62 results about "Multiple fracture" patented technology

The invention relates to the technical field of oil fracturing, in particular to a method for calculating the staged fracturing productivity of a compact reservoir horizontal well. The method is characterized by including the steps of firstly, dividing a reservoir infiltration area into four parts; secondly, obtaining the equivalent hole diameter of each fracture; thirdly, obtaining the yield of each fracture during multiple fracture disturbance; fourthly, coupling the yield of each fracture with the hydraulic pressure drop flow model in a horizontal wellbore to obtain a group of bottom hole pressure, iteratively solving until the bottom hole pressure difference of the previous step and the next step is smaller than tolerance, namely convergence, and taking the determined group of yield as the fracture-control yield of each fracture and the sum of the fracture-control yield of the fractures as the total yield of the horizontal well. The method is real and reliable in calculation result and good in application effect.

The invention discloses a horizontal well staged fracturing oil production method through injection and production in the same well. Multiple fracturing cracks perpendicular to a horizontal well shaft are generated at different parts of an oil layer through the horizontal well staged fracturing; one of the cracks is selected as a fluid injecting channel, and the adjacent cracks at two sides serve as crude oil production channels; displacement crude oil flows to the cracks at two sides along the crack in the middle; a double-oil-pipe segmented sealing technology is combined to seal the crack and the adjacent two cracks; a fluid is injected in from the middle crack; the displacement crude oil flows to the horizontal well shaft from the adjacent cracks at two sides; and produced liquid flows outside the shaft along another oil pipe channel to form a segmented same-well injection and production system in the same horizontal well.

The stimulated rock volume (SRV) of a subterranean formation may be increased by pumping viscous fracturing fluid into the formation in a first stage to create or enlarge a primary fracture, decreasing the pumping in order for the fluid to increase in viscosity within the primary fracture, and then continuing to pump viscous fluid into the formation in a second stage. The fluid pumped into the second stage is diverted away from the primary fracture and a secondary fracture is created. The directional orientation of the secondary fracture is distinct from the directional orientation of the primary fracture. The fluid of the first stage may contain a viscosifying polymer or viscoelastic surfactant or may be slickwater.

The invention provides a fiber-toughened ceramic-based composite material with a ternary-layer-shaped MAX phase interface layer. A ternary-layer-shaped MAX phase material is introduced to serve as an interface layer, and therefore the anti-irradiation property, the heat-conducting property and the anti-oxidation property of the ceramic-based composite material can be effectively improved; in addition, through multiple fracture energy absorbing mechanisms of the MAX phase material, fracture energy can be effectively absorbed, extension of cracks in the ceramic-based composite material is hindered, and therefore the toughness and the damage tolerance of the ceramic-based composite material are improved. Accordingly, the application fields of the composite material are effectively widened, and the composite material has good application prospects in the fields of aerospace thermal structure materials, nuclear energy structural materials and the like.

The invention is a method and apparatus for initiating multiple azimuth controlled vertical hydraulic fractures in unconsolidated and weakly cemented sediments from a single bore hole to control the fracture initiation and propagation of hydraulic fractures at differing azimuths. The multiple azimuth vertical fractures enable greater yield and increased recovery of petroleum fluids from the formation. An injection casing with multiple fracture initiation sections is inserted and grouted into a bore hole. A fracture fluid carrying a proppant is injected into the injection casing and opens fracture initiation sections to dilate the formation in a direction orthogonal to the first fracture azimuth plane. Following completion of the first fracture injection, the fracture fluid is injected into the injection casing and opens a set of second and subsequent fracture initiation sections dilating the formation and initiating and propagating a second and subsequent vertical hydraulic fractures at different azimuths to the first and subsequent earlier installed fractures. The injection casing initiation sections remains open after fracturing providing direct hydraulic connection between the production well bore, the permeable proppant filled fractures and the formation.

A method of creating multiple fractures in a well traversing a formation is described using pressurized fluids in a highly deviated or horizontal section of the well at a pressure above the fracturing pressure of the formation, wherein for creating a fracture the pressurized fluid is alternated between an acid fracturing fluid and a proppant loaded fluid, such that the proppant blocks the flow of pressurized fluid into a fracture created during a previous step of the method and the subsequently pressurized acid fracturing fluid creates a new fracture at a location along the highly deviated or horizontal section different from the location of the previously created fracture.

