Description
GI Angles (Galvanized Iron Angles) | IS 808 / IS 2062 / IS 2629 Certified
Hot-Dip Galvanized Structural Steel Angles for Outdoor, Industrial & Corrosion-Prone Applications
Overview
GI Angles, also known as Galvanized Iron Angles or Hot-Dip Galvanized Steel Angles, are L-shaped mild steel structural sections that have undergone the hot-dip galvanization process — immersing the base MS angle in a bath of molten zinc at approximately 450°C to form a metallurgically bonded, highly durable zinc coating. The result is a structural angle that combines the inherent strength and weldability of mild steel with outstanding long-term resistance to corrosion, rust, and environmental degradation.
GI Angles are manufactured from IS 2062 Grade E250 mild steel, dimensioned as per IS 808:1989, and galvanized in compliance with IS 2629 — the Indian Standard for hot-dip galvanizing of iron and steel. Available in Equal Leg configurations across a wide range of sizes, GI Angles are the material of choice wherever structural steel will be exposed to moisture, outdoor weather, coastal environments, or aggressive industrial conditions.
We stock ISI-certified GI Angles with zinc coating of 86 microns and above, suitable for government-approved projects including MES, Railways, CPWD, and State PWD works.
GI Angle vs MS Black Angle — Which One Do You Need?
| Parameter | GI Angle (Galvanized) | MS Black Angle |
|---|---|---|
| Corrosion Resistance | Excellent — zinc sacrificial coating | Low — prone to rust without painting |
| Surface Finish | Bright zinc / spangle finish | Black mill scale finish |
| Recommended For | Outdoor, coastal, agricultural, govt. projects | Indoor fabrication, concrete-embedded use |
| Maintenance | Very low — self-protecting zinc layer | Regular painting/coating required |
| Service Life | 25–50+ years depending on environment | Moderate — depends on protective treatment |
| Cost | Slightly higher upfront | Lower upfront cost |
| Weldability | Good — ventilation required during welding | Excellent |
Rule of thumb: Use GI Angles wherever the structure will face outdoor exposure, moisture, rain, coastal air, agricultural conditions, or where maintenance access is difficult. Use MS Black Angles for indoor fabrication, concrete-embedded applications, or where post-fabrication painting will be applied.
The Hot-Dip Galvanization Process
What makes GI Angles superior to simply painting or priming a steel angle is the metallurgical bond formed during hot-dip galvanization. The process involves several carefully controlled stages:
- Degreasing — The MS angle is cleaned in an alkaline solution to remove oil, grease, and surface contaminants
- Pickling — Dipped in dilute acid solution to strip mill scale, rust, and oxide layers from the steel surface
- Rinsing — Washed in clean water to neutralize and remove acid residue
- Fluxing — Treated with a flux solution (as per IS 2629) to prevent re-oxidation and promote zinc adhesion
- Hot-Dip Galvanizing — Immersed in a bath of molten zinc at approximately 450°C; zinc bonds metallurgically with the steel surface forming multiple intermetallic zinc-iron alloy layers topped with a pure zinc outer layer
- Quenching & Inspection — Cooled, inspected for coating uniformity, and tested for coating thickness
The zinc used in the galvanizing process conforms to IS 209:1992 with a minimum purity of 99.995%, ensuring a coating that is dense, uniform, and tightly bonded to the base steel.
