The Research Of Jack-up Hydraulic Loading Monitoring System

Underwater oil storage tank is installed at the bottom of multifunctional jack-up, whichensures its efficiency and therefore makes it suitable for the development of marginal field. Itworks by the way of oil and water replacement. During the whole process of replacement, thecondition of the oil tank should be strictly monitored, including temperature, pressure andliquid measure. When emergency occured, the tank should be closed, lest that oil leakagepollute the ocean. The paper presents a closed-loop DCS in accord with the condition of theoil tank and then analyzes the sensors installation position and reliability of the system.Introduced practical application range of the system and comes up with a new design ofDCS with485field bus included, which can enhance the anti-jam capability of the system.The data acquisition system has been also redesigned with single chip microcomputer for dataacquisition and host computer for data storage and processing. Besides, the paper shows howthe hardware should be redesigned to ensure the closed-loop control.As many sensors are required in real time monitoring system, this paper suggests a moreefficient location of the sensors. Multipoint monitoring system is used to monitor thetemperature, pressure and so on. By the FLUENT simulation the law of heat transfer can begained: how the temperature of the fixed point varies with time. The aim of the redesign ofthe sensor location is to reduce the number of monitoring points and required sensors underthe condition that the monitoring data can reflect the temperature variation exactly.The reliability of monitoring system is the foremost parameter and directly influences thesafety of the system. This paper has analyzed the reliability of both the software and hardwareof the monitoring system. Based on Markov process, the paper gives detailed analysis of thereliability of the hardware, and shows how reliability changes in accord with availability andmaintenance time and hence gives theoretical basis for the improvement and selection ofhardware. In addition, the monitoring system also equipped with anti jamming measurement.As the monitoring system is developed by VB, it can function independently as a hostcomputer system, disengaged programming environment. The monitoring system has thefunction of data acquisition, processing and real-time curve drawing, as well as historical data inquiry. Testing system is also designed to conduct experiment for the installation of both thehardware and software.The paper has presented DCS monitoring system suitable for underwater oil storage tank.Not only applicable to multifunctional platform, it can also lay the theoretical foundation forthe future development of multifunctional platform monitoring system. And the valuableexperience has great guidance significance for future study and the result fills the vacancy inthis industry in China.