Oil-Hardening Cold Work Tool Steel Flange (UNS T91501)

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. -: Oil-Hardening Cold Work Tool Steel Flange (UNS T91501) Product Information -:- For detailed product information, please contact sales. -: Oil-Hardening Cold Work Tool Steel Flange (UNS T91501) Synonyms -:- For detailed product information, please contact sales. -:

Oil-Hardening Cold Work Tool Steel (UNS T91501) Product Information -:- For detailed product information, please contact sales. -: # **Product Introduction: Oil-Hardening Cold Work Tool Steel (UNS T91501 / AISI Type O1)** ## **Overview** **Oil-Hardening Cold Work Tool Steel**, designated as **UNS T91501** and commonly known as **AISI Type O1**, is a versatile, **low-alloy, oil-quenching tool steel** renowned for its **excellent machinability, good dimensional stability, and balanced wear resistance**. As one of the most widely used and readily available tool steels globally, O1 provides a cost-effective solution for a broad range of tooling applications. Its oil-hardening characteristic offers a favorable balance between minimizing distortion and achieving sufficient hardness, making it a preferred choice for **precision tools, gauges, dies, and blades** that require a combination of toughness, ease of fabrication, and reliable performance. --- ## **Chemical Composition (Typical Weight %)** The composition is a balanced, low-alloy system designed for reliable oil-hardening response. | Element | Content (%) | Role in Oil-Hardening | | :--- | :--- | :--- | | **Carbon (C)** | 0.85 - 1.00 | Primary hardener; forms carbides for wear resistance. | | **Manganese (Mn)** | 1.00 - 1.40 | Increases hardenability and strength; stabilizes austenite. | | **Chromium (Cr)** | 0.40 - 0.60 | Enhances hardenability, wear resistance, and toughness. | | **Tungsten (W)** | 0.40 - 0.60 | Forms hard carbides for wear resistance and reduces grain growth. | | **Vanadium (V)** | 0.15 - 0.30 | Powerful grain refiner; improves toughness and wear resistance. | | **Silicon (Si)** | 0.10 - 0.30 | Deoxidizer; increases strength and hardenability. | | **Sulfur (S)** | ≤ 0.03 | - | | **Phosphorus (P)** | ≤ 0.03 | - | | **Iron (Fe)** | **Balance** | Base metal. | **Key Feature:** The combination of **manganese and chromium** provides sufficient hardenability for oil quenching in moderate sections, while **tungsten and vanadium** contribute to wear resistance and grain refinement without excessively compromising machinability. --- ## **Physical & Mechanical Properties** *Properties are for material in the hardened and tempered condition (typically ~60 HRC).* | Property | Typical Value / Description | | :--- | :--- | | **Density** | 7.86 g/cm³ (0.284 lb/in³) | | **Hardness (Annealed)** | 183 - 212 HB | | **Hardness (Hardened & Tempered)** | **57 - 62 HRC** (Typically 59-61 HRC) | | **Wear Resistance** | **Good.** Suitable for many cold work applications; superior to low-carbon steels but less than high-alloy grades like D2 or A2. | | **Toughness** | **Good to Very Good.** Better than many air-hardening grades of equivalent hardness due to its lower alloy content and oil-quench process. | | **Dimensional Stability** | **Good.** Oil quenching produces less distortion than water quenching but more than air hardening. Careful quenching technique is key. | | **Machinability (Annealed)** | **Excellent.** One of the most machinable tool steels (~90% of 1% carbon steel). A primary advantage of O1. | | **Grindability** | **Very Good.** Grinds easily compared to high-vanadium or high-chromium steels. | | **Minimum Hardenable Depth** | ~5 mm (0.2 in) from surface in oil quench. | | **Thermal Conductivity** | ~ 40 W/m·K (Relatively high for a tool steel) | | **Coefficient of Thermal Expansion** | ~ 11.5 × 10⁻⁶/°C | --- ## **Heat Treatment Guidelines** Proper heat treatment is critical for achieving optimal properties with minimal distortion. | Process | Parameters | Purpose/Notes | | :--- | :--- | :--- | | **Annealing** | Heat to 760-790°C (1400-1450°F), slow furnace cool. | Achieves ~200 HB for optimal machinability. | | **Preheating** | 650-700°C (1200-1300°F). **Essential.** | Reduces thermal shock and distortion. | | **Austenitizing** | **780-810°C (1440-1490°F).** Soak: 20-30 min/in. | Critical range: Higher temps increase hardness but also distortion risk. | | **Quenching** | **Quench in warm, circulating oil (50-70°C).** | Agitation is crucial for uniformity. Cool to 50-65°C before tempering. | | **Tempering** | **Temper immediately!