国产精品熟妇视频国产偷人,色偷偷av一区二区三区,久久久亚洲欧洲日产国码aⅴ ,丰满的少妇愉情hd高清果冻传媒

As deep and high-risk exploration wells such as ultra-deep wells are being developed, these wells have characteristics such as deep burial depth, high pressure coefficient, high single-well design output, and high fluid temperature at the wellhead. These ultra-high pressure wells have a completion depth of over 8,000 meters, a formation pressure exceeding 180MPa, a formation temperature of up to 170°C, and an expected shut-in pressure of over 150MPa. The wellhead devices are required to have ultra-strong load-bearing capacity, ultra-reliable sealing ability, ultra-fast shut-in ability, and an ultra-safe system design. By designing high-strength load-bearing steps and ultra-reliable sealing ability to meet the requirements of load-bearing and 210MPa gas sealing pressure, and by using a unique shear-type safety valve, the well can be shut-in quickly within 5 seconds, with a design life of at least 30 years