Anti-Corrosion Powder Coating for Drinking Water Pipes

Surface Finish Options Overview

Product Introduction:

This product is formulated using special epoxy resins, dedicated curing agents, and food-grade pigments and fillers. It features high reactivity, strong adhesion, high cross-link density, and excellent resistance to chemicals, solvents, cathodic disbondment, as well as superior flexibility and impact resistance.

Product Features:

Excellent adhesion to the substrate.

Good leveling and high gloss on the coating surface.

Strong resistance to permeation and corrosion.

High surface hardness and dense coating.

Superior high-temperature cathodic disbondment resistance.

Low melting temperature, high reactivity, and high curing completion rate.

Good mechanical properties and extremely strong flexibility.

Complies with safety evaluation standards for materials in contact with drinking water.

Powder Coating Performance Parameters

Cured Powder Coating Performance Parameters

Compliance Standards: CJ/T 120-2008. GB/T 17219-1998

Application Fields:

Municipal drinking water supply pipes.

Application Processes:

Electrostatic spraying, dip coating, etc.

Precautions:

The steel pipe surface should be free of oil and moisture; the surface treatment quality should reach Sa2 1/2 level (GB/T 8923); the anchor pattern depth should be 50-90 mm; dust and abrasives on the steel pipe surface should be blown clean. Preheating temperature should be controlled between 180-230°C.

The product should be stored in a well-ventilated, dry indoor environment with a temperature below 30°C, away from heat sources, corrosive chemicals, and chemical solvents, and protected from strong light exposure. The stacking height should not exceed four layers. Avoid long-term pressure and ensure the packaging box is sealed to prevent caking and moisture, which can affect fluidization performance.

To ensure thorough curing of the epoxy coating and better anti-corrosion performance, it is recommended to preheat the steel pipe surface to above 170°C to improve the curing completion rate.

Do not mix with other anti-corrosion powders or recycled powders. Thoroughly clean the spraying equipment when changing colors to ensure drinking water safety and compliance with health standards.

FAQ

1. What is Powder Coating?

Powder coating is a dry finishing process used to apply a protective and decorative coating on metal or other surfaces. Instead of using liquid paint, fine powder particles (usually made of polyester, epoxy, or hybrid resins) are electrostatically charged and sprayed onto a conductive surface. The coated object is then baked in an oven, where the powder melts, flows, and cures into a smooth, durable finish.

Key features:

Durable, hard finish

Resistant to scratches, corrosion, and UV

Environmentally friendly (no VOCs)

2. Benefits of Powder Coating

Powder coating offers several advantages over traditional liquid painting:

Durability: Resistant to chipping, scratching, fading, and wear.

Corrosion Protection: Provides excellent protection against rust and chemicals.

Environmentally Friendly: No volatile organic compounds (VOCs) and minimal waste.

Efficiency: Overspray can be collected and reused, up to 99% material utilization.

Uniform Finish: Smooth, even coating without runs or drips.

Cost-Effective: Single-coat systems can achieve high film thickness, reducing labor and energy.

Aesthetic Variety: Wide range of colors, textures, and effects.

3. What Temperature to Cure Powder Coating

The curing temperature depends on the type of powder used:

Epoxy powder: ~160–200°C (320–392°F)

Polyester powder: ~180–210°C (356–410°F)

Hybrid (Epoxy-Polyester) powder: ~180–200°C (356–392°F)

Typical curing time: 10–20 minutes depending on thickness and oven type.

Always follow the powder manufacturer’s specifications for best results.

4. Process for Powder Coating

The powder coating process usually follows these steps:

Surface Preparation:

Clean the surface thoroughly (remove oil, grease, rust, or dirt)

Methods: chemical cleaning, sandblasting, or phosphating

Pre-Treatment:

Apply a conversion coating or primer if needed to improve adhesion

Powder Application:

Spray the powder using an electrostatic spray gun or fluidized bed

Curing:

Bake the coated object in an oven at the recommended temperature for the powder type

The powder melts and forms a continuous, smooth film

Cooling & Inspection:

Let the coated item cool

Inspect for defects, uniform coverage, and desired thickness

5. How to Spray Powder Coat

Equipment Needed:

Electrostatic spray gun

Compressed air supply

Powder feed hopper or container

Grounding of the object

Steps:

Ground the object: Ensures the charged powder is attracted to the surface.

Spray evenly: Hold the gun 6–12 inches from the surface, moving in smooth, overlapping strokes.

Apply sufficient powder: Ensure full coverage without excessive buildup.

Cure immediately: Transfer the sprayed item to the curing oven to fuse the powder into a solid coating.

Tips:

Maintain consistent speed and distance while spraying.

Use proper ventilation to reduce airborne powder accumulation.

Test a small area to check film thickness and color before full application.