Why Hot-Dip Galvanizing Outperforms Paint and Primer
- Sacrificial Protection — Zinc corrodes preferentially before the underlying steel, actively protecting the base metal even if the coating is scratched or damaged
- Complete Coverage — Molten zinc penetrates recesses, corners, edges, and hidden surfaces that paint brushes or spray systems cannot reach uniformly
- Metallurgical Bond — The zinc-iron intermetallic layers formed are harder than the base steel itself, providing exceptional resistance to mechanical damage during handling, transportation, and installation
- No Field Touch-Up Required — Unlike painted steel which requires periodic repainting, hot-dip galvanized sections need no on-site maintenance coating after installation
- Long Proven Life — Expected service life of 25–50+ years in most environments and over 20 years even in severe urban and coastal exposure
- Easy Visual Inspection — Coating thickness and uniformity can be assessed visually and verified quickly using simple non-destructive magnetic thickness gauges
Grades & Standards
| Standard | Description |
|---|---|
| IS 808 : 1989 | Dimensions and sectional properties of hot-rolled steel angles |
| IS 2062 : 2011 (E250) | Base material — mild steel chemical and mechanical requirements |
| IS 2629 : 1985 | Hot-dip galvanizing process standard for iron and steel |
| IS 2633 : 1986 | Method of testing uniformity of zinc coating |
| IS 6745 : 1972 | Method of determination of mass of zinc coating |
| IS 4759 : 1996 | Hot-dip zinc coatings on structural steel and allied products |
Product Specifications
| Parameter | Specification |
|---|---|
| Base Material Grade | IS 2062 E250 (Fe 410W) |
| Dimensions Standard | IS 808 : 1989 |
| Galvanizing Standard | IS 2629 / IS 4759 |
| Type | Equal Leg Angle (EA) |
| Size Range | 25 x 25 x 3 mm to 150 x 150 x 12 mm |
| Zinc Coating Thickness | Minimum 86 microns (typical: 86–120 microns) |
| Zinc Coating Mass | Minimum 610 g/m² |
| Zinc Purity | 99.995% as per IS 209 |
| Standard Lengths | 6 m (custom cut-to-length available) |
| Surface Finish | Bright zinc spangle / hot-dip galvanized |
| Approvals | MES Approved, Railway Approved, CPWD / PWD Acceptable |
| HSN Code | 7216 |
Equal Angle — Size & Weight Reference Chart
| Size (mm) | Thickness (mm) | MS Weight (kg/m) | Approx. GI Weight (kg/m) |
|---|---|---|---|
| 25 x 25 | 3 | 1.14 | 1.18 |
| 30 x 30 | 3 | 1.39 | 1.44 |
| 40 x 40 | 5 | 2.97 | 3.05 |
| 45 x 45 | 5 | 3.38 | 3.47 |
| 50 x 50 | 5 | 3.77 | 3.87 |
| 50 x 50 | 6 | 4.47 | 4.59 |
| 65 x 65 | 6 | 5.84 | 5.99 |
| 75 x 75 | 6 | 6.84 | 7.01 |
| 75 x 75 | 8 | 8.96 | 9.19 |
| 90 x 90 | 8 | 10.80 | 11.07 |
| 100 x 100 | 8 | 12.10 | 12.41 |
| 100 x 100 | 10 | 14.90 | 15.28 |
| 130 x 130 | 10 | 19.70 | 20.20 |
| 150 x 150 | 12 | 27.30 | 27.99 |
GI angle weights are marginally higher than MS black angles due to the additional zinc coating mass. Confirm exact weights with MTC for critical structural calculations.
Mechanical Properties (Base Material — IS 2062 E250)
| Property | Value |
|---|---|
| Min. Yield Strength | 250 MPa |
| Min. Tensile Strength | 410 MPa |
| Min. Elongation | 23% |
| Charpy Impact (min.) | 27 J at 0°C |
Chemical Composition (IS 2062 E250)
| Element | Max. Content |
|---|---|
| Carbon (C) | 0.23% |
| Manganese (Mn) | 1.50% |
| Silicon (Si) | 0.40% |
| Sulfur (S) | 0.045% |
| Phosphorus (P) | 0.045% |
| Carbon Equivalent (CE) | 0.42% max. |
Key Features & Benefits
- Superior Corrosion & Rust Resistance
- Metallurgically Bonded Zinc Coating — Not Just Paint
- Sacrificial Zinc Protection — Self-Healing at Scratches & Cut Edges
- Service Life of 25–50+ Years in Most Environments
- 86 Microns+ Zinc Coating for Heavy-Duty Protection
- MES, Railway & CPWD Approved
- Zero Maintenance After Installation
- ISI Certified — IS 808 / IS 2062 / IS 2629 Compliant
- Available in Standard & Custom Cut Lengths
- Mill Test Certificates (MTC) Available on Request
Applications
GI Angles are the preferred structural section wherever durability, corrosion resistance, and low maintenance are critical:
Power Transmission & Telecom:
- Transmission line towers and sub-transmission line structures
- Telecom and communication towers
- Power distribution cross-arms, stay frames, and pole hardware
- Sub-station structures, busbar supports, and cable trays
- Railway Over Head Equipment (OHE) structures
Construction & Infrastructure:
- Roof trusses, purlins, and rafters in industrial and agricultural buildings
- Structural frameworks for outdoor sheds, warehouses, and storage facilities
- Scaffolding and formwork support in coastal and humid environments
- Bridge bracing members and handrail posts
- Highway and road sign gantry structures
Agriculture & Rural Infrastructure:
- Greenhouse and polyhouse structural frames