A method and apparatus for initiating and propagating a vertical hydraulic fracture in unconsolidated and weakly cemented sediments from a single bore hole to control the fracture initiation plane and propagation of the hydraulic fracture, enabling greater yield and recovery of petroleum fluids from the formation. An injection casing with multiple fracture initiation sections is inserted and grouted into a bore hole. A foam fracture fluid carrying a proppant is injected into the injection casing and opens the fracture initiation sections to dilate the formation in a direction orthogonal to the required fracture azimuth plane. Propagation of the fracture is controlled by limiting the fracture fluid form to that of a stable foam fracturing fluid during the fracturing process. The injection casing initiation section remains open after fracturing providing direct hydraulic connection between the production well bore, the permeable proppant filled fracture and the formation.

The invention provides a method for forming multiple fractures by forced planar diverting of a fracture opening being temporarily plugged. The method includes: allowing temporary plugging diverting material fluid to a position near the fracture opening in a reservoir so as to form a bridge plug and force the fracture to divert, forming multiple fractures, activating micro-fractures of the reservoir with active liquid or acid liquid, and forming a multi-fracture mesh. The method according to the technical scheme has the advantages that artificial fractures in unconventional oil-gas reservoirs, such as low-permeability and ultralow-permeability oil-gas reservoirs, tight oil reservoirs and shale oil-gas reservoirs, are forced to divert in the plane, forming multiple artificial fractures having guiding ability, chances to connect reservoir bodies are increased, drainage area is enlarged, cleaning diverting material is of degradability and can fully degrade after construction, all the fractures can be utilized, and yield increase is more obvious.

A method and apparatus for initiating and propagating a vertical hydraulic fracture in unconsolidated and weakly cemented sediments from a single bore hole to control the fracture initiation plane and propagation of the hydraulic fracture, enabling greater yield and recovery of petroleum fluids from the formation. An injection casing with multiple fracture initiation sections is inserted and grouted into a bore hole. A fracture fluid carrying a proppant is injected into the injection casing and opens the fracture initiation sections to dilate the formation in a direction orthogonal to the required fracture azimuth plane. Propagation of the fracture is controlled by supplying fracture fluid independent to the two opposing wings of the hydraulic fracture. The injection casing initiation section remains open after fracturing providing direct hydraulic connection between the production well bore, the permeable proppant filled fracture and the formation.

The invention provides a method for mining shale oil by virtue of a horizontal well through performing volume fracturing on reservoirs. The method comprises steps as follows: Step 1, the fractal dimension D and the tortuous fractal dimension delta of a fracture network after volume fracturing of a reservoir are obtained through a box testing method; Step 2, a horizontal well in a test area is perforated and fractured, perforations and fractures which are perpendicular to a shaft are produced for the horizontal well, and shale oil mining is performed on the test area; Step 3, the yield of the test area under the combined action of multiple fractures of the fractured horizontal well in the test area is determined; Step 4, the effective permeability kn of the fractures and the equivalent permeability ke of matrix-fractures are determined. The method is simple and reliable in application process, the capacity of volume-fractured horizontal wells under different reservoir conditions can be predicted, only measuring parameters are required to be adjusted, the use reliability of the method is high, and the effect is good.

The invention provides a multi-layer ultrasonic transducer and a manufacturing method thereof. The multi-layer lamination ultrasonic transducer comprises a piezoelectric wafer assembly, and the piezoelectric wafer assembly comprises multiple piezoelectric wafers which are mutually bonded; the surface of each piezoelectric wafer is provided with multiple fractures, and the fractures divide an electrode layer of the corresponding piezoelectric wafer into multiple electrodes; the polarity of the electrodes of the bonding faces of the piezoelectric wafers which are mutually bonded is same; one side of the piezoelectric wafer assembly is bonded with at least one acoustic matching layer, the other side of the piezoelectric wafer assembly is bonded with at least one backing layer, the acoustic matching layer closest to the piezoelectric wafer assembly comprises a conducting area, or the backing layer closest to the piezoelectric wafer assembly comprises a conducting area. According to the multi-layer lamination ultrasonic transducer and the manufacturing method thereof, impedance of the piezoelectric wafers can be effectively reduced, and the problem of piezoelectric wafer vibration inhibiting caused by introduction of an additional coupling layer or a flexible circuit board can be solved.

The invention relates to a multistage fracturing horizontal well inter-crack interval CO2 flooding oil extraction method. The method includes following steps: performing sectional fracturing on a horizontal well shaft to form multiple fracturing cracks perpendicular to the horizontal well shaft; mounting an oil pipe I and an oil pipe II in a casing in the horizontal well shaft, mounting flow controllers I at positions, corresponding to even-level cracks, of the oil pipe I, mounting flow controllers II at positions, corresponding to odd-level cracks, of the oil pipe II, and arranging a packer at a position, between the odd-level cracks and the even-level cracks, in an annular space of an oil jacket; at an initial production stage, utilizing natural energy for extraction until bottom hole pressure is lowered to bubble point pressure, and utilizing crack intervals for extraction, injecting CO2 into the oil pipe I, wherein CO2 enters the even-level cracks, and crude oil is output from the odd-level cracks and enters the oil pipe II at the same time; when oil yield is lower than economic limit yield, stopping injecting CO2. By the method, crude oil recovery rate can be increased substantially, and gas channeling can be inhibited effectively.

