Method for carrying out sectional isolation of water pressing, pressure measuring and water pumping drilling
Technical Field
The invention relates to the field of geology, in particular to a method for carrying out sectional isolation of water pressing, pressure measuring and water pumping drilling.
Background
In the prior art, a stratum is revealed by utilizing drilling, and corresponding water pressure tests, fluid pressure tests, water pumping tests and the like are carried out on a stratum in a certain section so as to obtain corresponding parameters of the stratum in the test section. The strata are distributed in layers, and the permeability, pore pressure, pore fracture structure morphology and the like are different among each layer. If the corresponding parameters of the preset horizon are to be obtained accurately, the horizon must be separated from other horizons to prevent interference and influence of other horizons when corresponding tests are carried out.
At present, a conventional drilling hole is cylindrical with equal diameter, and if the sectional isolation of the drilling hole is to be realized, a current common method is to install a device with a variable volume in the drilling hole. The device is lowered to a preset position under the state of smaller volume, and then the device is enlarged by adopting a corresponding method so as to realize the sectional isolation of the drilling holes. There are three main ways currently in common use: firstly, an airbag is adopted for isolation, firstly, an uninflated airbag is lowered to a preset position, then a specially installed pipeline is adopted for inflating the airbag, after the airbag bulges, a drilling space of an isolation section is blocked, a test section and a test section between the two airbags are generally isolated through an upper airbag and a lower airbag or a front airbag and a rear airbag, recovery can be realized after the air discharging of the airbags is finished after the test and the test, a high-pressure pipeline for inflating the airbag is specially installed, the airbag is required to be lowered simultaneously with a drill rod, the space of the drilling hole is limited, the pipeline is extremely inconvenient to lower, and the pipeline is easy to tear off for a deep hole, as shown in China patent 201910821076.3; secondly, as in the chinese patent 201911174604.7, a mode of isolating different sections in a borehole is provided, in which a rope is specially installed, and the diameter of the separator is increased by the pulling action of the rope to perform the isolating function, and in this method, the rope is inconvenient to be lowered and operated, and is easy to be wound and torn during deep hole; third, the spacers are made of an expanded material, such as chinese patent 202010250896.4, which uses the expansion of a material installed in a fixed location to separate different sections of a borehole, but once the separation is formed, the separated material cannot be recovered and is difficult to clean.
Disclosure of Invention
Aiming at the technical defects, the invention aims to provide a method for carrying out sectional isolation of water pressing, pressure measuring and water pumping drilling, which is suitable for lithologic strata with high strength and stable structure, has simple principle and relatively convenient operation, and has application value for a water pressing test, a fluid pressure test and a water pumping test of any stratum layer corresponding to a test section of drilling holes with any azimuth and inclination angles.
In order to solve the technical problems, the invention adopts the following technical scheme:
the invention provides a method for carrying out water pressing, pressure measuring and water pumping drilling sectional isolation, which comprises the following steps:
1) Constructing the drilling holes corresponding to the test sections into inverted truncated cone shapes according to the position requirements of the test sections;
2) After the drilling construction is finished, reversely calculating the hole diameters of the upper end face and the lower end face of the segmented horizon according to the drilling depth of the position of the segmented horizon to be tested;
3) The upper separating device and the lower separating device which are also inverted truncated cone-shaped are selected to seal the upper end face and the lower end face of the segmented horizon respectively, the upper separating device and the lower separating device are fixedly connected through a high-strength flower pipe, the upper end of the flower pipe penetrates through the upper separating device and then is connected with a drill rod and is communicated with the space in the drill rod, the flower pipe is of a hollow structure, a part of the flower pipe, which is positioned between the upper separating device and the lower separating device, is provided with a plurality of through holes, and pressure is applied to the upper separating device through the drill rod, so that the upper separating device and the lower separating device are stably arranged on the upper end face and the lower end face of the segmented horizon, and finally the separation of a test section is realized;
4) After the sectional layer to be tested is formed, carrying out a water pressing test, a fluid pressure test and a water pumping test on the test section and the test section through the space in the drill rod;
5) After the test is completed, the drill rod is pulled out, the upper separation device and the lower separation device are pulled out to recycle the drill rod, the drill holes can be restored to the original state, and the test work of any other sectional layer can be continued according to the test requirement.
PreferablyIn the step 1), the concrete method for constructing the drilling holes corresponding to the test sections into the inverted truncated cone shape comprises the following steps: the test section is arranged at the depth H 1 To H 2 The position of the drilling hole is set as o point, and the hole depth is o to H 1 The section is constructed into a cylinder shape by adopting conventional drilling equipment, and the aperture is d 1 Access hole depth H 1 Total length H for time exchange 2 -H 1 Is consistent with the final pore-forming shape, and the outer diameter d of the bottom end of the drilling tool 2 The tip of the external channel d 1 Wherein d is 2 <d 1 The test section is constructed to have a top diameter d 1 The diameter of the bottom is d 2 Is drilled in the shape of a reverse truncated cone, and the diameter d is adopted if required 2 The other non-test sections are constructed in a conventional cylindrical shape.
Preferably, in the step 2), the method for back calculating the hole diameters of the upper end face and the lower end face of the segmented horizon is as follows: such as layered layer at hole depth H 1 ' to H 2 ', wherein H 1 <H 1 ’<H 2 ’<H 2 The drilling hole diameters of the upper end face and the lower end face of the layering layer are respectively d 1 ' and d 2 'A'; d is then 1 ' and d 2 The' calculation formula is respectively:and->
Preferably, the upper and lower spacers are made of rubber having a certain elasticity and have a height of 0.5m up and down.