- Shade net and net house support structures
- Irrigation system support frames and pump station structures
- Livestock enclosure fencing frameworks
- Rural electrification structures
Marine & Coastal Applications:
- Jetty and dock structural frameworks
- Port and harbor support structures
- Coastal building frames and corrosion-prone environments
Industrial & Fabrication:
- Cable tray supports and electrical cable management structures
- Equipment skids, machine bases, and support frames in wet environments
- Conveyor frames in food processing, chemical, and outdoor industrial plants
- Storage racks and shelving in open warehouses and outdoor yards
Solar & Renewable Energy:
- Ground-mounted solar panel module mounting frames in open field conditions
- Rooftop solar structures in coastal and high-humidity zones
- Solar pump mounting frames in agricultural and rural installations
Applicable Standards & Certifications
| Standard | Description |
|---|---|
| IS 808 : 1989 | Dimensions for Hot Rolled Steel Angle Sections |
| IS 2062 : 2011 | Hot Rolled Structural Steel — Chemical and Mechanical Requirements |
| IS 2629 : 1985 | Recommended Practice for Hot-Dip Galvanizing on Iron and Steel |
| IS 2633 : 1986 | Testing Uniformity of Zinc Coating on Galvanized Articles |
| IS 6745 : 1972 | Determination of Mass of Zinc Coating on Zinc-Coated Iron and Steel Articles |
| IS 4759 : 1996 | Hot-Dip Zinc Coatings on Structural Steel and Allied Products |
| IS 209 : 1992 | Zinc Ingot Purity Standard (99.995% min.) |
All GI Angles are supplied with zinc coating thickness test reports and Mill Test Certificates (MTC) per EN 10204 3.1 on request.
How to Choose Between GI Angle and MS Black Angle
| Condition | Recommended Product |
|---|---|
| Outdoor, exposed to rain / moisture | GI Angle |
| Coastal, marine, or high-humidity environment | GI Angle |
| Government / MES / Railway / CPWD project | GI Angle |
| Transmission towers, telecom structures | GI Angle |
| Indoor fabrication, painted after welding | MS Black Angle |
| Embedded in concrete or grouted in masonry | MS Black Angle |
| General fabrication where corrosion is managed | MS Black Angle |
Frequently Asked Questions (FAQs)
Q: What is a GI Angle and how is it different from an MS Black Angle? A GI Angle is an MS structural angle that has been hot-dip galvanized — coated with a layer of pure zinc (99.995% purity) through immersion in molten zinc at ~450°C. The zinc coating bonds metallurgically with the steel and provides long-term corrosion protection. MS Black Angle is the same section without any galvanizing, in its natural mill finish state, and is more suited for indoor or coated applications.
Q: What is the minimum zinc coating thickness on GI Angles? As per IS 2629 and IS 4759, the minimum zinc coating thickness on structural GI Angles is 86 microns, with a zinc mass of 610 g/m² minimum. Many suppliers, including our stock, provide 86–120 microns of zinc coating for enhanced protection.
Q: How long do GI Angles last outdoors? Hot-dip galvanized angles have an expected service life of over 50 years in most rural environments and 20–25+ years in severe urban or coastal conditions — making them a highly economical long-term choice despite the slightly higher upfront cost compared to MS Black Angles.
Q: Are GI Angles approved for MES and Railway projects? Yes. Hot-dip galvanized structural angles conforming to IS 2629 / IS 4759 with the required zinc coating thickness are approved for use in MES (Military Engineer Services), Indian Railways, CPWD, and State PWD projects. Test certificates and MTC can be provided on request.
Q: Can GI Angles be welded? Yes, but welding galvanized steel requires proper ventilation and personal protective equipment, as zinc fumes released during welding can be hazardous. It is recommended to grind off the zinc coating in the weld zone, weld the joint, and then touch up the weld area with a zinc-rich cold galvanizing compound to restore corrosion protection.
Q: What standard lengths are GI Angles available in? Standard supply length is 6 meters. Custom cut-to-length is available on request to reduce on-site waste and cutting effort.
Q: What is the HSN Code for GI Angles? The HSN Code for Galvanized Iron / Galvanized Steel Angles is 7216.
GI Angles — Hot-Dip Galvanized. Corrosion Proof. Built to Last Decades.
Key Features
- Available in Standard & Custom Cut Lengths
- Easy to Cut, Drill, Punch & Fabricate
- Excellent Weldability
- High Structural Strength
- Hot-Dip Galvanizing Available for Corrosion Protection
- ISI Marked — IS 808 / IS 2062 Certified
- L-Shape Provides Dual-Plane Support
- Mill Test Certificates (MTC) Available on Request
- Versatile in Equal & Unequal Configurations
- Wide Size Range for Every Application
