CN108104752B - Coring device and coring method for rock salt exploration engineering - Google Patents

Abstract

The invention provides a coring device and a coring method for rock salt exploration engineering, wherein the coring system comprises a drilling device, a coring device, a fisher, a winch device and a control device, the coring device comprises an outer pipe assembly and an inner pipe assembly, the outer pipe assembly is provided with a cavity in the extending direction, and the inner pipe assembly is arranged in the cavity and can move along the axial center line direction of the outer pipe assembly; the outer tube assembly comprises an upper joint, a spring clamping chamber, a stable joint, a reamer and a fourth drill bit which are connected in sequence; the inner pipe assembly comprises a spearhead, a spring clip, a recovery pipe, a single-action part adjustment, an inner pipe, a rectangular section, a clamp spring and a clamp spring seat which are connected in sequence. The invention provides a large-caliber rope coring device suitable for rock salt exploration engineering, a matched winch and other devices, and the winch is used for extracting an inner pipe and a rock core, so that the purpose of no lifting and coring is achieved.

Description

Coring device and coring method for rock salt exploration engineering

Technical Field

The invention relates to the field of rock salt exploration engineering, in particular to a coring device and a coring method for the rock salt exploration engineering.

Background

The rock salt exploration well is constructed for the exploration of the rock salt deposit, and the exploration well is required to drill and sample the rock core for testing according to the requirements of the national resource department (DZ/T0212-2002) for geological exploration of salt lakes and salt minerals, so as to obtain the grade of the salt deposit and the content of toxic and harmful elements. Meanwhile, the rock salt exploratory well is often combined with the construction of the brine production well, the caliber is large, and particularly the core-taking section is time-consuming and labor-consuming, and the drilling efficiency is low.

At present, the wire-line coring process is widely applied to small-caliber geological exploration construction, and an example of applying the large-caliber wire-line coring process to a coal-bed gas well is available at home and abroad, but no example of applying the large-caliber wire-line coring process to rock salt exploration drilling exists. If the wire-line coring process is popularized and applied to large-caliber rock salt exploration, the time for drilling and drilling can be reduced, the pure time utilization rate can be improved, the drilling efficiency can be improved, and the requirement of related specifications on coring can be met.

Disclosure of Invention

The invention aims to provide a coring device and a coring method for rock salt exploration engineering, and provides a large-caliber rope coring device and matched winch devices and the like suitable for the rock salt exploration engineering, wherein the winch is used for extracting an inner pipe and a rock core so as to achieve the purpose of not lifting the drill for coring.

To achieve the above object, the present invention refers to a coring system for rock salt exploration engineering, comprising a drilling device, a coring device, an fisher, a winch device, and a control device;

the drilling device comprises a first drilling tool for exploring holes into stable rock formations and a second drilling tool for exploring holes into salt layers, wherein the first drilling tool comprises a first drill bit, a first drill collar, a first drill rod and a first square drill rod which are sequentially connected, and the second drilling tool comprises a second drill bit, a second drill collar, a second drill rod and a second square drill rod which are sequentially connected;

the coring device comprises a third drill bit, a coring device, a third drill rod and a third drill rod which are connected in sequence;

the coring device comprises an outer tube assembly and an inner tube assembly, wherein the outer tube assembly is provided with a cavity in the extending direction, and the inner tube assembly is arranged in the cavity and can move along the axial center line direction of the outer tube assembly;

the outer tube assembly comprises an upper joint, a spring clamping chamber, a stable joint, a reamer and a fourth drill bit which are connected in sequence;

the inner pipe assembly comprises a spearhead, a spring clip, a recovery pipe, a single-action part adjustment, an inner pipe, a rectangular section, a clamp spring and a clamp spring seat which are connected in sequence;

the fisher is arranged in the hole and is positioned near the hole opening, the fisher is electrically connected with the control device, and vertically descends to the bottom of the hole along the hole at a set speed according to the instruction of the control device so as to fix the spearhead at the head of the spearhead;

the winch device comprises a winch and a steel wire rope, one end of the steel wire rope is coiled on a winding drum of the winch, and the other end of the steel wire rope is fixed at the tail of the fisher;

the winch device is electrically connected with the control device and is used for rotating the winding drum according to the instruction of the control device so as to apply a vertical upward extraction force on the fisher, so that the fisher carries the inner tube assembly to move along the axial center line of the outer tube assembly and separate from the outer tube assembly.

