219 results about "Displacement pressure" patented technology

An auger bit is provided for a foundation pile system including a drilling rig adapted for mounting and rotating a grout pipe connected to the auger bit to form an auger. The auger bit includes a stem with lower and upper sections, which taper towards a transition whereat the stem has a maximum diameter. Right-hand flighting is mounted on the stem lower section and converges with left-hand flighting mounted on the stem upper section at a transition. The stem and the flighting have substantially equal diameters at the transition whereby soil is displaced laterally and compacted at the borehole perimeter during drilling of same. A pile foundation forming method includes the steps of providing a drilling rig, forming an auger with a grout pipe coupled to an auger bit, rotating the auger with the rig, forming a borehole with laterally displaced soil, pumping pressurized grout through the auger and into the borehole, placing a reinforcing cage in the wet grout and curing same.

The invention discloses an experimental test method for gas reservoir reverse imbibition water blocking damage evaluation under a high-temperature and high-pressure condition. The experimental test method is completed through a water blocking effect experimental measuring device. The experimental test method comprises the steps that firstly, a core is washed and dried to be placed into a core holding unit; secondly, the core is vacuumized, displacement pressure is increased to formation pressure Pf, and formation water is injected into the core under constant pressure; thirdly, the temperature is raised to the formation temperature T0; fourthly, nitrogen is injected into the core, displacement is carried out until the liquid level of a water measuring meter at the core outlet end does not change, and gas phase permeability K1 is calculated; fifthly, formation water is injected into the core until no gas is discharged out of the core outlet end; sixthly, secondary gas driving water is carried out on the core, displacement is carried out until the liquid level of the water measuring meter at the core outlet end does not change, and gas phase permeability K2 is calculated; seventhly, the damage degree of water blocking damage to the gas phase permeability is determined. The experimental test method conforms to the actual gas reservoir developing process, a reasonable testing method is provided for reservoir water blocking damage measuring evaluation, and the experimental test method has wide market prospects.

The invention discloses a quantitative evaluation method for lateral sealing of a fault.The method is mainly based on the research about the fault sealing mechanism and influence factors thereof, under the circumstance that pressure bearing time of the fault is considered, a fault-reservoir displacement pressure difference method for quantitative evaluation of fault sealing is improved, and a fault sealing quantitative evaluation geological and teaching model taking the time factors into consideration is established.The gradual-approximation algorithm with the given step length is adopted, it is determined that rocks of a surrounding rock stratum have the same shale content as a target spot stratum and the burial depth at the diagenetic degree, then according to the relation between the product of the shale content of the rocks built in a research area and the burial depth and the displacement pressure, the displacement pressure of target spot stratum rocks is calculated quantitatively and compared with the displacement pressure of a target disc reservoir stratum, and whether the fault is sealed or not as well as the magnitude of the sealing capability are evaluated quantitatively.It is verified through actual data that when compared with a fault rock shale content (SGR) method and the fault-reservoir displacement pressure difference fault sealing evaluation method which does not consider pressure bearing time, the method has feasibility.

The invention discloses a method for testing gas-water relative permeability of a dense core. The method comprises the following steps: (1) preparing an experimental core, measuring the porosity and the klinkenberg permeability of the core, and determining the minimum return pressure of weakening a slippage effect; (2) establishing water saturation in the core by utilizing formation water or simulation formation water; (3) arranging the core in a core holding unit, applying confining pressure to the original effective stress or reservoir overburden pressure and constant displacement pressure p1, applying return pressure p2 at the core outlet, and measuring the gas flow of the core; (4) measuring the gas flow of the core under different water saturations, and calculating the gas-phase effective permeability and gas-phase relative permeability of the core; (5) establishing 100 percent of water saturation in the core, and measuring the accumulated water yield of the core in unit time; and (6) calculating the water-phase effective permeability and water-phase relative permeability of the core. The method disclosed by the invention can be used for really reflecting the gas seepage conditions under in-situ conditions and simulating the underground production state and has wide market prospects.

