JIS SKD12 Tool 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. -: JIS SKD12 Tool Steel Flange Product Information -:- For detailed product information, please contact sales. -: JIS SKD12 Tool Steel Flange Synonyms -:- For detailed product information, please contact sales. -:

JIS SKD12 Tool Steel Product Information -:- For detailed product information, please contact sales. -: ### **Product Technical Datasheet: JIS SKD12 High-Carbon, High-Chromium Cold Work Tool Steel** --- #### **1. Product Overview** **JIS SKD12** is a **high-carbon, high-chromium, air-hardening cold work tool steel** specified under Japanese Industrial Standard (JIS) G 4404. It is a close variant of the widely used SKD11 (AISI D2) grade but is distinguished by a **significantly lower molybdenum content**. This compositional adjustment positions SKD12 as a **more cost-effective alternative** for applications that benefit from the high wear resistance and dimensional stability of the high-chromium tool steel family, but where the extreme performance characteristics (particularly deep hardenability and tempering resistance) of SKD11 are not strictly required. It offers a compelling balance of **good wear resistance, moderate toughness, and excellent polishability**. --- #### **2. International Standard Cross-Reference** SKD12 is a standard grade with well-defined equivalents, often seen as a leaner version of D2-type steels. | Standard System | Equivalent / Similar Grade | Note | | :--- | :--- | :--- | | **JIS G 4404 (Japan)** | **SKD12** | Defining Standard | | **AISI (USA)** | **D3** | The primary direct equivalent. | | **DIN (Germany)** | **1.2080 / X210Cr12** | High-chromium steel with lower Mo. | | **BS (UK)** | **BD3** | High-Carbon, High-Chromium Type. | | **ISO** | **~210Cr12** | ISO chemical designation. | | **GB (China)** | **Cr12** | China's equivalent with similar low-Mo composition. | --- #### **3. Chemical Composition (Typical, weight % per JIS G 4404)** The key differentiator from SKD11 is the minimal molybdenum and vanadium content. | Element | Carbon (C) | Silicon (Si) | Manganese (Mn) | Chromium (Cr) | Molybdenum (Mo) | Vanadium (V) | Phosphorus (P) | Sulfur (S) | | :--- | :--- | :--- | :--- | :--- | :--- | :--- | :--- | :--- | | **Content (%)** | 1.90 - 2.20 | ≤ 0.40 | ≤ 0.60 | 11.00 - 13.00 | ≤ 0.50 (Typ.) | ≤ 0.30 (Typ.) | ≤ 0.030 | ≤ 0.030 | **Function of Key Alloying Elements & Comparison to SKD11:** * **Carbon (1.90-2.20%):** **Higher than SKD11.** This increases the volume of hard carbides, potentially offering even higher wear resistance in less-tough applications. * **Chromium (11.00-13.00%):** Similar to SKD11, forms hard chromium carbides (M₇C₃) for wear resistance. * **Molybdenum & Vanadium (Low):** The **critical difference**. The low levels of Mo (<0.5%) and V (<0.3%) result in: * **Lower hardenability** – Less suitable for very thick sections. * **Reduced secondary hardening response** – Lower hot hardness and tempering resistance. * **Less refined grain structure** – Can impact toughness and polishability compared to SKD11. * **Primary Carbide Type:** Like SKD11, it contains a high volume of large, blocky **chromium carbides**. --- #### **4. Physical & Mechanical Properties** * **Density:** ~7.70 g/cm³. * **Thermal Conductivity:** Low (~20-22 W/m·K at 20°C). * **Thermal Expansion Coefficient:** ~10.4 x 10⁻⁶ /K. * **Machinability (Annealed State):** **Poor.** Similar to SKD11; the high carbon and chromium carbide content makes it abrasive and difficult to machine. * **Grindability:** **Fair to Poor.** Requires careful technique to avoid cracking. * **Hardenability:** **Good (Air-Hardening), but less than SKD11.** Suitable for through-hardening of medium to large sections, but maximum hardenable size is less than that of SKD11. * **Dimensional Stability:** **Very Good.** Benefits from air hardening, though dimensional change can be slightly more pronounced than SKD11 due to different transformation characteristics. * **Polishing & Finishing:** **Excellent.** Can achieve very fine mirror finishes, making it suitable for certain mold applications. * **Typical Achievable Hardness:** * **Annealed State:** ~ 220 - 255 HB * **Hardened & Tempered State:** **58 - 62 HRC.** The high carbon allows it to reach high hardness, but with potentially greater brittleness. --- #### **5. Heat Treatment Guidelines** * **Forging:** Heat slowly to 1050-1100°C. Forge between 1050-850°C. Cool very slowly (in furnace or insulating medium). * **Annealing:** Heat to 850-880°C, hold, then furnace cool very slowly to 500°C, then air cool. * **Stress Relieving (after rough machining):** 600-650°C. * **Hardening:** 1. **Preheating:** **Essential.