Brass C36000 Rectangular Tube Weight
Mass per metre and per foot for brass c36000 rectangular tube at 8,500 kg/m³ (ASTM B16 (UNS C36000, free-cutting)). Every figure is for the section as drawn. A 6 m length of this size weighs 28.8 kg (64.4 lb per 20 ft).
At the reference dimensions (a = 60 mm, b = 40 mm, t = 3 mm) this section has a cross-sectional area of 564.0 mm², giving 4.794 kg/m (3.221 lb/ft). Against carbon steel's 7,850 kg/m³ that is +8.3 % — the same section in steel would be 4.427 kg/m.
Rectangular Tube — formula and derivation
Area of a rectangular tube
A = a·b − (a − 2t)(b − 2t)
A = a·b − (a − 2t)(b − 2t), which expands to A = 2t(a + b) − 4t²
Worked through with the default dimensions:
A = a·b − (a − 2t)(b − 2t)Outer = 60 × 40 = 2400.0 mm²Inner = 54.0 × 34.0 = 1836.0 mm²A = 2400.0 − 1836.0A = 564.0 mm²
- a
- Depth
- b
- Width
- t
- Wall thickness
Weight follows from the area with no further geometry: m = A × 10⁻⁶ × ρ, where A is in mm², ρ in kg/m³ and m in kg/m. At 8,500 kg/m³ that is 4.7940 kg/m for the reference size above.
Brass rectangular tube — size series
| Depth | 1.5 | 2.0 | 3.0 | 4.0 | 5.0 | 6.0 |
|---|---|---|---|---|---|---|
| 20 mm | 0.688 kg/m · 0.463 lb/ft | 0.884 kg/m · 0.594 lb/ft | 1.224 kg/m · 0.822 lb/ft | 1.496 kg/m · 1.005 lb/ft | 1.700 kg/m · 1.142 lb/ft | 1.836 kg/m · 1.234 lb/ft |
| 25 mm | 0.880 kg/m · 0.591 lb/ft | 1.139 kg/m · 0.765 lb/ft | 1.606 kg/m · 1.080 lb/ft | 2.006 kg/m · 1.348 lb/ft | 2.337 kg/m · 1.571 lb/ft | 2.601 kg/m · 1.748 lb/ft |
| 30 mm | 1.071 kg/m · 0.720 lb/ft | 1.394 kg/m · 0.937 lb/ft | 1.989 kg/m · 1.337 lb/ft | 2.516 kg/m · 1.691 lb/ft | 2.975 kg/m · 1.999 lb/ft | 3.366 kg/m · 2.262 lb/ft |
| 40 mm | 1.453 kg/m · 0.977 lb/ft | 1.904 kg/m · 1.279 lb/ft | 2.754 kg/m · 1.851 lb/ft | 3.536 kg/m · 2.376 lb/ft | 4.250 kg/m · 2.856 lb/ft | 4.896 kg/m · 3.290 lb/ft |
| 50 mm | 1.836 kg/m · 1.234 lb/ft | 2.414 kg/m · 1.622 lb/ft | 3.519 kg/m · 2.365 lb/ft | 4.556 kg/m · 3.061 lb/ft | 5.525 kg/m · 3.713 lb/ft | 6.426 kg/m · 4.318 lb/ft |
| 60 mm | 2.219 kg/m · 1.491 lb/ft | 2.924 kg/m · 1.965 lb/ft | 4.284 kg/m · 2.879 lb/ft | 5.576 kg/m · 3.747 lb/ft | 6.800 kg/m · 4.569 lb/ft | 7.956 kg/m · 5.346 lb/ft |
| 80 mm | 2.983 kg/m · 2.005 lb/ft | 3.944 kg/m · 2.650 lb/ft | 5.814 kg/m · 3.907 lb/ft | 7.616 kg/m · 5.118 lb/ft | 9.350 kg/m · 6.283 lb/ft | 11.016 kg/m · 7.402 lb/ft |