The invention relates to a determination method of the CO2 displacement minimum miscible pressure of a low and ultra-low permeability reservoir. The method includes the steps of 1, selecting a physical model core; 2, conducting anti-corrosion treatment on the physical model core; 3, applying confining pressure to the physical model core and conducting vacuumizing; 4, measuring the pore volume of the physical model core and calculating the porosity of the physical model core; 5, heating the physical model core to a target formation temperature and measuring the permeability to water; 6, simulating the oil saturation process, recording the volume of saturated simulated oil and calculating the initial oil saturation; 7, simulating CO2 displacement, recording the displacement pressure and the outlet end liquid and gas volumes and calculating the CO2 displacement recovery rate; 8, replacing the physical model core with another physical model core with the same permeability and repeating the steps 1-7 to obtain CO2 displacement recovery rates under different displacement pressures and return pressures; 9, drawing a relation curve of the CO2 displacement recovery rates and the return pressures, wherein the return pressure corresponding to the recovery rate inflection point on the relation curve is the CO2 displacement minimum miscible pressure of the low and ultra-low permeability reservoir.

The discharge determination device which determines discharge status in a droplet discharge apparatus comprising: a nozzle which discharges a droplet of liquid; a pressure chamber which is connected to the nozzle and stores the liquid to be discharged from the nozzle; a supply flow channel which supplies the liquid to the pressure chamber and is connected to the pressure chamber; and an actuator which causes the droplet to be discharged from the nozzle by causing at least a portion of the pressure chamber to deform and thereby applies a pressure change to the liquid inside the pressure chamber, the discharge determination device comprises: a pressure determination device which is disposed inside the pressure chamber and includes a film member forming a portion of a face constituting the pressure chamber, the film member being displaceable in accordance with pressure change in the liquid inside the pressure chamber, the pressure determination device outputting a determination signal in accordance with displacement of the film member; and a discharge status judging device which judges the discharge status of the nozzle according to the determination signal obtained from the pressure determination device in accordance with driving of the actuator.

The invention provides a test system and method of fluid non-linear percolation characteristics in a low-permeability porous media. The test system comprises a plurality of test branches, wherein, each test branch comprises a displacement pressure output unit for providing different pressures to transfer displacing fluid to a test core, a pressure measuring unit for the pressure of the displacingfluid output by the displacement pressure output unit, a flowing unit for accommodating the test core and providing ring crush to the test core, a flow measuring unit for measuring the flow of the displacing fluid flowing through the test core, and a thermostatically control unit for providing a constant ambient temperature for the flowing unit and the flow measuring unit. By adopting the thermostatically control unit, the influence of variation in temperature to the test results is eliminated, so that the test results are accurate.

The invention relates to a rock core displacement effect visual evaluation method. The distribution characteristic and effect of a solution A for displacing another solution B in the rock core are determined by using specific rock core nuclear magnetic resonance equipment, wherein the solution A and the solution B need to be selected from different groups, and are significantly different in relaxation time. The method comprises the following specific steps of: placing a rock core in a rubber tube, thermosetting, placing into an anti-magnetic holder, and placing into a nuclear magnetic resonance test coil; loading the solutions A and B into a solution container; starting nuclear magnetic resonance imaging MRI and rock core application as well as displacement software, and inputting data of the rock core and a displacement solution; adjusting the flow rate and the pressure difference between annular pressure and displacement pressure, starting a pump to displace the solution A, and reversing the process to displace the solution B when only the solution A flows from the outlet; determining and recording 2D images and T2 spectra of the rock core and fluid at different moments when the solution A is displaced by the solution B, and stopping displacement when the 2D images and T2 spectra have no changes; and processing the data to obtain the distribution cloud images of the fluid at different moments.

