阅读说明：本技术 适用于泥化夹层地层的清水钻进取芯方法 (Clear water drilling coring method suitable for argillized interlayer stratum ) 是由 张书磊 李清波 葛字家 缪绪樟 王栋 宋海印 曹雪然 王亚猛 李文帝 吕万宏 孙 于 2021-08-23 设计创作，主要内容包括：本发明公开了一种适用于泥化夹层地层的清水钻进取芯方法,包括：第一步,将钻具下入孔内,保持钻速150-450r/min,钻压5-15KN,泵量70-150L/min,当钻具进尺达到岩芯衬管长度时,停止钻进,将钻具提至孔外；第二步,通过人工取芯方式或水压取芯方式拆卸岩心；前者为：①将侧喷PDC钻头、扩孔器、外管的第一短接一同拆解②将卡簧座、内管一同拆解,露出衬管③采用人工抽出衬管,取出岩芯；后者为：①拆卸侧喷PDC钻头②拆卸外管、扩孔器③将水力退芯接头与内管、衬管、卡簧座一同拆卸④拆卸卡簧座⑤将水管与水力退芯接头连接起来,利用水压使岩芯退出内管。本发明能够提高泥化夹层取芯率和满足取芯质量的需要,在不要泥浆保护的前提下,实现采取岩芯率达到95%以上的目标。(The invention discloses a clear water drilling coring method suitable for a argillized interlayer stratum, which comprises the following steps: firstly, a drilling tool is put into a hole, the drilling speed is kept at 150-; secondly, disassembling the rock core in a manual coring mode or a hydraulic coring mode; the former is: firstly, disassembling a side-spraying PDC drill bit, a reamer and a first short circuit of an outer pipe together, disassembling a snap spring seat and an inner pipe together to expose a liner pipe, and manually drawing out the liner pipe to take out a rock core; the latter is: the method comprises the steps of firstly, disassembling a side-spraying PDC drill bit, secondly, disassembling an outer pipe and a reamer, thirdly, disassembling a hydraulic core withdrawing joint together with an inner pipe, a liner pipe and a clamp spring seat, fourthly, disassembling a clamp spring seat, fifthly, connecting a water pipe with the hydraulic core withdrawing joint, and withdrawing a rock core from the inner pipe by utilizing water pressure. The invention can improve the core-taking rate of the argillization interlayer and meet the requirement of core-taking quality, and the aim that the core-taking rate reaches more than 95 percent is achieved on the premise of not protecting slurry.)

1. A clear water drilling coring method suitable for argillization interlayer stratum is characterized by comprising the following steps: the method comprises the following steps:

step one, when meeting the working condition of a argillization interlayer stratum, a drilling tool is lowered into a hole, the drilling speed is kept at 150-;

the drilling tool comprises an open powder taking pipe, a drill rod joint, a sand setting sleeve, a four-purpose joint, an outer pipe, a reamer and a side-jet PDC drill bit which are sequentially connected, wherein the four-purpose joint is provided with an upper end inner cavity and a lower end inner cavity, a first water hole communicated with the sand setting sleeve and the outer pipe is formed in the bottom of the upper end inner cavity, a first one-way valve is arranged in the upper end inner cavity and connected with a filter core pipe positioned in the sand setting sleeve, a single-action pair is arranged in the lower end inner cavity, the other end of the single-action pair is connected with an adjusting assembly with a second water hole and a second one-way valve, the lower end of the adjusting assembly is connected with an inner pipe through a hydraulic core withdrawing joint, a liner pipe is arranged in the inner pipe, and a clamp spring seat connected with the side-jet PDC drill bit in a clamping mode is arranged at the lower end of the inner pipe;

secondly, detaching the core from the drilling tool in a manual coring mode or a hydraulic coring mode;

the manual coring method comprises the following steps: firstly, disassembling a side-spraying PDC drill bit, a reamer and a first short circuit of an outer pipe together; secondly, disassembling the clamp spring seat and the inner pipe together to expose the liner pipe; thirdly, manually drawing out the liner tube and taking out the core;

the hydraulic coring method comprises the following steps: firstly, disassembling a side-spraying PDC drill bit; disassembling the outer pipe and the reamer; thirdly, the hydraulic core-withdrawing joint, the inner pipe, the liner pipe and the clamp spring seat are disassembled together; fourthly, disassembling the clamp spring seat; connecting the water pipe with the hydraulic core withdrawing joint, and withdrawing the core from the inner pipe by using water pressure.