| 100 mm | 3.748 kg/m · 2.519 lb/ft | 4.964 kg/m · 3.336 lb/ft | 7.344 kg/m · 4.935 lb/ft | 9.656 kg/m · 6.489 lb/ft | 11.900 kg/m · 7.996 lb/ft | 14.076 kg/m · 9.459 lb/ft |
| 120 mm | 4.513 kg/m · 3.033 lb/ft | 5.984 kg/m · 4.021 lb/ft | 8.874 kg/m · 5.963 lb/ft | 11.696 kg/m · 7.859 lb/ft | 14.450 kg/m · 9.710 lb/ft | 17.136 kg/m · 11.515 lb/ft |
| 150 mm | 5.661 kg/m · 3.804 lb/ft | 7.514 kg/m · 5.049 lb/ft | 11.169 kg/m · 7.505 lb/ft | 14.756 kg/m · 9.916 lb/ft | 18.275 kg/m · 12.280 lb/ft | 21.726 kg/m · 14.599 lb/ft |
| 200 mm | 7.574 kg/m · 5.089 lb/ft | 10.064 kg/m · 6.763 lb/ft | 14.994 kg/m · 10.076 lb/ft | 19.856 kg/m · 13.343 lb/ft | 24.650 kg/m · 16.564 lb/ft | 29.376 kg/m · 19.740 lb/ft |
Rows: depth (mm). Columns: wall thickness (mm). Computed for Brass C36000 at 8500 kg/m³.
| Depth | 1.5 | 2.0 | 3.0 | 4.0 | 5.0 | 6.0 |
|---|---|---|---|---|---|---|
| 20 mm | 81.0 | 104.0 | 144.0 | 176.0 | 200.0 | 216.0 |
| 25 mm | 103.5 | 134.0 | 189.0 | 236.0 | 275.0 | 306.0 |
| 30 mm | 126.0 | 164.0 | 234.0 | 296.0 | 350.0 | 396.0 |
| 40 mm | 171.0 | 224.0 | 324.0 | 416.0 | 500.0 | 576.0 |
| 50 mm | 216.0 | 284.0 | 414.0 | 536.0 | 650.0 | 756.0 |
| 60 mm | 261.0 | 344.0 | 504.0 | 656.0 | 800.0 | 936.0 |
| 80 mm | 351.0 | 464.0 | 684.0 | 896.0 | 1,100.0 | 1,296.0 |
| 100 mm | 441.0 | 584.0 | 864.0 | 1,136.0 | 1,400.0 | 1,656.0 |
| 120 mm | 531.0 | 704.0 | 1,044.0 | 1,376.0 | 1,700.0 | 2,016.0 |
| 150 mm | 666.0 | 884.0 | 1,314.0 | 1,736.0 | 2,150.0 | 2,556.0 |
| 200 mm | 891.0 | 1,184.0 | 1,764.0 | 2,336.0 | 2,900.0 | 3,456.0 |
Area is a property of the geometry alone, so this table is the same for every material. It is what you enter into a stress calculation; the mass table is what you enter into an order.
Each row is one nominal size. Because the area is computed from your dimensions rather than read from a mill table, a non-standard size is just as accurate — put it into the calculator above rather than interpolating between rows.
The same rectangular tube in every material
Geometry is fixed and only density changes, so this table is the whole material-selection question in one view. Brass C36000 is highlighted. The percentage column is against carbon steel, which is the figure most quotations are built on.
