SCM420 Carburizing Bearing 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. -: SCM420 Carburizing Bearing Steel Flange (Composition Spec) Product Information -:- For detailed product information, please contact sales. -: SCM420 Carburizing Bearing Steel Flange (Composition Spec) Synonyms -:- For detailed product information, please contact sales. -:

SCM420 Carburizing Bearing Steel (Composition Spec) Product Information -:- For detailed product information, please contact sales. -: # **Product Technical Datasheet: SCM420 Carburizing Bearing Steel** ## **1. Product Overview** **SCM420** is a chromium‑molybdenum (Cr‑Mo) alloy steel, classified under the Japanese Industrial Standards (JIS) as a **carburizing (case‑hardening) steel**. It is specifically designed to achieve a high‑surface‑hardness, wear‑resistant case combined with a tough, ductile core through the carburizing heat treatment process. While not a dedicated bearing steel in the classical sense (like SAE 52100), SCM420 is extensively used for **bearings, gears, and transmission components** requiring exceptional surface durability and fatigue resistance under high contact stresses. The steel is supplied in the annealed or spheroidized condition to facilitate machining prior to heat treatment. ## **2. Governing International Standards** SCM420 is primarily defined by the **Japanese Industrial Standard JIS G 4105 – Chromium‑Molybdenum Steels**. Its closest international equivalents include: * **AISI / SAE:** 4120, 5120 (approximate equivalents with slight compositional variations) * **DIN / EN:** 1.7213 / 20CrMo5 (Europe) * **GB:** 20CrMo (China) * **ISO 683‑11:** Designated for case‑hardening steels. ## **3. Chemical Composition** The composition is optimized for deep‑hardenability and core strength after carburizing. Standard composition ranges (in weight %) are: * **Carbon (C):** 0.18 – 0.23% * **Silicon (Si):** 0.15 – 0.35% * **Manganese (Mn):** 0.60 – 0.85% * **Phosphorus (P):** ≤ 0.030% * **Sulfur (S):** ≤ 0.030% * **Chromium (Cr):** 0.90 – 1.20% * **Molybdenum (Mo):** 0.15 – 0.30% **Key Feature:** The strategic combination of **Chromium and Molybdenum** ensures sufficient hardenability for a deep, hardened case and a strong core, even in moderately sized components, while maintaining good machinability in the annealed state. ## **4. Typical Properties & Heat Treatment Response** ### **As‑Supplied Condition (Annealed):** * **Hardness:** 140 – 180 HBW * **Tensile Strength:** ~ 500 – 650 MPa * **Microstructure:** Ferrite + Pearlite (spheroidized for optimal machinability) ### **After Carburizing & Heat Treatment:** A typical process sequence involves: Carburizing → Quenching → Low‑Temperature Tempering. * **Case Properties:** * **Surface Hardness:** 58 – 63 HRC * **Effective Case Depth (ECD):** Variable, typically 0.5 – 1.5 mm (0.020” – 0.060”) at 550 HV. * **Microstructure:** High‑carbon martensite with retained austenite and fine carbides. * **Core Properties:** * **Hardness:** 30 – 45 HRC (depending on component size and quench severity) * **Microstructure:** Low‑carbon martensite or bainite, providing high strength and toughness. * **Core Tensile Strength:** 1000 – 1300 MPa (approx.) ### **Physical Properties:** * **Modulus of Elasticity:** 205 GPa * **Density:** 7.85 g/cm³ * **Coefficient of Thermal Expansion:** ~ 11.5 x 10⁻⁶/°C (20–100°C) ## **5. Key Characteristics & Engineering Advantages** * **Excellent Case Hardness & Wear Resistance:** The carburized case provides outstanding resistance to abrasive wear, pitting, and rolling contact fatigue. * **Strong & Tough Core:** The alloying elements ensure a high‑strength core that supports the hard case, resisting bending and impact loads. * **Good Hardenability:** The Cr‑Mo combination allows for effective case hardening of components with moderate cross‑sections, providing a good depth of hardening with oil quenching. * **Superior Fatigue Strength:** The compressive residual stresses in the carburized case significantly enhance bending and contact fatigue life. * **Good Machinability:** In the properly annealed or spheroidized condition, it offers good machinability for producing precise components before heat treatment. * **Cost‑Effective Performance:** Offers a favorable balance of performance and cost compared to higher‑alloy carburizing steels like SCM822 or SNCM420. ## **6. Typical Applications** SCM420 is widely used for high‑performance, case‑hardened mechanical components, particularly in automotive and industrial machinery: * **Bearings:** Needle roller bearing races, slewing rings, cam followers, and large‑sized rolling element bearings. * **Gears & Transmission:** Automotive transmission gears (gears, synchronizer hubs), differential pinions, industrial gearbox gears, and shafts. * **Automotive Components:** Crankshafts, camshafts, piston pins, and universal joint yokes. * **General Machinery:** Pins, bushings, couplings, and heavily loaded shafts requiring a wear‑resistant surface. * **Oil & Gas:** Components for downhole tools and valves requiring surface hardness. ## **7. Summary** **SCM420** is a versatile and reliable **chromium‑molybdenum carburizing steel** that delivers an optimal combination of a **super‑hard, wear‑resistant surface** and a **tough, load‑bearing core**. Its well‑balanced chemistry makes it a prime choice for manufacturing critical, fatigue‑resistant components like bearings and gears, especially where cost‑performance ratio is a key consideration. Its standardized specifications under JIS and equivalence to major international grades ensure its global availability and consistent quality for demanding engineering applications. -:- For detailed product information, please contact sales. -: SCM420 Carburizing Bearing Steel (Composition Spec) Specification Dimensions Size： Diameter 20-1000 mm Length <5864 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. -: SCM420 Carburizing Bearing Steel (Composition Spec) Properties -:- For detailed product information, please contact sales. -:

Applications of SCM420 Carburizing Bearing Steel Flange (Composition Spec) -:- For detailed product information, please contact sales. -: Chemical Identifiers SCM420 Carburizing Bearing Steel Flange (Composition Spec) -:- For detailed product information, please contact sales. -:

Packing of SCM420 Carburizing Bearing Steel Flange (Composition Spec) -:- 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 2335 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