Epoxy Anti-Corrosion Powder Coating for Coal Mine Gas Drainage Pipes

Surface Finish Options Overview

Product Introduction:

This product is formulated using phenolic epoxy resin and incorporates self-developed conductive polymers and conductive materials, combining the advantages of intrinsic and doped conductivity. It is specifically designed for conductive heavy-duty anti-corrosion powder coatings. The surface resistivity of the coating can reach below 10⁵ Ω, effectively eliminating static electricity accumulation in gas drainage pipes and preventing static sparks, thereby enhancing safety. The coating 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.

Utilizes self-developed materials combining intrinsic and doped conductivity.

Good electrical conductivity of the coating, with surface resistivity reaching 10⁵ Ω, effectively eliminating surface charge accumulation.

Forms an anti-electric field at the coating-metal interface, shielding electron transfer and protecting the metal.

Superior high-temperature cathodic disbondment resistance.

Low melting temperature, high reactivity, high curing completion rate, and good mechanical properties.

Contains flame retardants, providing certain flame-retardant effects.

Powder Coating Performance Parameters

Cured Powder Coating Performance Parameters

Compliance Standard: MT 181-88

Application Fields:

Special anti-static and anti-corrosion coating for gas ventilation and drainage pipes in coal mines.

Application Processes:

Electrostatic spraying, dip coating, roll 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 40-90 mm; dust and abrasives on the steel pipe surface should be blown clean. Preheating temperature should be controlled between 180-250°C and must not exceed 275°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 200°C to improve the curing completion rate.

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.