7results about How to "Guarantee cementing quality" patented technology

The application provides a one-way sealing ring, a sealing mechanism, a tail pipe top packer and a tail pipe cementing process, wherein the one-way sealing mechanism comprises a center pipe, an upper deformed sleeve arranged on the outer wall of the center pipe, a lower deformed sleeve arranged on the outer wall of the center pipe, the upper deformed sleeve and the lower deformed sleeve being spaced apart in the axial direction, a sealing element arranged on the outer wall of the center pipe, the lower end of the sealing element being in abutment with the upper end of the lower deformed sleeve, an expansion cone arranged between the upper deformed sleeve and the sealing element, a sealing groove being arranged on the inner wall of the expansion cone in the circumferential direction, a sealing ring being arranged in the sealing groove, a flow-off groove being arranged on the inner wall of the expansion cone in the axial direction, the flow-off groove penetrating through the upper end and the lower end of the expansion cone, and fluid being allowed to flow only in one direction from the upper end of the expansion cone to the lower end of the expansion cone along the flow-off groove, while the fluid under the packer is allowed to flow upward, the wellhead annulus is allowed to be pressurized for cement setting, the pressure reduction caused by volume shrinkage is prevented to prevent the stratum fluid from flowing out, and the cementing quality is ensured.

The invention discloses a preparation method of a modified PBO fiber toughening agent for well cementation under a high-frequency alternating injection-production condition, and belongs to the technical field of well cementation materials. The method comprises the following steps: obtaining PBO fibers; the method comprises the following steps: soaking PBO fibers in an acetone solution, cleaning and drying; weighing heavy calcium carbonate, ethanol, a silane coupling agent and deionized water, mixing and stirring to obtain a modified solution; pBO fibers are added into the modification solution, the mixture is placed in a magnetic stirrer to be stirred at a high speed for 30-90 min, and primary modified PBO fibers are obtained; and putting the primarily modified PBO fiber into a beaker containing deionized water, putting the beaker into an ultrasonic cleaner, and treating for 20-40 minutes to obtain the modified PBO fiber toughening agent. According to the present invention, the raw materials are cheap and easily available, the preparation process is controllable, the product performance is stable, the compatibility is good, and when the cement paste is used for the well cementation operation, the formation environment and the working condition faced by the air energy storage well can be met, and the success rate of the well cementation construction can be improved.

The invention relates to cement paste with high bonding strength and low density as well as a preparation method and application of the cement paste. The cement paste with high bonding strength and low density is prepared from the following components in parts by weight: 100 parts of G-grade cement; 5-40 parts of a lightening agent; 1 to 15 parts of micro silicon; 1-5 parts of a fluid loss agent; 0.5-5 parts of a drag reducer; 1-5 parts of a resin emulsion; 0.1 to 2 parts of a retarder; 0.1 to 0.2 part of a defoaming agent; and 50 to 120 parts of water. The invention aims to solve the problem of improving the density range of the cement paste and the cementation capability of set cement on the premise of not influencing other properties of the paste by matching various materials.

The invention discloses a cement paste thickening duration determination method and device, equipment and a storage medium, and belongs to the technical field of petroleum drilling engineering. The method comprises the following steps: acquiring a first consistency value of first cement paste under a first preset condition and a first duration corresponding to the first consistency value, acquiring a second consistency value of the first cement paste under a second preset condition and a second duration corresponding to the second consistency value, and calculating a duration difference value corresponding to the equal consistency value when the first consistency value is equal to the second consistency value, and optimizing the first thickening time length of the first cement paste based on the time length difference value to obtain a second thickening time length. The second time length is obtained under the condition of temperature and pressure change, so that the time length difference value can reflect the influence on the thickening time length when the temperature and the pressure change. Therefore, in the embodiment of the invention, the influence of temperature and pressure changes on the thickening time of the cement paste is considered, and the accuracy of the thickening time of the cement paste is improved, so that the anti-channeling capability of the cement paste is effectively improved, and the well cementation quality of an oil-gas-water layer is ensured.

The utility model belongs to the casing cement float collar float shoe technical field, and disclose a kind of casing cement float collar float shoe, including the upper end surface of casing float collar body is equipped with the float shoe device fixedly, the upper end surface of float shoe device is equipped with nickel-titanium alloy column framework fixedly, the inside of nickel-titanium alloy column framework is equipped with honeycomb deformable framework fixedly, the inside of honeycomb deformable framework is equipped with memory polymer fixedly, by nickel-titanium alloy column framework, honeycomb deformable framework and memory polymer, utilize nickel-titanium alloy telescopic characteristic and make float shoe adapt to different working conditions, honeycomb deformable framework enhances structural stability and adaptability, memory polymer outer layer accurate recovery shape plays the protection and sealing effect, guarantee well cementing quality.

The application provides application of a modified starch-based material in retarding of a high-temperature oil well cement system, and belongs to the technical field of oil well cementing cement. Octenyl succinic anhydride modified starch is added to the oil well cement slurry system, wherein the addition amount of the octenyl succinic anhydride modified starch is 0.1% to 2.0% of the cement mass. The modified starch is added to the oil well cement slurry system in an amount of 0.1% to 2.0% of the cement mass, can effectively delay the cement slurry thickening process under the high-temperature cementing condition of 90 to 150 DEG C, keep the thickening curve stable, reduce the risk of abnormal gelation, and has little adverse effect on the rheological property of the cement slurry and the mechanical property of the cement stone in the later period. The modified starch material is derived from renewable natural polymer resources, has the characteristics of environmental friendliness and stable retarding effect, and is suitable for cementing operation of deep and ultra-deep oil and gas wells.

The invention discloses a well cementation method and a well cementation system suitable for a surface casing interpolation method. The well cementation method and the well cementation system solve the problems that an existing well cementation method is inconvenient to operate, low in production efficiency, high in cost and prone to slurry mixing. The well cementation system comprises an underground part and an overground part, the underground part comprises a guide pipe inserted into a well wall stratum and a surface casing string inserted into a well, and the overground part comprises a cement supply system and a drilling fluid circulation system. According to the method, the drilling fluid is injected firstly to stabilize the flow, then the cement paste is injected, and finally the drilling fluid is injected to replace the cement paste in the drill rod string. The method is easy to operate, the length of the cement plug can be controlled, slurry mixing is avoided, and the well cementation quality is good; the system is simple, easy to operate and low in production cost and equipment cost.