31results about How to "Improve single well production" patented technology

The invention discloses a pulse sand fracturing method realizing high fracture conductivity of cracks and belongs to the field of oilfield development. The pulse sand fracturing method includes steps of firstly, fracturing an ultralow-permeability reservoir horizontal well sectionally in multiple clusters, and judging whether high fracture conductivity of the cracks is formed or not by pulse sand fracturing by researching characteristics of the ultralow-permeability reservoir, if yes, executing a second step; secondly, solidifying sand by fiber fracturing fluid by pulse sand adding process in the fracturing process, and forming 'cylinder' support in an artificial crack, so that a channel network high in flow conductivity is formed in the artificial crack, and the artificial crack has high flow conductivity. By the pulse sand fracturing method realizing high fracture conductivity of the cracks, conductivity of the cracks can be improved, and single-well yield is greatly increased. The method has remarkable effect on the site, and by the method, via practical comparison, single-well yield is increased by 20% as compared with that of conventional fracturing optimized design of horizontal wells in the same area and is five to seven times of adjacent straight wells.

The invention belongs to the technical field of unconventional oil and gas output increasing transformation, and particularly relates to a re-fracturing process design method for improving the shale seamed web complexity. The method includes the steps that re-fracturing well sections are selected according to basic data of all the well sections as well as gas-bearing data and primary fracturing output increasing transformation volume ratio data; as for the candidate well sections, a stress balancing equation of discrete fractures is established, normal stresses of a fracture unit are calculated, and steering pressure of new fractured shale stratum fractures is obtained; the strength and dosage of a temporary plugging agent are determined according to the fracture height, particle sedimentation rate, fracture width and temporary plugging agent particle density as well as the number of primary fracturing seamed webs; and steering extension construction displacement of the re-fractured seams is calculated and designed. The re-fracturing process design method provided by the invention covers the basic procedures of shale re-fracturing design, the shale re-fracturing process design canbe achieved conveniently, rapidly and effectively, and a technical design method is provided for re-fracturing process mine field implementation.

The invention discloses a well completion technique for efficiently controlling pressure and retaining water cone of a horizontal well, comprising a method for efficiently controlling the pressure andretaining the water cone of the horizontal well, a device and matching technology and a theory. The method comprises the following steps: A, placing non-coupling oil tube with the function of controlling pressure and retaining bottom water coning at the middle position in the horizontal well channel; and B, setting an excluder in the horizontal well to exclude the annular space between the non-coupling oil tube and a barefoot well or to exclude the annular space between the non-coupling oil tube and a sieve tube, so that crude oil after emerging from stratum flows from two ends to the middleand only can be output by the non-coupling oil tube. The technique for efficiently controlling the pressure and retaining the water cone of the horizontal well not only can retain bottom water coning,but also can significantly improve individual-well producing rate, has simple completion technology, cheap and easily obtained raw materials, no environmental pollution, convenient oil field implementation, and low cost.

The invention relates to a well cementation casing or tubing sliding sleeve without limit on the number of segments or clusters, comprising an upper joint, a variable-diameter cylinder, a sliding sleeve body, and a lower joint. The upper joint is connected with the variable-diameter cylinder, the variable-diameter cylinder is connected with the sliding sleeve body, and the sliding sleeve body is connected with the lower joint. Grooves are arranged on the inner wall of the variable-diameter cylinder to make a variable-diameter area formed on the inner wall of the variable-diameter cylinder, and an elastic cylinder is installed in the variable-diameter area. Multiple fracturing ports are uniformly distributed in the middle of the sliding sleeve body along the circumference. The inner wall of the sliding sleeve body has a diameter expanding area which is disposed below the fracturing ports. An inner sliding sleeve is arranged inside the sliding sleeve body. The lower end inside the sliding sleeve body is equipped with a C ring. With the sliding sleeve, vertical and horizontal wells in oil and gas fields can be fractured in a layered manner under the conditions of an unlimited number of segments and an unlimited number of clusters between segments. Before fracturing, a wellbore is full-pass, and the sliding sleeve and a ball seat are non-throttled. The construction capacity is larger, the fracturing effect can be significantly improved, and the production capacity of a single well can be increased. After fracturing, a ball made of soluble material and the C ring are dissolved or drilled and ground, and the well bore is full-pass again, thus facilitating later production and operation.