Further, the diameter of the first drill bit is larger than that of the second drill bit.

Further, the upper joint is provided with an inner step;

when the spring clip of the inner tube assembly props against the inner step of the upper joint, the gap between the end face of the snap spring seat and the drill bit is 3-4 mm.

Further, the upper part of the fisher is connected with a safety rope.

Further, the safety rope has a length of 1 meter and a diameter of 3 millimeters.

Further, the third drill bit adopts a PDC drill bit.

Furthermore, the third drill bit adopts a drill bit with small contact area of the bottom lip surface.

Further, the third drill bit adopts any one of a multi-water gap drill bit, a staggered lip face drill bit and a tooth-shaped structure drill bit.

Based on the foregoing coring system, the present invention also refers to a coring method for rock salt exploration engineering, comprising:

sequentially adopting a first drilling tool and a second drilling tool to open holes into the salt layer;

lowering the coring device into the hole, and continuously drilling until the core is filled with the inner tube;

extracting the coring device until the third drill bit leaves the bottom of the hole, clamping the rock core, and separating the third drill rod from the coring device to extract the hole;

lowering the fisher into the hole, lowering the fisher to the bottom of the hole at a set speed, contacting the spearhead, and fixing the spearhead to the head thereof;

starting a winch to rotate the winding drum so as to apply a vertical upward extraction force on the fisher, so that the fisher carries the inner tube assembly to move along the axial center line of the outer tube assembly and separate from the outer tube assembly until the inner tube assembly rises to the top of the hole;

and separating the fisher and the inner tube assembly to obtain the core.

Further, the method further comprises:

providing a spare inner tube assembly;

throwing the spare inner pipe assembly into a third drill rod from the top end of the hole, wherein the spare inner pipe assembly is connected with an on-machine drill rod;

and (3) pumping the spare inner pipe assembly to the inside of the outer pipe assembly in the spare inner pipe assembly inlet hole by starting the pump, and sweeping the hole to drill so as to fill the core with the inner pipe of the spare inner pipe assembly.

Compared with the prior art, the technical scheme of the invention has the remarkable beneficial effects that the large-caliber rope coring device suitable for rock salt exploration engineering and devices such as a matched winch are provided, and the inner pipe and the rock core are extracted by using the winch, so that the purpose of no lifting and coring is achieved.

It should be understood that all combinations of the foregoing concepts, as well as additional concepts described in more detail below, may be considered a part of the inventive subject matter of the present disclosure as long as such concepts are not mutually inconsistent. In addition, all combinations of claimed subject matter are considered part of the disclosed inventive subject matter.

The foregoing and other aspects, embodiments, and features of the present teachings will be more fully understood from the following description, taken together with the accompanying drawings. Other additional aspects of the invention, such as features and/or advantages of the exemplary embodiments, will be apparent from the description which follows, or may be learned by practice of the embodiments according to the teachings of the invention.

Drawings

The drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures may be represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. Embodiments of various aspects of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a schematic view of the structure of the corer of the present invention.

The spearhead is characterized by comprising the following components of a 1-fishing spearhead, a 2-snap stop, a 3-spring, a 4-positioning block, a 5-elastic cylindrical pin, a 6-finger spearhead, a 7-recovery pipe, an 8-elastic cylindrical pin, a 9-elastic cylindrical pin, a 10-spring, a 11-snap, a 12-rubber pad, a 13-elastic cylindrical pin, a 14-snap stop, a 15-elastic cylindrical pin, a 16-seat ring, a 17-suspension ring, a 18-snap ring, a 19-snap frame, a 20-adjusting nut, a 21-main pipe, a 22-steel pad, a 23-rubber pad, a 24-steel ball, a 25-bearing, a 26-bearing application, a 28-bearing, a 29-spring, a 31-packing nut, a 32-seat ring street head, a 33-outer pipe, a 34-bearing jacket, a 35-steel ball, a 37-steel ball application, a 38-reducer, a 39-inner pipe, a 40-lower joint, a 41-correction ring, a 42-snap ring, a 43-snap ring, a 44-snap spring seat and a 45-drill bit.

