50results about How to "Avoid risk of sabotage" patented technology

A core dismounting and taking method of a complicated sand core comprises the following steps that an upper mold and a lower mold of a core box are manufactured according to a prefabricated model; a plurality of internal threads are formed on the upper mold, sand is fed into the sand box from a sand feeding opening, the sand is compacted while being fed, and after sand feeding is completed, the sand feeding opening is scraped to be flat; the sand core is hardened; the sand core is dismounted; and the sand core is taken. According to the core dismounting and taking method of the complicated sand core, the internal threads are arranged on the upper mold, a plurality of matched threaded rods are adopted, and the upper mold is lifted in the vertical direction through the reactive force of a parting surface of the lower mold on the threaded rods and the engagement force between the threaded rods and the internal threads until demolding is achieved; and in this way, the upper mold is controlled to be lifted in the vertical direction through the threaded rods, the left-right shake risk is avoided, and the risk that the sand core of a complicated-shape structure is damaged is fundamentally eradicated.

The invention discloses a method for arranging a vibration suppression device of a variable-pitch marine riser, which comprises the steps of: firstly, according to the actual sea conditions and the inherent characteristics of the riser, the vortex-induced vibration fatigue analysis is carried out on the riser, and according to the analysis result, it is determined whether the installation is necessary Suppression device for vortex-induced vibration; in the second step, according to the vortex-induced vibration fatigue damage risk level, vibration amplitude and drag force load of the riser, the riser is divided into high-risk section of fatigue damage, low-risk section, no-risk section and transition Section, and then adopt different preset installation methods to arrange the vibration suppression device, and finally complete the arrangement of the vibration suppression device. The invention divides the axial area of ​​the standpipe into a high-risk section of fatigue damage, a low-risk section, a no-risk section and a transition section, and adopts different spacings to arrange vibration suppression devices in different fatigue damage areas. This arrangement method can ensure the suppression effect of the vibration suppression device on the vortex-induced vibration, and greatly reduce the drag force load on the standpipe.

A core dismounting and taking method of a complicated sand core comprises the following steps that an upper mold and a lower mold of a core box are manufactured according to a prefabricated model; a plurality of internal threads are formed on the upper mold, sand is fed into the sand box from a sand feeding opening, the sand is compacted while being fed, and after sand feeding is completed, the sand feeding opening is scraped to be flat; the sand core is hardened; the sand core is dismounted; and the sand core is taken. According to the core dismounting and taking method of the complicated sand core, the internal threads are arranged on the upper mold, a plurality of matched threaded rods are adopted, and the upper mold is lifted in the vertical direction through the reactive force of a parting surface of the lower mold on the threaded rods and the engagement force between the threaded rods and the internal threads until demolding is achieved; and in this way, the upper mold is controlled to be lifted in the vertical direction through the threaded rods, the left-right shake risk is avoided, and the risk that the sand core of a complicated-shape structure is damaged is fundamentally eradicated.

The invention belongs to the technical field of oil and gas field drilling and completion, and in particular relates to a radial horizontal drilling and sand control completion tool and method, wherein the tool is characterized in that it includes a radial horizontal drilling auxiliary string, a radial horizontal drilling tool string and a sand control tool , radial and horizontal drilling auxiliary strings include depth adjustment tools, special tubing assemblies, depth calibration tools, azimuth determination auxiliary tools, axial anchoring tools, azimuth adjustment tools and drilling steering tools, and radial horizontal drilling tool strings Including interconnected logging cables, circulating liquid inlet tools, gravity sealing tools, circumferential anchoring tools, power motors, variable buckle joints, flexible drill pipes and milling bit tools. The invention can establish a 10-20m (hard formation) stable drainage channel between the wellbore and the oil layer, replace the conventional perforation for deep penetration completion, cross the near-well pollution zone, penetrate the oil well invasion zone, and improve water injection wells, Injection rate of gas injection well and treatment well.