The invention discloses a synchronal rotary oil-gas multiphase pump. A front end bearing seat, a rear end bearing seat, an oil cylinder, a rotor, a sliding plate, a left end cover, a right end cover, an eccentric shaft and an adjusting part are arranged inside a shell body. The adjusting part comprises a key, an adjusting nut, rear end adjustment, a rear end adjustment nut, a front end adjustment nut and a double-half-clamping structure. According to the synchronal rotary oil-gas multiphase pump, single pipeline mixed conveying, pressurization and long-distance multistage conveying of crude oil, natural gas, water and various thick materials can be achieved. An oil-gas-water separation link and an adding link in an intermediate conveying process are cancelled. Sleeve gas is recycled, and air is emptied. The well mouth return pressure is lowered, and the single well yield is improved. The synchronal rotary oil-gas multiphase pump can also be used in other industries which need long-distance pressurization conveying.

The invention belongs to the technical field of reservoir stratum protection in petroleum and gas, and geologic prospecting well drilling, and particularly relates to a method for regulating well drilling liquid granularity distribution. The method for regulating the well drilling liquid granularity distribution includes: analyzing granularity distribution curves of well drilling liquid and blocking and shielding agents according to the maximum pore throat diameter D90 of a target reservoir stratum, and screening out particle diameter proportions of the well drilling liquid and the blocking and shielding agents. The method for regulating the well drilling liquid granularity distribution has the advantages of enabling filling of the well drilling liquid to conform to an ideal filling rule by analyzing well drilling liquid granularity on the scene and supplementing the blocking and shielding agents different in grain diameter proportion, and achieving the effects of reducing filtration loss of the well drilling liquid and reducing invasion of filter liquid. According to the method for regulating the well drilling liquid granularity distribution, a curve of a relationship between accumulative volumes (%) and grain diameter square roots is drawn by considering data of the well drilling liquid granularity distribution, and then a result finally obtained is true and reliable, conforms to actual situations on the scene, and therefore the reservoir stratum can be protected well, and an output of a single well is improved.

The invention discloses a well group well spacing method of a microbial oil displacement oil recovery technology. A set of combined injection-production well pattern of horizontal well exploitation and vertical well injection is deployed in a thicker sandstone oil reservoir by utilizing a microbial tertiary oil recovery technology, and the combined injection-production well pattern needs to meet the requirements of plane correspondence, longitudinal three-dimension and bottom injection and top production; the vertical well injection refers to injecting microorganisms into a bottom area of a sandstone reservoir by using a vertical well, and the horizontal well exploitation refers to deploying the horizontal section of a production well in a top area of a thicker sandstone reservoir; the plane correspondence refers to overlapping the horizontal section of the injection vertical well and the horizontal section of the production well after being projected to the plane in an overlooking state, and an up-and-down corresponding relation is achieved; and the longitudinal three-dimensional refers to that the injection section of the vertical well and the horizontal section of the productionwell are arranged in parallel at different depths in the sandstone reservoir, and a three-dimensional well pattern is formed in the section parallel to the gravity direction and perpendicular to a main shaft of the horizontal section of the production well. The well group well spacing method has the advantages of being higher in oil sweeping efficiency, high in oil extraction capacity, higher infinal recovery ratio and the like.

The invention provides a description method of the crack fracture scale based on seismic wave full-waveform characteristics. The description method of the crack fracture scale comprises the followingsteps: generating a composite seismic source time function through modeling of the crack fracture scale, obtaining a Green function from a seismic source to an observation station through logging and/or three-dimensional seismic data, obtaining a synthetic micro seismic wave according to the composite seismic source time function, the Green function and a seismic moment tensor, and obtaining a composite micro seismic wave; calculating correlation coefficients of the synthetic microseismic waves and the microseismic waves recorded by the observation station based on the full waveform characteristics of the seismic waves, and selecting the fracture fracture scale recorded by the synthetic microseismic waves with the correlation coefficients within a preset coefficient allowable range as thefracture scale. The invention has the beneficial effects that the problem that the fracture dimension of the crack cannot be quantitatively described in passive earthquake monitoring can be solved.

