There is no gainsaying that deepwater bodies are another realm entirely that is quite different from the dry landmass. And due to the fact that they need to carry out underwater surveys cannot be overemphasized, then it only can logically become imperative that southerndivers.com.au take about on what an underwater ship survey is and—most especially— explore the categories in which people who them falls.
By definition, an underwater ship survey is basically described as a method of surveying the underwater parts of a ship while it is still afloat the water body instead of having to dry-dock it for examination or repairs as it is usually conventionally done.
It is quite glaring that over 90% of world global trade is usually carried out by deep-water commercial ships. And averagely, there are more than 300 vessels that normally load and unload different kinds and sizes of cargoes. For this reason, the maintenance and repairs of these ships a necessity even while still afloat.
As it is with mariners, underwater surveyors are able to run some checks, report and provide worthwhile recommendations to evolving maintenance issues emanating from owners and operators of commercial ships be it on-sea or at the port. Oftentimes, an underwater ship surveyor offers survey services for draft surveys, on/off hire condition surveys and damage investigations. Others include pre-purchase surveys, P&I surveys, stability surveys, stowage, and lashing, marine insurance surveys and a couple of others.
Who needs an underwater ship survey?
Obviously, those who need to carry out underwater ship surveys are either primary ship owners or private operators who care to make efficient maintenance practices of their vessels. If you’re one, before this is put in place, you need to obtain an IWS notation for an underwater survey. After this, a request must be sent to a Ship Safety Office wherein they’re provided with information such as location, schedule and other general details of the diving company taking up the underwater ship survey.
In an underwater ship survey, the services that could be rendered include:
- Complete hull erosion inspection, cleaning, and repair
- Hull bio-security inspection and cleaning.
- Propeller cleaning and polishing.
- Suction grates and vent cleaning and repairs.
- Non Destructive Testing (NDT).
- Underwater Epoxy Paint.
- Wet Welding
- Anode inspection and replacement (Zincs).
It is important to note that in order to carry out an underwater ship survey, surveyors require to be well-equipped in knowledge and adept with practical skills that would assist them in dealing with every important of the ship as well as every activity that’s performed on it. Some of these activities include in-water class surveys, hull cleaning, underwater video or photography surveys, sonar surveys, underwater ballast tank inspection, and other maintenances.
Before an underwater ship survey could be harnessed and accomplished, certain equipment is normally put into use. They include the following:
- Diver communication system
- Surface supplied diving gear
- Diving Helmets
- Underwater cameras and lights
- CCTV underwater digital video system
- U/W welding and cutting equipment
- Ultrasonic thickness gauges
- NDT tools and equipment
Why is an underwater ship survey important?
One important reason why an underwater ship survey is highly important is that consistent dry-docking is virtually impossible. Hence, they engage in underwater inspection. This process involves skilled, qualified and well-trained divers who would go down the waterline and run checks on submerged areas of the ship. It would enable them to identify imminent problems and proffer immediate remedies. An underwater survey is what provides precautionary measures that are always aimed at preventing prolonged repairs in the future.
Below are the various types of underwater ship survey and the reasons why they are equally important:
1. General underwater survey
Basically, a general underwater ship survey focuses on the assessment of the integrity of structures. This is where divers seek to make corrections to damaged hull plates and propeller blades that have cracked or bent; clogged sea chest grids; leaking stern tube seals; worn-out anodes amongst many others.
2. Pre-sale, Pre/Post-charter survey
Many people who are looking to buy or hire a used ship would be interested to know its current state of working condition. This is because it is highly important for the purpose of its operation and valuation. An underwater ship inspection that is followed by a well-explained report will give important details to the buyer or hirer. This is in addition to the fact that classifying societies and insurance companies also demand such reports for their own personal use.
3. Pre-dry dock survey
At the dry dock, the time that a ship spends is usually important to be considered. Apart from the humongous funds, this would save, a pre-dry survey is one that would also conveniently prevent unnecessary delay thereby saving precious time.
On a final note, given that ship maintenance is a very important prerequisite for safety, operation and legal compliance of vessels on water bodies, then having an underwater ship survey is, no doubt, the way to go.
