ASTM A724 Carbon Steel Seamless tube, Grade C

ASTM A724 Carbon Steel Seamless tube, Grade C Product Information -:- For detailed product information, please contact sales. -: ASTM A724 Carbon Steel Seamless tube, Grade C Synonyms -:- For detailed product information, please contact sales. -:

ASTM A724 Carbon Steel, Grade C Product Information -:- For detailed product information, please contact sales. -: # **Product Introduction: ASTM A724 Grade C Carbon Steel Plate for Ultra-High-Strength Layered Pressure Vessels** **ASTM A724 Grade C** is the highest strength grade within the ASTM A724 specification, representing a premium **quenched-and-tempered carbon-manganese steel** engineered exclusively for the most demanding **welded multilayer pressure vessel** applications. This grade is designed to be **split into multiple layers** during fabrication to construct vessels with extreme wall thicknesses for ultra-high-pressure service. **Grade C delivers a minimum yield strength of 85 ksi (585 MPa)**, offering the maximum strength-to-weight efficiency in carbon steel for layered construction. It is the material of choice for the most advanced high-pressure reactors in chemical synthesis, gas processing, and hydrogen technologies where minimizing wall thickness and vessel weight is paramount for economic and engineering feasibility. --- ## **International Standard & Key Specifications** * **Primary Standard:** **ASTM A724 / A724M** - Standard Specification for Pressure Vessel Plates, Carbon-Manganese-Silicon Steel, for Quenched-and-Tempered Layered Pressure Vessels. * **Critical Quality Assurance:** The standard mandates **Simulated Post-Weld Heat Treatment (SPWHT)** testing. Plates are certified to meet all mechanical property requirements **after** undergoing a thermal cycle that replicates the vessel's fabrication heat treatment. * **Mandatory Metallurgical Condition:** Supplied exclusively in the **quenched-and-tempered (Q&T) condition** to develop a uniform, fine-grained tempered martensitic microstructure capable of withstanding the splitting process and high service stresses. * **ASME Code Equivalent:** **SA-724 / SA-724M** in ASME Boiler and Pressure Vessel Code, Section II, Part A, for the fabrication of ASME-stamped pressure equipment. --- ## **Chemical Composition (Weight %, max unless range is specified)** The chemistry for Grade C is precisely balanced to achieve exceptional hardenability for the 85 ksi strength level while maintaining sufficient toughness and weldability. It typically features controlled additions of microalloying elements. | Element | Composition (%) | Role/Note | | :--- | :--- | :--- | | **Carbon (C)** | 0.15 - 0.21 | Primary contributor to strength and hardenability; carefully controlled at the upper limit of the range. | | **Manganese (Mn)** | **1.30 - 1.60** | **Elevated level is critical.** Significantly increases hardenability and solid-solution strength to achieve the 85 ksi yield strength. | | **Phosphorus (P)** | 0.025 | Impurity, kept at a very low maximum to preserve notch toughness. | | **Sulfur (S)** | 0.025 | Impurity, minimized to ensure good through-thickness properties and weldability. | | **Silicon (Si)** | 0.15 - 0.50 | Deoxidizer and solid solution strengthener. | | **Nickel (Ni)** | 0.40 (optional) | Often added to enhance low-temperature toughness and improve hardenability without increasing carbon equivalent drastically. | | **Chromium (Cr)** | 0.25 | Residual/allowable element, limited to control hardenability. | | **Molybdenum (Mo)** | 0.08 | Residual/allowable; may be present for enhanced strength. | | **Vanadium (V)** | 0.05 | Common microalloy addition for grain refinement and precipitation strengthening. | | **Columbium (Cb/Nb)** | 0.05 | May be used for grain refinement and precipitation hardening. | **Note:** The exact microalloying strategy (V, Cb) is at the steelmaker's discretion to achieve the required mechanical properties. --- ## **Typical Physical & Mechanical Properties** All properties are guaranteed for the Q&T plate **after** the mandatory simulated PWHT cycle. | Property | Value / Description | | :--- | :--- | | **Tensile Strength** | **690 - 860 MPa (100,000 - 125,000 psi)** | | **Yield Strength (min)** | **585 MPa (85,000 psi)** | | **Elongation in 2-in (50 mm) (min)** | 16% | | **Reduction of Area (min)** | 35% | | **Modulus of Elasticity** | ~200 GPa (29 x 10⁶ psi) | | **Density** | ~7.85 g/cm³ (0.284 lb/in³) | | **Charpy V-Notch Impact Toughness** | **Test Temperature:** **-30°F (-34°C)**. **Minimum Avg. for 3 