2. The clean water drilling and coring method suitable for argillaceous interbedded formations according to claim 1, wherein: and a plurality of longitudinally arranged hard alloy strips are embedded and welded on the outer wall of the four-way joint, and the maximum outer diameter of each hard alloy strip is consistent with the maximum outer diameter of the reamer.

3. The clean water drilling and coring method suitable for argillaceous interbedded formations according to claim 1, wherein: the single action pair comprises a mandrel and a rotating assembly connected with the mandrel, the rotating assembly is symmetrically arranged at two ends of the mandrel, each rotating assembly comprises a sleeve used for connecting a lower end inner cavity of a four-purpose joint or the upper end of an adjusting assembly, the sleeve is arranged on the mandrel in a penetrating mode, a rolling bearing and a pressure bearing are arranged between the sleeve and the mandrel, an oil filling hole between the rolling bearing and the pressure bearing is formed in the sleeve, one end, close to the rolling bearing, of the sleeve is fixed through a nut, and one end, close to the pressure bearing, of the sleeve is fixed through an end cover.

4. The clean water drilling and coring method suitable for argillaceous interbedded formations according to claim 1, wherein: the adjusting assembly comprises an adjusting bolt, a threaded inner cavity used for connecting a single acting pair is formed in the upper end of the adjusting bolt, a vertical cavity with a downward opening is formed in the lower end of the adjusting bolt, the vertical cavity and the horizontal cavity are formed in the middle of the adjusting bolt, the second water hole is communicated, the second one-way valve is installed on the inner side of the vertical cavity, and a threaded joint and a threaded positioning piece are sleeved on the outer side of the vertical cavity.

5. The clean water drilling and coring method suitable for argillaceous interbedded formations according to claim 1, wherein: the outer pipe is formed by connecting a first main pipe and a first short joint in a threaded manner.

6. The clean water drilling and coring method suitable for argillaceous interbedded formations according to claim 1, wherein: the inner pipe is formed by connecting a second main pipe with a second short joint in a threaded manner.

7. The clean water drilling and coring method suitable for argillaceous interbedded formations according to claim 6, wherein: the liner tube is a semi-closed tube connected through snap fasteners.

8. The clean water drilling and coring method suitable for argillaceous interbedded formations according to claim 1, wherein: the side-spraying PDC drill bit comprises a reducing steel pipe, a third water hole is formed in the reducing position of the reducing steel pipe in the vertical direction, and a PDC composite sheet is arranged at the front end of the reducing steel pipe and close to the third water hole.

Technical Field

The invention relates to the technical field of hydraulic engineering exploration drilling tools, in particular to a clear water drilling coring method suitable for argillized interlayer strata.

Background

The argillization interlayer is an interlayer which is formed by breaking an original thin layer argilliferous rock stratum in the original rock by structure-to-structure dislocation and is loose in structure, weak in inter-granular connection and completely argillized under the long-term physicochemical action of underground water. Its existence brings serious threat to the stability of various rock mass engineering. Thus, argillized interlayers are one of the necessary items in significant hydroelectric surveys. As the drilling operation process of the water conservancy and hydropower industry does not allow the use of slurry with the core protection effect, only the clear water is allowed to be used as the drilling flushing fluid, and the coring difficulty is increased.

