Painting Ships in Dry Dock: Strategies and Challenges

When a large ship is put into dry dock, the process of painting can become complicated, particularly for areas covered by supporting blocks. This article examines the strategies and challenges involved in painting these spots, and whether it is practical to leave certain sections un-painted.

Introduction to Dry Docking and Painting

During dry docking, ships are lifted out of the water and supported by a series of blocks, allowing for maintenance, inspections, and painting. Dry docking is a critical phase in a ship's life cycle, as it offers an opportunity to address necessary repairs and upgrades.

Painting Strategies

The painting process in dry dock can vary depending on the block arrangement and the specific needs of the ship. Typically, blocking plans in ships have an A/B arrangement. This means that during an "A" block docking, some areas such as the bilge regions would be exposed, and would subsequently be painted when the ship is docked on "B" blocks. Conversely, the areas covered by the A blocks would be left un-painted during the first docking and would be addressed during the B docking.

Another strategy involves performing a fleeting: a brief process of floating the ship, shifting it to uncover the block spots, and then re-landed. However, this is only feasible if the protruding hull components such as sensors, radar domes, etc., permit such movement. This requires a careful measurement and re-pumping of water to position the ship accurately.

Preparing for Re-landing

Before a ship is flooded back into the water, the support blocks are meticulously placed in their positions using Surveyors Transit methods. Detailed records are maintained in the ship's documentation and possibly by the shipyard. This process involves several steps, including:

Using Transits to precisely position the blocks. Maintaining a detailed record of the block positions. Shifting the ship using Transits to ensure it is accurately located on the blocks.

Upon re-docking, the previous block positions are recalculated, and the sections previously covered are now scraped, primed, and painted.

Preventive Measures Against Corrosion

Leaving certain sections unpainted can be risky, as these areas may become preferentially corroded, leading to potential failures. During the last project, I personally experienced this, and the importance of thorough priming and painting cannot be overstated. Retaining the techniques and insights gained from such projects is invaluable for future maintenance and repair operations.

Conclusion

In conclusion, while painting ships in dry dock presents unique challenges, meticulous planning, and adherence to best practices can ensure that the entire surface is adequately protected. Leaving unpainted areas can lead to corrosion, necessitating additional maintenance work and potentially compromising the safety and functionality of the vessel.