Calculation formula of theoretical weight of hexagonal bar
According to the dimension, shape, weight and allowable deviation of hot rolled steel bar (GB / T702-2008), the distance between the opposite sides of hot-rolled hexagons is 8mm ~ 70mm, which is generally delivered according to the actual weight or the theoretical weight in the market.
Calculation formula for theoretical weight of hexagonal bar
Where W is the theoretical weight in kg / M and D is the distance from the opposite side in mm.
Calculation example of theoretical weight of hexagonal bar
For example, calculate the theoretical weight of hexagonal bar with the opposite side distance of 50 mm, i.e
Cross section diagram of hexagonal bar
Actual drawing of hexagonal bar
Theoretical weight table of hexagonal bar (GB / T 702-2008)
| Specifications (mm) | Theoretical weight (kg/m) |
| 8 | 0.435 |
| 9 | 0.551 |
| 10 | 0.680 |
| 11 | 0.823 |
| 12 | 0.979 |
| 13 | 1.05 |
| 14 | 1.33 |
| 15 | 1.53 |
| 16 | 1.74 |
| 17 | 1.96 |
| 18 | 2.20 |
| 19 | 2.45 |
| 20 | 2.72 |
| 21 | 3.00 |
| 22 | 3.29 |
| 23 | 3.60 |
| 24 | 3.92 |
| 25 | 4.25 |
| 26 | 4.60 |
| 27 | 4.96 |
| 28 | 5.33 |
| 30 | 6.12 |
| 32 | 6.96 |
| 34 | 7.86 |
| 36 | 8.81 |
| 38 | 9.82 |
| 40 | 10.88 |
| 42 | 11.99 |
| 45 | 13.77 |
| 48 | 15.66 |
| 50 | 17.00 |
| 53 | 19.10 |
| 56 | 21.32 |
| 58 | 22.87 |
| 60 | 24.50 |
| 63 | 26.98 |
| 65 | 28.72 |
| 68 | 31.43 |
| 70 | 33.30 |
Calculation of the Theoretical Weight of Steel Chart
The unit for the calculated theoretical weight of steel is kilo grams (kg). The fundamental equation is as follows:
- W (weight in kg ) = F (cross section area in mm² )× L (length in m )×ρ(density ing/cm³ )× 1/1000
The density of stainless steel is: 7.85g/cm³, the equations for calculating the theoretical weight of different kinds of steel are as follows:
| Name (unit) | Calculation equation | Meaning of symbol | Calculation example |
| Round steel Bull rod (kg/m) | W= 0.006165 ×d² | d = diameter mm | Round steel with diameter of 100 mm, calculate the weight per m. Weight per m= 0.006165 ×1002= 61.65kg |
| Deformed steel bar (kg/m) | W= 0.00617 ×d² | d= cross-section diameter mm | Deformed steel bar with a cross-section diameter of 12 mm，calculate the weight per m. Weight per m = 0.00617 ×12 2 = 0.89kg |
|
Square bar (kg/m) |
W= 0.00785 ×a² | a= width of the edge, mm | Square bar with width of the edge of 20 mm, calculate weight per m.Weight per m = 0.00785 ×202= 3.14kg |
|
Flat steel (kg/m) |
W= 0.00785 ×b ×d |
b= width of the edge, mm d= thickness, mm |
Flat steel with width of the edge of 40 mm, and thickness of 5mm, calculate weight per m. Weight per m = 0.00785 ×40 ×5= 1.57kg |
| Hexagonal bar (kg/m) | W= 0.006798 ×s² | s= distance between opposite edges, mm | Hexagonal bar with distance between opposite edges of 50 mm, calculate weight per m. Weight per m = 0.006798 ×502= 17kg |
|
Octagonal steel (kg/m) |
W= 0.0065 ×s² | s= distance between opposite edges, mm | Octagonal steel with distance between opposite edges of 80 mm, calculate weight per m. Weight per m = 0.0065 ×802= 41.62kg |
| Equal-Angle Iron (kg/m) | W= 0.00785 ×[d (2b – d )+0.215 (R² – 2r² )] |
b= width of the edge d= thickness of the edge R= radius of inner arc r= radius of end arc |
Calculate weight per m of an equal-angle bar with size of 20 mm×4mm. R of the 4mm×20 mmequal-angle bar is 3.5, and r is 1.2, as can be found in the catalogue of metallurgical products, then, weight per m = 0.00785 ×[4 ×(2 ×20 – 4 )+0.215 ×(3.52 – 2 ×1.2 2 )]= 1.15kg |
| Angle Iron with unequal legs (kg/m) | W= 0.00785 ×[d (B+b – d )+0.215 (R² – 2 r² )] |
B= width of the longer edge b= width of the shorter edge d= thickness f the edge R= radius of the inner arc r= radius of the end arc |
Calculate the weight per m of an angle steel with unequal legs with size of 30 mm×20mm×4mm. The R of an unequal angle with size of 30 ×20 ×4 is 3.5, r is 1.2，as can be found in the catalogue of metallurgical products, then weight per m = 0.00785 ×[4 ×(30+20 – 4 )+0.215 ×(3.52 – 2 ×1.2 2 )]= 1.46kg |
| Channel steel (kg/m) | W=0.00785 ×[hd+2t (b – d )+0.349 (R² – r² )] |
h= height b= length of the leg d= thickness of the waist t= average thickness of legs R= radius of inner arc r= radius of end arc |
Calculate weight per mof a channel steel of size of 80 mm×43mm×5mm. The t of this channel steel is 8, R is 8, and r is 4, as can be found in the catalogue of metallurgical products, then, weight per m = 0.00785 ×[80 ×5+2 ×8 ×(43 – 5 )+0.349 ×(82–4 2 )]= 8.04kg |
|
Steel I-beam (kg/m) |
W= 0.00785 ×[hd+2t (b – d )+0.615 (R² – r² )] |
h= height b= length of legs d= thickness of waist t= average thickness of legs R= radius of inner arc r= radius of end arc |
Calculate weight per m of a steel I-beam of a size of 250 mm×118mm×10mm.Thetofthis I-beam is 13, R is 10, and r is 5 , as can be found in the manual of metallurgical materials, then, weight per m =0.00785 ×[250 ×10+2 ×13 ×(118 –10 )+0.615 ×(102 –5 2 )]= 42.03kg |
| Steel plate (kg/m²) | W= 7.85 ×d | d= thickness | steel plate of a thickness of 4mm, calculate weight per m². Weight per m² = 7.85 ×4= 31.4kg |
|
Steel Pipe (including seamless steel pipe and welded steel pipe)(kg/m) |
W= 0.02466 ×S (D – S ) |
D= outer diameter S= thickness of the wall |
Seamless steel pipe of an outer diameter of 60 mm and thickness of the wall of 4mm,calculate weight per m. Weight per m = 0.02466 ×4 ×(60 –4 )= 5.52kg |
Source: China Steel Bar Manufacturer – Yaang Pipe Industry Co., Limited (www.epowermetals.com)
(Yaang Pipe Industry is a leading manufacturer and supplier of nickel alloy and stainless steel products, including Super Duplex Stainless Steel Flanges, Stainless Steel Flanges, Stainless Steel Pipe Fittings, Stainless Steel Pipe. Yaang products are widely used in Shipbuilding, Nuclear power, Marine engineering, Petroleum, Chemical, Mining, Sewage treatment, Natural gas and Pressure vessels and other industries.)
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