The existing common argillization interlayer clear water drilling core drill bit is of a single-action double-pipe structure, the single-action structure adopts a multi-group thrust bearing combination mode, core pipe vibration, core deviation and wall leaning are easy to generate, the single action of the core pipe is reduced, the cores are oppositely ground, and the like; secondly, the inner pipe is in a half-closed pipe form, and flushing fluid in an annular gap between the inner pipe and the outer pipe easily enters the inside of the half-closed pipe along the gap between the half-closed pipes to flush rocks; thirdly, the bottom of the drilling tool is provided with a reamer, so that the drilling tool is in a single-point stress state at the bottom of the hole, and the drilling tool at the bottom of the hole is easy to vibrate; fourthly, the drill bit selected by the conventional single-action double-tube group drilling tool has the problems that flushing liquid flows out of the drill bit after passing through a clamp spring seat and is easy to erode to enter the drill bit or a argillized base layer core in front of the drill bit; fifthly, when the clean water is used as flushing fluid, the powder carrying capacity is weaker, and buried drilling and stuck drilling accidents are easy to occur when a conventional drilling tool is used for drilling a rock core.

Disclosure of Invention

In order to solve the problems, the invention provides a clear water drilling and coring method suitable for a argillized interlayer stratum, which can specifically adopt the following technical scheme:

the invention relates to a clear water drilling coring method suitable for a argillized interlayer stratum, which comprises the following steps of:

step one, when meeting the working condition of a argillization interlayer stratum, a drilling tool is lowered into a hole, the drilling speed is kept at 150-;

the drilling tool comprises an open powder taking pipe, a drill rod joint, a sand setting sleeve, a four-purpose joint, an outer pipe, a reamer and a side-jet PDC drill bit which are sequentially connected, wherein the four-purpose joint is provided with an upper end inner cavity and a lower end inner cavity, a first water hole communicated with the sand setting sleeve and the outer pipe is formed in the bottom of the upper end inner cavity, a first one-way valve is arranged in the upper end inner cavity and connected with a filter core pipe positioned in the sand setting sleeve, a single-action pair is arranged in the lower end inner cavity, the other end of the single-action pair is connected with an adjusting assembly with a second water hole and a second one-way valve, the lower end of the adjusting assembly is connected with an inner pipe through a hydraulic core withdrawing joint, a liner pipe is arranged in the inner pipe, and a clamp spring seat connected with the side-jet PDC drill bit in a clamping mode is arranged at the lower end of the inner pipe;

secondly, detaching the core from the drilling tool in a manual coring mode or a hydraulic coring mode;

the manual coring method comprises the following steps: firstly, disassembling a side-spraying PDC drill bit, a reamer and a first short circuit of an outer pipe together; secondly, disassembling the clamp spring seat and the inner pipe together to expose the liner pipe; thirdly, manually drawing out the liner tube and taking out the core;

the hydraulic coring method comprises the following steps: firstly, disassembling a side-spraying PDC drill bit; disassembling the outer pipe and the reamer; thirdly, the hydraulic core-withdrawing joint, the inner pipe, the liner pipe and the clamp spring seat are disassembled together; fourthly, disassembling the clamp spring seat; connecting the water pipe with the hydraulic core withdrawing joint, and withdrawing the core from the inner pipe by using water pressure.

And a plurality of longitudinally arranged hard alloy strips are embedded and welded on the outer wall of the four-way joint, and the maximum outer diameter of each hard alloy strip is consistent with the maximum outer diameter of the reamer.

The single action pair comprises a mandrel and a rotating assembly connected with the mandrel, the rotating assembly is symmetrically arranged at two ends of the mandrel, each rotating assembly comprises a sleeve used for connecting a lower end inner cavity of a four-purpose joint or the upper end of an adjusting assembly, the sleeve is arranged on the mandrel in a penetrating mode, a rolling bearing and a pressure bearing are arranged between the sleeve and the mandrel, an oil filling hole between the rolling bearing and the pressure bearing is formed in the sleeve, one end, close to the rolling bearing, of the sleeve is fixed through a nut, and one end, close to the pressure bearing, of the sleeve is fixed through an end cover.

The adjusting assembly comprises an adjusting bolt, a threaded inner cavity used for connecting a single acting pair is formed in the upper end of the adjusting bolt, a vertical cavity with a downward opening is formed in the lower end of the adjusting bolt, the vertical cavity and the horizontal cavity are formed in the middle of the adjusting bolt, the second water hole is communicated, the second one-way valve is installed on the inner side of the vertical cavity, and a threaded joint and a threaded positioning piece are sleeved on the outer side of the vertical cavity.