Detailed Description

For a better understanding of the technical content of the present invention, specific examples are set forth below, along with the accompanying drawings.

Aspects of the invention are described in this disclosure with reference to the drawings, in which are shown a number of illustrative embodiments. The embodiments of the present disclosure are not necessarily intended to include all aspects of the invention. It should be understood that the various concepts and embodiments described above, as well as those described in more detail below, may be implemented in any of a number of ways, as the disclosed concepts and embodiments are not limited to any implementation. Additionally, some aspects of the disclosure may be used alone or in any suitable combination with other aspects of the disclosure.

The invention refers to a coring system for rock salt exploration engineering, which comprises a drilling device, a coring device, an fisher, a winch device and a control device.

The drilling device comprises a first drilling tool for exploring holes into stable rock formations and a second drilling tool for exploring holes into salt layers, wherein the first drilling tool comprises a first drill bit, a first drill collar, a first drill rod and a first square drill rod which are sequentially connected, and the second drilling tool comprises a second drill bit, a second drill collar, a second drill rod and a second square drill rod which are sequentially connected.

The coring device comprises a third drill bit, a coring device, a third drill rod and a third drill rod which are sequentially connected.

An embodiment

Taking the rock salt mineral exploration of the mining area of the Feng county of Jiangsu province as an example, the stratum parameters are an ancient near-line official group, a recent line Feng county group and a fourth line loose layer, wherein the ancient near-line official group (Eg): the thickness is greater than 1300m, and the salt-containing stratum is formed.

The drillability of each rock stratum in the core section is shown in table 1, and the drilling parameters of one of the corresponding drilling devices are shown in table 2.

List of drillability of each formation in core section 1

The wellbore configuration for this embodiment is as shown in table 2 for the foregoing formation.

Well bore structure data table 2

Order of drilling	Well section	Drill bit size/mm	Sleeve size/mm	Casing depth/m
					One open	0～350	Φ311.1	Φ244.5	350
Two-way opening	350-final well	Φ215.9

The corresponding drill parameters may be designed as:

(1) One-open drilling tool combination

Phi 311.1mm drill bit + phi 165mm drill collar + phi 127mm drill pipe + phi 133mm kelly.

(2) Two-open drilling tool combination

Centerless drilling:

phi 215.9mm drill bit + phi 165mm drill collar x 1 + phi 127mm drill pipe + phi 133mm kelly. Core drilling:

phi 215.9mm drill bit + large caliber rope coring device + phi 127mm drill rod + phi 133mm square drill rod.

Before the drilling, flaw detection is carried out on all drilling tools, downhole tools and joints, so that the drilling tools with injuries are prevented from entering the well.

Preferably, the diameter of the first drill bit is greater than the diameter of the second drill bit.

Referring to fig. 1, the coring device includes an outer tube assembly having a cavity in an extension direction thereof and an inner tube assembly mounted within the cavity and movable along an axial centerline direction of the outer tube assembly.

The outer tube assembly comprises an upper joint, a spring clamping chamber, a stable joint, a reamer, a fourth drill bit and other devices which are connected in sequence.

The processing quality of the upper joint must be strict, the strength of the spring clip shifting fork is ensured, two steps at the top of the shifting block must be flat, and the two steps are ensured to be on the same plane, so that the spring clip is uniformly stressed. The use requirement of the drill bit and the reamer is the same as that of the common small caliber.

The inner pipe assembly comprises a spearhead, a spring clip, a recovery pipe, a single action part adjustment, an inner pipe, a rectangular section, a clamp spring seat and other devices which are connected in sequence.

