Introduction

FRP water tank lining anti-corrosion technology directly determines service life. Beijing Yuanhui FRP Co., Ltd., with 15 years of production experience, found that over 60% of early failures stem from improper lining treatment. This article covers material selection, construction parameters, and quality testing.

1. Lining Material System

1.1 Resin Matrix Selection

Iso-polyester resin withstands 80°C for general water storage; vinyl ester resin extends lifespan by 3x in strong acid (pH≤2). Beijing Yuanhui uses bisphenol A epoxy vinyl ester, improving chemical resistance by 40% over standard resin.

1.2 Reinforcement Matching

The lining must use C-glass veil (30g/m²) combined with chopped strand mat (450g/m²), achieving porosity below 3%. Field data shows permeability reduced to 10⁻¹⁰ cm/s level.

2. Critical Construction Parameters

2.1 Surface Preparation

Substrate roughness must reach Rz 50-80μm via grit blasting to Sa2.5. Verified in 12 Beijing-Tianjin-Hebei projects, this standard boosts adhesion from 5MPa to 8MPa.

2.2 Interlayer Timing

Gel time set to 25-35 min (25°C); interlayer interval ≤1.5x gel time. Exceeding this increases delamination risk by 27% per ASTM D2583.

3. Common Failures & Solutions

3.1 Bubbles & Pinholes

Use three-roll coating + vacuum assist at -0.08MPa for 2 min. In a chemical plant case, pinhole density dropped from 5/m² to 0.3/m².

3.2 Stress Cracking

Lining thickness ≥2mm, corner radius ≥5mm. Beijing Yuanhui applied elastic transition layer (5% PU-modified resin) in a 50m³ tank, boosting thermal cycle resistance from 200 to 1500 cycles (80℃↔20℃).

4. Quality Testing & Standards

Per JC/T 658.1-2018, spark testing at 5kV/mm. Beijing Yuanhui uses ultrasonic thickness gauge (±0.05mm) paired with Barcol hardness tester (≥35) for dual verification.

Conclusion

FRP tank lining anti-corrosion requires systematic design: material, process, and testing are interdependent. Beijing Yuanhui recommends full inspection every three years for long-term reliability.