VNS – Vietnam Ship Services Company provides underwater hull inspection and cleaning for vessels calling at ports and anchorages across Vietnam. Our certified commercial divers inspect, clean and repair the underwater parts of the ship while it stays afloat. As a result, you can check damage, remove marine growth and restore hull and propeller performance without taking the vessel to drydock.
We carry out underwater inspection (UWI) and underwater cleaning (UWC) at the berth or at anchor. In addition, we plan each dive around cargo operations, port regulations and the vessel’s departure time.
Underwater Hull Inspection and Cleaning Services
Underwater Hull Inspection (UWI)
Our divers inspect the hull plating, weld seams, rudder, propeller, sea chest gratings, anodes and other underwater fittings. They record the inspection with underwater CCTV and digital photography, so that you can review the condition from the office. Typical reasons for an inspection include:
- Checking damage after grounding, contact or a suspected impact
- Pre-drydock inspection to plan the repair scope
- Condition checks for charterers, owners or sale and purchase
- Inspection requested by class or Port State Control
Class-Approved In-Water Survey (IWS)
Where the vessel’s class rules allow it, an in-water survey can be carried out in place of a drydock bottom survey at the intermediate survey, or in support of a drydock extension. We arrange class-approved in-water surveys, carried out by a diving team approved for in-water surveys by ABS, Lloyd’s Register, Bureau Veritas, ClassNK and KR. During the survey, the divers inspect the hull, rudder, propeller, sea chests and stern tube seals with live video, while the attending surveyor follows the inspection from the surface.
Afterwards, the diving team issues its in-water survey report with photos and video. The attending surveyor then reviews the findings, and survey acceptance or any drydock extension remains subject to the class rules and the surveyor’s decision.
Underwater Hull Cleaning (UWC)
Marine growth on the hull increases resistance and fuel consumption. Therefore, we remove barnacles, weed and slime from the flat bottom and vertical sides with hydraulic multi-brush cleaning machines. We adapt the cleaning method to the hull coating and to local port requirements.
Propeller Polishing and Inspection
A rough or fouled propeller loses efficiency. We polish the propeller blades underwater to a smooth finish and, at the same time, inspect them for cavitation, cracks and bending.
Sea Chest and Cooling Water Intake Cleaning
Blocked sea chests reduce cooling water flow to the engine room. We clean sea chest gratings, intake valves and box coolers, so that the cooling systems receive enough sea water again.
Underwater Repairs
In addition to inspection and cleaning, our divers carry out repairs while the vessel stays afloat, for example:
- Sacrificial anode replacement
- Blanking of sea chests and overboard discharges for repairs inside the vessel
- Temporary hull patching and leak repair
- Underwater wet welding
- Rope and net removal from the propeller
Salvage and Recovery
We also recover lost anchors, anchor chains, equipment and other items from the seabed.
When You Need Underwater Hull Inspection and Cleaning
- Fuel consumption increase – hull or propeller fouling is reducing speed and raising fuel costs
- Before a charter or after a long idle period – heavy marine growth after the vessel has been at anchor for a long time
- After an incident – grounding, contact or a suspected hull leak
- Before drydock – planning the repair scope and steel work in advance
- Engine overheating – blocked sea chests or box coolers
How We Carry Out Underwater Work
- Enquiry – You send us the vessel details, the required work and the port and ETA.
- Permits and planning – We arrange the diving permit with the port authorities and plan the dive around cargo operations.
- Safety preparation – Before any dive, we agree the diving safety checklist and permit-to-work with the Master. The vessel confirms that the main engine, propeller, rudder, thrusters and sea suctions are isolated and locked out as required, and our dive supervisor confirms that conditions are safe to start.
- Diving operation – Our certified divers carry out the inspection, cleaning or repair, with live video to the surface where needed.
- Report – Finally, we issue a report with photos and video of the work and the condition found.
Where the work relates to a class item, we coordinate with the attending surveyor of the vessel’s classification society. However, acceptance of the findings remains the surveyor’s decision.
What You Receive After the Work
After each job, you receive a report with the findings, before and after photos and underwater video recordings. For hull cleaning and propeller polishing, the report shows the condition before and after the work. You can use the report for performance monitoring, charter requirements and repair planning.
Related Services
- Pier and Afloat Ship Repair Services – hull, machinery and steel repairs on board
- Marine NDT Services – thickness measurement and crack detection above the waterline
- LSA and FFE Inspection – inspection and servicing of life-saving appliances and fire fighting equipment
Ports and Anchorages We Cover
VNS provides underwater hull inspection and cleaning at ports and anchorages throughout Vietnam, subject to local diving regulations, permit approval and water conditions. For the full list of locations, see our Port Call Services page.
Northern Vietnam: Hai Phong, Cai Lan, Cam Pha Anchorage, Hon Gai Anchorage, Nghi Son, Vissai
Central Vietnam: Cua Lo, Vung Ang, Son Duong, Hon La, Da Nang, Dung Quat, Quy Nhon, Nha Trang, Cam Ranh, Vinh Tan
Southern Vietnam: Vung Tau, Cai Mep, Phu My, Ho Chi Minh City, Go Gia Anchorage
Selected Underwater Projects
For example, here is underwater work that VNS has completed on vessels calling in Vietnam:
- Underwater Ship Hull Cleaning
- Underwater Propeller Polishing
- Underwater Survey
- Diving and Underwater Inspection
Explore more ship repair projects completed by VNS.
Request a Quotation for Underwater Hull Inspection and Cleaning
So that we can prepare an accurate quotation, please send us:
- Vessel name, IMO number, vessel type and dimensions (LOA, breadth, draft)
- Port or anchorage and ETA / ETD
- Required work: inspection, hull cleaning, propeller polishing, sea chest cleaning or repair
- Date of the last hull cleaning or drydock, and photos if available
- Any class, charterer or PSC requirements for the report
VNS – Vietnam Ship Services Company
Head Office – Ho Chi Minh City
No. 8 Hoang Minh Giam Street, Ward 9, Phu Nhuan District, Ho Chi Minh City, Vietnam
Hai Phong Branch
213A Lach Tray Street, Ngo Quyen District, Hai Phong City, Vietnam
Phone: +84 869 655 569
Email: vietnamshipservice@gmail.com | vns.shiptech@gmail.com