The processing of the long grooves and the elastic shaft pin holes of all the elastic clamping frames must meet the drawing requirements, and all the elastic calipers must be symmetrical and flexible after being assembled to achieve free contraction and extension. The recovery pipe slides up and down flexibly, the bearing runs reliably, and the inner pipe must be kept straight.

The inner diameter of the drill bit and the free inner diameter of the clamp spring are reasonably matched, the free inner diameter of the clamp spring is about 0.3-0.5 mm smaller than the inner diameter of the drill bit, and if the free inner diameter of the clamp spring is too large, cores cannot be taken or blocked, so that the cores fall off in the middle or remain too much; too small, it is easy to cause core blockage. The airport should be equipped with 2-3 sizes of snap springs for selection, and the difference between the inner diameters of every two kinds is preferably 0.3 mm.

After the inner pipe assembly and the outer pipe assembly are assembled, the inner pipe assembly can be placed in the outer pipe assembly to form a complete set of rope core drilling tool, and the requirements are met:

A. the inner tube assembly should be unobstructed when placed from the upper portion of the outer tube assembly.

B. When the spring clip is propped against the inner step of the spring clip shifting fork (upper joint), the gap between the end surface of the clamp spring seat and the drill bit is preferably 3-4 mm. That is, the upper joint has an inner step.

When the spring clip of the inner tube assembly props against the inner step of the upper joint, the gap between the end face of the snap spring seat and the drill bit is 3-4 mm.

C. When the inner pipe assembly in the outer pipe assembly is fished in a trial manner by the fisher, the inner pipe assembly can be fished out smoothly.

The abrasion of the core tube exceeds 1/3 of the wall thickness, and the bending of the core tube exceeds 0.75 millimeter in each meter of length. Various drilling tools have tiny cracks, serious dents, screw wear or excessive movement, and should be repaired and replaced in time so as not to be used continuously.

When the core is taken out from the inner tube, the core tube is forbidden to be directly knocked by an iron hammer.

The fisher is arranged in the hole and is positioned near the hole opening, the fisher is electrically connected with the control device, and vertically descends to the bottom of the hole along the hole at a set speed according to the instruction of the control device so as to fix the spearhead at the head of the spearhead.

The fisher must be reliable in operation and firmly bound with the steel rope. In order to avoid damaging the steel wire rope when the salvaging is blocked, the upper part of the salvaging device is connected with a safety rope with the diameter of 3mm and the length of about one meter.

The fishing spear needs to be installed regularly and symmetrically, the tail spring works flexibly and reliably, and the head is opened by 5-10 mm.

The winch device comprises a winch and a steel wire rope, one end of the steel wire rope is coiled on a winding drum of the winch, and the other end of the steel wire rope is fixed at the tail of the fisher.

The tensile strength of the rock salt deposit rock is 1.12Mpa, the tensile strength of the rock is 2.5-4.4 Mpa, the diameter of the rock core is 74mm at maximum, the pulling force of the broken rock core is not more than 200kg, and other factors such as an inner tube of a coring device are considered, so that the lifting capacity of a matched winch and a steel wire rope is not more than 500kg.

The winch device is electrically connected with the control device and is used for rotating the winding drum according to the instruction of the control device so as to apply a vertical upward extraction force on the fisher, so that the fisher carries the inner tube assembly to move along the axial center line of the outer tube assembly and separate from the outer tube assembly.

And the third drill bit adopts a PDC drill bit.

Since the annular cutting area of the rope core drilling is larger than that of the conventional core drilling, the bit pressure used in the drilling process is correspondingly increased (PDC bit).

PDC bit rope coring drilling weight recommendation value table 3

Note that: 1 kg.apprxeq.10N.

The actual weight on bit is reasonably determined by practice according to specific stratum conditions, drill bit types, actual drill bit sizes (such as super-diameter drill bits) and the like. In order to reduce the bending of drilling and the weight of drilling, the rope coring drilling is preferably performed by using a drill bit with small contact area of the bottom lip surface, such as a drill bit with a multi-water gap, staggered lip surfaces and tooth-shaped structures, so that the weight of drilling required during drilling can be obviously reduced, and the inclined hole can be prevented.