The invention belongs to the technical field of oil and gas field exploration and development, and particularly relates to a system and method for realizing staged multi-cluster fracturing and multi-crack balanced expansion of a horizontal well. The system for realizing staged multi-cluster fracturing and multi-crack balanced expansion of the horizontal well is composed of a horizontal well shaftcasing pipe, a bridge plug, intelligent casing pipe sliding sleeves and a ground controller, the bridge plug is arranged at the position, at the joint of the adjacent fracturing sections of the horizontal well, on the shaft casing pipe, the multiple intelligent casing pipe sliding sleeves are arranged, different clusters of the different fracturing sections of the horizontal well shaft casing pipeare each provided with one intelligent casing pipe sliding sleeve, and the ground controller is arranged on the ground and is in electric signal connection with the multiple intelligent casing pipe sliding sleeves. According to the system and method, the problems that multiple clusters cannot fracture completely and multiple cracks cannot be expanded and extended in a balanced manner in horizontal well staged multi-cluster fracturing are effectively solved, the multi-cluster fracturing effectiveness is improved to 100%, the multi-crack balanced expansion rate is improved to 90% or above, thecontrol degree of artificial cracks on a reservoir is remarkably improved, and finally the single-well yield of the low-permeability-dense oil and gas reservoir is greatly improved.

The invention discloses an ultra-carbon connecting tube jet drilling horizontal well system and a jet drilling method. The ultra-carbon connecting tube jet drilling horizontal well system comprises an ultra-carbon closed separation circulation unit and an ultra-carbon connecting tube jet drilling unit. Waste generated in the jet drilling process is jetted, guided and recovered by the aid of supercritical carbon dioxide, so that supercritical carbon dioxide is separated, serves as drilling fluid and is circulated into the ultra-carbon connecting tube jet drilling unit again, and jet drilling is performed. The system solves the problems of small borehole diameter, complicated horizontal section and borehole problems, more waste and large pollution of a current coiled tubing jet drilling radial horizontal well taking clear water, water base, oil base, foam and the like as the drilling fluid, the diameter of a well hole and the length of the horizontal well section can be greatly increased, drilling speed, oil-gas yield and environmental protection level are improved, and well site facilities and drilling and production costs are reduced.

The invention provides a full-bore well completion fracturing method for a low-permeability reservoir sidetracking well. The method comprises the following steps: step 001, determining a target well,and opening a window in the target well to sidetrack a new borehole; step 002, assembling a well completion pipe string; step 003, lowering the well completion pipe string into the target well, and conducting setting; step 004, carrying out well cementation operation on the new borehole; step 005, pulling out the upper half portion of the well completion pipe string to be replaced with a fracturing tie-back pipe string; step 006, implementing perforating fracturing on the reservoir where the new borehole is located by a perforating gun; and step 007, pulling out the fracturing tie-back pipe string, and putting down a production pipe string to be put into production. According to the method provided by the invention, a brand-new wellbore can be built in the sidetracked slim hole of the low-permeability oil field, reservoir staged fracturing transformation or later repeated fracturing operation can be smoothly carried out, an old casing in an old wellbore is protected in the fracturing process, and the purposes of reducing the construction cost and increasing the final recovery ratio of an oil reservoir are achieved.

