【摘要】 天然气水合物研究中急需解决的问题是水合物勘探和开采时钻井内的热力学特征以及相应的钻井技术。研制了水合物综合模拟实验系统,以研究水合物形成和分解的热力学和动力学特性、井内热压力分布规律以及相应的水合物钻井技术等。由于实验持续时间长、压力高、环节多,为减轻劳动强度和保证实验安全,在实验系统中增加了控制模块。PCI-1711多功能卡为控制模块的核心,采用OMRON/G2R-1型继电器控制系统设备的关停,系统可实现自动超压保护。通过接口转换模块连接微机和控制器,在微机上对可编程高低温实验箱进行控制,流量比例阀和步进电机分别用来控制微钻模块中的钻杆升降和转速。整套控制模块已在水合物合成及钻井液模拟实验中得到了成功应用,系统运行稳定,超压保护灵敏,大大减轻了实验强度并增强了实验安全性。更多还原

【Abstract】 Natural gas hydrates are taken as an alternative energy for the 21st century and have become the hotspot of the present geosciences and energy research.The Synthetic Experimental System of Gas Hydrates Mini-Drilling Simulation(SESGHMDS)was built up to study the thermodynamics and kinetics of gas hydrates formation and dissociation,distribution characteristics of temperature and pressure in gas hydrate well drilled for exploration and exploitation,and gas hydrate drilling technologies.A control module was developed to lighten labor intensity and guarantee experiment safety in the SESGHMDS.A multi-function card PCI-1 711 was selected as the core of the control module,which has high-speed data acquisition and digital/analog output.A relay OMRON/G2R-1 was used to automatically manage the startup/stop of units.A solenoid valve VP542 and a gas-control valve NV1-20-6M-ATC were used to operate overpressure protection.PLC TEMI550 was used to control programmable high-low temperature test chamber HLT705P through connecting it to a computer using a RS232/RS485 converter I-7520.A proportional valve and a stepper motor were used to control lifting and rotary speed of the drilling pipe in mini-drilling module.The corresponding software is coded by using multithreading and Visual C++6.0 language.It has good quality on interface,maintainability and expansibility.The whole module are operated successfully in the experiments of gas hydrates formation drilling fluids simulation test.It works steadily,executes quickly and has high sensitivity for overpressure protection,which largely lightens the experimental intensity of the labor and enhances the safety of the experiments.更多还原