In Ro-Ro ship carrying heavy cargoes, it is very important to maintain a certain level of aft draft and the proper trim through the entire loading or discharging process. Some kinds of manual ballast control system have been generally applied so far to this practice in Ro-Ro ship. However, there is need to develop a so-called Auto-Trim Control System using some computer technology to improve the operation of those existing systems.
This paper aims at developing an Auto-Trim Control System especially for Ro-Ro ship carrying such heavy cargoes including hot coils and steel plates. The author carried out some systems analysis and design for developing the system by examining and reflecting the practices of the entire loading and discharging process.
Then a user-friendly Auto-Trim Control System has been built by interfacing the Valve Remote Control system and Tank Level & Draft Measuring system with itself. The author also provides some excellent results on the performance of the system by reporting the records of installing the system on board 4 Ro-Ro ships.