Tillståndsbaserat underhåll - ubåt A26

Abstract: This project is a study that has described what condition based maintenance is and has examined the possibilities with condition based maintenance on the new A26 submarine. It finishes with a detailed case study of how a condition based maintenance system could look like on the submarine’s diesel engines. Questions that have been answered are; what is condition based maintenance and how does it work? What are the possibilities to install a condition based maintenance system on the new A26 submarine? What has to be considered? What exists on the A26 submarine already that can be used and what has to be added for such a system to work properly? Condition based maintenance is a maintenance strategy that aims to optimize the overall maintenance plan. This is done by analyzing the machine health by making different kinds of measurements on the machine, e.g. vibration measurements, thermography, ultrasonic measurements, oil analysis etc. The measured values are then analyzed either by an advanced software program or a technician that can determine when the machine will break down and plan the correct maintenance action at the optimal time. To be able to do this one need to know what the expected levels are for the measured property for the current run mode, what the critical levels are, and how various errors develop. On board the A26 there is a Ship Control and Monitoring System (SCMS) which is a system for controlling and monitoring everything on the ship. This system, with its I/O-modules spread out throughout the ship, can be used to a great advantage. It is relatively easy to add new sensors to it and store measured data on board the ship. This makes a permanently installed system very appealing, although some systems might benefit from a round based system. To analyze all the acquired data an analysis program should be installed on the SCMS. If this program should be developed internally at Kockums or if it should be bought from an external supplier still needs further investigations. A detailed study of what a condition based maintenance system could look like has been made on the diesel engines. On a Scania marine diesel engine there are already a lot of sensors that monitor useful information. However, that information is not considered enough to make a complete satisfactory machine health diagnosis. To be able to pinpoint most possible failures it has been found that vibration monitoring combined with oil analysis with a permanently installed system is probably the best solution. For that, sensors monitoring vibrations and oil condition need to be added.