I-beam, as shown in the name, is a kind of steel whose cross section looks like the character “I”, and the slope of the upper flange surface and lower flange surface is generally 1:6, which making the flange thin outside while thick inside and causes big difference between the two main cross-section properties of I-beam.
It’s difficult to exert steel’s hardness in practical applications.
Although there is heavy I-beam in the steel market, the structure of I-beam has already determined its shortage of torsion resistance.
H-beam steel is widely used in steel structure buildings nowadays. It is quite different from I-beam.
The first is the flange difference and the second is that it has no inclination inside flange and the upper and lower surfaces are parallel.
The cross-section characteristic of H-beam steel is better than that of traditional I-beam, channel steel and angle steel.
H-beam steel is a more optimized steel with better distribution, stronger weight ratio and economic cross-section, which is named after the alphabet “H” because its cross-section shape is similar to this letter.
There is no slant between the two outside beams of H-beam steel, namely, they are straight.
This makes the welding of H-beam steel is simpler than that of I-beam.
H-beam steel has better mechanical properties of unit weight, which can save a lot of material and construction time.
The section of I beam steel is good at bearing direct pressure and tensile, but the section size is too narrow to resist twisting, which is quite opposite in terms of H-beam steel.
They both have advantages and disadvantages.
The differences and applications of H-beam steel and I-beam.
H-beam steel, whether ordinary or light, have a bigger difference between the two main inertia moments because the section sizes are relatively high, narrow.
Therefore, they generally can only be applied directly to the bending in its web plane of the component or its lattice stress components.
They are not suitable to be used in axial compression components or the bending component perpendicular to the web plane, which makes them very limited in the application scope.
H-beam steel is efficient economic cutting surface materials (similar to cold bending thin-wall steel, pressed steel plate, etc.).
Due to the reasonable section shape, they can make the steel function better and bear a higher load.
Different from the common I-beam, the flanges of H-beam steel are widened, and the inner and outer surfaces are usually parallel, which makes them strong in connecting high-strength bolts and other components.
With reasonable size series and complete models, they are easy to be designed and used(in addition to the I-beam steel for crane beams).
The flange of H-beam steel is of equal thickness, with rolling section, and a composite cross-section consisting of three plates welded together.
All I-beams are rolled section, having a 1:10 slope inside flanges because of the poor production process.
The rolling of H-beam steel is different from that of I-beam which uses only a set of the horizontal roll.
Due to its wide flange and no slope or little slope, it has to add a set of the vertical roll to roll H-beam steel at the same time, as a result, the rolling technology and equipment are more complicated than the ordinary rolling mill.
The maximum rolling height of H-beam steel in China is 800mm, and if higher height is required, it has to weld composite cross-sections.
In China, hot rolled H-beam steel national standard (GB/ t11263-1998) divides H-beam steel into three categories: narrow flange, wide flange and steel pile, whose codes are hz, hk and hu respectively.
The narrow flange H-beam is suitable for the beam or bending parts, while the broad flange H-beam steel and H-beam steel pile are suitable for axial compression parts or bending parts.
Comparing I-beam with H-beam steel under same weight, w, ix and iy of I-beam are not as good as H-beam steel.
I-beam is small in length, high in height and can only bear the force of one direction.
H-beam steel has a deep groove, large thickness and can withstand two directions of force.
As the demand of steel structure building grows, I-beam alone can not meet the demand because even thicken I-beams are unstable when used in load-bearing columns.
I-beam can only be used for beams while H-beam steel can be used for load-bearing columns.
H-beam steel is a kind of economical section steel with better section mechanical properties that I-beam.
It is so named because the shape of its cross-section is the same as the English letter “H”.
The flange of hot-rolled H-beam steel is wider than that of I-beam, large in lateral stiffness and strong in bending resistance.
Under the same specification, H-shape steel is lighter than I-beam.
The flange of I-beam is thick near the web while thin in the outsider. The flange of H-beam steel is equal in cross-sections.
HW, HM, HN, H are the general names of H-beam steel. H-beam steel is welding while HW, HM, HN are hot rolling.
HW refers to H-beam steel which basically has the same height and flange width, mainly used for steel core column in reinforced concrete frame column, also known as strong steel column and mainly used for column in steel structure.
HM refers to H-beam steel whose height and flange width ratio is roughly 1.33~~1.75; HM is mainly used in steel structure: as steel frame column or as frame beam in the frame structure bearing dynamic load, like device platform.
HN refers to H-beam steel who height and flange width ratio is greater than or equal to 2; HN is mainly used in beams, which is similar to the usage of I-beam.