Preferably, in step 3), the outer diameters of the lower ends of the upper separation devices are d respectively 1 The external diameter of the upper end of the lower separation device is d 2 ′+10mm。
Preferably, in the step 3), the pipe is replaced by a drill rod, the drill rod passes through the upper separating device and is fixed on the lower separating device, the upper separating device is also fixed with the drill rod, and a through hole for communicating the inner space of the drill rod is formed in the outer wall of the part of the drill rod between the upper separating device and the lower separating device.
Preferably, in step 4), during relevant tests and testing, the upper separation device and the lower separation device keep the descending length unchanged through the clamping and force application actions of the drilling machine, namely, the positions of the upper separation device and the lower separation device are kept unchanged, so that the separation effect and the lengths of test and test sections are kept unchanged.
The invention has the beneficial effects that: the method is suitable for lithologic strata with high strength and stable structure, creatively drills the test section into an inverted truncated cone shape, adopts the upper separation device and the lower separation device with corresponding shapes to separate the upper end and the lower end of the test section, well realizes the separation of the test section from other sections, has simple principle and relatively convenient operation, has application value in the water pressure test, the fluid pressure test and the water pumping test of the test section drilled at any azimuth and inclination angle corresponding to any stratum level, and can pull out the upper separation device and the lower separation device after the test is completed to realize recovery.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a test section according to an embodiment of the present invention;
fig. 2 is a schematic diagram of mounting positions of an upper partition device and a lower partition device at a segment level according to an embodiment of the present invention.
Reference numerals illustrate:
1. a test section; 2. a drill rod; 3. an upper partition means; 4. a segmented horizon; 5. a flower tube; 6. and a lower separator.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Example 1
As shown in fig. 1 and 2, the method for carrying out the sectional isolation of water pressing, pressure measuring and water pumping drilling holes specifically comprises the following steps:
1) Constructing the corresponding drilling holes of the test section 1 into an inverted truncated cone shape according to the position requirement of the test section 1, and constructing other non-test sections 1 into a conventional cylinder shape; the specific method comprises the following steps: let test section 1 be located at depth H 1 To H 2 The position of the drilling hole is set as o point, and the hole depth is o to H 1 The section is constructed into a cylinder shape by adopting conventional drilling equipment, and the aperture is d 1 Access hole depth H 1 Total length H for time exchange 2 -H 1 Is consistent with the final pore-forming shape, and the outer diameter d of the bottom end of the drilling tool 2 The tip of the external channel d 1 Wherein d is 2 <d 1 Then the test section 1 is constructed to have a top diameter d 1 The diameter of the bottom is d 2 Is drilled in the shape of a reverse truncated cone, and the diameter d is adopted if required 2 Is used for constructing a cylindrical hole by a conventional drilling tool.
2) After the drilling construction is finished, reversely calculating the hole diameters of the upper end face and the lower end face of the segmented layer 4 according to the drilling depth of the position of the segmented layer 4 to be tested; the specific back calculation method comprises the following steps: such as layered layer at hole depth H 1 ' to H 2 ', wherein H 1 <H 1 ’<H 2 ’<H 2 The drilling hole diameters of the upper end face and the lower end face of the layering layer are respectively d 1 ' and d 2 'A'; d is then 1 ' and d 2 The' calculation formula is respectively:and->
3) The upper separating device 3 and the lower separating device 6 which are also inverted truncated cone-shaped are selected to seal the upper end face and the lower end face of the segmented layer 4 respectively, the upper separating device 3 and the lower separating device 6 are made of rubber with certain elasticity, the upper height and the lower height of the upper separating device 3 and the lower separating device 6 are respectively 0.5m, and the outer diameter of the lower end of the upper separating device 3 is d respectively 1 The external diameter of the upper end of the lower separation device 6 is d, which is' +10mm 2 ' 10mm; the upper separation device 3 and the lower separation device 6 are fixedly connected by adopting a high-strength flower pipe 5, the upper end of the flower pipe 5 passes through the upper separation device 3 and then is connected with the drill rod 2 and is communicated with the space in the drill rod 2, the flower pipe 5 is of a hollow structure, and a plurality of through holes are formed in the part of the flower pipe 5 between the upper separation device 3 and the lower separation device 6;
the descending length H1' -0.5m of the drill rod 2, and the outer diameter of the upper and lower separating devices 6 made of rubber is slightly larger than the bore diameter of the drill hole in the later stage of descending of the drill rod 2, so that additional pressure is required to be applied to the upper and lower separating devices 6 through the drill rod 2, and the descending length of the drill rod 2 is ensured; after the lowering is finished, the upper and lower separating devices 6 separate the drilling holes at the hole depths H2', H1', and the drilling holes H1 'to H2' sections form test and test sections separated from other layers;
4) After the sectional layer 4 to be tested is formed, carrying out a water pressure test, a fluid pressure test and a water pumping test on the test section and the test section through the space in the drill rod 2; when relevant tests and tests are carried out, the upper separation device 3 and the lower separation device 6 keep the descending length unchanged through the clamping and force application functions of the drilling machine, namely the positions of the upper separation device 3 and the lower separation device 6 are kept unchanged, so that the separation effect and the lengths of the test and test sections 1 are ensured to be unchanged
5) After the test is finished, the drill rod 2 is pulled out, the upper separating device 3 and the lower separating device 6 are pulled out for recycling, the drill holes can be restored to the original state, and the test work of any other segmented layer 4 are carried out according to the test requirement
Example 2
In the step 3), the drill rod 2 is adopted to replace the flower pipe 5, the drill rod 2 passes through the upper separating device 3 and is then fixed on the lower separating device 6, the upper separating device 3 is also fixed with the drill rod 2, a through hole for communicating the inner space of the part of the outer wall of the drill rod 2 between the upper separating device 3 and the lower separating device 6 is formed, and other steps are the same as those of the embodiment 1.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.