AISI 8115 Low Alloy 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 8115 Low Alloy Steel Flange, Cold Drawn Bar Product Information -:- For detailed product information, please contact sales. -: AISI 8115 Low Alloy Steel Flange, Cold Drawn Bar Synonyms -:- For detailed product information, please contact sales. -:

AISI 8115 Low Alloy Steel, Cold Drawn Bar Product Information -:- For detailed product information, please contact sales. -: ## **Product Specification: AISI 8115 Low-Alloy Case-Hardening Steel, Cold-Drawn Bar** ### **Product Designation** * **Standard Name:** AISI 8115 / SAE 8115 * **UNS Number:** G81150 * **Condition:** **Cold-Drawn** (to size, with improved surface finish and dimensional accuracy) * **Product Form:** **Round, Square, Hexagonal, or Flat Bar** * **Microstructure:** Typically supplied in a spheroidize-annealed condition prior to drawing, ensuring good machinability and a consistent response to subsequent heat treatment. ### **Overview** AISI 8115 is a low-alloy, **nickel-chromium-molybdenum case-hardening steel**. Its balanced chemistry is engineered to produce a deep, hard case with a very tough and strong core after carburizing and heat treatment. Supplied as a **cold-drawn bar**, this product offers superior surface finish, tight dimensional tolerances, and increased yield strength in the "as-delivered" state compared to hot-rolled bar. This makes it an ideal starting material for precision-machined components that require excellent wear resistance, high fatigue strength, and good impact resistance, particularly in demanding automotive and industrial applications. --- ### **1. Chemical Composition (Typical % by Weight, AISI/SAE Standard)** The alloying elements in 8115 work synergistically to provide deep hardenability and core strength. | Element | Content (%) | Role & Effect | | :--- | :--- | :--- | | **Carbon (C)** | 0.13 - 0.18 | Provides a base for core strength. Low enough to ensure excellent core toughness after case hardening. | | **Manganese (Mn)** | 0.70 - 0.90 | Increases hardenability and solid solution strength. | | **Phosphorus (P)** | ≤ 0.035 | Impurity; kept low. | | **Sulfur (S)** | ≤ 0.040 | Impurity; standard low level ensures good transverse properties. | | **Silicon (Si)** | 0.15 - 0.35 | Deoxidizer and strengthens the ferrite matrix. | | **Nickel (Ni)** | 0.20 - 0.40 | **Primary role: Enhances core toughness.** Refines grain structure and improves impact strength, especially at low temperatures. | | **Chromium (Cr)** | 0.30 - 0.50 | Enhances hardenability and promotes the formation of hard, wear-resistant carbides in the case. | | **Molybdenum (Mo)** | 0.08 - 0.15 | **Key element.** Increases hardenability significantly (especially in the core), improves tempering resistance, and enhances strength at elevated temperatures. | | **Iron (Fe)** | Balance | | --- ### **2. Physical & Mechanical Properties** **A. Physical Properties (Cold-Drawn Bar - Typical)** * **Density:** 7.85 g/cm³ (0.284 lb/in³) * **Elastic Modulus (E):** ~205 GPa (29.7 x 10⁶ psi) * **Poisson's Ratio:** 0.29 * **Thermal Conductivity:** ~52 W/m·K * **Coefficient of Thermal Expansion:** 11.5 x 10⁻⁶ /K (20-100°C) **B. Mechanical Properties (As Cold-Drawn / Annealed)** *The cold-drawing process increases strength and hardness over the annealed state.* * **Hardness (Brinell):** 187 - 229 HB (Typical range for machinable condition) * **Tensile Strength:** 620 - 860 MPa (90 - 125 ksi) * **Yield Strength (0.2% Offset):** 515 MPa (75 ksi) min. * **Elongation in 50 mm:** 15% min. * **Surface Finish:** Excellent (smooth, scale-free surface from the drawing process). * **Dimensional Tolerance:** Meets ASTM A29 cold-drawn bar tolerances (much tighter than hot-rolled). **C. Mechanical Properties (After Carburizing & Heat Treatment)** *Note: Final properties depend on case depth and tempering.