| Material | Density kg/m³ | lb/in³ | Mass / length kg/m | lb/ft | vs carbon steel |
|---|---|---|---|---|---|
| Carbon Steel | 7,850 | 0.2836 | 4.427 | 2.975 | +0.0 % |
| Stainless Steel 304 | 8,000 | 0.2890 | 4.512 | 3.032 | +1.9 % |
| Stainless Steel 316 | 8,000 | 0.2890 | 4.512 | 3.032 | +1.9 % |
| Stainless Steel 316L | 8,000 | 0.2890 | 4.512 | 3.032 | +1.9 % |
| Stainless Steel 430 | 7,700 | 0.2782 | 4.343 | 2.918 | -1.9 % |
| Aluminum 6061-T6 | 2,700 | 0.0975 | 1.523 | 1.023 | -65.6 % |
| Aluminum 5052-H32 | 2,680 | 0.0968 | 1.512 | 1.016 | -65.9 % |
| Aluminum 7075-T6 | 2,810 | 0.1015 | 1.585 | 1.065 | -64.2 % |
| Copper C11000 | 8,940 | 0.3230 | 5.042 | 3.388 | +13.9 % |
| Brass C36000 | 8,500 | 0.3071 | 4.794 | 3.221 | +8.3 % |
| Bronze C93200 | 8,800 | 0.3179 | 4.963 | 3.335 | +12.1 % |
| Titanium Grade 2 | 4,510 | 0.1629 | 2.544 | 1.709 | -42.5 % |
| Gray Cast Iron | 7,200 | 0.2601 | 4.061 | 2.729 | -8.3 % |
| Lead | 11,340 | 0.4097 | 6.396 | 4.298 | +44.5 % |
| Rigid PVC (Type I) | 1,400 | 0.0506 | 0.790 | 0.531 | -82.2 % |
| HDPE (PE 100) | 960 | 0.0347 | 0.541 | 0.364 | -87.8 % |
Same geometry throughout, so the only variable is density. Carbon steel is highlighted as the baseline.
A note on using this table for costing: mass is not price. Aluminium is roughly a third of steel's mass here, but per kilogram it costs several times more, so a straight swap rarely saves money — what it buys is reduced load on a structure or a vehicle.
About brass c36000
Free-cutting brass, roughly 61 % copper and 3 % lead, and by a wide margin the most machinable common metal — it machines at about three times the speed of 1018 steel with excellent finish. Density 8,500 kg/m³ puts it 8.3 % above carbon steel. The lead that makes it machine so well is also why it is restricted in potable-water contact under many national rules, which pushes fittings toward lead-free silicon or bismuth brasses with densities 0.5–1 % lower.
- Density
- 8,500 kg/m³ = 0.3071 lb/in³ · 1.0828× carbon steel · typical spread ±2 %
- Specification
- ASTM B16 (UNS C36000, free-cutting)
- Equivalents
- EN CW603N · JIS C3604 · GB HPb59-1
- Typical uses
- Fittings and valves · Instrument and clock parts · Electrical connectors · Decorative hardware
Lead content (typically 2.5–3.7 %) restricts use in potable water. Typical density range 8,400–8,700 kg/m³ by composition.
About rectangular tube
Rectangular tube is the shape to reach for when a beam has to be shallower than it is wide in one direction only. Because depth drives bending stiffness far more than width does, taking a rectangular section and turning it 90° changes the stiffness dramatically while the weight stays identical — a 100 × 50 × 4 tube is about 4 times stiffer about its strong axis than its weak axis, at 9.10 kg/m either way. The table here holds the common 2:1 depth-to-width proportion; enter your own dimensions in the calculator when the section is not 2:1.
Specified as depth × width × wall thickness. Confirm which dimension is the depth on a drawing before computing loads.
Download this data
Brass rectangular tube — CSV
Both buttons below read the tables rendered on this page, so the file matches what you are looking at. The full catalogue — all 16 materials across all 10 sections — is on the downloads page.
Fields are quoted per RFC 4180, with a UTF-8 byte-order mark so Excel reads the mm² and · characters correctly. Blank lines separate the weight matrix from the area matrix.
Frequently asked questions
How much does brass c36000 rectangular tube weigh?
At the reference dimensions (a = 60 mm, b = 40 mm, t = 3 mm) a brass c36000 rectangular tube of this size weighs 4.794 kg/m, or 3.221 lb/ft. The table above lists the figure for every standard size so you can read your size directly instead of scaling.
