The GI Seamless Pipe (Galvanized Iron Seamless Pipe) is one of the most widely used piping materials in India due to its strength, rust-resistance, and durability. Unlike normal welded GI pipes, a GI Seamless Pipe is made without any joints or welds, giving it higher pressure resistance and a longer lifespan.
At Udhhyog, we supply premium GI Seamless Pipes for water supply, oil & gas pipelines, firefighting systems, and construction projects. Our pipes comply with IS 1239, IS 3589, ASTM A53, and ASTM A106 standards.
This article covers everything you need to know about GI Seamless Pipe:
- Manufacturing process
- Sizes and dimensions
- IS & ASTM standards
- Price list in India (2025)
- Applications in industries
- Why Udhhyog is the best supplier
What is GI Seamless Pipe?

GI Seamless Pipe is a mild steel seamless pipe that undergoes a hot-dip galvanization process, where the pipe is coated with zinc to prevent corrosion. This makes it ideal for outdoor and underground applications.
Seamless (no welding seam)
Zinc coating for corrosion resistance
Long-lasting performance in harsh environments
Outbound link: Hot-Dip Galvanizing – Explained (Wikipedia)
Manufacturing Process
- Billet Selection – High-quality mild steel billet chosen
- Heating & Piercing – Billet heated and pierced into a hollow tube
- Elongation & Sizing – Tube stretched to required diameter & thickness
- Galvanization – Pipes dipped into molten zinc bath
- Cooling & Finishing – Pipes cooled, cut, and surface finished
- Testing – Pipes undergo hydro, ultrasonic & corrosion tests
GI Seamless Pipe vs Welded Pipe
| Feature | GI Seamless Pipe | GI Welded Pipe |
|---|---|---|
| Manufacturing | Pierced from billet (no seam) | Rolled & welded |
| Pressure Resistance | High | Medium |
| Durability | Very long | Moderate |
| Leakage Risk | Nil | Possible at weld |
| Cost | Higher | Lower |
For critical applications like water, oil & gas, always choose GI Seamless Pipe.
Properties
- Corrosion resistance (40–100 micron zinc layer)
- Leak-proof design
- High tensile strength
- Suitable for high-pressure systems
- Long lifespan (20–25 years in normal conditions)
Standards & Specifications
- IS 1239 (Part 1): For water & gas supply
- IS 3589: For water, oil, and sewage pipelines
- ASTM A53: Galvanized seamless steel pipes
- ASTM A106: High-temperature seamless carbon steel pipes
Outbound link: BIS Standards – Bureau of Indian Standards
Dimensions and Weight Chart
| Nominal Bore (NB) | Outer Diameter (mm) | Wall Thickness (mm) | Weight (kg/m) |
|---|---|---|---|
| 15 NB (½”) | 21.3 | 2.6 | 1.25 |
| 25 NB (1”) | 33.7 | 3.2 | 2.80 |
| 50 NB (2”) | 60.3 | 3.6 | 5.40 |
| 100 NB (4”) | 114.3 | 4.5 | 11.50 |
| 150 NB (6”) | 168.3 | 5.0 | 19.20 |
Internal Link: Download Full GI Pipe Chart – Udhhyog
Pipe Price List in India (2025)
| Size | Price (₹/meter) |
|---|---|
| ½” GI Seamless Pipe | ₹110 – ₹140 |
| 1” GI Seamless Pipe | ₹160 – ₹200 |
| 2” GI Seamless Pipe | ₹270 – ₹350 |
| 4” GI Seamless Pipe | ₹600 – ₹750 |
| 6” GI Seamless Pipe | ₹900 – ₹1100 |
Prices vary depending on wall thickness, zinc coating, and grade.
Internal Link: Request a Quote – Udhhyog
Applications
- Water Supply & Plumbing
- Firefighting Systems
- Oil & Gas Pipelines
- Construction & Structural Support
- Power Plants
- Industrial Air & Steam Lines
Advantages
- Long life due to zinc protection
- Stronger than welded pipes
- Leak-proof for critical systems
- Cost-effective in long term
- Safe for potable water supply
Why Choose Udhhyog as Your GI Seamless Pipe Supplier?
At Udhhyog, we provide:
- ISI & ASTM-certified GI Seamless Pipes
- Bulk stock availability
- Nationwide supply & exports
- Custom cutting & finishing
- Best prices with 24/7 support
Contact Udhhyog: +91-9311120784
Request RFQ: https://udhhyog.com/rfq
WhatsApp Us: Click to Chat
FAQs on GI Seamless Pipe
Q1. What is the lifespan of GI Seamless Pipe?
20–25 years with proper maintenance.
Q2. Can GI Seamless Pipe be used for drinking water?
Yes, safe when zinc coating is certified for potable use.
Q3. Which is better – GI Seamless Pipe or Welded Pipe?
GI Seamless Pipe is stronger and safer for high pressure.
Conclusion
GI Seamless Pipe is the most durable and corrosion-resistant piping solution for industries, construction, and utilities. With Udhhyog, you get quality assurance, certified products, and competitive pricing.
For bulk orders of GI Seamless Pipe, trust Udhhyog – India’s leading supplier.