* * **Surface Hardness (Case):** 58 - 63 HRC * **Effective Case Depth:** Adjustable, typically 0.5 - 2.0 mm (0.020 - 0.080 in) * **Core Hardness:** 28 - 40 HRC (providing a very strong, tough support for the hard case) * **Core Tensile Strength:** 800 - 1100 MPa (116 - 160 ksi) * **Key Advantage:** The Ni-Cr-Mo combination provides **exceptional core toughness and fatigue strength** for high-load, high-cycle applications. --- ### **3. Product Applications** AISI 8115 cold-drawn bar is specified for precision components where its combination of machinability, post-heat treatment properties, and "as-delivered" dimensional accuracy are valued. * **Automotive Powertrain (Primary Market):** * **High-Stress Gears:** Transmission gears (synchro hubs, sleeves), differential side gears and pinions, transfer case gears. * **Shafts:** Axle shafts, drive shafts, output shafts, and splined shafts. * **Engine Components:** Camshafts, fuel injection pump parts. * **Heavy Machinery & Off-Highway Equipment:** * Gears and pinions in final drives and track systems. * High-wear pins, bushings, and rollers. * **Aerospace:** * Non-critical gears, shafts, and actuator components in landing gear and flight control systems. * **Industrial Equipment:** * High-load gear sets for industrial gearboxes and reducers. * Spindles and tool holders. --- ### **4. International Standards & Designations** AISI 8115 is part of the SAE/AISI system. Its closest equivalents are other nickel-chromium-molybdenum case-hardening steels. | Standard System | Designation | Notes / Key Comparison | | :--- | :--- | :--- | | **SAE / AISI (USA)** | **SAE/AISI 8115** | Standard designation. Part of the "81xx" series (Ni-Cr-Mo). | | **UNS (USA)** | **G81150** | Unified Numbering System. | | **ASTM (USA)** | **ASTM A322** (Grade 8115) | Standard for alloy steel bars. **ASTM A29** covers cold-finished bar tolerances. | | **DIN / EN (Germany/EU)** | **~1.5752 (15NiCr13)** or **1.6523 (18CrMo4)** | Not direct equivalents. 15NiCr13 has higher Ni; 18CrMo4 has no Ni but similar applications. The exact Ni-Cr-Mo balance of 8115 is unique. | | **JIS (Japan)** | **SNC815** | The **closest direct equivalent**. Japanese JIS G4102 standard for nickel-chromium steel. | | **GB (China)** | **No direct equivalent** | Similar grades like 20CrNiMo are used but differ in composition. | --- ### **Processing & Advantages of Cold-Drawn Bar** 1. **Machining:** The cold-drawn condition provides improved machinability over hot-rolled bar due to a more consistent microstructure and better chip-breaking characteristics. The smooth surface also reduces tool wear. 2. **Near-Net-Shape:** Tight tolerances and good straightness reduce machining time and material waste. 3. **Improved Strength:** The cold work imparts higher yield and tensile strength in the as-delivered state, which can be beneficial for handling and some intermediate forming operations. 4. **Subsequent Heat Treatment:** The material must be fully austenitized during carburizing, which will remove the effects of cold work. The final properties are determined by the alloy chemistry and the heat treatment cycle, not the prior cold drawing. ### **Summary** **AISI 8115 Cold-Drawn Bar** is a premium, ready-to-machine form of a high-performance **Ni-Cr-Mo case-hardening steel**. It is selected for applications demanding an optimal balance of core toughness, deep hardenability, and high fatigue strength after carburizing. The cold-drawn production process delivers dimensional precision, a superior surface finish, and improved machinability, making it a cost-effective choice for manufacturing high-volume, precision components such as automotive transmission gears and shafts. Its closest international counterpart, **JIS SNC815**, underscores its role as a globally recognized material for critical, high-stress mechanical parts. -:- For detailed product information, please contact sales. -: AISI 8115 Low Alloy Steel, Cold Drawn Bar Specification Dimensions Size： Diameter 20-1000 mm Length <4142 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 8115 Low Alloy Steel, Cold Drawn Bar Properties -:- For detailed product information, please contact sales. -:

Applications of AISI 8115 Low Alloy Steel Flange, Cold Drawn Bar -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI 8115 Low Alloy Steel Flange, Cold Drawn Bar -:- For detailed product information, please contact sales. -:

Packing of AISI 8115 Low Alloy Steel Flange, Cold Drawn Bar -:- 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 613 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