Project Full Name：Popularization of Managed Pressure Technology in the Whole Process of Drilling, Logging, Cementing and Completion

Company：CCDC Drilling & Production Technology Research Institute

Awarded：Cost Reduction & Efficiency Enhancement Technology

Standeard:  International Advanced Level

Projec Number：ECF-2021-SET-1007

Principal Accomplishers： Yang Bo, Li Zhilin, Zuo Xing, Li Sai, Xie Hongbing, Ren Wei, Shu Mei, Chen Zhaoxi, Tang Ming

Chuanqing Controlled Pressure Drilling System

Key Innovation Points：

• The core theory and method of wellbore pressure safety control for managed pressure drilling and completion are constructed, and the technical bottleneck of active, accurate and safe control of wellbore pressure is overcome. The wellbore pressure calculation error is reduced from more than 10% to less than 5%, and the leakage is found 5-10min in advance.

• A complete set of equipment for managed pressure safety drilling and completion is invented, which fundamentally solves the problem that it is difficult for conventional drilling to accurately control pressure, which finally induces blowout. Compared with foreign products, the wellhead casing pressure control accuracy of the equipment is improved from ± 0.15MPa to ± 0.07MPa, and the response time is reduced from 6 ~ 8s to 2 ~ 3s.

• Managed pressure technology in the whole process of drilling, logging, cementing and completion is established, which overcomes the worldwide problem of "high risk, failure to drill and poor cementing quality" in deep complex formations, and realizes the safe tripping in and out more than 3000 times. The average cementing acceptance rate of gas reservoir is increased from 39.6% to 91.6%, and the wellhead pressure condition rate in the gas production well is reduced from 39.24% to 6.98%.
  

Main Application and Technical Principal： 

A set of managed pressure drilling system with micro flow and bottom hole pressure as the control objectives is designed and developed by using the modular and combined strategy DCS mode. 

Through analyzing, processing and issuing the bottom hole pressure data is measured by the annulus pressure monitoring system and the engineering parameters and system equipment parameters collected by the monitoring and controlling system in real time，the managed pressure control drilling system sends out pressure control decision-making instruction to the automatic throttling control system and back pressure compensation system to automatically and accurately control the wellhead back pressure, so as to realize the closed-loop accurate control of bottom hole pressure, and effectively solve the world-class problems of enormous drilling difficulty, poor cementing quality and high well control risk in the deep and ultra-deep formation where the narrow safety density window is usually encountered.