8 January 2025
Application of a hard coat system to the tanks of a floating sheerleg
Date:
11-2024
Location project:
Rotterdam
Client:
Maritime service provider
Application:
Floating sheerleg
Product(s):
nC Corrosion Passivator Hard Coat System
Preparation:
High-pressure washing
Application method:
Spraying
During weeks 47-50 of 2024, six voids of a floating sheerleg were treated with our nC Protect X1 hard coat system specifically developed for direct application to rust, consisting of:
- nC Protect X1 Passivator
- nC Protect X1 Base Coat
- nC Protect X1 Top coat
Project Details – Floating sheerleg
- Treated surface: 6 voids of the floating sheerleg.
- Surface area: 1.550
- Project duration: 3 weeks

Pre-Treatment of the voids of the floating sheerleg
Using 500 bar high-pressure washing is essential to thoroughly clean the tanks and remove any loose coating and loose rust. It is not necessary to dry the surface with heaters after high pressure washing.
To minimize project time, a direct-over-rust solution was chosen that can be applied to damp, corroded surfaces, reducing the waiting time after high-pressure washing.
Application Process – Hard Coat – nC Corrosion Passivator
After the pretreatment procedures, the coating system can be applied directly to the (clean) corroded surface. In total 3 layers of coating have been applied:
- Layer 1: nC Protect X1 Passivator
- Layer 2: nC Protect X1 Base coat
- Layer 3: nC Protect X1 Top coat

nC Protect X1 Passivator
A corrosion passivator developed for corroded surfaces. It should only be applied to metal surfaces that are corroded, or have flash rust. This product can be directly applied to rust, effectively stopping the corrosion process. It creates a stable surface that can be coated with any one- or two-component metal primers or topcoats.
nC Protect X1 Base coat
A lead- and chromate-free 2-component epoxy primer with excellent corrosion protection, strong adhesion, and effective filling capacity.
nC Protect X1 Top coat
A fast-curing, 2-component, carbo-modified epoxy top coat with corrosion-inhibiting pigments and excellent adhesion and durability
This direct-over-rust system meets the requirements for corrosion category C5 (high) according to ISO 12944-6.
Results – Treatment of the voids of the Floating Sheerleg
As shown in the pictures, the voids are now protected with a 4-layer coating system. On December 13, 2024, an extensive coating thickness measurement was conducted in the voids by nC Protect to confirm project completion. Overall, the coating has been applied cleanly and provides uniform coverage, which will result in a long term protection of the voids against corrosion.

Conclusion – Tank conservation Floating Sheerleg
Traditional tank conservation involves the time-consuming pre-treatment of tanks through abrasive blasting. The use of the nC Protect X1 coating system enabled a direct-over-rust coating system that meets ISO C5 (high) standards. This approach reduced the project duration to just 3 weeks, resulting in significant savings for the client in both downtime and costs.
Inspection floating sheerleg
