AISI 4137H 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 4137H Steel Flange Product Information -:- For detailed product information, please contact sales. -: AISI 4137H Steel Flange Synonyms -:- For detailed product information, please contact sales. -:

AISI 4137H Steel Product Information -:- For detailed product information, please contact sales. -: # AISI 4137H Alloy Steel Product Overview ## **Introduction** AISI 4137H is a chromium-molybdenum alloy steel supplied under the "H" designation, indicating it conforms to specific hardenability band requirements as defined by ASTM standards. This medium-carbon, low-alloy steel provides a predictable and consistent response to heat treatment, making it particularly valuable for high-strength components where uniform through-hardening in larger cross-sections is critical. The "H" designation ensures reproducible mechanical properties regardless of production lot variations. ## **International Standards & Designations** * **USA:** AISI 4137H, ASTM A304 (Standard Specification for Carbon and Alloy Steel Bars Subject to End-Quench Hardenability Requirements) * **Europe:** Equivalent to **1.6563H** (34CrMo4H/35CrMo4H) with H-band specifications * **Japan:** Equivalent to SCM435H (JIS G4052) * **China:** Equivalent to 35CrMoH (GB/T 5216) * **ISO:** 34CrMo4 (ISO 683-18) with H-band control * **UNS:** H41370 ## **Chemical Composition (Weight % - H-Steel Ranges)** The composition is controlled within specified limits to ensure consistent hardenability within the prescribed "H-band." | Element | Min (%) | Max (%) | Primary Function | | :--- | :--- | :--- | :--- | | **Carbon (C)** | 0.33* | 0.40* | Provides core strength and hardenability. Ranges ensure consistent hardenability band. | | **Manganese (Mn)** | 0.70 | 1.00 | Enhances hardenability and strength; range ensures predictable response. | | **Phosphorus (P)** | - | 0.030 | Residual element (controlled for embrittlement). | | **Sulfur (S)** | - | 0.030 | Residual element (controlled for machinability and cleanliness). | | **Silicon (Si)** | 0.15 | 0.35 | Deoxidizer, solid solution strengthener. | | **Chromium (Cr)** | 0.80 | 1.10 | Improves hardenability, wear, and corrosion resistance. | | **Molybdenum (Mo)** | 0.15 | 0.25 | Enhances hardenability, high-temperature strength, reduces temper embrittlement. | | **Boron (B)** | (Optional) | 0.0005-0.003 | May be added in trace amounts to significantly boost hardenability without major composition changes. | ***Note:** The key difference from standard 4137 is the **controlled carbon range for hardenability** rather than a fixed minimum. The actual aim carbon is typically 0.35-0.40%, but the H-band specification allows slight variation across heats to achieve the same hardenability. This is the fundamental principle of H-steels.* ## **Hardenability (Jominy End-Quench Test)** The defining characteristic of AISI 4137H is its guaranteed hardenability band per ASTM A304. Typical hardness values (HRC) at specified distances from the quenched end: | Distance from Quenched End (1/16 in.) | Typical Hardness Range (HRC) | | :--- | :--- | | 1 | 52 - 58 | | 4 | 48 - 55 | | 8 | 40 - 50 | | 12 | 33 - 45 | | 16 | 28 - 40 | | 20 | 25 - 36 | | 28 | 22 - 32 | *The actual hardenability band (H-band) is specified by the purchaser (e.g., H + specific band number). This ensures that the depth of hardening is predictable and consistent from lot to lot.* ## **Physical & Mechanical Properties** ### **Physical Properties (Typical - Annealed)** * **Density:** 7.85 g/cm³ * **Modulus of Elasticity:** 205 GPa (29.7 x 10⁶ psi) * **Poisson's Ratio:** 0.29 * **Thermal Conductivity:** ~42 W/m·K (at 100°C) * **Coefficient of Thermal Expansion:** 11.7 x 10⁻⁶ /K (20-100°C) * **Magnetic Properties:** Ferromagnetic ### **Mechanical Properties (After Quenching & Tempering)** *Properties are highly dependent on tempering temperature. Below are typical achievable ranges.* | Condition | Tensile Strength | Yield Strength | Elongation (%) | Reduction in Area (%) | Hardness (HRC) | Charpy V-Notch Impact | | :--- | :--- | :--- | :--- | :--- | :--- | :--- | | **High Strength**
(Low Temp Tempered) | 1550 - 1725 MPa | 1380 - 1520 MPa | 10 - 13 | 40 - 50 | 48 - 52 | 15 - 25 J | | **Medium Strength**
(Medium Temp Tempered) | 1240 - 1380 MPa | 1100 - 1240 MPa | 13 - 16 | 45 - 55 | 40 - 44 | 30 - 45 J | | **Toughness Oriented**