The invention discloses a simulation experiment device for airborne dust transportation and control of tunneling roadways. The simulation experiment device comprises a closed simulation testing table, wherein a main simulation roadway and a side simulation roadway are arranged in the closed simulation testing table, the main simulation roadway is arranged in the length direction of the closed simulation testing table, and the side simulation roadway and the main simulation roadway form an angle of 25-35 degrees. The closed simulation testing table on one side of the main simulation roadway is provided with a drainage channel for draining accumulated water. A dust raising device for simulating dust production of the tunneling roadways is arranged at one end of the closed simulation testing table, an air inlet mechanism is arranged at the inlet position of the side simulation roadway, an air outlet mechanism is arranged at the outlet position of the main simulation roadway, multiple fracture surfaces are arranged in the main simulation roadway, and multiple air speed sensors and multiple dust sensors are evenly distributed on each fracture surface. The simulation experiment device for airborne dust transportation and control of the tunneling roadways are used for determining optimum ventilation and dust removal parameters of field operation and improves the dust control efficiency of a tunneling field.

The invention relates to a high voltage direct current breaker with multiple fractures and a tandem type. The breaker comprises a multi-fracture breaker, an oscillation loop and a dissipative element. The multi-fracture breaker includes a plurality of single-phase breakers and fractures of all the single-phase breaker are in series connection through connection buses; the multi-fracture breaker is respectively in parallel connection with the oscillation loop and the dissipative element through the connection buses; and a fracture of each the single-phase breaker is respectively in parallel connection with an RC equalizer circuit. According to the invention, fractures of a plurality of single-phase breakers are in series connection so as to form a multi-fracture tandem structure; effects of high drop-out voltage, heavy drop-put current and short drop-out time and the like are realized; and demands of ultra-high voltage and extra-high voltage direct current power transmission projects can be completely met. In addition, the oscillation loop in the invention is used for generating oscillation currents; the dissipative element is used for absorbing line energy and restricting overvoltages after currents are switched off; and the RC damping circuit is used for improving equalizing voltages between fractures of all the single-phase breakers.

The invention provides a method for controlling fracturing of multiple fractures of an oil and gas field with a natural micro-fracture-developed reservoir stratum. By adopting the early high-sand-ratio powdery ceramsite proppant slug technique, a few ceramsites are injected by a high-sand-ratio proppant slug at a prepad fluid stage to plug natural fractures of the reservoir stratum, and therefore, the generation of the multiple fractures is effectively controlled and reduced, and the construction success rate and the post-fracturing effective rate are improved. With the high-sand-ratio proppant slug entering the stratum, all cracks of which the crack width is smaller are plugged. New multiple fractures during the extension process of a major fracture are plugged by a low-sand-ratio proppant slug at middle and later periods. After the high-sand-ratio proppant slug is added, as proved by fitting construction net pressure, the natural micro-fractures are largely plugged, and the pressure of the reservoir stratum slightly rises. As the multiple fractures are effectively controlled, the construction pressure is stable, and the goal that the multiple fractures are controlled to form the major fracture is achieved. Proved by a test in Yao Ying Tai oil field of Jilin province, the fracturing method for controlling multiple fractures of the oil and gas field with the natural micro-fracture-developed reservoir stratum has the advantages that the implementation is simple, the application is convenient, and the multiple fractures are effectively controlled, and is suitable for being applied to the reform of the natural micro-fracture-developed reservoir stratum.

The invention provides a core porosity measurement method and a core porosity measurement device. The core porosity measurement method provided by the invention comprises the following steps: after the outer surface of a rock sample is covered with a gel coat, placing the rock sample covered with the gel coat into first liquid, and obtaining the volume of the rock sample; measuring the pore volume of the rock sample; and obtaining the porosity of the rock sample according to the volume of the rock sample and the particle volume of the rock sample. The core porosity measurement method can accurately measure the core porosity of the rock sample when multiple fractures are formed in the surface of the rock sample and the heterogeneity is relatively high.

