Abstract: A reactive torque automatic balancing device for a screw drilling tool includes an upper joint (1); a core cylinder (9) having an inner chamber in communication with the screw drilling tool (305) located downstream, so that drilling fluid from the inner chamber of the upper joint (1) flows to the screw drilling tool (305) through the inner chamber of the core cylinder (9) to allow the screw drilling tool to perform drilling; a lower joint (16) fixedly arranged at a lower end of the core cylinder (9); and an automatic balancing assembly, which is arranged between an outer wall of the core cylinder (9) and an inner wall of the upper joint (1), and driven by hydraulic pressure generated by a part of the drilling fluid flowing through the inner chamber of the upper joint (1).

Abstract: The present invention provides a downhole auxiliary drilling apparatus, including an impact energy generator capable of converting the energy of the drilling fluid to the axial impact energy, and an impact energy distributor capable of redistributing the impact energy generated by the impact energy generator to convert the axial impact force into a combined impact force, which provides the drilling bit with a high-frequently changing combined impact force, thus greatly improving the rock breaking efficiency and the rate of penetration of the drilling tool. The downhole auxiliary drilling apparatus is further provided with a shock-absorbing and torque-stabilizing device arranged between the impact energy generator and the impact energy distributor, which can reduce the axial vibration of the drilling tool and the damage on the drilling bit, and greatly extend the lifetime of the drilling bit.

Abstract: A random copolymer, a preparation method of the random copolymer, a drilling fluid containing the random copolymer. The random copolymer contains structural unit (A) represented by formula (1), structural unit (B) represented by formula (2), structural unit (C) represented by formula (3), and structural unit (D) represented by formula (4) or (5): wherein X is halogen. When the random copolymer is used as a filter loss reducer in a high-calcium drilling fluid, the filter loss of the high-calcium drilling fluid can be reduced.

Abstract: A resistivity measurement while drilling (MWD) device, including: a transmitting module arranged on an outer surface of a drill collar, for generating an induced current between the drill collar and surrounding formation by inductive coupling; a receiving electrode group including at least two electrodes, for receiving a measured current that reaches the electrode from the induced current through corresponding formation, two electrodes in the receiving electrode group being multiplexing electrodes; a resistivity calculation module configured to be connected to all or a part of the electrodes in the receiving electrode group in a measurement mode of the resistivity MWD device, to calculate the measured current received by a corresponding electrode and obtain resistivity of formation corresponding to the corresponding electrode; and a data transmission module configured to be connected to the multiplexing electrodes in a transmission mode of the resistivity MWD device, for transmitting calculated resistivity to

Abstract: A maleamic acid monomer, and a preparation method and a use of the maleamic acid monomer. The structural formula of the monomer is as follows: formula (1), wherein, R is selected from The maleamic acid monomer provided in the present invention may be used as a comonomer to prepare temperature-tolerant and calcium salt-tolerant polymers.

Abstract: A composition and use thereof are disclosed herein. The composition comprises at least two selected from the group of amphiphilic block copolymer, polyurethane and acidic ionic compound. Also an oil-based drilling fluid comprising the composition and a method improving shearing force of oil-based drilling fluid are disclosed. The composition disclosed herewith can raise the shearing force of oil-based drilling fluid.

Abstract: A resistivity measurement while drilling (MWD) device, including: a transmitting module arranged on an outer surface of a drill collar, for generating an induced current between the drill collar and surrounding formation by inductive coupling; a receiving electrode group including at least two electrodes, for receiving a measured current that reaches the electrode from the induced current through corresponding formation, two electrodes in the receiving electrode group being multiplexing electrodes; a resistivity calculation module configured to be connected to all or a part of the electrodes in the receiving electrode group in a measurement mode of the resistivity MWD device, to calculate the measured current received by a corresponding electrode and obtain resistivity of formation corresponding to the corresponding electrode; and a data transmission module configured to be connected to the multiplexing electrodes in a transmission mode of the resistivity MWD device, for transmitting calculated resistivity to

Abstract: Disclosed is a data transmission system and a method for transmission of downhole measurement data to the ground. The system includes a drill string mounted with a logging while drilling measurement tool, and a throw while drilling section, which accommodates a micromemory. The throw while drilling section includes a housing which is mounted outside of the drill string as a sleeve to form a clearance space therebetween; a control circuit; and a wireless transceiver. The throw while drilling section releases, under function of a micromemory release instruction transmitted by the control circuit, the micromemory loaded with the downhole measurement data to the ground.