(High Temp Tempered) | 860 - 1030 MPa | 760 - 930 MPa | 18 - 22 | 50 - 60 | 30 - 36 | 50 - 70 J | ## **Heat Treatment** **Standard Heat Treatment Cycle:** 1. **Austenitizing:** 830°C - 860°C (1525°F - 1580°F) 2. **Quenching:** Rapid oil quench (or water quench for very large sections, with caution for distortion/cracking) 3. **Tempering:** 425°C - 650°C (800°F - 1200°F) for 1-2 hours per inch of thickness, then air cool. 4. **Stress Relieving (Optional):** 150°C - 200°C (300°F - 400°F) after rough machining. **Case Hardening Suitability:** AISI 4137H is also an excellent candidate for **carburizing** or **carbonitriding** to produce a very hard, wear-resistant surface (up to 60+ HRC) while maintaining a tough, strong core (~30-45 HRC). ## **Product Applications** AISI 4137H is specified for safety-critical and high-performance components where consistent heat treatment results are mandatory: * **Automotive & Heavy Truck:** **Axle shafts** (front and rear), **crankshafts**, **connecting rods**, **king pins**, **steering knuckles**, **transmission gears**, and high-strength **wheel hubs**. * **Agriculture & Construction:** **Final drive gears**, **track rollers**, **pivot shafts**, **planetary carriers**, and high-load **hydraulic cylinder rods** for excavators and tractors. * **Oil & Gas:** **Drill collars**, **tool joints**, **sucker rods**, **mandrels**, and **valve stems** requiring consistent strength in large diameters. * **Power Transmission & Industrial:** **Heavy-duty gearbox shafts**, **sprockets**, **couplings**, **forged rolls**, and **high-strength bolts** (ASTM A490 type performance). * **Aerospace & Defense:** **Landing gear components**, **missile body sections**, **armor attachments**, and other structural fittings. * **Railroad:** **Axles**, **coupler components**, and **traction motor shafts**. ## **Key Advantages of the "H" Designation** 1. **Predictable Hardenability:** Guaranteed Jominy band ensures uniform depth of hardening and consistent core properties, regardless of slight heat-to-heat chemistry variations. This is crucial for **large-diameter components**. 2. **Design Flexibility:** Engineers can design based on guaranteed minimum mechanical properties at the center of a section. 3. **Manufacturing Reliability:** Reduces heat treatment rejects and allows for more consistent machining performance after treatment. 4. **Interchangeability:** Components made from different production lots will have identical response to heat treatment, ensuring assembly and performance consistency. 5. **Superior to Standard Grades:** For critical applications, 4137H provides a reliability and consistency edge over standard AISI 4137. ## **Manufacturing & Processing** * **Machinability:** Fair (approximately 60% of 1212 steel) in annealed condition. Improves with proper heat treatment to a uniform hardness. * **Weldability:** Fair. Requires preheating to 150-260°C (300-500°F) and post-weld heat treatment (PWHT) to restore mechanical properties in the heat-affected zone (HAZ). Not typically used for fabrications. * **Forging:** Heat to 1150-1260°C (2100-2300°F), finish forging above 870°C (1600°F). Anneal after forging to refine grain structure. * **Grindability:** Good with proper wheels and coolant. Susceptible to grinding burns if excessive heat is generated. ## **Available Product Forms** * Hot-Rolled or Cold-Drawn Bars (Rounds, Squares, Hexagons) * Forged Billets, Blooms, and Custom Shapes * Seamless Mechanical Tubing ## **Comparison with Key Grades** * **vs. AISI 4137:** The **H** version offers guaranteed hardenability bands; the standard grade has fixed chemistry but no hardenability guarantee. **4137H is preferred for critical applications.** * **vs. AISI 4140H:** 4137H has slightly lower carbon (typically ~0.37% vs. ~0.40% aim), offering a marginally better combination of toughness and weldability at high strength levels. * **vs. AISI 4340:** 4137H is a more cost-effective, nickel-free alternative where the ultra-high toughness of 4340 is not required. ## **Quality & Inspection** * **Hardenability Report:** Mill certification includes actual Jominy test results showing compliance with the specified H-band. * **Ultrasonic Testing:** Often specified for bar stock to ensure internal soundness. * **Grain Size:** Typically ASTM 5 or finer. ## **Disclaimer** The information provided is for general reference. For specific design or procurement, always consult the relevant ASTM/ISO standards, mill certifications, and engage with qualified metallurgical engineering expertise. Mechanical properties are highly dependent on section size, heat treatment parameters, and manufacturing processes. -:- For detailed product information, please contact sales. -: AISI 4137H Steel Specification Dimensions Size： Diameter 20-1000 mm Length <4038 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 4137H Steel Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 4137H Steel Flange -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 4137H Steel Flange -:- For detailed product information, please contact sales. -:

Packing of AISI 4137H 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 509 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