About GI Pipes
Hot-dip galvanized steel pipes (GI pipes) manufactured by zinc coating ERW mild steel pipes per IS 4736. Available in IS 1239 light, medium, and heavy class for water supply, plumbing, fire protection, scaffolding, and agricultural applications.
Use this page as a product and specification reference. The exact material grade, dimensions, manufacturer, certification, inspection scope, quantity, price, availability, freight, and delivery timing are confirmed for the specific RFQ.
Specification reference
| Nominal Bore (NB) | 15mm (½") to 150mm (6") |
|---|---|
| Wall Thickness | Light 1.8-3.6mm, Medium 2.0-4.5mm, Heavy 2.6-5.4mm |
| Standards | IS 1239 Part 1, IS 4736 (galvanizing), ASTM A53, BS 1387 |
| Zinc Coating | Hot-dip galvanized, 300 g/m² minimum per IS 4736 |
| Lengths | Standard 6 meters, threaded & coupled with GI socket |
Confirm the exact grade, dimensions, tolerance, test certificate, and current availability for your requirement before ordering.
Common applications
- Water Supply: Municipal and residential drinking water distribution.
- Fire Protection: Fire fighting sprinkler systems, standpipe installations.
- Construction: Scaffolding, fencing, greenhouse frames, handrails.
- Agriculture: Irrigation lines, pump risers, greenhouse structures.
Source mills we work with
We procure from established Indian and global mills selected for the required grade, test certificate, and delivery schedule.
- APL Apollo
- Tata Steel
- Jindal Star
- Surya Roshni
- Hi-Tech Pipes
Applicable standards and specifications
GI pipe class A / B / C selection table
IS 1239 Part 1 specifies three wall-thickness classes for the same nominal bore. The choice is driven by working pressure and the application code.
| Class | Wall thickness (vs Light) | Application | Pressure handling |
|---|---|---|---|
| Light (Class A) | 1.0× | Internal plumbing, non-pressure drainage | Up to 3 kg/cm² |
| Medium (Class B) | 1.25× | Standard plumbing, water supply | Up to 10 kg/cm² |
| Heavy (Class C) | 1.6× | Fire hydrant, high-pressure water mains | Up to 20 kg/cm² |
Zinc coating per IS 4736 (300 g/m² minimum, triple-spot test) applies to all three classes. Medium class is the most commonly stocked grade for plumbing and water supply; heavy class is mandated for fire-protection systems per NBC 2016 Part 4 and IS 15105.
What to include in the RFQ
- Specify the relevant standard or grade where known.
- Provide OD or NB, wall thickness or schedule, required length, and quantity.
- State the delivery city or PIN code and any unloading constraints.
- List MTC, IBR, TPI, marking, inspection, or other documentation requirements.