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How to Perform Ship’s Stern Tube Integrity Test in The Dry Dock? The intention behind sending a ship to the dry dock at regular intervals of time is to inspect those parts which are technically difficult to access when the ship is at sea. One of the systems that is inspected during dry docking is the ship’s stern tube system, which carries the propeller shaft turned by the engine’s intermediate shaft, a configuration that propels the ship in the desired direction. During dry dock, the stern tube is opened up for inspection of the seals, the stern cylinder, and the shaft. Overhauling and replacement of seals are done if their condition is not as per maker’s desire. After overhauling and boxing back the stern tube system, the next step is to make sure that it does not leak oil out to the sea or water inside the engine room, once the ship is water bourn. For this purpose, post overhauling inspections are carried out in the dry dock by experience ma...

Choosing A Marine Boiler While Designing A Ship Marine boilers used in ships today are mostly for auxiliary purposes in vessels that run on marine diesel engines or diesel electric propulsion. In case of ships using steam turbines (mostly found in high speed vessels used by navies), boilers are a part of the main propulsion system. However, in this article, we will focus on auxiliary boilers, i.e. boilers used for running auxiliary systems in a ship. To look at this from a ship designer’s point of view, he/she should be able to choose the right kind of boiler for a particular ship depending on the requirement for that particular project. The process is pretty much an application of first principles, but in a somewhat different way. To rate a boiler, one first needs to correctly estimate the steam output required from a boiler for the ship being designed. For this, the three main requirements are: Requirement 1  – Steam consumption required to compe...

8 important points for inspection anf maintenance of ship's engine room crane. Whether it’s overhauling of main engine/ machinery or shifting of heavy parts, the engine room crane is regularly used for “heavy-duty” jobs, which are usually beyond the physical capabilities of the engine room crew. Th engine room personnel are qualified to operate the crane in a safe manner but as a machinery, the crane is subjected to breakdowns if proper maintenance and care is not taken. The scenario can be worse if the crane fails in the middle of lifting the load or while carrying out important machinery overhauling. As a responsible officer on ship, the engineers using the crane must do regular inspection and scheduled maintenance to ensure the crane works safely without giving up at all times. The engine room crane has a Safe Working Load (SWL) limit, which should never be crossed at all times. The crane manual is the best source to understand when...

8 important points to note for maintenance of emergency generator on ship. Any kind of emergency equipment or system provided onboard is an important lifeline for the ship and its crew when faced with an emergency situation. Emergency Generator is without doubt one of the most important equipment on board, which is responsible for preventing accidents and grounding during power failure while the ship is in heavy traffic, channels, rough weather or in manoeuvring. The Emergency Generator on ship comes into play as back up  source of power  when the main generators fails to provide the necessary power to the engine room and other deck machinery systems. Considering its high importance, the emergency generator is required to be tested regularly along with carrying out all important planned maintenance jobs as per schedule. This would not only ensure smooth running of the emergency generator but would also avoid breakdown when the ship is already facing a ...

oily water seperator (ows) maintenance tips. Every engineer on ship knows the importance of oily water separator (OWS) and must have heard stories of legal actions taken against seafarers who tried to fiddle or bypass the automation system of the OWS. The most common cause of people tempering with oily water separator is deterioration of performance of the system. Apart from the filter getting clogged due to continuous usage, there can be many other reasons for the lack of performance. A few critical points, which are often ignored and less commonly known to engineers operating oily water separator on daily basis, are discussed in this article to ensure efficient performance of oily water separator (coalesce filter type) used onboard ships: 1. Oil In Bilge:  The separator is suitable for separating small quantity of oil in bilge and not the other way round. If there is a mixture consisting of small quantity of water...

Understanding ship fin stabilizer and its operation. The function of a fin stabilizer, found at the bottom part of the ship’s hull, is to provide resistance to the excess rolling of ship in either direction. Many seafarers have not seen a real fin stabilizer until the ship goes to dry dock for hull inspection and surveys. This does not rule out the knowledge that every onboard engineer and officer must posses regarding the components and functioning of fin stabilizer system. Let’s take a look at the main components of fin stabilizer of ship. Components: 1. Two fins  forming part of the hull structure of the ship, one port and one starboard. These fins are connected to fin stabilizer room on port and starboard sides of the ship from where they are operated/ controlled Each stabilizer consists of a fin box, which houses a fin and supports the fin actuating machinery. Each stabilizer machinery unit provides the support and the means by which the fin ma...