What Are Mild Steel Plates or MS Plates?
Before discussing how to calculate the weight of MS plates, let us first understand what they are.
Mild steel plates are flat plates made from low-carbon steel. The term MS normally means mild steel. An MS plate is not automatically galvanized; galvanizing is a separate zinc-coating process applied when additional corrosion protection is required.
Mild steel has a low carbon content (about 0.05-0.25%), making it ductile and easy to form. Mild steel is itself a type of carbon steel. Its strength and chemical limits depend on the selected grade and product standard, so one general tensile-strength value should not be applied to every MS plate.
Because ordinary mild steel can rust when it is exposed to moisture and oxygen, suitable paint, galvanizing, another protective system, or a corrosion allowance may be required. Its strength also changes with temperature and can decrease significantly at elevated temperatures.
These MS plates come in a number of shapes and sizes that may be used through processes including rolling and bending. They can also be cut and drilled to fit the needs of the work.
The following characteristics make mild steel plate useful for many applications:
- Due to its high degree of ductility, it may deform without breaking.
- It has a high level of toughness.
- It can be cut, drilled, formed, and welded using suitable procedures.
- It is widely available in many grades, widths, lengths, and thicknesses.
- It provides a practical combination of strength, toughness, fabrication, and cost.
The most typical uses for mild steel plates are as follows:
- Building projects
- Commercial structures
- Housing projects
- Base plates, connection plates, stiffeners, girders, tanks, equipment frames, and general fabrication
How to Calculate the Weight of MS Plates
Here, we provide the method to calculate the weight of mild steel plates (MS plates) with different dimensions and sizes.
Basically, if we want to obtain the weight of anything, we multiply its density by volume. In the case of MS plates, we usually express the weight of plates per m2 of plate area.
Mass = density × length × width × thickness
A commonly used nominal density for carbon steel is:
ρ = 7850 kg/m3 = 7.85 g/cm3 = 490 lb/ft3
Although people usually call the result “weight,” formulas in kilograms calculate mass. The word weight is retained here because it is the normal fabrication and estimating term.
Metric Formula
When length and width are in metres and thickness is in millimetres:
Plate weight (kg) = L (m) × B (m) × t (mm) × 7.85
For one square metre of plate:
Plate weight (kg/m2) = t (mm) × 7.85
Imperial Formula
When length and width are in feet and thickness is in inches:
Plate weight (lb) = L (ft) × B (ft) × t (in.) × 40.833
For one square foot of plate:
Plate weight (lb/ft2) = t (in.) × 40.833
MS Plate Weight Calculator
Enter the nominal dimensions and the number of plates. The calculator updates while you type, and the Calculate button performs the same calculation when pressed.
| Weight per unit area | 47.1 kg/m² |
|---|---|
| One plate | 282.6 kg |
| Total for 1 plate | 282.6 kg |
MS Plate Weight Chart
The values below use the nominal carbon-steel density of 7850 kg/m3.
| Plate thickness | Weight (kg/m2) | Weight (lb/ft2) | Weight of 2 m × 1 m plate |
|---|---|---|---|
| 3 mm | 23.55 | 4.82 | 47.10 kg |
| 4 mm | 31.40 | 6.43 | 62.80 kg |
| 5 mm | 39.25 | 8.04 | 78.50 kg |
| 6 mm | 47.10 | 9.65 | 94.20 kg |
| 8 mm | 62.80 | 12.86 | 125.60 kg |
| 10 mm | 78.50 | 16.08 | 157.00 kg |
| 12 mm | 94.20 | 19.29 | 188.40 kg |
| 12.5 mm | 98.13 | 20.10 | 196.25 kg |
| 16 mm | 125.60 | 25.72 | 251.20 kg |
| 20 mm | 157.00 | 32.15 | 314.00 kg |
| 25 mm | 196.25 | 40.19 | 392.50 kg |
| 32 mm | 251.20 | 51.44 | 502.40 kg |
| 40 mm | 314.00 | 64.30 | 628.00 kg |
| 50 mm | 392.50 | 80.38 | 785.00 kg |
MS Plate Weight Calculation Examples
Example 1: Weight per Square Metre
Mild steel plates exist in multiple thicknesses such as 6 mm, 8 mm, 10 mm, and 12.5 mm. Based on the previous equation, we can calculate the weight per unit area for various thicknesses of plates.
For t = 6 mm, the weight of the MS plate = 7.85 × 6 = 47.1 kg/m2.
For t = 8 mm, the weight of the MS plate = 7.85 × 8 = 62.8 kg/m2.
For t = 10 mm, the weight of the MS plate = 7.85 × 10 = 78.5 kg/m2, and so on for various thicknesses of plates.
The previous calculations assume the area of the plate is 1 m × 1 m.
Example 2: Total Weight of a Rectangular Plate
In some cases, we would like to calculate the total weight of MS plates. Instead of assuming the area as 1 m × 1 m, we multiply by the total area of the plate.
For example, the weight of a 2 m × 3 m MS plate with a thickness of 6 mm will be equal to:
Weight = 47.1 kg/m2 × 2 m × 3 m = 282.6 kg
Example 3: Imperial Plate
For an 8 ft × 4 ft plate with a thickness of 1/4 in.:
Weight = 8 × 4 × 0.25 × 40.833 = 326.7 lb
How to Allow for Holes and Cutouts
For a plate containing holes, first calculate the gross plate weight. Then calculate the weight of the removed volume using the same density and subtract it.
For a circular hole of diameter d:
Hole area = πd2 / 4
Net plate weight = gross plate weight – weight of all holes and cutouts
This correction is useful for large openings. For small bolt holes, estimators may use gross theoretical weight depending on the purpose and project practice.
Theoretical Weight Versus Actual Weight
The formula gives a theoretical weight based on nominal dimensions and nominal density. The actual delivered weight may differ because of permitted thickness and dimensional tolerances, rolling variation, scale, coatings, and the exact steel chemistry. Use certified mill data or an actual scale where shipping, lifting, invoicing, or load control requires the measured weight.
References
- AISC, Code of Standard Practice reference using 490 lb/ft3 (7850 kg/m3) for steel.
- AISC, Steel Construction Manual, 15th Edition.
Read Also:
Weight Calculation of Rectangular Steel Bars (Solid + Hollow)