W24x370 is an American standard H-beam specification, named after its nominal weight of about 370 pounds per foot, which is equivalent to about 550 kilograms per meter. The W indicates a wide flange shape, and 24 is the nominal depth in inches. This heavy section is used in structural projects that require high strength and large load-bearing capacity, such as high-rise buildings, bridges, and heavy equipment foundations.
What Is a W24x370 Wide Flange Beam?
In the ASTM A6 designation system, W shapes are wide flange sections with parallel flange faces, used as beams and columns in structural steel frames. The designation W24x370 identifies a W shape with a nominal depth of 24 inches and a nominal weight of 370 pounds per foot. Sections of this weight class are among the heaviest standard wide flange shapes and are rolled to the dimensional and tolerance requirements of ASTM A6. They are produced in structural steel grades specified for building and bridge construction, and the section properties are published in standard steel shape tables for design use.
Typical Material Grades and Properties
Common manufacturing materials for W24x370 include high-strength low-alloy steels such as A572 Grade 50, which provide good strength and toughness. For A572 Grade 50 material, the yield strength is at least 345 MPa (50 ksi), which is very suitable for large-load applications. The tensile strength is at least 450 MPa (65 ksi), and the elongation is typically at least 18-21% depending on the test gauge length, ensuring good ductility of the material. For building frames, the grade A992 is often specified instead, with a minimum yield strength of 50 ksi (345 MPa), a maximum yield of 65 ksi (450 MPa), and a yield-to-tensile ratio capped at 0.85 to support ductile seismic behavior. The grade should be selected according to the governing design standard and the project requirements.
Applications
W24x370 sections are suitable for frame columns and beams of high-rise buildings and large industrial plants, particularly in earthquake-prone areas, where the large section provides excellent strength and stiffness. In bridge construction, the section is used as a key material for bridge main beams or piers, supporting larger spans and weights. Other large steel structure projects include crane tracks, offshore platforms, and power transmission towers, where heavy loads and long spans require deep, heavy wide flange sections. The high load-carrying capacity of the section reduces the number of members required and simplifies connections in heavily loaded structures.
Fabrication and Installation
W24x370 is easy to cut, weld, and drill, and can be customized according to construction requirements. Because of the large weight of the section, special attention must be paid to the use of appropriate equipment and techniques during transportation and hoisting to ensure safety. Welding should follow qualified procedures appropriate to the grade and thickness of the flange and web, with preheat and heat input controlled to avoid cracking in thick sections. The heavy weight per unit length also affects shipping, handling, and erection planning, and the section is typically supplied with surface treatments such as bare mill finish, galvanizing, or painting as required by the project.
Selection Considerations
When selecting W24x370, the designer should verify the section properties from the governing shape tables, the material grade and its strength guarantee, and the design loads. For seismic design, a grade with controlled yield-to-tensile ratio such as A992 is preferred, while A572 Grade 50 is commonly used where the project is designed to that specification. The availability of very heavy sections may be limited by the rolling schedule of the producing mill, so lead time and minimum order quantities should be confirmed early in the procurement process.
Frequently Asked Questions
What does W24x370 mean? W indicates a wide flange shape, 24 is the nominal depth in inches, and 370 is the nominal weight in pounds per foot, equivalent to about 550 kilograms per meter.
What material is W24x370 typically made of? Common materials include high-strength low-alloy steels such as A572 Grade 50, with a minimum yield strength of 50 ksi (345 MPa) and a minimum tensile strength of 65 ksi (450 MPa). Grade A992 is often specified for building frames.
What are the applications of W24x370? It is used for frame columns and beams of high-rise buildings and large industrial plants, bridge main beams and piers, crane tracks, offshore platforms, and power transmission towers, where high strength and large load-bearing capacity are required.
Can W24x370 be welded? Yes, it can be cut, welded, and drilled, and customized according to construction requirements. Welding should follow qualified procedures appropriate to the grade and thickness of the section.
What is the difference between W shapes and H beams? In the US system, W shapes are wide flange sections with parallel flange faces defined by ASTM A6. Similar sections in other systems include the H beam series, and the choice depends on the design standard and the section properties required.
What surface treatments are available? Sections are commonly supplied in bare mill finish, black, galvanized, coated, or painted condition, depending on the corrosion protection requirements of the project.