. What’s the difference between I-beams and H-beams?

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It is often asked that since I-beams and H-beams have similar shapes, how should one choose between them in practical applications? Many people who have been in the construction industry for many years are unable to explain it in detail. Here is a detailed explanation for everyone: Many people think that I-beam is the term used in China, while H-beam is the term used abroad; actually, this understanding is incorrect. H-shaped steel and I-beam differ in shape, as shown in the figure below: I-beam. I-beams are mainly classified into ordinary I-beams, light-duty I-beams, and wide-flange I-beams. Based on the height ratio of the flange to the web, wide-flange I-beams are further divided into wide, medium, and narrow types. The first two types are produced in sizes 10–60, meaning their corresponding heights are 10–60 cm. At the same height, light I-beams have narrow flanges, thin webs, and low weight. Wide-flange I-beams, also known as H-beams, are characterized by parallel flanges with no slope on the inner side of these flanges. It belongs to the category of economic cross-section steel, and is rolled on a four-roller universal rolling mill; hence it is also known as a \"universal I-beam\". Standards have been established for regular I-beams and light I-beams. As the name suggests, an I-beam is a type of steel section with an “I”-shaped cross-section. The inner surfaces of its upper and lower flanges are inclined at a ratio of generally 1:6, which results in the flanges being thinner on the outside and thicker on the inside. As a result, the cross-sectional properties of the I-beam differ significantly in its two principal planes, making it difficult to utilize the strength characteristics of the steel in practical applications. Although thicker I-beams are now available on the market, the structure of I-beams inherently results in weak torsional strength. H-shaped steel is an efficient structural profile with an optimized distribution of cross-sectional area and a more favorable strength-to-weight ratio; it is named thus because its cross-section resembles the English letter “H”. Since all parts of the H-shaped steel are arranged at right angles, it possesses advantages such as strong bending resistance in all directions, simple construction, cost savings, and low structural weight, which has led to its widespread use. H-shaped steel is a widely used profile in modern steel structure buildings, and it has many differences compared to I-beams. First is the flange, and secondly, the inner surface of the flange has no inclination; its upper and lower surfaces are parallel. The cross-sectional properties of H-shaped steel are significantly superior to those of traditional I-beams, channel beams, and angle irons. The inner sides of the two outer edges of the H-shaped steel are straight, with no slope. This makes the welding of H-shaped steel simpler compared to I-shaped steel, it offers better mechanical properties per unit weight, and it allows for significant savings in materials and construction time. The I-beam section performs well under vertical loads and is resistant to tension, but its section dimensions, due to the narrow flanges, prevent it from withstanding torsion. H-shaped steel is the opposite; each has its own advantages and disadvantages. An intuitive display of the H-beam processing process: Followed, Follow, Replay, Share, Like, Stop watching. View more, Exit full screen, Switch to portrait mode, Exit full screen. Chemical equipment enthusiasts have followed this video; duration: 01:20/000:00/01:20. Switch to landscape mode, Continue playing. Progress bar: 0% played, 00:00/01:20. 01:20, Full screen. Playback speed: 0.5x, 0.75x, 1.0x, 1.5x, 2.0x. Your browser does not support the video tag. Continue watching. What’s the difference between I-beams and H-beams? View more. Reposted: What’s the difference between I-beams and H-beams? Chemical equipment enthusiasts have followed this video; Share, Like, Watching. It has also been shared on “See More”. Write your comments. Video details: Differences and applications of H-beams and I-beams. 1. Whether they are ordinary or lightweight, I-beams have relatively high and narrow cross-sectional dimensions, which results in significant differences in the inertial moments of their two main sections. Therefore, they can generally only be used in components that are subjected to bending forces within their web plane, or they can be used to form lattice-type structural elements. It is not suitable for axially compressed members or those that also experience bending perpendicular to the web plane, which limits its range of applications significantly. 　 2. H-shaped steel belongs to the category of high-efficiency and economical cross-sectional profiles (others include cold-formed thin-walled steel profiles and profiled steel sheets, etc.). Due to their rational cross-sectional shape, they enable steel to achieve higher efficiency and improve its load-bearing capacity. Unlike ordinary I-beams, the flanges of H-beams are widened, and their inner and outer surfaces are usually parallel, which facilitates connection using high-strength bolts and other components. Its sizes form a reasonable range with a full variety of models, making it easy to select for design purposes (except for I-beams used in crane beams). 3. The flanges of H-beams have uniform thickness; they can have a rolled cross-section or a composite cross-section formed by welding three plates together. I-beams all have rolled cross-sections, and due to poor manufacturing processes, there is a 1:10 slope on the inner edge of the flanges. The rolling of H-shaped steel differs from that of ordinary I-beams, which use only a set of horizontal rollers. Due to its wider flanges and lack of slope (or very slight slope), an additional set of vertical rollers is required for rolling as well; therefore, its rolling process and equipment are more complex than those of ordinary rolling mills. The maximum height of rolled H-beams that can be produced domestically is 800 mm; beyond this, only welded composite sections are possible. 4. I-beams have small side lengths and large heights, and can only withstand forces in one direction. 5. H-shaped steel has a deep groove and large thickness, allowing it to withstand forces in two directions. 6. With the evolving demands of steel structure construction, I-beams alone are insufficient; even thickened I-beams used as load-bearing columns are prone to instability. 7. I-beams can only be used for beams, while H-beams can be used for load-bearing columns in structures. 8. H-shaped steel is an economical type of section steel with superior mechanical properties compared to I-beams; it is named after its shape, which resembles the English letter “H”. The flanges of hot-rolled H-beams are wider than those of I-beams, offering greater lateral stiffness and stronger bending resistance. Under the same specifications, the theoretical weight of H-shaped steel is lower than that of I-shaped steel. 9. The I-beam flange has a variable cross-section, being thicker near the web and thinner on the outside ； The flanges of H-beams have equal cross-sections. 10. HW, HM, HN are general terms for H-shaped steel, which is welded ； HW, HM, HN are hot-rolled. 11. HW means that the height of the H-shaped steel is roughly equal to the width of its flanges ； It is mainly used for the steel-core columns in reinforced concrete frame structures, also known as reinforced steel columns ； In steel structures, it is mainly used for columns. 12. HM is the ratio of the height to the flange width of H-shaped steel, approximately ranging from 1.33 to 1.75 ； Primarily in steel structures: used as columns in steel frames, and as frame beams in frame structures subjected to dynamic loads. For example: device platform. 13. HN refers to H-shaped steel in which the ratio of height to flange width is 2 or greater, and it is mainly used for beams ； The uses of I-beams are similar to those of HN-type steel.