Abstract: A composition and use thereof are disclosed herein. The composition comprises at least two selected from the group of amphiphilic block copolymer, polyurethane and acidic ionic compound. Also an oil-based drilling fluid comprising the composition and a method improving shearing force of oil-based drilling fluid are disclosed. The composition disclosed herewith can raise the shearing force of oil-based drilling fluid.

Abstract: Disclosed is a data transmission system and a method for transmission of downhole measurement data to the ground. The system includes a drill string mounted with a logging while drilling measurement tool, and a throw while drilling section, which accommodates a micromemory. The throw while drilling section includes a housing which is mounted outside of the drill string as a sleeve to form a clearance space therebetween; a control circuit; and a wireless transceiver. The throw while drilling section releases, under function of a micromemory release instruction transmitted by the control circuit, the micromemory loaded with the downhole measurement data to the ground.

Abstract: The present invention provides a filtration control agent and a drilling fluid containing the same. The filtration control agent comprises the product obtained from the reaction of water, lignite, aldehyde and sulfonate polymer at 180-220° C. and the units containing sulfonate groups in the molecular chains of sulfonate polymer are at least 30 wt %. The filtration control agent provided by the present invention features a good filtration loss reduction effect and a low viscosity effect and can improve the rheological behavior of the drilling fluid, thereby meeting the requirements of the drilling of deep wells, ultra-deep wells and ultra high pressure formations.

Abstract: The present invention provides a modified starch, preparation method and use of the same, also provides a drilling fluid comprising the modified starch which contains bi-substituted starch structural units and tri-substituted starch structural units, wherein, the tri-substituted starch structural units are represented by the following formula (1), the bi-substituted starch structural units are the structural units represented by the following formula (2) and/or the structural units represented by the following formula (3), and the total content of the bi-substituted starch structural units and tri-substituted starch structural units accounts for 20 wt % or more of the modified starch, preferably 20-30 wt %, the weight-average molecular weight of the etherified starch is 50,000-600,000, preferably 80,000-580,000, wherein, R1, R2, and R3 are C1-C5 alkylene respectively, and M1, M2, and M3 are H, alkali metal element, or alkaline earth metal element respectively.

Abstract: A copolymer and preparation method and application thereof are disclosed. The copolymer is random copolymer obtained from monomers consisting of acrylamide, acrylic acid, alkenyl sulfonate, 2-acrylamido-dodecyl sulfonate, p-styrene sulfonate or isoprene sulfonate and so on. The copolymer of present invention can be used as fluid loss additive and has good fluid loss properties, which would not make the drilling fluid thicken at high temperature of 200° C. and high salt conditions of saturated brine. It has a medium-pressure fluid loss after aging and rolling for 16 h at high temperature of 200° C., as measured in accordance with the American Petroleum Institute Standard Test at room temperature, and has good properties of high temperature-resisting and salt-resisting.

Abstract: The present invention provides a dispersant and a drilling fluid containing the dispersant. The dispersant comprises the product obtained from the reaction of water, lignin, phenol, sulfonating agent, telogen and catalyst at 140-220° C., preferably at 160-180° C.; the catalyst is one or more selected from the group consisting of sulfamic acid, p-toluenesulfonic acid and benzenesulfonic acid. The dispersant provided by the present invention not only can significantly lower the viscosity of the drilling fluid but also plays a role in reducing filtration loss.

Abstract: The present invention provides a filtration control agent and a drilling fluid containing the same. The filtration control agent comprises the product obtained from the reaction of water, lignite, aldehyde and sulfonate polymer at 180-220° C. and the units containing sulfonate groups in the molecular chains of sulfonate polymer are at least 30 wt %. The filtration control agent provided by the present invention features a good filtration loss reduction effect and a low viscosity effect and can improve the rheological behavior of the drilling fluid, thereby meeting the requirements of the drilling of deep wells, ultra-deep wells and ultra high pressure formations.

Abstract: A copolymer and preparation method and application thereof are disclosed. The copolymer is random copolymer obtained from monomers consisting of acrylamide, acrylic acid, alkenyl sulfonate, 2-acrylamido-dodecyl sulfonate, p-styrene sulfonate or isoprene sulfonate and so on. The copolymer of present invention can be used as fluid loss additive and has good fluid loss properties, which would not make the drilling fluid thicken at high temperature of 200° C. and high salt conditions of saturated brine. It has a medium-pressure fluid loss after aging and rolling for 16 h at high temperature of 200° C., as measured in accordance with the American Petroleum Institute Standard Test at room temperature, and has good properties of high temperature-resisting and salt-resisting.