HDPE (PE 100) Hexagonal Bar Weight
Mass per metre and per foot for hdpe (pe 100) hexagonal bar at 960 kg/m³ (ISO 4427 / ASTM D3350 (PE 100 black)). Every figure is for the section as drawn. A 6 m length of this size weighs 2.9 kg (6.4 lb per 20 ft).
At the reference dimensions (AF = 24 mm) this section has a cross-sectional area of 498.8 mm², giving 0.479 kg/m (0.322 lb/ft). Against carbon steel's 7,850 kg/m³ that is -87.8 % — the same section in steel would be 3.916 kg/m.
Hexagonal Bar — formula and derivation
Area of a hexagonal bar
A = (√3/2) · AF² ≈ 0.8660 · AF²
A = (√3/2) × AF², where AF is the distance across flats (the wrench size), not across corners
Worked through with the default dimensions:
A = (√3/2) × AF²A = 0.866025 × 24²A = 0.866025 × 576.0A = 498.8 mm²
- AF
- Across flats (AF) — Distance between opposite flats — the size a spanner grips. Hex bar is ordered by AF, not by corner-to-corner.
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 960 kg/m³ that is 0.4789 kg/m for the reference size above.
HDPE hexagonal bar — size series
| Across flats (AF) | Cross-section | Mass / length |
|---|---|---|
| 5.0 mm | 21.65 mm² · 0.0336 in² | 0.021 kg/m · 0.014 lb/ft |
| 6.0 mm | 31.18 mm² · 0.0483 in² | 0.030 kg/m · 0.020 lb/ft |
| 8.0 mm | 55.43 mm² · 0.0859 in² | 0.053 kg/m · 0.036 lb/ft |
| 10 mm | 86.60 mm² · 0.1342 in² | 0.083 kg/m · 0.056 lb/ft |
| 12 mm | 124.71 mm² · 0.1933 in² | 0.120 kg/m · 0.080 lb/ft |
| 14 mm | 169.74 mm² · 0.2631 in² | 0.163 kg/m · 0.109 lb/ft |
| 17 mm | 250.28 mm² · 0.3879 in² | 0.240 kg/m · 0.161 lb/ft |
| 19 mm | 312.64 mm² · 0.4846 in² | 0.300 kg/m · 0.202 lb/ft |
| 22 mm | 419.16 mm² · 0.6497 in² | 0.402 kg/m · 0.270 lb/ft |
| 24 mm | 498.83 mm² · 0.7732 in² | 0.479 kg/m · 0.322 lb/ft |
| 27 mm | 631.33 mm² · 0.9786 in² | 0.606 kg/m · 0.407 lb/ft |
| 32 mm | 886.81 mm² · 1.3746 in² | 0.851 kg/m · 0.572 lb/ft |
| 36 mm | 1,122.37 mm² · 1.7397 in² | 1.077 kg/m · 0.724 lb/ft |
| 41 mm | 1,455.79 mm² · 2.2565 in² | 1.398 kg/m · 0.939 lb/ft |
| 46 mm | 1,832.51 mm² · 2.8404 in² | 1.759 kg/m · 1.182 lb/ft |
| 50 mm | 2,165.06 mm² · 3.3559 in² | 2.078 kg/m · 1.397 lb/ft |
Computed for HDPE at 960 kg/m³ (0.0347 lb/in³). ISO 4427 / ASTM D3350 (PE 100 black).
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.
Imperial sizes
Hexagonal Bar is also bought in inch sizes. The conversions below are exact (1 in = 25.4 mm by definition), so the metric equivalents are the true millimetre dimensions rather than a rounded nominal figure.
| Stock size | Metric equivalent mm | Cross-section | Mass / length |
|---|---|---|---|
| 1/4 in | 6.35 | 34.92 mm² · 0.0541 in² | 0.034 kg/m · 0.023 lb/ft |
| 5/16 in | 7.94 | 54.56 mm² · 0.0846 in² | 0.052 kg/m · 0.035 lb/ft |
| 3/8 in | 9.52 | 78.57 mm² · 0.1218 in² | 0.075 kg/m · 0.051 lb/ft |
| 7/16 in | 11.11 | 106.94 mm² · 0.1658 in² | 0.103 kg/m · 0.069 lb/ft |
| 1/2 in | 12.70 | 139.68 mm² · 0.2165 in² | 0.134 kg/m · 0.090 lb/ft |
| 9/16 in | 14.29 | 176.78 mm² · 0.2740 in² | 0.170 kg/m · 0.114 lb/ft |
| 5/8 in | 15.88 | 218.25 mm² · 0.3383 in² | 0.210 kg/m · 0.141 lb/ft |
| 3/4 in | 19.05 | 314.28 mm² · 0.4871 in² | 0.302 kg/m · 0.203 lb/ft |
| 7/8 in | 22.22 | 427.77 mm² · 0.6631 in² | 0.411 kg/m · 0.276 lb/ft |
| 1 in | 25.40 | 558.72 mm² · 0.8660 in² | 0.536 kg/m · 0.360 lb/ft |
| 1-1/4 in | 31.75 | 873.01 mm² · 1.3532 in² | 0.838 kg/m · 0.563 lb/ft |
| 1-1/2 in | 38.10 | 1,257.13 mm² · 1.9486 in² | 1.207 kg/m · 0.811 lb/ft |
| 2 in | 50.80 | 2,234.90 mm² · 3.4641 in² | 2.146 kg/m · 1.442 lb/ft |
Stock sizes in inches, converted exactly at 25.4 mm per inch. Material: HDPE (PE 100) at 960 kg/m³.
