The calculator gives the theoretical weight of rolled metal from the section dimensions and the density of the grade. Choose the metal, product shape and grade and enter the sizes from the drawing: it shows the weight of one metre, the total weight of the batch, the length or number of pieces, and the surface area for estimating paint.
Formula
Weight equals the cross-section area multiplied by length and density: m = S × L × ρ. The area is calculated from the section geometry: π·d²/4 for a round bar, π·(D − t)·t for a pipe, length × width × thickness for a sheet. For rectangular tube and angles the corner radii are taken into account as in GOST 30245 and GOST 8509.
For rebar, I-beams and channels the calculator takes the weight per metre from the tables of GOST 34028, GOST 8239 and GOST 8240. If the section is not to GOST, choose “Custom size” and enter the height, flange width and thicknesses.
Metal densities
Carbon steel (St3, 09G2S, 20, 45): 7.85 g/cm³Stainless steel (12Kh18N10T, AISI 304, AISI 321): 7.9 g/cm³, AISI 316: 8.0 g/cm³Aluminium and its alloys: 2.64–2.85 g/cm³ depending on the gradeCopper: 8.94 g/cm³, brass: 8.44–8.78 g/cm³, bronze: 7.5–8.9 g/cm³Titanium: 4.4–4.55 g/cm³
The real weight differs from the theoretical one because of dimensional tolerances: pipes and sheets are usually rolled to a minus or plus tolerance. For ordering and logistics the difference is a few percent. The manager will give the exact weight of a batch from the manufacturer’s certificate.