Design And Implementation Of Deep Well While-drilling Blowout Preventer Control System Based On RFID

Downhole blowout preventer is an important tool which can prevent the blowout in the process of drilling and ensure the safety of oil well operation. At present, the main control technology including mud-pulse, cables and metal ball. With the development of drilling in deep well and ultra deep well, downhole environment becomes worse, presented a challenge for the reliability, operability and automation level of controling of downhole blowout preventer. Based on the analysis of the deficiencies of the existing control system, a set of deep well blowout preventer control system is proposed based on RFID technology which can achieve the unlock control of preventer with high efficiency, high reliability and low cost. Main research results include:In order to satisfy the requirements of high reliability, good reusability and good operability,a control system with simple structure, convenient operation,reliable control, free data customization and low cost was proposed based on RFID technology to achieve the reliable control of blowout preventer. The influence mechanism of drill pipe, drilling liquid as well as their dynamic change along with the environment on RFID communication process were analyzed.RFID reader antenna was designed. The influence degree of drill pipe and drilling liquid on antenna of RFID reader was evaluated. Ferrite shield was added as an improvement strategy to block out the influence of metal and rules to be considered in shield ddesigning were given. This strategy effectively reduced the decaying-degree of internal magnetic filed and antenna inductance, blocked the influence on antenna caused by change of metal drill pipe outside.The principle of RFID adaptive communication technology which can implement dynamic tuning with real-time measurement and dynamic compensation was given and the frequencystable module was realized to overcome the dynamic interference caused by the change of drilling fluid configuration, change in temperature, and deviation of electromagnetic parameters or structure size of shield. These work ensure that the system works in the resonance state all the time and have greatly increased the reliability of communication and adaptability to environment of RFID control system.Finally the prototype system was implemented and tested. The test results showed that the combination of shield and frequency-stable module can effectively solve the influence of drill pipe and dynamic interference, and reliable unlock control of downhole blowout preventer was implemented. Prototype system was exhibited in The 15 th China International Petroleum & Petrochemical Technology and Equipment Exhibition as an important innovation of SINOPEC Petroleum Machinery Research Institute.