minima/maxima. The *actual* composition will vary within these broader limits to hit the target Jominy curve. | Element | AISI 4340H Typical Range (%) | Role & Hardenability Impact | | :--- | :--- | :--- | | **Iron (Fe)** | Balance | Base Element | | **Carbon (C)** | 0.37 - 0.44 | Primary determinant of hardness potential. Controlled to center the hardenability band. | | **Manganese (Mn)**| 0.60 - 0.90 | **Key hardenability adjuster.** Range is wider than standard 4340 to fine-tune Jominy curve. | | **Silicon (Si)** | 0.15 - 0.35 | Deoxidizer; has a moderate effect on hardenability. | | **Nickel (Ni)** | 1.55 - 2.00 | Significant effect on hardenability and core toughness. | | **Chromium (Cr)** | 0.65 - 0.95 | Strong hardenability enhancer; range adjusted for band control. | | **Molybdenum (Mo)**| 0.20 - 0.30 | Potent hardenability element; crucial for through-hardening of sections like 25mm round. | | **Sulfur (S)** | ≤ 0.040 | Residual; may be slightly higher for improved machinability (e.g., 4340H Modified). | | **Phosphorus (P)** | ≤ 0.035 | Residual. | **Hardenability Note:** The defining characteristic is compliance with **SAE J1268** H-band limits. The mill's *heat chemistry* is set to ensure the end-quench test results fall between the specified minimum and maximum distances for given hardness points (e.g., at J=6mm, J=12mm). --- ### **3. Typical Mechanical & Physical Properties (Annealed Condition)** *Properties are for the "as-supplied" annealed 25mm round bar, optimized for machinability.* | Property | Typical Value / Specification | Test Standard / Note | | :--- | :--- | :--- | | **Hardness** | **187 - 217 HB** (Brinnell) / **85 - 95 HRB** | ASTM E10 / E18. Standard annealed condition. | | **Tensile Strength** | ~ 650 MPa (94 ksi) | ASTM E8 | | **Yield Strength (0.2% Offset)** | ~ 415 MPa (60 ksi) | ASTM E8 | | **Elongation (in 50mm)** | ≥ 22% | ASTM E8 | | **Reduction of Area** | ≥ 50% | ASTM E8 | | **Machinability Rating** | ~ 55% (of B1112 steel) | Good for an alloy steel; produces discontinuous chips. | | **Modulus of Elasticity** | 205 GPa (29.7 x 10⁶ psi) | - | | **Density** | 7.85 g/cm³ (0.284 lb/in³) | - | | **Microstructure** | Fine **Pearlite and Ferrite** (lamellar or spheroidized) | Uniform structure for predictable hardening. | --- ### **4. Hardenability & Subsequent Heat Treatment** * **Hardenability Assurance:** As an H-steel, a **Jominy Hardenability Test Certificate** is available for each heat lot, showing the hardness profile from the quenched end. This data is used to model the final properties in a 25mm round bar after oil quenching. * **Final Heat Treatment:** After machining, the component will be **austenitized** (typically 830-870°C / 1525-1600°F), **oil quenched**, and **tempered** to the desired strength level. The guaranteed hardenability ensures a uniform through-hardened microstructure in this diameter, with minimal risk of soft core formation. --- ### **5. Target Applications** This material is specified for high-volume, critical components where heat treatment consistency is non-negotiable. * **Automotive Transmission & Drivetrain:** **Gear shafts**, **pinions**, **synchronizer hubs**, and **drive axles** where consistent case depth and core strength are vital for durability and noise control. * **Heavy-Duty Trucking:** **Crankshafts**, **king pins**, **wheel spindles**, and **suspension components**. * **Aerospace (Secondary Structures & Systems):** **Actuator shafts**, **landing gear bolts**, and **engine mounting components**. * **Industrial Machinery:** **Hydraulic piston rods**, **spindles**, **high-strength fasteners**, and **gear blanks**. * **Oil & Gas:** **Valve stems**, **pump shafts**, and **tool joints** for downhole equipment. --- ### **6. International Standards & Procurement** The "H" designation is primarily an SAE/AISI system, with equivalents in other standards. | Standard | Designation | Equivalent / Note | | :--- | :--- | :--- | | **SAE / AISI (USA)** | **4340H** (UNS H43400) | **Primary Standard.** Defined by hardenability bands in SAE J1268. | | **ASTM (USA)** | **A304** | Standard specification for steel bars, alloy, subject to end-quench hardenability requirements. **This is the key governing product standard.** | | **SAE (USA)** | **J1268** | Standard method for hardenability band calculation and reporting. | | **ISO** | ISO 683-18:1996 | Similar hardenability-controlled grades are specified (e.g., requirements for Jominy depth). Direct equivalent: **1.6562** with hardness controls. | | **EN (Europe)** | EN 10083-3 | **34CrNiMo6 + H** | The "+H" indicates hardenability requirements per EN ISO 642. | | **JIS (Japan)** | JIS G4052 | **SCr440H** | Japanese alloy structural steels for machine construction with guaranteed hardenability. | | **GB (China)** | GB/T 5216 | **40CrNiMoAH** | Chinese guaranteed hardenability alloy structural steel. | **Procurement Specification:** For guaranteed quality, the purchase order should specify: 1. **Material Grade:** AISI 4340H per ASTM A304. 2. **Condition:** Annealed. 3. **Form & Size:** 25 mm (+/- tolerance) Round Bar, centerless turned. 4. **Hardenability Requirement:** e.g., "To meet SAE J1268 H-band limits for 4340H." 5. **Certification:** Requirement for a **Mill Test Report** including full chemical analysis and the **actual Jominy Hardenability Test Certificate** for the heat lot. -:- For detailed product information, please contact sales. -: AISI E4340 H Steel, annealed, 25 mm round Specification Dimensions Size： Diameter 20-1000 mm Length <6254 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 E4340 H Steel, annealed, 25 mm round Properties -:- For detailed product information, please contact sales. -:

Applications of AISI E4340 H Steel Flange, annealed, 25 mm round -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI E4340 H Steel Flange, annealed, 25 mm round -:- For detailed product information, please contact sales. -:

Packing of AISI E4340 H Steel Flange, annealed, 25 mm round -:- 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 2725 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