GRP Tank
Rectification Works
Structural assessment, re-lamination, and leak sealing of GRP storage tanks restoring full-service capacity without costly replacement.
Overview
GRP storage tanks can suffer structural degradation over time due to impact, thermal cycling, UV exposure, chemical attack, or manufacturing defects. ESA provides comprehensive GRP tank rectification works from minor crack repair to full internal re-lamination restoring structural integrity and extending service life by 15–25 years.
💡 Many GRP tanks written off by facility managers can be economically restored to full operational status. ESA’s technical assessment process identifies the true extent of damage and prescribes the minimum intervention required. |
SCOPE OF WORK
- Full tank inspection — structural survey, UT thickness testing, visual assessment
- Leak source identification — dye testing, hydrostatic mapping
- Damage removal and surface preparation — grinding, grit blasting, solvent wipe
- Crack sealing and void filling with compatible resin system
- Structural patch lamination — CSM layup to match original wall specification
- Full internal relamination where specified
- Anti-bacterial coating for potable water tanks
- External UV-resistant gelcoat application
- Post-repair water test and sign-off documentation
TECHNICAL SPECIFICATIONS
| Repair Reinforcement | E-Glass CSM — 300 / 450 g/m² per layer |
| Resin — Potable Water | Food-grade Isophthalic Polyester (WRAS approved type) |
| Resin — Chemical Service | Vinyl Ester or Epoxy — depending on stored fluid |
| Internal Coating | NSF/ANSI 61 listed food-grade topcoat (potable water) |
| External Coating | UV-resistant isophthalic gelcoat — 0.4 to 0.6mm DFT |
| Post-Repair Test | Water fill to full capacity — 24-hour hold, zero leakage |
| Design Life (post-repair) | 15–25 additional years (condition dependent) |
| Standards | ASTM D3299, BS 4994, ISO 14692 |
Rectification Methodology
Tank Dewatering & Cleaning
Tank emptied, cleaned, and degassed. Confined space entry procedures applied. Tank ventilated and atmospheric monitoring established.
Structural Survey
Full internal and external inspection photographed and mapped. Ultrasonic wall thickness measurement at 300mm grid. Delamination tap-test survey.
Damage Removal & Preparation
Damaged areas ground back to clean glass — delaminated zones cut out. Edges chamfered at 30:1 taper ratio. Surface degreased with approved solvent.
Lamination Repair Works
Catalysed resin applied. CSM layers built up to match original specification. Air exclusion confirmed. Exotherm monitored.
Coating Application
Internal food-grade or chemical-resistant topcoat applied. External gelcoat applied. DFT measurements recorded.
Water Fill Test
Tank filled to 100% capacity. 24-hour hold period. Full circumferential inspection. Zero leakage required for sign-off. Test record issued.
ESA
GRP Tank Leaking or Degraded?
Get a structural assessment before committing to costly replacement.