The invention relates to the field of geothermal exploitation and provides a single-well fracture gravity self-circulation dry-hot-rock geotherm mining method. According to the method, perforation holes of different depths are utilized, the fracture size of a dry-hot-rock reservoir is increased through a water jet technology and a size fracture technology, and accordingly the upper area and the lower area of the reservoir communicate efficiently through fracture cracks; low-temperature heat-carrying fluid flows to the dry-hot-rock reservoir along the perforation holes in the upper portion after being injected in an annular mode, and then flows to the fracture cracks of the lower area under the actions of displacement pressure and gravity caused by the potential-energy difference of the fracture cracks of the upper portion and the lower portion; and finally, under the action of a ground suction pump, the heated heat-carrying fluid flows back to the ground along the perforation holes in the lower portion via a heat insulating oil pipe. According to the single-well fracture gravity self-circulation dry-hot-rock geotherm mining method, geothermal exploitation is carried out by annular cyclic injection and production of the heat-carrying fluid through the single-well oil pipe, and the expenses for drilling two injection and production wells in the conventional dry-hot-rock geotherm mining process is greatly reduced; and meanwhile, through use of the highly heat insulating oil pipe, the heat loss caused when the heat-carrying fluid is mined out of the oil pipe is reduced, and the heat collection capacity of the heat-carrying fluid is greatly improved.

The invention provides a testing apparatus used for simulating foundation pit three-dimensional seepage caused by combined effects of separating-lowering-pouring and ground deformation mechanism. The testing apparatus is used for solving a problem of lack of experiment equipment, which is used for simulating foundation pit three-dimensional seepage caused by combined effects of separating-lowering-pouring and ground deformation mechanism, and systematic researches on relating data and mechanism at present. The testing apparatus comprises a model casing, geotextile, permeable steel plates, underground diaphragm walls, a pumping well, a recharge well, measuring devices and data collecting devices. The model casing is divided into a water zone, a soil zone and a foundation pit zone; the measuring devices comprise a flowmeter, a stratum displacement meter, a water manometer, a contact electric displacement meter, a pore water pressure gauge, and the like, and is capable of realizing accurate measurement on flow displacement pressure; and the data collecting devices are connected with the measuring devices. The testing apparatus is capable of realizing researches on the mechanism of pumping depression cone and recharge lifting underground water level three-dimensional seepage effects, and the relationship between ground deformation and groundwater table fluctuation.

The invention provides a method for representing an oil-water relative permeability curve under the condition of different driving displacement pressure gradients, and belongs to the technical field of reservoir engineering in oil development. The method comprises the following steps that (1) different driving displacement pressure gradients are exerted on a group of rock cores with identical or similar permeability to obtain the relative permeability experiment data of each rock core, then, a permeability curve corresponding to each rock core is made according to the relative permeability experiment data, and next, the relative permeability curve corresponding to each rock core is subjected to normalization processing to obtain an oil-water relative permeability curve corresponding to each rock core; (2) the statistical laws on the water phase maximum relative permeability, the oil displacement efficiency and the pressure gradient are fit out according to the relative permeability experiment data, and the water phase maximum relative permeability and the residue oil saturation degree under different pressure gradients can be solved; (3) a characteristic curve equation of the relative permeability curve corresponding to each rock core is solved.

The invention provides a method for acquiring a maximum seepage flow resistance gradient of an oil-water two-phase flow of a compact low-permeability oil reservoir. The method comprises the steps of: step 1, measuring a steady-state pressure gradient-flow relationship, and drawing curves of a relationship between an oil displacement pressure gradient and a relationship between a water displacement pressure gradient and the flow separately; step 2, fitting the experimental curves to obtain respective non-linear seepage flow parameters of oil and water phases; step 3, calculating a water saturation numerical value corresponding to the maximum seepage flow resistance gradient by utilizing the obtained non-linear seepage flow parameters of the oil and water phases; step 4, and calculating a seepage flow resistance gradient of a core by using the water saturation numerical value corresponding to the maximum seepage flow resistance gradient. The method for acquiring the maximum seepage flow resistance gradient of the oil-water two-phase flow of the compact low-permeability oil reservoir can quantitatively characterize the maximum seepage flow resistance in water-flooding exploitation of the low-permeability oil reservoir, and lays a foundation for the rational and effective exploitation of the low-permeability oil reservoir.