The outer pipe is formed by connecting a first main pipe and a first short joint in a threaded manner.

The inner pipe is formed by connecting a second main pipe with a second short joint in a threaded manner.

The liner tube is a semi-closed tube connected through snap fasteners.

The side-spraying PDC drill bit comprises a reducing steel pipe, a third water hole is formed in the reducing position of the reducing steel pipe in the vertical direction, and a PDC composite sheet is arranged at the front end of the reducing steel pipe and close to the third water hole.

The clear water drilling coring method suitable for the argillized interlayer stratum provided by the invention uses the specially designed drilling tool, can improve the argillized interlayer coring rate and meet the coring quality requirement in the argillized interlayer stratum drilling construction, and realizes the aim of adopting the core rate of more than 95% on the premise of not protecting slurry. Compared with the prior art, it has following advantage:

1) the combined design of the open type powder taking pipe and the sand setting pipe can effectively reduce the probability of the problems of drill burying and drill clamping caused by insufficient powder carrying capacity of clear water in the drilling process;

2) the side-jetting PDC drill bit is designed, so that the scouring of clear water to a rock core is remarkably reduced, and the side-jetting PDC drill bit can be applied to a argillization interlayer stratum and other weak and easily-eroded strata;

3) the four-purpose catcher of the reaming structure is arranged at the upper end of the drilling tool and is used in combination with the reamer at the lower end of the drilling tool, so that the stress structure of the drilling tool in the hole is changed, and the stability and the pilot performance of the drilling tool are improved;

4) the core inner tube and the single-acting mechanism have the advantages that the core inner tube and the single-acting mechanism are in the same core degree and single-acting performance are improved by adopting the single-acting structure consisting of the thrust bearing and the rolling bearing;

5) the drilling tool adopts a three-layer pipe structure consisting of an outer pipe, an inner pipe and a liner pipe, wherein the inner pipe adopts a full pipe structure, so that the erosion effect of flushing fluid in the annular clearance between the inner pipe and the outer pipe in the conventional single-action double-pipe structure (the inner pipe is a half-pipe-closing mechanism) on a rock core can be effectively avoided; meanwhile, the lower ends of the outer pipe and the inner pipe of the drilling tool are respectively provided with a short circuit, so that a mechanical core discharging mode can be adopted, the working procedure of disassembling a core is reduced, and the construction efficiency is improved;

6) the upper rock stratum and the lower rock stratum of the argillization interlayer rock core have certain strength, and the mode that the clamp spring is clamped to break the rock core is selected, so that the argillization interlayer can be protected.

Drawings

Fig. 1 is a schematic view of the structure of the drilling tool of the present invention.

Fig. 2 is a schematic structural view of the four-way joint of fig. 1.

Fig. 3 is a schematic structural view of the single acting pair in fig. 1.

Fig. 4 is a schematic view of the structure of the adjustment assembly of fig. 1.

FIG. 5 is a schematic structural diagram of the side-jet PDC bit of FIG. 1.

Fig. 6 is a schematic view of the structure of the tube of fig. 1.

Fig. 7 is a schematic structural view of the inner tube of fig. 1.

Figure 8 is a schematic view of the liner of figure 1.

Detailed Description

The following describes embodiments of the present invention in detail with reference to the drawings, and the embodiments are implemented on the premise of the technical solution of the present invention, and detailed embodiments and specific construction processes are given, but the scope of the present invention is not limited to the following embodiments.

As shown in fig. 1-8, the method for coring in clear water suitable for argillaceous interbedded formations of the present invention comprises the following steps:

step one, when meeting the working condition of a argillization interlayer stratum, a drilling tool is lowered into a hole, the drilling speed is kept at 150-;

