Design Of Measurement And Control System For Pressure Maintaining Transfer Of Drilling Core Samples

The exploitation of natural gas hydrate and the development of related technology and equipment are of great practical significance for improving the energy structure and solving the energy security problems in China.At present,the pressure maintaining sampling technology of natural gas hydrate in China has become mature,but the follow-up pressure maintaining transfer technology has not made great progress,which is not conducive to the further development of the follow-up research.In view of this situation,this project proposes and designs a set of measurement and control system of core sample pressure maintaining transfer device,which mainly includes two parts: the lower computer control system and the upper computer monitoring software.The embedded control system with stm32F429 as the core control chip has the functions of voltage conversion,data acquisition,motor control and network communication,and the real-time operating system Free RTOS is installed on the hardware platform can collect and read 4-channel pressure data,3-way temperature data,4-motor speed and torque data.Through TCP / IP protocol,it communicates with the host computer to realize data exchange,and controls the motor to complete the movement and cutting of core samples in high-pressure and low-temperature environment.The upper computer monitoring software based on.Net framework is responsible for real-time display and storage of the data uploaded by the embedded control system,and sends the core tube control instructions to the embedded control system to control the working process of the core tube.In addition,in order to ensure the safety and stability of the engineering application,researchers can judge the running state of the motor by observing the indicator light of the upper computer interface,and observe the dynamic display interface to master the long stroke movement and cutting process of the core tube.The whole set of measurement and control system and the mechanical part of the pressure maintaining transfer device have been jointly debugged in the refrigerated container of the wharf.Under the working environment of 25 MPa and 8?,a section of 3m long and 45 mm diameter core tube sample is cut into any length sample of 0.1m-1.5m.The results show that the measurement and control system designed in this project can realize the functions of automatic core grabbing,moving,cutting,calibration and transfer through the upper computer interface,which meets the requirements of the project design.