I-Beam double flanged - this type of products include hot rolled double flanged beams (I-beams), produced according to GOST 535-88. I-Beams are separated into several types:

I-Beams with parallel flanges

• normal (20B, and etc.)
• wide flanges (20Sh and etc.)
• column (20K and etc.)

The assortment of I-beams with parallel flanges can correspond to either GOST 26020-83, or its own unique technical specification STO ASCHM 20-93 of Nizhniy Tagil metallurgical plant, that is the main supplier of I-Beams in Russia.

I-Beams with sloping edges of flanges

• normal (edge slope 6-12%) GOST 8239-89 (№10, 12, 16 and etc.)

Assortment of such I-Beams corresponds to GOST 8239-89. Special (M and C):

• M - for hanging rails (edge slope not more than 12%): 18M, 24M, 30M and etc.;
• C - for reinforcement of mine shafts (edge slope not more than 16%): 14S, 20S and etc.

Assortment of such double flanged beams corresponds to GOST 19425-74. The number of the I-beam is its conventional size (height) in cm.

Example
normal I-beam 30B1 - h (height of the beam)=296mm

normal I-beam 30B2-h=299mm. The rest of the dimensions: width of the flanges, thickness of the walls and etc.  is made according to GOST.

The minimum size of the I-beam is 10, maximum - 100 (100B4). All, that is above or below this specification can only be made by special order to factory-producer. The size of the I-beam - is the length between the outer flange edges. Double flanged beams are used in large-panel, industrial and civilian construction of floors, column metal constructs, bridges, supports and hanging rails.