GI and BI pipe supplier Philippines.
Steel pipe to ASTM A53, sized by nominal bore, standard 6.0m lengths. BI (black iron) is uncoated; GI (galvanized) is hot-dip zinc-coated for corrosion resistance — same steel, same dimensions.
Sizes and weights
ASTM A53 / ASME B36.10M · Schedule 40 (standard wall)
| Nominal size | OD (mm) | Wall (mm) | kg/m | kg per 6.0 m |
|---|---|---|---|---|
| 1/2" | 21.3 | 2.77 | 1.27 | 7.62 |
| 3/4" | 26.7 | 2.87 | 1.69 | 10.14 |
| 1" | 33.4 | 3.38 | 2.5 | 15 |
| 1-1/4" | 42.2 | 3.56 | 3.39 | 20.34 |
| 1-1/2" | 48.3 | 3.68 | 4.05 | 24.3 |
| 2" | 60.3 | 3.91 | 5.44 | 32.64 |
| 2-1/2" | 73 | 5.16 | 8.63 | 51.78 |
| 3" | 88.9 | 5.49 | 11.29 | 67.74 |
| 4" | 114.3 | 6.02 | 16.07 | 96.42 |
Weights are plain-end bare pipe; galvanizing adds roughly 3–5%. “Schedule 20” in the 1/2"–4" range is not an ASME-defined wall — it is a lighter commercial wall that varies by mill, which is why it isn’t tabulated here.
Grades
- ASTM A53 Grade A / Grade B. Schedule 40 = standard weight wall.
How it's sold
Sold per 6.0m length, black (BI) or galvanized (GI). Thin-wall “S-20” commercial pipe is also available — wall varies by supplier, so we confirm it on the quote. Send your list — spec sheet, drawing or BOQ — and we quote it back the same day.
Where it's used
Water lines and railings in GI; fire lines and fabrication in BI — the everyday job for each finish.
Common questions
What is the difference between BI and GI pipe?
Same ASTM A53 steel and dimensions. BI is uncoated (structural work, gas/steam, painted applications). GI is hot-dip galvanized for water lines, railings and outdoor work; the zinc adds about 3–5% weight.
Schedule 40 vs Schedule 20?
Schedule 40 is the full standard wall shown above. PH “Schedule 20” is a lighter, thinner commercial wall that is not ASME-standardized at these sizes — confirm the actual wall thickness before structural use.
Why is the actual diameter bigger than the size?
Pipe is sized by nominal bore, not outside diameter. A 1" pipe has a 33.4mm OD; a 2" pipe has a 60.3mm OD.
Can GI/BI pipe be used structurally?
Yes — railings, canopies, fence posts, light scaffolding. For load-bearing use, confirm the schedule, since thin-wall pipe is much weaker.
Related steel
Specs reviewed July 2026 · Southend Construction & Industrial Supplies, Dasmariñas, Cavite