Ship-Maintenance Underwater (SMU) is a Danish diving service company in the world that performs all kinds of boats ship service tasks and diving service tasks.

Should you have clarified a task far or you must have understood what options are available? So we are always ready with advice and guidance. We have extensive experience in solving special tasks and we are always ready to develop a solution for you, no matter what challenge you are faced with.

SMU promote development in the Danish diver service industry

When we were not out diving service tasks in Danish ports or offshore in Danish waters, we are at the drawing board, where we are constantly working to develop new methods to improve the diving service industry. We do this to ensure that our customers always get the best, most effective and most gentle solution to the benefit of both customers and the environment.

Among others we have developed a filter system which means that we are the only ones to carry out screw polishing in both Copenhagen and Aarhus’ docks, under the current environmental requirements. As well as an innovative, ROV-based hull cleaner for the maritime diving service environment.

As Danish diving service company we are incredibly proud to help promote the industry’s development, and we will also continue to pave the way for new solutions and methods, as Denmark continues to emerge as a pioneer in the diving service.

tel:+45 28495759



The effectiveness of the ship's screw would determine drag and fuel consumption of the vessel. Therefore, our team is able to deliver the highest standards of screw maintenance for shipping companies and vessel owners by ensuring that cavitation wear avoided / worsens, and to achieve savings. S.M.U performing propeller polishing on all types and sizes of vessels in all Danish ports and offshore. We may be the only company in the Nordic region, achieving a surface roughness at the screw polishing, there are far better than Rubert Gauge "A" (the best result with a Rubert Gauge "A" is 1.00 micron Ra (CLA) and we can polish the surface down to a roughness of 0.40 micron Ra (CLA)). By getting carried screw polishing can achieve the following benefits: Up to 4% fuel savings, depending on the fouling of the propeller. Lower load of the main engine. Reduced CO2 emissions resulting from fuel savings. Propeller polishing performed under water, giving a better result than polishing in dry dock.


We provide hull cleaning of all types of vessels of all sizes and in all Danish waters. We can carry out cleaning with two different systems: An innovative and innovative hull cleaning system, operated from the surface. The system was developed and patented by SMU in 2013. The system is both more gentle on the ship's surface and the environment, and it is far more efficient than conventional systems. This is because the system does not require divers and that it can clean a larger area faster. ROV system is suitable for vessels of over 250 m. LOA. System 2 is a conventional brush system which is operated by divers in the water. We offer different types of brushes, depending on the vessel surface and fouling. Brush system is particularly good for hull cleaning of ships of less than 250 m. LOA.

SKIBSSURVEY (class survey)

An in-water survey is when one makes a diving inspection of a vessel's structure under water. We carry out both planned surveys, for example. in combination with a classification, and acute inspections, for example. may become necessary as a result of the grounding. The inspection carried out by a diver who inspects the vessel thoroughly. If there is a classification inspection also requires a supervisor and a surveyor from the classification. Once we have completed an in-water survey both you, and possibly. classification society, receive a diver video (CCTV), a report and, if necessary. other documentation of your choice.


Here at S.M.U. we perform professional Photo and video inspection, and provide documentation requested by the customer. If the customer wants it delivered image documentation in a detailed report. We carry out both planned underwater Photo inspections, for example. in combination with a classification, survey, sediment / soil conditions, sprinkler tanks, Underwater construction both before and after diving. As well as acute inspections, for example. may become necessary as a result of grounding or damage to port facilities, submarine cables or pipelines. Several of our customers take advantage of us to inspect the work of other divers, as well as to document and advise on the future projects.


We can perform thickness measurement to steel structures such as steel sheet pile. The results found are delivered to the customer in a detailed report.



We have here with S.M.U. many years of experience with the installation of anodes on the quay, poles, ships and steel constructions. We perform both new installation and replacement of anodes, although it is as a subcontractor or complete contract, for companies, contractors or the public. S.M.U. advise and inform customers like about Cathodic protection, and if desired provide a quote.


We have many years experience in molding and building molds below sea level. So whether it comes to casting of sheet piles, molding piles, or other molding operations, we are always able to solve the task and are always available for life to solve molding operations, quickly and safely.


We are at S.M.U. very proud of our skills in underwater welding, where we always deliver the best possible result. We have over the years welded subjects in most applications, so are therefore able to perform all kinds of welding applications.


We are cutting electrodes, oxygen and custom built underwater equipment cutting steel with great efficiency


We have much experience in setting up base security in ferry berths. We ar both cast-base and zoned gabionger.


At SMU, we have experience in diving operations at slipways. We inspect, repair slipways and install anodes. Additionally flusher we beddings rails free of sand and sediment, so the operation of the pipeline can be resumed.



S.M.U. welcomes visitors on tasks as the main contractor for both small and large tasks. We have experience and expertise to handle all aspects of a contractor job.


S.M.U. has repeatedly advised customers before, during and after diving. We can among others. Advise on opportunities, security, economy and duration. We advise and inspect other dive companies work after a completed task as part of quality assurance.


We can offer an effective solution for cutting concrete, which through. A sub-contractor can cut through large items concrete using a wire saw. The saw can be modular so there is almost no limit to the size or thickness of the items to be cut.


At SMU, we have several years of experience in conducting inspections of tank systems and sprinkler tanks in the industry. After all tank inspections, we deliver detailed status report on our findings, as well as video documentation to the customer's future needs.


S.M.U. comprises a hammer drill machines both hydraulic and pneumatic built for use in salt water, so we can drill holes in concrete and stones at customer's wishes.