** Preheat at 400-500°C and 800-850°C. 2. **Austenitizing:** **950-980°C.** **Note: Lower than SKD11.** Higher temperatures risk excessive grain growth and retained austenite. 3. **Quench:** Cool in **still air or forced air**. Oil quenching can be used for smaller sections but increases distortion risk. * **Tempering:** **Double tempering is strongly recommended.** * Temper immediately after quenching. * **Typical Cycle:** **180-220°C** for 2+ hours, twice. Avoid high tempering temperatures (>400°C) as it lacks strong secondary hardening and will soften significantly. * **Sub-Zero Treatment:** Can be beneficial to reduce retained austenite and stabilize dimensions, though less critical than for SKD11 if low tempering is used. --- #### **6. Product Applications** SKD12 is used in applications requiring high wear resistance and good stability, often where cost is a consideration and extreme toughness is not the primary driver. * **Blankng and Piercing Dies:** For **ferrous and non-ferrous metals** in medium to high production runs, particularly where abrasive wear is the main failure mode. * **Forming Rolls and Roller Dies:** For cold rolling and forming of metal sheets and wires. * **Shear and Slitter Blades:** **Industrial knives and blades** for cutting paper, cardboard, plastics, and thin metals. * **Molds:** **Plastic injection molds** for general-purpose and abrasive plastics where high polishability is required. Often used for mold inserts and cores. * **Thread Rolling Dies:** For less severe thread rolling applications. * **Wear Parts:** **Liners, guides, and wear plates** in machinery. * **Gauges and Tools:** **Go/no-go gauges** and precision tools requiring dimensional stability. --- #### **7. Advantages & Limitations** | Advantages | Limitations | | :--- | :--- | | • **Very high wear and abrasion resistance** due to high carbon and chromium carbide content.
• **Good dimensional stability** from air hardening.
• **Excellent polishability** to a mirror finish.
• **More cost-effective** than SKD11/D2 due to lower alloy content.
• **Suitable for large, but not extreme, cross-sections.** | • **Lower toughness and impact resistance** compared to SKD11, making it more prone to chipping and cracking under shock loads.
• **Lower hardenability and tempering resistance** than SKD11.
• **Poor machinability and grindability.**
• **High carbon content can lead to carbide banding/segregation** in large sections, affecting isotropy.
• **Not corrosion resistant** (chromium is tied up in carbides). | --- #### **8. Selection Guidance: SKD12 vs. SKD11** * **Choose SKD12 (D3) when:** The application demands **maximum wear resistance on a budget**, involves **minimal shock**, and the **section size is within its hardenability limits**. It is a classic choice for **blanking dies for thin, abrasive materials**. * **Choose SKD11 (D2) when:** You need a **better balance of wear resistance and toughness**, require **deeper hardenability for very thick sections**, need **better performance at slightly elevated temperatures (secondary hardening)**, or are making **complex tools subject to moderate shock**. * **General Rule:** SKD11 is the more versatile, high-performance grade. SKD12 is a specialized, cost-focused grade for wear-dominated, low-shock applications. **Conclusion:** JIS SKD12 (AISI D3) is a **specialized, high-wear member of the high-chromium tool steel family.** Its defining characteristic is its **very high carbon content**, which prioritizes abrasion resistance above all else. While it sacrifices some toughness, hardenability, and thermal stability compared to SKD11, it remains a **highly effective and economical solution** for a well-defined range of cold-work tooling where wear is the sole or primary concern. For toolmakers working with abrasive materials under controlled conditions, SKD12 offers a **viable and cost-conscious alternative** to the more premium SKD11 grade. -:- For detailed product information, please contact sales. -: JIS SKD12 Tool Steel Specification Dimensions Size： Diameter 20-1000 mm Length <6800 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. -: JIS SKD12 Tool Steel Properties -:- For detailed product information, please contact sales. -:

Applications of JIS SKD12 Tool Steel Flange -:- For detailed product information, please contact sales. -: Chemical Identifiers JIS SKD12 Tool Steel Flange -:- For detailed product information, please contact sales. -:

Packing of JIS SKD12 Tool 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 3271 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