As for the rotational speed of the coring device during drilling, as in the conventional diamond coring drilling, the higher rotational speed drilling is measured as much as possible under the conditions of pore diameter, pore depth, flushing lubrication conditions, pore wall stability, formation abrasiveness, drill rod firmness, equipment and the like.

Rope coring drilling is preferably carried out with a flushing fluid free of solid phase and low solid phase and with a lubricant when the conditions permit. When using mud, it is preferable to use high-quality clay as raw material to prevent mud skin from forming in drill rod. The determination of the amount of flushing liquid is two: (1) maintaining the upward flow velocity of the annular gap within the range of 0.45-1.0-1.5 m/s; (2) the flushing liquid amount per unit area (cm 2) of the bit lip surface is kept at 3-5L/min.

Flushing liquid

Based on the guiding thought of safely, high quality, low consumption and high efficiency in completing the construction task of the well, the slurry design of each well section of the well is as follows:

1. 0-250 m, adopting undispersed low solid-phase fresh water slurry, preparing base slurry by using high-quality bentonite, and adjusting the slurry performance by using sodium carbonate, hydrolyzed polyacrylamide (PHP) and Hydrolyzed Polyacrylonitrile (HPAM).

The stratum at the well section is soft, the drillability is good, the well wall is stable, the mud is focused on improving the capability of cleaning the bottom of the well and carrying rock powder, and the bit balling and mud cake sticking are prevented.

The mud properties are:

specific gravity: funnel viscosity of 1.08g/cm 3: 20 to 25s

Water loss: mud skin thickness less than or equal to 15ml/30 min: less than or equal to 1mm

pH value: 8-9 sand content: less than or equal to 3 percent

2. 250m to 700m, adjusting the performance of the slurry once every 30m to 50m of drilling, discharging partial slurry in the holes, and replacing new slurry to aim for the slurry performance index to reach the optimal state.

Specific gravity: funnel viscosity of 1.08-1.10 g/cm 3: 20 to 25s

Water loss: <10ml/30min mud skin thickness: less than or equal to 0.5mm

pH value: sand content 9-9.5: less than or equal to 2 percent

3. Salt-bearing formation interval mud type, performance and treatment:

when drilling and meeting the saline stratum, completely discharging fresh water mud in holes, replacing the saline mud, preparing base slurry by using brine and attapulgite salt-resistant soil, adding SMC, SMP, FCLS, K, na-CMC, sodium carbonate, caustic soda and the like to adjust the slurry performance, adding salt into the slurry to a saturated state, namely, the chloride ion content reaches 17-18 ten thousand PPM, and further carrying out anti-collapse treatment on the saturated saline mud to ensure that no blocking phenomenon exists in the well in the whole coring process.

Specific gravity: funnel viscosity of 1.25-1.30 g/cm 3: 30-25 s

Water loss: mud skin thickness 8ml/30 min: less than or equal to 0.5mm

pH value: sand content 9-10: less than or equal to 2 percent

(II) amount of flushing liquid

Flushing liquid quantity parameter meter

TABLE 4 Table 4

The invention also provides a coring method for rock salt exploration engineering, which adopts the coring system and comprises the following steps:

step 1, sequentially adopting a first drilling tool and a second drilling tool to open holes into the salt bed.

And step 2, lowering the coring device into the hole, and continuously drilling until the core is filled with the inner tube.

And 3, extracting the coring device until the third drill bit leaves the bottom of the hole, clamping the rock core, and separating the third drill rod from the coring device to extract the hole.

And 4, lowering the fisher into the hole, lowering the fisher to the bottom of the hole at a set speed, contacting the spear, and fixing the spear at the head of the spear.

And 5, starting a winch to rotate the winding drum so as to apply a vertical upward extraction force on the fisher, so that the fisher carries the inner tube assembly to move along the axial center line of the outer tube assembly and separate from the outer tube assembly until the inner tube assembly rises to the top of the hole.

And 6, separating the fisher and the inner tube assembly to obtain the core.

When the core is drilled to be filled with the inner pipe quickly (the length of the inner pipe is not excessively large) or the core is blocked, the core is salvaged immediately.

