What Are GI Pipes?
Conforming to IS 1239 (Part 1):2004, Galvanized Iron (GI) pipes are ERW pipes coated with zinc through hot-dip galvanizing per IS 4736, providing excellent corrosion resistance. They are the standard choice for potable water supply, plumbing, fire protection, and outdoor structural applications across India. According to the Bureau of Indian Standards, the zinc coating extends service life by 15-25 years compared to uncoated MS ERW pipes.
- Hot-dip galvanized zinc coating per IS 4736 - 300 g/m² minimum
- Available in Light (Class A), Medium (Class B), and Heavy (Class C)
- Threaded and coupled (T&C) or plain-end supply
- Corrosion-resistant - ideal for water, outdoor, and buried applications
Specifications We Stock
| 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 |
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 materials exclusively from highly reputed Indian and global steel mills, including:
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.
How To Order
- Specify nominal bore (NB), class (Light/Medium/Heavy), and quantity in meters or MT.
- Indicate end finish - threaded & coupled (standard) or plain-end.
- Confirm delivery location for freight calculation.
- Approve quotation and PO - we dispatch from Kanpur stockyard.
Get a quote for GI Pipes
Share your sizes and grade. We reply with stock, pricing, and lead time.
Frequently Asked Questions
What is the difference between GI pipes and MS pipes?
Which class of GI pipe should I use for water supply?
Do GI pipes come threaded?
Related
- GI Pipes: Kanpur wholesale supply Pricing, delivery zones, and grade options for buyers in UP and North India.
- Calculate the weight of GI Pipes for your BOQ Size, wall, and length to MT before requesting a quote.