The invention discloses an experiment system for simulating the grouting effect of an old goaf and relates to the technical field of coal mines. The experiment system comprises a main experiment bodydevice, a slurrying device, a grouting volume-grouting pressure double control servo device, a displacement-pressure double control servo device and a control center, wherein the main experiment bodydevice comprises a base, an experiment module, a grouting steel pipe, a cross beam and other parts, and a loading oil cylinder is arranged in the middle of the cross beam and connected with a loadingpress head and controls the loading press head to move vertically; the experiment module is formed by a semi-circular member I and a semi-circular member II through buckling, when moving vertically downwards, the loading press head is completely attached to the inner wall of the experiment module, and a confined space is formed between the loading press head and the experiment module. With adoption of the system, indoor analog simulation for the grouting condition of the old goaf can be performed in advance, and strength of grouting solids after the experiment is detected, so that the groutingreinforcement effect is predicted.

The invention relates to a low and ultra-low permeable reservoir CO2 drive near-miscible pressure area determining method. The method includes: 1), selecting and pre-processing a physical model core; 2), adding circling pressure and performing vacuum pumping; 3), measuring pore volume and calculating porosity; 4), heating to target strata temperature and performing water measurement on permeability; 5), simulating saturated-oil process and calculating initial oil saturation; 6), simulating CO2 displacement and calculating CO2 drive recovery rate; 7), repeating the steps 1) to 6) to acquire the CO2 drive recovery rate under different displacement pressure and back pressure conditions; 8), drawing a relation curve of the CO2 drive recovery rate and back pressure; 9), according to rate of the curve, dividing the CO2 drive into three phases of the immiscible phase, near-miscible phase and miscible phase to acquire a trend line of the relation curve of the immiscible phase, near-miscible phase and miscible phase CO2 drive recovery rate and back pressure; 10), determining the low and ultra-low permeable reservoir CO2 drive near-miscible pressure area according to the intersection of the immiscible phase and the near-miscible phase and the intersection of the near-miscible phase and the miscible phase.

The invention provides a reservoir capillary pressure curve determinator under a high temperature and a pressure. The determinator comprises a ring pressure system, an injection system, a core clamping system, a semi-permeable baffle plate, a back pressure system, a measuring system, a data automatically collecting and processing system, and a thermostat which are connected through pipelines. A semi-permeable baffle plate method is adopted to measure capillary pressure curves under a stratum condition, and the basic rationale is that a principle of balance between an impressed pressure and the capillary pressure is used to measure the capillary pressure curves under the high temperature and the pressure. Core saturated wetting phase fluid displaces a wetting phase with a nonwetting phase under a certain displacement pressure. When the impressed pressure overcomes the capillary pressure of a certain capillary in the core, the wetting phase fluid in the capillary is discharged gradually, and the wetting phase fluid saturation in the core is reduced. Pressure is increased stepwise, accumulated discharged quantity of the wetting phase fluid when the wetting phase fluid is no longer discharged and an injection pressure are measured, and the capillary pressure curves can be solved.

The invention provides a medium and high permeability oil pool ultrahigh water content later low-cost equivalent water flooding method. The medium and high permeability oil pool ultrahigh water content later low-cost equivalent water flooding method comprises the steps of: (1) evaluating the oil pool energy keeping condition; (2) evaluating the oil pool liquid production and water injection capacity and promotion potential; (3) evaluating the equivalent water flooding well distance range and the displacement pressure gradient; (4) establishing and performing the equivalent water flooding well pattern adjustment scheme; (5) evaluating the equivalent water flooding single well liquid production capacity and the production pressure difference; (6) establishing and performing the equivalent water flooding stratum pressure rising scheme; (7) establishing and performing the water channeling prevention scheme in the pressure recovery period; and (8) establishing and performing the oil well large liquid production scheme. The medium and high permeability oil pool ultrahigh water content later low-cost equivalent water flooding method exerts the stock oil water well effect to the greatest extent, can realize equivalent development effect to a dense well pattern on the basis of largely reducing the new well investment and the old well operation cost, and improves the economical benefit of old oil field development.