Firstly, lifting the drilling tool away from the bottom of the hole, clamping the rock core, lifting the drill rod on the machine, and unloading at the joint; the drilling machine is retreated, the drill rod thread protector is screwed on, the fisher is lowered, and the fisher descends in the flushing fluid at the speed of 1.5-2 m/s. Note the reaction of the fisher hooking the spearhead.

Judging whether the salvaging is successful or not, the following method can be referred to: one is whether a "bump-and-catch" sound is heard from the drill pipe at the port. When the hole is deep, the vertical shaft or the drill rod of the drilling machine can be tightly attached to the hole by means of a pipe wrench, a screw driver or an iron rod, and the hole is fine-heard by ears; secondly, whether the hand-pulled steel wire rope is stronger than before 'bumping clip'; thirdly, when the fisher is lifted up, whether slurry is gushed in the drill rod at the orifice is checked.

When the fishing hook of the fisher is confirmed to hook the fishing spear, the winch can be started to lift the inner pipe. After the fishing is successful, a mark is preferably made on the fishing wire rope for the next fishing reference.

When the inner pipe is taken out of the orifice, the fishing hook is disassembled and slowly lowered. So as to prevent the lower shaft adjusting part from bending.

When the inner pipe is not effective, the hard pier cannot be flushed, the reasons should be analyzed until the inner pipe is lifted, and the core taking condition is checked after the inner pipe is lifted.

In some examples, the inner tube is removed without core, and re-coring is needed.

The secondary coring method further comprises:

step 1, providing a standby inner pipe assembly.

And 2, throwing the standby inner pipe assembly into a third drill rod from the top end of the hole, wherein the standby inner pipe assembly is connected with an on-machine drill rod.

And 3, pumping the spare inner pipe assembly to the inside of the outer pipe assembly in the spare inner pipe assembly inlet hole by starting the pump, and sweeping the hole to drill so as to fill the core with the inner pipe of the spare inner pipe assembly.

The subsequent steps are the same as those of the coring method described above.

More than two sets of inner tube assemblies must be deployed at an airport. All inner tube assemblies must be consistent in length from the top of the spring caliper to the end of the clamp spring seat. The spare inner tube assembly should be placed in a place which is not easy to step on and be pressed, and the bearing is lubricated by grease.

When no core is confirmed in the drill string, the other set of spare inner pipe is put into the drill pipe through the hole, the drill pipe is put on the machine, the pump is started to pump the inner pipe so as to promote the inner pipe to slide downwards in an accelerating way, and in order to avoid being propped by the step part of the drill pipe joint in the sliding process, the drilling tool can be properly started to move.

When no flushing fluid exists in the drill string, the inner pipe is not thrown in. At this time, the drill rod on the machine is used for aligning with the orifice, pumping flushing liquid, rapidly throwing the inner tube after filling, and using a special dry hole throwing device if the water in the hole cannot be filled.

When the inner tube is confirmed to accurately and reliably reach the outer tube, the inner tube is accurately and slowly swept and drilled, and the sweeping hole is not allowed to drill before the inner tube reaches the bottom of the hole, so that a rock core is prevented from being prematurely put into a drill bit to prop the inner tube, and the rock core is not located at a preset position, and a phenomenon of 'pipe-punching' is formed, and at the moment, the spring clamping part of the inner tube is rapidly worn. Whether the inner pipe reaches the bottom of the hole or not can be judged according to different hole depths, drilling inclination angles and the nature searching rule of using flushing liquid, and experience is summarized and then specific time is regulated.

When no core or core deficiency is found in the inner tube after the core is fished, the reason should be judged. When the rock core is confirmed to fall in the drill string, the drill lifting treatment should be immediately carried out.

Once the drill rod is confirmed to be broken, the drill rod is not required to be put into the fisher to carry out the work of fishing the inner pipe.

