Abstract: The annulus pressure buildup (APB) in deepwater oil and gas wells may not be released even by employing a casing annulus resulting in accidents, such as casing collapse. Therefore, it is necessary to regulate the APB to ensure safety during oil and gas production. This study has calculated the trapped annular pressure in deepwater wells under different temperatures and analyzed and optimized the method to prevent and control the annular pressure in these wells. Using the strength standards for casing strings, this study has proposed a method to verify the strength of the casing string in the deepwater well and established a pressure management method for the trapped annulus. In terms of deepwater oil and gas wells, the control method for the trapped annular pressure involves relieving the pressure of the A-annulus through the formation pressure relief and wrapping the casing strings with compressed foam. The strength of the casing string must be verified using both equilibrium and nonequilibrium methods concerning the trapped annular pressure; the prevention and control methods must be considered together with these verification results to determine the pressure control range for the trapped A-annulus.

Key words: deepwater well, APB, control methods, casing strength, verification method