The invention provides an oil field fracturing transformation method. The method comprises the steps of selecting oil-driving activated water according to reservoir wettability, utilizing simulation software to work out a fracture spacing of an effective displacement pressure system and a minimum fracture spacing for avoiding stress interference, and combining and optimizing to obtain an optimal fracture spacing; carrying out conventional fracturing transformation on a first section of a horizontal well with adding a support agent, carrying out large-scale oil-driving activated water fracturing transformation on a second section of the horizontal well without adding the support agent, alternatively carrying out the two fracturing processes on follow-up well sections, and after the fracturing is finished, closing the well, and carrying out open flow production after fracture closure. According to the oil field fracturing transformation method provided by the invention, subdivision cutting fracturing transformation and fracturing fracture interval displacement are combined, and traditional interwell long distance displacement is transformed to fracture interval short distance displacement on the same well and same layer, so that the displacement pressure system is favorably built, and the oil recovery ratio can be greatly improved; the usage of the support agent and fracturing fluid gel is greatly reduced, so that the fracturing transformation cost is greatly reduced, and an important method is provided for qualitatively and beneficially developing low-osmolar and compact reserves.

The invention discloses a construction method and device for a guide displacement pressure precast pile. The construction device comprises a spiral drill power head (1), a soil outlet (2), a multi-functional pile hammer (3), a pile driver (4), a chuck (5), a long spiral drilling tool (7), a precast pile bottom (8), a drill bit (9) and a spiral piece (10), wherein the drill bit (9) is a diameter-expanded drill bit. In the construction process, the drill bit (9) can expand outwards to spirally cut off the soil on the lower portion of the precast pile; after the construction, the drill bit (9) contracts so as to draw back smoothly. Because the construction method and device are adopted for construction, construction programs are simple, and the construction can be smoothly carried out on a hard stratum with great hardness.

The invention relates to a one-well multi-control method for an offshore low-permeability reservoir single relatively thick oil layer. The method at least uses a long section horizontal well and a plurality of artificial fractures located between an oil layer top and an oil layer bottom, wherein the extension direction of a well section of the horizontal well is the maximum principal stress direction of a stratum; the artificial fracture surfaces are vertical to the horizontal well section and extend along the minor principal stress direction; injection and recovery are carried out simultaneously by implementing an offshore same-well injection and recovery technology in the horizontal well; injection water is firstly injected into the artificial fracture at the farthest end from the root of the horizontal well section; the injection water drives crude oil to enter the closest artificial fracture to enter a wellbore so as to be recovered; and when the far end artificial fractures are flooded by water in succession and water plugging is invalid, conversion is carried out in sequence from a far end to a close end. According to the method, the well building cost is reduced; the injection effect is improved; the distance between adjacent artificial fractures is adjusted, so that the small-well-distance water injection is realized, the displacement pressure gradient is favorably built, the start pressure difference is overcome, and the oil recovery effect is increased.

The invention provides a tight sandstone gas reservoir sensitivity experiment evaluation method, comprising the following steps: performing first vacuumizing treatment on a core sample, and performingfirst saturation treatment on the core sample by using simulation formation water; performing first centrifugal treatment on the core sample after first saturation treatment, until the water saturation of the core sample reaches the initial water saturation of the reservoir; testing the gas measured flow rate of the core sample after first centrifugal treatment in preset displacement pressure; performing second vacuumizing treatment on the core sample, and performing second saturation treatment on the core sample by using a to-be-evaluated fluid; performing second centrifugal treatment on thecore sample after second saturation treatment, until the water saturation of the core sample reaches the initial water saturation of the reservoir; and testing the gas measured flow rate of the coresample after second centrifugal treatment in a preset displacement pressure, so as to obtain the damage degree of the to-be-evaluated fluid to the core sample. According to the method disclosed by theinvention, the core damage can be accurately evaluated.

