NAUT SCI Paint & MARPOOL

Carbon Steel must be protected from what?

Fouling and Corrosion.

What happens if a ship is poorly painted and maintained?

It wastes time, money, and manpower and may be subject to more frequent inspections and breakdowns due to rusted equipment. It may also threaten the ship’s structural integrity and could result in leaks, cracks, or breaking up and a total loss of the ship.

What is Fouling?

Marine organism such as barnacles, mussels and marine grasses that often attach themselves to the underwater surfaces of the hull.

what climate is Fouling most common in?

Tropical waters. Fouling most often occurs at the waterline, where sunlight and water meet. They grow more densely on vessels that are moored for long periods of time.

How much can Fouling slow down a ship?

Up to 15%, with increased fuel consumption.

Fouling can also damage the hull paint, thus allowing corrosion of the steel hull. What can be done to stop this?

Special anti-fouling hull paints. Either paint with copper mixed in that act as a biocide, or a self-polishing paint, such that as the ship moves through the water, the outer layer of the coating slowly dissolves, taking marine organisms with it.

What happens when uncoated carbon steel is exposed to salt, water, and oxygen?

It turns into iron oxide (Fe2O3), better known as rust. This weakens and wastes away the steel.

What kind of reaction is Corrosion? How does it take place?

Electrochemical. It is caused when a cathode (-), and anode (+) form. Corrosion occurs at the anode (+). The potential difference between these two points determines how fast corrosion takes place.

What is a sacrificial anode?

It is the use of an impressed current applied to the hull. An example of this is zinc or aluminum anodes being welded to the hill under the propeller, with is made of bronze. Over time, the zinc gives up its ions to the bronze in an electrolytic exchange, increasing protection to the propeller.

What is a Binder?

The main film forming resin system.

What are pigments?

Particulate solids imparting specific properties such as color, mechanical properties, and anticorrosion properties.

What are additives?

Ingredients added at low level ~0.1-5% level, which impart properties such as rheological control, in-can stability, and UV resistance.

What is a Solvent?

The carrier for the system, it dissolves the binder and allows the paint to be applied. Should not be present in the dry film.

What is a coating plan?

Most ships have a paint schedule or a coating plan in which the primer, top coating, bottom paint, and boot topping are from the same manufacturer and are designed to work well together to form a coating system for the entire ship.

What is a pretreatment Coating?

A phosphoric acid that is used remove all remaining rust. This often gives off flammable and harmful fumes.

What are primers?

Paints designed to cover steel surfaces that have been prepared by removing all dirt, grease, old loose paint, and rust from the applying area.

What are Topside Paints?

After the steel surface has been coated with the primer, it is coated with a topside paint. The topside paint uses a pigment of inorganic zinc silicate, and it acts as the anode (+) and changes the steel into the cathode (-), thus preventing the corrosion of steel.

What are bottom paints?

Applied in drydock, the bottom paints have an epoxy-based vehicle, the outer layer being anti-fouling.

What is boot-topping paints?

The area of the hull near the waterline is subject to waves and greatest fouling due to sunlight. Better quality paint and more frequent paint is required here.

What PPE should one have when painting?

Goggles, Gloves and Overalls, Hat, and Respirator. If painting in an enclosed space, it should also be well ventilated.

How should paint be stored safely?

Paint should be stored in a paint locker, which is usually located in the forecastle. It should be equipped with natural and forced mechanical ventilation, a fire detection system, and a CO2 fixed firefighting system.

Does painting over rust stop corrosion?

Nope.

What are some good tips for painting?

Never paint over rubber gaskets for watertight doors, hatches and scuttles. Never paint over screw threads, name plates, air screens or zinc anodes. Never paint over letters or numbers. Never put on a thick coat. Allow paint to dry before applying more.

How does Alkyd paint dry?

Chemical drying.

How do Acrylic and Vinyl paint dry?

physical drying.

What role does the International Maritime Organization (IMO) play?

It creates the bulk of maritime rules.

What two kinds of pollution does MARPOL address?

Accidental pollution, and intentional pollution (operationally required discharges such as ballast, bilges and trash).

What are the six MARPOL Annexes?

1 = Oil; 2 = Noxious Liquid Substances; 3 = Harmful Substances in Packaged Form; 4 = Sewage; 5 = Garbage; 6 = Air Pollution.

What is the difference between operational waste and cargo waste?

Operational waste comes from running the ship; cargo waste comes from the cargo being carried.

Which U.S. law relates to Annex 1?

The Oil Pollution Act of 1990 (OPA).

What is Grey Water?

Water from sinks, washing machines, showers, etc.

What is Black Water?

Raw, untreated sewage.

When must entries be made in the Garbage Record Book?

When garbage is discharged to a reception facility onshore, incinerated, discharged into the sea, or accidentally discharged into the sea.

What is the rule in Special Areas, and where should it be noted?

NOTHING OVERBOARD. Put it on the voyage plan.

What does MARPOL stand for?

International Convention for the Prevention of Pollution from Ships.