PILE PROTECTION WRAPPING

In marine construction environments, steel pilings are exposed to natural elements that can impact their useful service life. Corrosion is one of the inevitable factors that engineers and marine contractors must consider when designing or working around these structural components. The damage caused by corroded steel can be significant. Therefore, understanding the factors that contribute to corrosion, as well as its various zones and preventive measures, is essential for ensuring the long-term durability of piling structures.

Corrosion Zones - Corrosion rates on steel piling surfaces vary considerably within few distinct zones.

Splash Zone - Considered the zone where the most serious corrosion activity occurs, the splash zone comprises the area of steel pilings at and immediately above the high tide line, which is subject to frequent wetting from splashing water.

Between this area and the immersed area, corrosion cells are produced by different oxygen concentrations. The metal underwater is anodic to the exposed area, with the corrosion rates intensifying because of the short electrical paths and tide changes.

Tidal Zone - An area of relatively low corrosion rates, the tidal zone is immersed on a part-time basis. The metal in this zone benefits from being cathodic to the metal which is slightly below low tide.

Continuously Submerged Zone - A shortage of dissolved oxygen at the water-metal interface equates to a low corrosion rate in both salt and freshwater areas that are fully immersed. A corrosion rate of 5 mm per year is used as a guide for carbon steel in seawater.

PROTECTION SYSTEM

We at Diving Task in Hong Kong offer the following pile-wrapping services:

1. Wet/Underwater Petrolatum Tape Primer:

This primer is specifically designed for damp or wet surfaces prior to applying Denso petrolatum tapes. It penetrates existing rust, displaces moisture, stabilizes the surface, and enhances adhesion.

2. Marine Petrolatum Tape with HDPE Backing

Our petrolatum tape can be used without a primer to protect dry, wet, or submerged surfaces. These tapes provide long-term protection for pipes, pilings, risers, flanges, valves, and similar surfaces.

3. Steel and Concrete Pile Protection System

This anti-corrosion protection system is suitable for medium to large piles and utilizes a proven petrolatum tape with over 35 years of experience. The SeaShield Marine Tape is safeguarded with a durable HDPE outer cover and secured with marine-grade alloy bolts.