How is the weight of rectangular tube calculated?
Weight is cross-sectional area × length × density. For this shape the area is A = a·b − (a − 2t)(b − 2t). At the reference dimensions that gives 564.0 mm², and multiplying by brass c36000's density of 8,500 kg/m³ gives 4.794 kg/m. Nothing is looked up in a table — which is why a non-standard size is calculated just as accurately as a standard one.
Why does brass c36000 weigh more or less than steel?
It is heavier than carbon steel for the same section — about 8 % heavier at 8,500 kg/m³. Density is the only variable: the cross-sectional area depends purely on geometry, so a rectangular tube of the same dimensions has the same area in every material and the mass simply scales with density. In this case the ratio is 1.0828× carbon steel.
What is the cross-sectional area of a rectangular tube?
The area depends only on the dimensions, not on the material, so it is identical whichever material you select: at the reference dimensions it is 564.0 mm² (0.8742 in²). That is the number you would enter into a stress or deflection calculation, and it is why changing material on this page never changes the area column.
Does a brass rectangular tube weigh the same as a brass part of a different shape?
No, and the difference is larger than most people expect. At equal nominal size, a square bar is 27.3 % heavier than a round bar, and a hollow section is typically 60–80 % lighter than the solid bar it replaces. Weight follows area, and area changes faster than dimensions do — which is exactly why this needs calculating rather than estimating.
Should I use Brass weight or carbon steel weight for costing?
Use the material you are actually buying. At 8,500 kg/m³ against carbon steel's 7,850 kg/m³, the same rectangular tube differs by 8.3 % in mass. On a per-metre quote that is invisible; on a fabricated tonnage it is the difference between a margin and a loss. This page computes the steel figure as 4.427 kg/m for comparison.
Other materials, same rectangular tube
The same geometry in every material, so the only variable is density.
- Carbon steel rectangular tube — 7850 kg/m³
- SS 304 rectangular tube — 8000 kg/m³
- SS 316 rectangular tube — 8000 kg/m³
- AL 6061 rectangular tube — 2700 kg/m³
- Copper rectangular tube — 8940 kg/m³
- HDPE rectangular tube — 960 kg/m³
- PVC rectangular tube — 1400 kg/m³
- AL 5052 rectangular tube — 2680 kg/m³
Other Brass sections
The same density applied to every shape the site covers.
- Brass round bar — A = π/4 · d²
- Brass square bar — A = a²
- Brass hexagonal bar — A = (√3/2) · AF² ≈ 0.8660 · AF²
- Brass flat bar — A = w · t
- Brass plate — A = w · t
- Brass round tube — A = π/4 · (D² − d²), d = D − 2t
Reference data and tools
- Metal weight overview — how the calculation works
- All 16 materials — densities and specifications
- All 10 sections — formulas and size series
- Density chart — lightest to heaviest
- Metal weight calculator — any size, any material
- All calculators — metal weight and pipe weight
- Download the data — CSV, generated from the same source
- Cross-reference tables — DN / NPS / material equivalents
- Methodology and sources — where every number comes from
Rectangular Tube area from A = a·b − (a − 2t)(b − 2t). Mass computed as area × length × density at 8,500 kg/m³ (ASTM B16 (UNS C36000, free-cutting)). No weight on this page is copied from a published table — which is why figures can differ in the last significant digit from a mill's chart calculated at a nominal density.
- Elementary plane geometry. The circle, polygon and hollow-section area formulas.
- ASTM material specifications for each grade named in the material entry (A36, A240/A276, B209/B211/B221, B152/B16/B505, B265/B348, A48, B29, D1784, D3350).
- BIPM / NIST definitional constants: international inch = 25.4 mm, foot = 0.3048 m, pound = 0.45359237 kg.
Dataset version 2026.09.1 · dimensions last verified against source 2026-09-21. Found an error? Report it — corrections are issued with a version bump.