the drilling tool comprises an open powder taking pipe 1, a drill rod joint 2, a sand setting sleeve 3, a four-purpose joint 4, an outer pipe 5, a reamer 6 and a side-spraying PDC drill bit 7 which are sequentially connected in a threaded manner, wherein the four-purpose joint 4 is provided with an upper end inner cavity and a lower end inner cavity, a first water hole 401 communicated with the sand setting sleeve 3 and the outer pipe 5 is formed in the bottom of the upper end inner cavity, a first one-way valve 402 is installed in the upper end inner cavity, the first one-way valve 402 is connected with a filter core pipe 403 located in the sand setting sleeve 3, a single-action pair 8 is connected in the lower end inner cavity in a threaded manner, an adjusting component 9, a hydraulic core withdrawing joint 10 and an inner pipe 11 are sequentially connected in a threaded manner at the other end of the single-action pair 8, a liner pipe 12 is connected in the inner pipe 11 in a sleeved manner, and a clamp spring seat 13 connected with the side-spraying PDC drill bit 7 in a clamped manner is connected in a threaded manner at the lower end of the inner pipe 11.

A plurality of longitudinally arranged cemented carbide strips 404 are bonded to the outer wall of the four-way joint 4, and the maximum outer diameter of the cemented carbide strips 404 coincides with the maximum outer diameter of the reamer 6.

The single-acting pair 8 comprises a mandrel 801 and two rotating assemblies connected with the mandrel 801, the rotating assemblies are symmetrically arranged at two ends of the mandrel 801, each rotating assembly comprises a sleeve 802 which is screwed in an inner cavity at the lower end of the four-way joint 4 or an inner cavity at the upper end of the adjusting assembly 9, the sleeve 802 penetrates through the mandrel 801, a rolling bearing 803 and a pressure bearing 804 are arranged between the sleeve 802 and the mandrel 801, an oil filling hole 805 which is located between the rolling bearing 803 and the pressure bearing 804 is formed in the sleeve 802, one end, close to the rolling bearing 803, of the sleeve 802 is fixed through a nut 806 and a gasket 807, one end, close to the pressure bearing 804, of the sleeve 802 is fixed through an end cover 808, and an oil seal 809 is arranged between the end cover 808 and the mandrel 801.

The adjusting assembly 9 comprises an adjusting bolt 901, a thread inner cavity used for connecting the single-action pair 8 is formed in the upper end of the adjusting bolt 901, a vertical cavity with a downward opening is formed in the lower end of the adjusting bolt 901, the vertical cavity is communicated with a second water hole 902 formed in the middle of the adjusting bolt 901 in a horizontal mode, a second one-way valve 903 is installed on the inner side of the vertical cavity, and a threaded connector 904 and a thread positioning piece 905 are sleeved on the outer side of the vertical cavity.

The outer pipe 5 is formed by screwing a first main pipe 501 and a first short joint 502; the inner pipe 11 is formed by screwing a second main pipe 111 and a second short joint 112; liner 12 is a semi-closed tube connected by snap fasteners.

The side-spraying PDC drill bit 7 comprises a reducing steel pipe 701, a third water hole 702 is formed in the reducing position of the reducing steel pipe 701 in the vertical direction, and a plurality of PDC composite sheets 703 are uniformly embedded at the front end of the reducing steel pipe 701 and the position close to the third water hole 702.

Secondly, disassembling the core from the drilling tool in a manual core taking mode or a hydraulic core taking mode:

the manual coring method comprises the following steps: firstly, disassembling a side-jetting PDC drill bit 7, a reamer 6 and a first short circuit 502 of an outer pipe 5 together; disassembling the clamp spring seat 13 and the inner pipe 11 together to expose the liner pipe 12; thirdly, the liner tube 12 is drawn out manually, and the core is taken out.

The hydraulic coring method comprises the following steps: firstly, disassembling a side-spraying PDC drill bit 7; disassembling the outer pipe 5 and the reamer 6; thirdly, the hydraulic core-withdrawing joint 10, the inner pipe 11, the liner pipe 12 and the clamp spring seat 13 are disassembled together; fourthly, disassembling the clamp spring seat 13; connecting the water pipe with the hydraulic core withdrawing joint 10, and withdrawing the core from the inner pipe 11 by using the water pressure.

It should be noted that in the description of the present invention, terms of orientation or positional relationship such as "front", "rear", "left", "right", "vertical", "horizontal", "inner", "outer", etc., are based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.