What High-Zinc-Coating Angle Bars Are
High-zinc-coating angle bars are L-shaped steel sections protected by a thick hot-dip galvanized layer, applied either by the continuous process for pre-galvanized bars or by batch dipping to BS EN ISO 1461. The heavy zinc coating provides a long maintenance-free service life in outdoor, industrial and coastal environments, and the sections are widely supplied in grades such as A36, SS400, Q235B, Q195, S355JR and S235JR.
Why Coating Weight Matters
The corrosion life of a galvanized section is directly related to the mass of zinc on the surface. High-zinc coatings resist the development of red rust for longer, tolerate mechanical damage better and protect cut edges by cathodic action. For aggressive environments, specifying a heavier coating such as Z275 or above is a cost-effective way to extend the structure's design life.
Available Steel Grades
ASTM A36: minimum yield 250 MPa, tensile 400-550 MPa; the default structural grade for North American projects
JIS G3101 SS400: minimum yield 245 MPa, tensile 400-510 MPa; common in Asian specifications
GB/T 700 Q235B: minimum yield 235 MPa, tensile 370-500 MPa; an economical mild steel grade
EN 10025 S355JR and S235JR: minimum yield 355 MPa and 235 MPa respectively; European structural grades
Equal and Unequal Angle Forms
Galvanized angle bars are produced as equal-leg sections, such as 40 x 40 x 4 mm, and unequal-leg sections, such as 75 x 50 x 6 mm, covering a range from small 20 mm legs up to 200 mm heavy sections. Standard lengths of 6 m and 12 m are delivered with coating inspection and dimensional checks, and bars can be pre-punched or cut to length before galvanizing.
Typical Applications
Transmission towers, antenna masts and outdoor support frames
Greenhouses, agricultural buildings and animal housing
Handrails, balustrades, stair stringers and walkways
Solar mounting structures, cable trays and pipe racks
Frequently Asked Questions
Q: What does a high zinc coating mean in practice?
It means a heavier hot-dip galvanized layer, typically 275 g per square metre total or more, giving longer protection in outdoor and coastal conditions with less frequent maintenance.
Q: Which grade is best for galvanized angle bars?
There is no single best grade; A36 and SS400 suit general structures, Q235B is economical, and S355JR provides higher strength where loads are greater.
Q: Are galvanized angles suitable for welding?
Yes, but it is preferable to weld first and galvanize afterwards so that welds receive the same zinc protection as the parent material.
Q: What is the difference between equal and unequal angle?
Equal angles have two legs of the same width while unequal angles have legs of different widths; the choice follows the connection detail and load path of the structure.
Q: What lengths are standard for galvanized angle?
The most common lengths are 6 m and 12 m, and sections can be cut, drilled or punched to project requirements before coating.