The invention discloses a method for assessing a classification standard of a tight reservoir pore structure based on nuclear magnetic resonance. The method comprises the following steps of 1, measuring the porosity and permeability of each rock center; 2, measuring the displacement pressure, mid-value pressure, sorting coefficient, pore throat radius and maximum mercury saturability of each rockcenter; 3, analyzing the petrologic feature of each rock center, and the pore throat combination and pore type of the rock center; 4, testing the movable fluid saturation and the movable fluid porosity parameter of each rock center; and 5, based on the abovementioned parameters, dividing the rock centers into I, II and III three types according to the good, middle and bad comprehensive assessmentof reservoirs, and building a classification assessment standard of the three kinds of reservoirs. The invention firstly provides the method for assessing the classification standard of the tight reservoir pore structure based on nuclear magnetic resonance; the reservoir types divided by the method are more accurate and scientific, and the basis is provided for subsequent exploration and development of the tight reservoirs.

The invention discloses a method for continuously detecting physical parameters of compact rocks. The method includes the steps: selecting a rock sample, drying the rock sample, measuring the size andweight of the rock sample, taking formation water, soaking a fiber with a gap, repeatedly rolling a rock core on the fiber, uniformly soaking the outer surface of the rock core except for two end surfaces, placing the rock sample into an adjusted nuclear magnetic resonance spectrometer to obtain a T2 spectral curve of the sample, taking out the rock sample to dry the rock sample, performing saturation treatment on the rock core by the formation water, and testing a T2 spectral curve by the nuclear magnetic resonance spectrometer; taking out the rock sample, placing the taken rock sample intoa rock core clamping device, applying displacement pressure until the displacement pressure reach a suitable displacement pressure difference value, accurately recording needed parameters after a system is stabilized, continuing to measure the rock sample by a soap film flow meter, measuring a T2 spectral curve of the rock sample again, and analyzing and calculating acquired data to obtain variousof needed parameters. The method has the advantages that data are accurate and reliable, time is saved, and the method is convenient and rapid.

The invention discloses a casting method of an epoxy resin covered rock core. The casting method comprises the following steps: determining a casting material type, wherein materials include an adhesive, a curing agent and a toughening agent; the adhesive is epoxy resin, the curing agent is polyamide resin and the toughening agent is dibutyl phthalate; mixing the adhesive, the curing agent and the toughening agent; uniformly and slowly injecting the mixed materials into a mold with the clamped rock core under the condition that the mold is horizontally arranged, and casting; finally, standing and cooling for 24h; detaching the mold and removing a casting finished product; and carrying out edge and corner polishing and beautifying. According to the casting method of the epoxy resin covered rock core, a manual rock core is subjected to external sealing and casting through the epoxy resin and has a good pressure bearing capability and stable rock core properties; and an application range of the rock cores is widened and displacement pressure is expanded to the use upper limit of 6MPa from the use upper limit of 1.0MPa, so that a foundation is laid for researches of indoor displacement experiments.

The invention discloses a device and a method for researching rock physical property parameter change under the action of an acid fluid. The method comprises the steps of wrapping a cylindrical test sample and a porous gasket by using a sealing material; putting into a reaction kettle; vacuumizing a system; saturating water to the system after being vacuumized; preparing the acid fluid according to demands and sampling and analyzing; keeping a system pipeline at constant temperature; exerting confining pressure and backpressure to the reaction kettle; exerting porous pressure; and measuring permeation coefficients and displacement pressure of the material in real time. The device is excellent in antiseptic property; due to a liquid preparation relay device, the difficulty of preparing a large-capacity acid fluid under high pressure condition is solved, and the contact area of the acid fluid with the device is reduced as much as possible; and a sealing structure of a rock core end part is in a mode that a bandage is adopted to be tightly tied and sealed with a side surface sealing material at a sharp ring of an end part gasket, so that the device is simple and economic, and at the same time, anti-corrosion and sealing are realized.