In today’s article, I will discuss a little about how the maintenance works are planned on board!
Due to the harsh conditions that ships suffer every single day due to the weather and their operation, they suffer corrosion and for that reason, they need periodic maintenance in relatively short periods of time.
To make it more difficult, ships only visit the dry dock every 3 to 5 years. Because of this, the job as to be mostly done by the crew on board the ship, in the free time between loading and unloading of cargo or at the same time as these operations.
For each type of surface, there is a different type of exigence needed so we have to use a specific type of coating/ paint.
Before starting the job:
Before starting any kind of job, the one that is responsible for organizing the maintenance work must have some aspects in mind:
- The areas that need to be repaired.
- If there is any kind of restraint to access the location of the job.
- If the work brings some kind of constraint to the ship’s normal operation.
- Safety measures that need to be taken during the job.
After these first aspects, we must think about how to execute the maintenance work:
- What are the best tools to remove corrosion/ or peeling coating?
- What are the tools used to proceed to the coating application (Brush, roller, spray-gun)?
- What PPE (Personal Protective Equipment) is needed?
- Is it necessary to interdict the area to be repaired?
- What is the best time/ condition in which the ship is to perform the maintenance work?
- Do the meteorologic conditions allow work?
- Do we have the necessary crew members available to perform the job?
After taking all of this into considerations we start the coating schedule/plan!
The coating plan is a list of products to be used and how they should be applied.
The coating plan must include:
- The sequence/number of coats in which the primer/ undercoat must be used.
- The brand and reference of the products to be used. In case of being required to use two components coating, it must be listed not only the coating itself but also the curing agent reference.
- The degree of preparation of the surface. Some coatings are more sensitive than others. For some we need to have an almost flawless surface, others admit some kind of deterioration.
- The spreading rate is the area of surface covered per coat of coating at a specified dry film thickness per unit volume of coating material. Spreading rate generally is indicated by square meter covered per liter or square feet covered per gallon of coating.
- Wet film thickness or WFT is the measured thickness of any applied wet coating that is liquid-based. A wet film thickness gage should be used by the applicator as the coating is being applied to ensure that the measurement is representative of the calculated wet film before significant solvent evaporation occurs.
- Coating dry time before next coat.
- What PPE must be used.
After the coating plan being made, we should verify that we have all the necessary material on board and if not, order it!
I took from Hempel website some of the technical information about one of their coatings.