** 150-315°C (300-600°F) for 1-2 hrs. | Typical: 175-205°C (350-400°F) for 60-61 HRC. Double temper recommended. | --- ## **Product Applications** O1 is a general-purpose cold work steel used across countless industries for tooling that requires a balance of hardness, toughness, and manufacturability. ### **Primary Applications:** 1. **Blanks, Forming, and Bending Dies:** For low to medium production runs on sheet metal. 2. **Cutting Tools:** Knives, shears, slitter blades, and hand tools (chisels, punches). 3. **Precision Gauges, Jigs, and Fixtures:** Where good stability and machinability are valued. 4. **Woodworking Tools:** Plane blades, carving tools, and router bits. 5. **Plastic Injection Molds & Cavities:** For prototype and low-volume molds. 6. **Thread Rolling Dies and Master Hubs.** 7. **General Machine Parts:** Bushings, cams, and wear plates requiring hardness. ### **Industry Usage:** - **Tool & Die Making** - **Metal Stamping & Fabrication** - **Cutlery & Hand Tool Manufacturing** - **Woodworking** - **General Machining & Maintenance** --- ## **International Standards & Cross-Reference** UNS T91501 / AISI O1 is recognized worldwide with direct equivalents in major standards. | Standard | Designation | Equivalent / Similar Grade | | :--- | :--- | :--- | | **UNS (USA)** | **T91501** | - | | **AISI/SAE (USA)** | **Type O1** | - | | **ASTM (USA)** | A681 | Grade O1 | | **Europe (EN)** | **1.2510** | 100MnCrW4 | | **Germany (DIN)** | **1.2510** | 100MnCrW4 | | **Japan (JIS)** | **SKS3** | - | | **UK (BS)** | **BO1** | - | | **Sweden (SS)** | **2140** | - | --- ## **Advantages & Considerations** ### **Advantages:** 1. **Superb Machinability & Grindability:** Low fabrication cost and fast lead times. 2. **Good Toughness:** Resists chipping and breaking better than harder, more brittle steels. 3. **Good Wear Resistance for Many Applications:** Adequate for a wide range of uses. 4. **Readily Available & Cost-Effective:** One of the most accessible and economical tool steels. 5. **Reliable & Forgiving Heat Treatment:** Less sensitive to exact parameters than many high-alloy steels. ### **Considerations:** 1. **Lower Wear Resistance than High-Alloy Steels:** Not suitable for highly abrasive applications or very long production runs. 2. **Moderate Dimensional Distortion:** More prone to warping during quenching than air-hardening grades (A2, D2). Requires careful quenching technique. 3. **Limited Hardenable Section Size:** Typically limited to sections under ~50mm (2") for full through-hardening. 4. **Not for Hot Work:** Lacks high-temperature (red) hardness. --- ## **Comparison with Other Common Grades** | | **O1 (Oil-Hardening)** | **A2 (Air-Hardening)** | **D2 (High-Carbon, High-Chromium)** | | :--- | :--- | :--- | :--- | | **Primary Quench Medium** | Oil | Air | Air | | **Distortion** | Moderate | **Very Low** | Very Low | | **Machinability** | **Excellent** | Good | Fair/Poor | | **Wear Resistance** | Good | Very Good | **Excellent** | | **Toughness** | **Very Good** | Good | Fair | | **Cost** | **Lowest** | Moderate | Higher | --- ## **Conclusion** **Oil-Hardening Cold Work Tool Steel (UNS T91501 / AISI O1)** remains a **fundamental and indispensable material** in the global toolmaking industry. Its unparalleled combination of **ease of fabrication, reliable performance, and cost-effectiveness** solidifies its role as the **ideal "first choice" for a vast array of general-purpose tooling**. While air-hardening steels may offer advantages in specific areas like minimal distortion or extreme wear resistance, O1's balanced properties and user-friendly nature make it the perfect workhorse steel for **prototypes, low-to-medium production tooling, and applications where ease of manufacture and toughness are priorities**. It is the benchmark against which other cold work steels are often compared for overall value and versatility. -:- For detailed product information, please contact sales. -: Oil-Hardening Cold Work Tool Steel (UNS T91501) Specification Dimensions Size： Diameter 20-1000 mm Length <6670 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. -: Oil-Hardening Cold Work Tool Steel (UNS T91501) Properties -:- For detailed product information, please contact sales. -:

Applications of Oil-Hardening Cold Work Tool Steel Flange (UNS T91501) -:- For detailed product information, please contact sales. -: Chemical Identifiers Oil-Hardening Cold Work Tool Steel Flange (UNS T91501) -:- For detailed product information, please contact sales. -:

Packing of Oil-Hardening Cold Work Tool Steel Flange (UNS T91501) -:- 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 3141 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