Disclosed is a separate-layer sand blocking simultaneous production pipe string. In order to overcome the shortcoming that due to phenomena of sand jamming, sand blocking and sand burying of an existing oil well with the serious interlayer interference, oil production cannot be smoothly carried out, an upper packer, a safety joint I, a screen pipe I, a safety joint II, a lower packer, a safety joint III, a screen pipe II and a screwed plug of the separate-layer pipe string are sequentially and fixedly connected from top to bottom through oil pipes, and an upper sealing working cylinder is fixedly arranged between the screen pipe I and the safety joint II of the separate-layer pipe string. A lower sealing working cylinder is fixedly arranged between the safety joint III and the screen pipe II, and the inner diameter of the upper sealing working cylinder and the inner diameter of the lower sealing working cylinder are smaller than the inner diameter of the oil pipes. A hollow sealing pipe is fixedly arranged at the lower end of a separate-layer oil production pump of a lifting pipe string, and the lower end of the hollow sealing pipe is always matched with an inner hole of the upper sealing working cylinder. An annulus is formed between the hollow sealing pipe and an inner hole, above the upper sealing working cylinder, of the separate-layer pipe string. The separate-layer sand blocking simultaneous production pipe string has the beneficial effects of being reasonable in structural design, and capable of avoiding the interlayer interference, and effectively improving per-well production and production aging of a sandy well.

The invention provides a T-shaped well group and a method for exploiting non-diagenetic natural gas hydrates. The T-shaped well group comprises a vertical well and a horizontal well located on one side of the vertical well, and the vertical well and the horizontal well share the same wellhead; a vertical well target point is located in a stable formation under a reservoir; a deflecting section, adeflection increasing section, a deflection stabilizing section and a horizontal section of the horizontal well are all located in a stable formation over the reservoir, and a horizontal well target point is located in the reservoir or the stable formation over the reservoir; both the vertical well and the horizontal well are provided with fracturing sand prevention layers, and a vertical well fracturing seam is a horizontal seam; and horizontal well fracturing seams are vertical seams, the lower ends of the horizontal well fracturing seams extend into the reservoir, and the number of the horizontal well fracturing seams is not less than two sections. The T-shaped well group and the method for exploiting the non-diagenetic natural gas hydrates have the beneficial effects that the verticalwell target point, and the deflecting section, the deflection increasing section, the deflection stabilizing section and the horizontal section of the horizontal well in the T-shaped well group are all arranged in the underlying stable formation or the overlying stable formation of the reservoir so that not only can the stability of wellbores of the whole well group and well control safety be improved, but also the contact area between the wellbores and the reservoir can be increased.

The invention belongs to the technical field of oilfield development downhole operation fracturing, and particularly provides a fracturing method for opening a new crack through crack saturated filling sand. A proppant is continuously injected into a primary artificial crack according to a sand-liquid ratio of 20%, 30% and 40%, and a gel breaker is added in a process of adding the proppant, so that the saturated filling sand inside the primary artificial crack is enabled to cause sand plugging in the crack; meanwhile, the net pressure in the crack is further improved by improving the construction displacement, a lateral new crack is opened, effective support is formed for the new crack, the purposes of forming a complex crack system, expanding the using degree of lateral remaining oil and improving the single well yield and the final recovery efficiency of an oil well are achieved. The technological process is simple and easy to implement, the cost is lower, and the characteristics of high on-site temporary plugging and rising amplitude controllability can greatly improve the production benefit of an oil field, and has wide application prospects in the aspects of increasing the single-well yield of lateral low-yield oil wells of ultra-low permeability reservoirs and ultra-low permeability reservoirs and improving the water drive effect of the low permeability reservoirs.

The invention relates to the technical field of later-stage exploitation of oil and gas fields, and discloses a radial well volume fracturing method. The method comprises the following steps of 100, selecting a target layer of a well to be subjected to radial fracturing, and determining the horizontal maximum principal stress direction and the horizontal minimum principal stress direction of the target layer; 200, determining the fracturing displacement and the fracturing crack length; 300, determining the number of radial water jet holes according to the fracturing displacement and the fracturing crack length in the step 200; 400, performing directional windowing and radial water jet in the direction forming a certain angle with the horizontal minimum principal stress direction, and executing the jet process till all the radial water jet holes are completed; and 500, after the jet process is completed, executing the fracturing process until all fracturing strips are completed. By means of radial water jet in the vertical well, volume fracturing is achieved in the reservoir section, the purpose of similar horizontal well fracturing is achieved, the fracture swept area is enlarged, oil and gas reserves are effectively used, and compared with conventional one-time fracturing, the single-well yield of a low-permeability oil and gas well can be greatly increased.