Abstract: A method for offshore dual-drive core drilling with three layers of casings under surge compensation is provided. According to the method, a drilling vessel is located at set latitude and longitude coordinates by a dynamic positioning system; drill pipes are stabilized by a seabed template; torques and drilling pressures can be transmitted during drilling of the casings by means of surge compensation of the casings at a wellhead; during drilling for sampling, the surge compensation can compensate to a certain extent for a change in water depth caused by rising or falling tides, or surge, thereby preventing the casings from colliding with equipment and ensuring the safety of wellhead operation; and the drilling of three layers of casings is achieved by means of dual driver heads to effectively protect a wellbore wall, such that high core-drilling rate and good core-drilling quality are achieved during drilling for sampling.

Abstract: A method for offshore dual-drive core drilling with three layers of casings under surge compensation is provided. According to the method, a drilling vessel is located at set latitude and longitude coordinates by a dynamic positioning system; drill pipes are stabilized by a seabed template; torques and drilling pressures can be transmitted during drilling of the casings by means of surge compensation of the casings at a wellhead; during drilling for sampling, the surge compensation can compensate to a certain extent for a change in water depth caused by rising or falling tides, or surge, thereby preventing the casings from colliding with equipment and ensuring the safety of wellhead operation; and the drilling of three layers of casings is achieved by means of dual driver heads to effectively protect a wellbore wall, such that high core-drilling rate and good core-drilling quality are achieved during drilling for sampling.

Abstract: The present invention discloses an optimization method for a screen surface dynamic load of a vibrating screen. The method includes the following steps: step 1. selecting design variables, and establishing an experimental matrix; step 2. performing a response curved surface experiment; step 3. establishing two double-objective optimization models and solving the same to obtain two groups of Pareto solution sets, wherein the solution sets respectively represent screening efficiency optimization paths of the vibrating screen under the conditions of a high screen surface dynamic load and a low screen surface dynamic load; and step 4. calculating an optimization space for a screen surface dynamic load under a high screening efficiency. According to the method of the present invention, the screen surface dynamic load can be directly reduced, and the service life of the screen surface and the whole vibrating screen is prolonged.

Abstract: The present invention discloses an optimization method for a screen surface dynamic load of a vibrating screen. The method includes the following steps: step 1. selecting design variables, and establishing an experimental matrix; step 2. performing a response curved surface experiment; step 3. establishing two double-objective optimization models and solving the same to obtain two groups of Pareto solution sets, wherein the solution sets respectively represent screening efficiency optimization paths of the vibrating screen under the conditions of a high screen surface dynamic load and a low screen surface dynamic load; and step 4. calculating an optimization space for a screen surface dynamic load under a high screening efficiency. According to the method of the present invention, the screen surface dynamic load can be directly reduced, and the service life of the screen surface and the whole vibrating screen is prolonged.