Disclosed herein is a fracturing unit for hydraulic fracturing having an engine and a fracturing pump connected to the engine through a variable speed torque converter. Also disclosed is a hydraulic fracturing system using multiple fracturing units which are sized similar to ISO containers. A hydraulic fracturing system may also force flow back water, produced water, or fresh water through a heat exchanger so that heat from the fracturing engines can be transferred to these liquids in order to vaporize them. A force cooled fractioning unit then can accept the vapor/steam in order to condense the various components and produce distilled water for re-use in the fracturing process or for release into the environment.

The invention discloses an automatic control system of a fracturing truck. The automatic control system comprises a host computer, a programmable logic controller, a data acquisition system and a control actuator. The data acquisition system includes a pressure collector and a discharge collector; the control actuator comprises a frequency converter and an actuator motor; the output of the pressure collector and the output of the discharge collector are connected with a data processing unit; the data processing unit is connected with the programmable logic controller; the output of the programmable logic controller is connected with the frequency converter; and the programmable logic controller is connected to the host computer through a line. The beneficial effects of the invention are that: the local monitoring and the remote monitoring are realized; the operator can timely and accurately monitor the real-time working condition data and adjust the running state; the operator at the remote control computer can simultaneously monitor multiple fracturing trucks; the difficulty of monitoring is reduced and the monitoring efficiency is enhanced; the parameter can be set, so that the fracturing pump can operate in the automatic and stable manner; and the advantages of the convenient control, centralized monitoring data, and far control distance are realized.

The invention discloses a researching method of alpine tunnel hazard, which comprises the following steps: adopting arch line as standard to divide the tunnel into left and right semi-arches and road to research; recording sectional position, sectional part, fracture incidence, fracture length, fracture breadth, pH value of leakage, fracture shape and leakage pattern in the tunnel; sketching the multiple fractures and complex position of fracture; using digital camera to pick up photo or video; proceeding rebound experiment when doubting the concrete strength of fracture part. The invention can do specific and overall on-site research for kinds of hazard for tunnel based on observation and simple measurement, which redisplays the three-dimensional hazard on the computer.

The invention belongs to the technical field of the oil industry, and particularly relates to a measurement device and method for fracture shapes after physical model samples are fractured. The device comprises a test rack (1), locating clamping strips (2) are installed on the test rack (1) and are provided with a linear locating guide rail (3), the linear locating guide rail (3) is connected with a locating sliding block (4), the locating sliding block (4) and a locating box (5) are fixed together, a laser distance measuring instrument is installed in the locating box (5), the locating sliding block (4) can drive the locating box (5) to transversely move on the linear locating guide rail (3), and the linear locating guide rail (3) can longitudinally move on the locating clamping strips (2). The device is easy to operate, low in cost, convenient to use and high in precision, and the measurement method for the fracture shapes after the physical model samples are fractured through the device is applicable to indoor hydraulic fracturing physical experiment simulation and can accurately recognize multiple fractures.

A cyclic steam soak (CSS) stimulation method for producing heated hydrocarbons from a viscous hydrocarbon-containing formation comprises the steps of: a) drilling a well (1) having a substantially horizontal or inclined lower section (3) into the viscous hydrocarbon-containing formation (4) substantially along the trajectory of the minimum compressive horizontal stress Sh; b) cutting at selected intervals along the length of the lower well section (3) substantially disk-shaped cavities (5A-5D) into the viscous hydrocarbon-containing formation (4) by a rotating hydraulic jet cutting device (6); c) completing the well (1); d) injecting steam into the well (1) and disk-shaped cavities (5A-5D) at such an elevated pressure that the hydraulic pressure in at least one disk-shaped cavity 5A is above the formation fracturing pressure, thereby fracturing the formation (4) and permitting the steam to invade the formation surrounding the fracture and to heat hydrocarbons in the steam invaded zone; e) interrupting steam injection and producing heated hydrocarbons via the well (1); and f) repeating steps (d) and (e) a number of times.

The invention discloses a rock-like sample manufacturing mold which comprises a bottom plate, side plates, clamping plates, transverse positioning pieces, longitudinal positioning pieces, steel sheetfixing pieces and prefabricated crack steel sheets, the side plates, the clamping plates and the bottom plate form a rock-like sample pouring space, and the transverse positioning pieces, the longitudinal positioning pieces and the steel sheet fixing pieces jointly form a crack positioning assembly for positioning of fracture locations. The mold has the characteristics of being simple in structure, convenient to operate, good in sealing performance and capable of controlling different sizes and orientations of the double fractures, can effectively solve the problem that an original rock sampleis difficult to prefabricate multiple fractures due to the limitation of a cutting technology, and is used for analogy research on a fracture mechanism, the crack size effect and the crack orientation effect of a fracture-containing solid rock material.