Research on high-temperature test devices and test methods for blowout preventers using water media

Abstract

Reliability verification of blowout preventers (BOPs) in oil and gas drilling and production equipment is difficult under extremely high-temperature and high-pressure conditions, such as deep wells and ultra-deep wells. Traditionally, oil-based media are used for testing. However, because the temperature fluctuation of oil-based fluid is very intense, it will have a significant impact on the test pressure, which not only increases the complexity of operation but also significantly reduces the credibility of the results. Therefore, this paper presents a special physical test device for high-temperature tests of blowout preventers, using water as the working medium. The device supports a maximum simulation temperature of 350 °C, a pressure range of 0–250 MPa, a pressure control unloading system, and an automatic displacement device. Through the combination of experimental measurement and numerical simulation, the variation law of the volume expansion modulus of water within a certain range is systematically revealed. The problem of water phase change at high temperature (310 °C) is also solved. On this basis, the "segmented temperature control-pressure real-time compensation" high temperature and high pressure control strategy is designed, and a complete simulation test scheme is formulated in combination with the actual working conditions. The results show that the phase change caused by the volume expansion of the water medium at high temperature can be effectively controlled by the test device. The test process is stable, the data is accurate, and both the reliability of the test system and the effectiveness of the test method are demonstrated. The reliability of the test system and the effectiveness of the test method. This study opens up a new direction for the high-temperature testing of BOPs and holds significant importance for ensuring the efficient and safe operation of BOPs.