The same hexagonal bar in every material
Geometry is fixed and only density changes, so this table is the whole material-selection question in one view. HDPE (PE 100) 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 | 3.916 | 2.631 | +0.0 % |
| Stainless Steel 304 | 8,000 | 0.2890 | 3.991 | 2.682 | +1.9 % |
| Stainless Steel 316 | 8,000 | 0.2890 | 3.991 | 2.682 | +1.9 % |
| Stainless Steel 316L | 8,000 | 0.2890 | 3.991 | 2.682 | +1.9 % |
| Stainless Steel 430 | 7,700 | 0.2782 | 3.841 | 2.581 | -1.9 % |
| Aluminum 6061-T6 | 2,700 | 0.0975 | 1.347 | 0.905 | -65.6 % |
| Aluminum 5052-H32 | 2,680 | 0.0968 | 1.337 | 0.898 | -65.9 % |
| Aluminum 7075-T6 | 2,810 | 0.1015 | 1.402 | 0.942 | -64.2 % |
| Copper C11000 | 8,940 | 0.3230 | 4.460 | 2.997 | +13.9 % |
| Brass C36000 | 8,500 | 0.3071 | 4.240 | 2.849 | +8.3 % |
| Bronze C93200 | 8,800 | 0.3179 | 4.390 | 2.950 | +12.1 % |
| Titanium Grade 2 | 4,510 | 0.1629 | 2.250 | 1.512 | -42.5 % |
| Gray Cast Iron | 7,200 | 0.2601 | 3.592 | 2.413 | -8.3 % |
| Lead | 11,340 | 0.4097 | 5.657 | 3.801 | +44.5 % |
| Rigid PVC (Type I) | 1,400 | 0.0506 | 0.698 | 0.469 | -82.2 % |
| HDPE (PE 100) | 960 | 0.0347 | 0.479 | 0.322 | -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 hdpe (pe 100)
High-density polyethylene and the lightest material in the catalogue at 960 kg/m³ — it floats. That is not a curiosity: buoyancy governs how submerged outfall and intake lines are installed, and HDPE’s ability to be towed and floated into place in long strings is why it displaced steel for marine pipelines. It is also tougher than PVC at low temperature and tolerates ground movement without cracking, at the cost of much lower pressure rating at the same wall thickness.
- Density
- 960 kg/m³ = 0.0347 lb/in³ · 0.1223× carbon steel · typical spread ±2 %
- Specification
- ISO 4427 / ASTM D3350 (PE 100 black)
- Equivalents
- EN PE 100 · JIS PE100 · GB PE100
- Typical uses
- Water and gas mains · Submarine outfall lines · Landfill and leachate pipe · Geomembrane and lining
Density splits into two families: PE 100 pipe grades 950–960 kg/m³, PE 63/80 grades 930–945 kg/m³. Black compound includes ~2 % carbon black.
About hexagonal bar
Hex bar is the one shape where the ordering dimension is not the dimension the formula wants. Stock is sold by across-flats (AF) because that is what the wrench grips, but the area formula needs AF as well — and the two are easy to confuse once a drawing quotes across-corners instead. Across-corners is a factor of 2/√3 (1.1547) larger than AF, so mixing them up inflates the calculated weight by 33 %. Always check which one the drawing calls out.
Specified by across-flats. Say so explicitly on the order — "across corners" gives a different bar.
Download this data
HDPE hexagonal bar — 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 hdpe (pe 100) hexagonal bar weigh?
At the reference dimensions (AF = 24 mm) a hdpe (pe 100) hexagonal bar of this size weighs 0.479 kg/m, or 0.322 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 hexagonal bar calculated?
Weight is cross-sectional area × length × density. For this shape the area is A = (√3/2) · AF² ≈ 0.8660 · AF². At the reference dimensions that gives 498.8 mm², and multiplying by hdpe (pe 100)'s density of 960 kg/m³ gives 0.479 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 hdpe (pe 100) weigh more or less than steel?
It is lighter than carbon steel for the same section — about 88 % lighter at 960 kg/m³. Density is the only variable: the cross-sectional area depends purely on geometry, so a hexagonal bar of the same dimensions has the same area in every material and the mass simply scales with density. In this case the ratio is 0.1223× carbon steel.
What is the cross-sectional area of a hexagonal bar?
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 498.8 mm² (0.7732 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 hdpe hexagonal bar weigh the same as a hdpe 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 HDPE weight or carbon steel weight for costing?
Use the material you are actually buying. At 960 kg/m³ against carbon steel's 7,850 kg/m³, the same hexagonal bar differs by 87.8 % 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 3.916 kg/m for comparison.
Other materials, same hexagonal bar
The same geometry in every material, so the only variable is density.
- Carbon steel hexagonal bar — 7850 kg/m³
- SS 304 hexagonal bar — 8000 kg/m³
- SS 316 hexagonal bar — 8000 kg/m³
- AL 6061 hexagonal bar — 2700 kg/m³
- Copper hexagonal bar — 8940 kg/m³
- Brass hexagonal bar — 8500 kg/m³
- PVC hexagonal bar — 1400 kg/m³
- AL 5052 hexagonal bar — 2680 kg/m³
Other HDPE sections
The same density applied to every shape the site covers.
- HDPE round bar — A = π/4 · d²
- HDPE square bar — A = a²
- HDPE flat bar — A = w · t
- HDPE plate — A = w · t
- HDPE round tube — A = π/4 · (D² − d²), d = D − 2t
- HDPE square tube — A = a² − (a − 2t)²
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
Hexagonal Bar area from A = (√3/2) · AF² ≈ 0.8660 · AF². Mass computed as area × length × density at 960 kg/m³ (ISO 4427 / ASTM D3350 (PE 100 black)). 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.