Galvanized Seamless Steel Pipes

Galvanized seamless steel pipe is a corrosion-resistant pipe material produced by hot-dip galvanizing or electro-galvanizing, where a layer of metallic zinc is uniformly coated on the inner and outer surfaces of the steel pipe. It retains the core advantages of seamless steel pipe—no welds and strong pressure resistance—while significantly enhancing rust and corrosion resistance through the zinc layer, making it a commonly used pipe material for medium and high-pressure corrosion protection applications.

Core Characteristics

1. Dual Performance Advantages: Inheriting the characteristics of seamless steel pipe—no welds, high pressure resistance, and uniform mechanical properties—it is suitable for medium and high-pressure applications. The zinc layer isolates corrosive media and provides cathodic protection, offering 5-10 times the rust prevention capability of bare seamless pipe.

2. Strong adaptability: The connection method is the same as ordinary seamless pipes, supporting welding, flange connection, and threaded connection. It can directly replace ordinary seamless pipes of the same specification without additional adjustments to the construction plan.

3. Long service life and high cost performance: Hot-dip galvanized seamless pipes can last 15-20 years under normal outdoor use and over 30 years in buried environments, significantly reducing later maintenance and replacement costs.

Common Materials and Standards

Main base material: 20# (general-purpose for fluid transportation), Q355B (low-alloy high-pressure load-bearing type)

Base material standard: Fluid use GB/T 8163, Structural use GB/T 8162

Zinc coating standard: GB/T 13912 "Metallic Coatings" "Technical Requirements and Test Methods for Hot-Dip Galvanized Coating of Steel Components"

Typical Application Scenarios

Engineering Piping: Fire high-pressure sprinkler systems, municipal buried water supply, medium-pressure gas transmission, HVAC circulating water networks

Industrial Piping: Chemical low-pressure corrosion-resistant fluid transmission, outdoor industrial pipelines, coal mine underground water supply and drainage pipelines

Structural Support: Outdoor steel structure supports, guardrail posts, embedded high-pressure conduits, bridge prestressed sleeves

Core Difference Between Galvanized Seamless Pipe and Galvanized Welded Pipe

The core difference lies in the base material: Galvanized seamless pipe uses seamless steel pipe as its base material, with no weak points in the weld seam, resulting in strong pressure resistance and suitability for medium- and high-pressure, high-safety-requirement corrosion-resistant applications; however, it is more expensive. Galvanized welded pipe uses welded steel pipe as its base material, with the weld seam being a weak point; it is only suitable for low-pressure, normal-temperature water supply and drainage, and conduit applications, offering better cost-effectiveness.