MarineLine® E-Newsletters

Profitable Tanker News about Marine Cargo Tank Coatings
Issue 06
3rd in a 3-Part Series on...
Taking Care of Your Cargo Tank Coating
So far, Advanced Polymer Coatings has talked about 1) how proper application and heat curing are the first steps to a successful MarineLine® 784 coating system, and 2) how good tank cleaning methods and procedures can enhance the life of the coatings. In this third article, APC presents the importance of cargo tank coating maintenance.

Cut costs. Reduce operating budgets. Chop overhead. Save money. It seems the trend today is for ship owners and operations managers to trim operating costs at every corner. However, when it comes to taking care of your cargo tank coating — the lifeblood of a chemical or product tanker —cutting back short-term on maintenance coatings care will have the opposite effect on long-term profit. If you address minor cargo tank coating issues when they arise, you will save significantly and enhance your ROI. So the best avenue to control your operating costs is to plan ahead for regular inspections and act when minor situations call for maintenance. Inside Tank
MarineLine 784Inspecting, monitoring and taking care of your MarineLine® 784 coating will pay you extra dividends as you maintain peak operating efficiency. Here are some basic steps to employ.
1 Set up a regular coating inspection and maintenance procedure for your crew to check and take care of mechanical damages and/or other coating problems that occur in day-to-day vessel operations.
2 Contact APC for an annual onboard coating inspection of the cargo tanks of MarineLine® coating integrity (as shown in photo above), for coating areas exhibiting wear and tear, for a review of types of cargoes carried, and for general cleaning procedures used. APC will provide an overall assessment of the coating with repair recommendations, and can provide your crew with training on basic MarineLine® coatings maintenance, if requested.
3 If major repairs or re-coating is needed, schedule this work at your next planned drydocking. If minor on-board repairs can solve the coating issues, use specially engineered MarineMend coating repair kits from Advanced Polymer Coatings to repair MarineLine®. Each MarineMend Repair Kit contains a two-part coating system as shown in the photos below. A grey basecoat is first applied to the repair area, followed by a grey topcoat.
  The coatings can be easily applied by brush or using the enclosed mini-sprayer in the kit. Heat curing is required for optimum performance. Complete repair instructions are provided by APC. In a future issue of “Profitable Tanker” we will take a more detailed look at MarineMend.


Tank Coating Problems That Can Arise
Note that all cargo tank coatings, including MarineLine®, can be affected by a number of factors including:

Underlying substrate and its strain rate

In marine environments, there is significant flex and stress of the cargo tank steel substrate, which can impact the coating. MarineLine® coating is designed to closely mirror the flexibility and elongation of steel, so the coating expands and contracts with the substrate. However, sometimes the underlying steel substrate undergoes excessive movement or deformation that can cause cracks, especially at welds. This also affects the coating so it is important to regularly monitor and provide minor repairs of coating cracks that may appear. APC recommends that ship designers ensure that cargo tank areas that are prone to extreme shear and stress be carefully designed with minimum relative strain to ensure sound coatings performance.

Humidity, temperature, improper chemical exposure and improper cleaning
All these factors can impact the life of the MarineLine® cargo tank coating when they are ‘out of operating specifications.’ For example, after carrying Methanol in MarineLine® cargo tanks, APC states: DO NOT STEAM, as tanks should first be force air dried for 24 hours. And before carrying Methanol, if the tanks have been steam cleaned, tanks must be allowed to cool to 30-40°C before loading. A review of the APC MarineLine® Chemical Resistance Guide on the APC website will provide many answers on what cargoes can be safely carried and any special operating notes on these.

Mechanical damage

Although MarineLine® has a tougher and more flexible surface than most other coatings, it still can be damaged by outside factors. When equipment repairs or installations are done inside tanks, mechanical damage can occur from dropped hammers and other equipment, ladders and scaffolding that scrape the coating, or heavy foot traffic, among other factors. These minor problems need to be addressed promptly so they don’t lead to larger repairs in the future.

Long-term service
While MarineLine® has performed admirably in hundreds of ships that employ good maintenance and care, in time the coating may need to be replaced. This is just common sense as all equipment, coatings included, has ‘wear and tear.’ Just how long the MarineLine® coating may continue to perform will be answered by the recommended APC coatings inspection. Proper cleaning, with careful maintenance and repair as needed should provide years of profitable cargo tank service with MarineLine®.

If you have questions on the maintenance of your MarineLine® 784 cargo tank coating, contact your Advanced Polymer Coatings’ representative to learn more why MarineLine® 784 is unique in the maritime industry.

To read all three enewsletters in the series, ‘Taking Care of Your Cargo Tank Coating’, click on the links below: