Galvanized Steel Pipe & Tubing

Flo-Coat is an in-line galvanizing process that bonds a zinc coating directly to steel tubing during manufacturing. Unlike post-galvanized tubing, the Flo-Coat method creates a metallurgically bonded triple-layer coating (zinc alloy, pure zinc, and clear organic topcoat) that provides continuous corrosion protection inside and out.

Sonco stocks Flo-Coat tubing in round, square, and rectangular profiles for applications where long-term durability is critical. Customized specifications available.

The triple-layer system works by combining three distinct protective barriers. The inner zinc-iron alloy layer bonds metallurgically to the steel substrate, followed by a pure zinc layer that provides sacrificial corrosion protection. The final clear organic topcoat seals the surface against moisture and oxidation.

With this multi-layer approach, Sonco’s galvanized tubing outperforms single-coat alternatives in salt spray and outdoor exposure tests.

Yes, welding galvanized steel tubing is safe when proper ventilation and safety precautions are followed. The zinc coating produces fumes during welding that require adequate exhaust ventilation or respiratory protection per OSHA guidelines.

Many fabricators grind the zinc coating back 1-2 inches from the weld zone to minimize fume generation and improve weld quality, then apply a cold galvanizing compound to restore corrosion protection after welding.

Galvanized tubing provides a smoother, more uniform surface than raw steel. This premium foundation ensures that powder coating adheres more evenly and lasts longer. The zinc layer underneath acts as a secondary barrier against corrosion if the powder coat is scratched or chipped, giving the finished product a dual-defense system.

Sonco’s Flo-Coat tubing is frequently specified for architectural and ornamental projects where a powder-coated finish over galvanized steel delivers long-term performance and the desired aesthetic.

Modern in-line galvanized tubing like Flo-Coat is engineered to withstand standard fabrication processes, including bending, swaging, flaring, and punching, without significant coating loss.

The metallurgically bonded zinc layer flexes with the steel rather than flaking off. This is a key advantage over hot-dip galvanized tubing. For tight-radius bends, some minor surface cracking of the topcoat may occur, but the zinc alloy layer continues to provide cathodic protection.

Sonco offers galvanized steel tubing in round, square, and rectangular profiles across a wide range of sizes.

Round tubing is available from 1/2-inch OD through 6-inch OD, while square and rectangular sections range from 1/2-inch to 6-inch. Wall thicknesses vary by profile and application, with common gauges spanning from 18-gauge to 7-gauge.

Custom lengths and cut-to-size options are available for project-specific requirements.