Specimens:** **20 ft·lbf (27 J)**. **Minimum Single Value:** 15 ft·lbf (20 J). | | **Simulated PWHT Requirement:** | Plates are tested after exposure to a thermal cycle simulating fabrication heat treatment (e.g., 1150°F ± 25°F / 620°C ± 14°C), ensuring properties remain stable in the finished vessel. | --- ## **Product Applications** ASTM A724 Grade C is specified for the most critical, highest-pressure multilayer vessels where material performance limits are pushed to enable next-generation process efficiency and scale. **Primary Ultra-High-Pressure Applications:** 1. **Advanced Chemical Synthesis:** * **Mega-Capacity Ammonia Synthesis Reactors** in modern, single-train fertilizer plants operating at the highest pressures (>200 bar) for optimal conversion efficiency. * **Methanol Synthesis Loops** in large-scale gas-to-chemicals complexes. * **High-Pressure Polyolefin Reactors** (e.g., for LLDPE, HDPE). 2. **Hydrogen Economy Infrastructure:** * **Centralized High-Pressure Hydrogen Storage Vessels** (>500 bar) for refueling stations and grid balancing. * **Hydrogen Transport Modules (Tube Trailers)** designed for maximum gas capacity. * **Components within Advanced Electrolysis Systems.** 3. **Oil & Gas and Energy Transition:** * **Hydrocracking Reactors** for processing heavier, more difficult feedstocks. * **Vessels for Carbon Capture, Utilization, and Storage (CCUS)**, handling high-pressure CO2 streams. * **Process vessels in Coal-to-Liquids (CTL) and Gas-to-Liquids (GTL) plants.** **Rationale for Grade C in Layered Construction:** * **Maximizes Design Pressure:** The 85 ksi yield strength allows for the highest possible pressure ratings within the layered vessel paradigm. * **Minimizes Vessel Weight and Footprint:** Critical for reducing structural support costs, transportation logistics, and overall plant layout. * **Enables Economical Mega-Scale Designs:** Makes single, large-volume reactors technically and economically viable versus multiple smaller units. --- ## **Advantages and Critical Fabrication Considerations** * **Advantages:** * **Maximum Strength in Class:** Provides the highest yield strength (85 ksi) available in the A724 specification for carbon steel layered vessels. * **Superior Strength-to-Weight Ratio:** Enables the most material-efficient and compact high-pressure vessel designs. * **Certified Property Stability:** The SPWHT guarantee is non-negotiable for reliable high-pressure design. * **Critical Fabrication & Welding Considerations:** * **Elite Fabrication Expertise Required:** Use is restricted to fabricators with proven, specialized capability in multilayer vessel technology and strict quality management systems. * **Extreme Welding Control:** **Ultra-low-hydrogen welding procedures are mandatory.** Welding consumables and procedures must be meticulously selected and qualified to match the high strength and maintain toughness in the heat-affected zone (HAZ). Stringent control of preheat, interpass temperature, and heat input is essential. * **Precision PWHT Execution:** The vessel's actual PWHT cycle must be a near-perfect match to the plate's simulation parameters. Deviations risk altering the tempered microstructure and properties. * **Comprehensive NDT:** Requires 100% ultrasonic testing (UT) of plates and all weld seams. Advanced NDT techniques may be specified. **In summary, ASTM A724 Grade C is the pinnacle carbon steel for multilayer pressure vessel construction, offering an 85 ksi minimum yield strength for the most severe high-pressure services. Its use represents a commitment to advanced engineering, requiring specialized fabrication and utmost quality control to safely harness its exceptional strength for groundbreaking applications in the chemical, energy, and hydrogen sectors.** -:- For detailed product information, please contact sales. -: ASTM A724 Carbon Steel, Grade C Specification Dimensions Size： Diameter 20-1000 mm Length <4520 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. -: ASTM A724 Carbon Steel, Grade C Properties -:- For detailed product information, please contact sales. -:

Applications of ASTM A724 Carbon Steel Seamless tube, Grade C -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A724 Carbon Steel Seamless tube, Grade C -:- For detailed product information, please contact sales. -:

Packing of ASTM A724 Carbon Steel Seamless tube, Grade C -:- 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 Seamless tube 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 991 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