The inner tube is screwed and disassembled by using special multi-contact free pliers; the clamp spring seat is screwed and disassembled by a special clamp spring seat spanner. Unscrewing any end (a snap spring seat or an inner tube joint) of the inner tube, lightly knocking the inner tube until the core is discharged, and not slapping by an iron hammer so as to prevent the core from being blocked when pit drilling is generated. The inner tube assembly is cleaned and inspected after the core is taken out, and then is reassembled, and the inner tube assembly is placed in a place which is not easy to be pressed and stepped on for next reuse.

Comparison of results with experimental data of common coring process

The large-caliber rope coring construction is carried out, the length of each time is about 2-4.8m, and the average length of each time is about 4.1 m. Compared with the common coring construction process, the drilling efficiency is improved by 65 percent.

For example, taking a mining area rock salt mine exploration by a Consumer, feng county, jiangsu, one mine is cored from 648.83m to 1011.76m by using a common coring process, the total construction time is 988.7 hours, the length of the core is 362.93m, and the core length is 203.47m, and the total drilling is carried out for 38 times. If the average drilling efficiency is 0.51m/h according to the large-caliber rope coring, 711.6 hours are needed, and 277.1 hours (11.5 days together) can be saved.

Therefore, the invention provides a coring device and a coring method for rock salt exploration engineering, and provides a large-caliber rope coring device and matched winch devices and the like suitable for the rock salt exploration engineering, wherein the winch is used for extracting an inner pipe and a rock core so as to achieve the purpose of not lifting the drill for coring.

While the invention has been described with reference to preferred embodiments, it is not intended to be limiting. Those skilled in the art will appreciate that various modifications and adaptations can be made without departing from the spirit and scope of the present invention. Accordingly, the scope of the invention is defined by the appended claims.

Claims (8)

1. A coring system for rock salt exploration engineering, which is characterized by comprising a drilling device, a coring device, a fisher, a winch device and a control device;

the drilling device comprises a first drilling tool for exploring holes into stable rock formations and a second drilling tool for exploring holes into salt layers, wherein the first drilling tool comprises a first drill bit, a first drill collar, a first drill rod and a first square drill rod which are sequentially connected, and the second drilling tool comprises a second drill bit, a second drill collar, a second drill rod and a second square drill rod which are sequentially connected; the diameter of the first drill bit is larger than that of the second drill bit;

the coring device comprises a third drill bit, a coring device, a third drill rod and a third drill rod which are connected in sequence;

the coring device comprises an outer tube assembly and an inner tube assembly, wherein the outer tube assembly is provided with a cavity in the extending direction, and the inner tube assembly is arranged in the cavity and can move along the axial center line direction of the outer tube assembly;

the outer tube assembly comprises an upper joint, a spring clamping chamber, a stable joint, a reamer and a fourth drill bit which are connected in sequence;

the inner pipe assembly comprises a spearhead, a spring clip, a recovery pipe, a single-action part adjustment, an inner pipe, a rectangular section, a clamp spring and a clamp spring seat which are connected in sequence;

the upper joint of the outer tube assembly is provided with an inner step; when the spring clamp of the inner pipe assembly props against the inner step of the upper joint, the gap between the end surface of the clamp spring seat and the fourth drill bit is 3-4 mm;

the fisher is arranged in the hole and is positioned near the hole opening, the fisher is electrically connected with the control device, and vertically descends to the bottom of the hole along the hole at a set speed according to the instruction of the control device so as to fix the spearhead at the head of the spearhead;

the winch device comprises a winch and a steel wire rope, one end of the steel wire rope is coiled on a winding drum of the winch, and the other end of the steel wire rope is fixed at the tail of the fisher;

the winch device is electrically connected with the control device and is used for rotating the winding drum according to the instruction of the control device so as to apply a vertical upward extraction force on the fisher, so that the fisher carries the inner pipe assembly to move along the axial center line of the outer pipe assembly and separate from the outer pipe assembly;

wherein the coring process includes:

sequentially adopting a first drilling tool and a second drilling tool to open holes into the salt layer;

lowering the coring device into the hole, and continuously drilling until the core is filled with the inner tube;

extracting the coring device until the third drill bit leaves the bottom of the hole, clamping the rock core, and separating the third drill rod from the coring device to extract the hole;

lowering the fisher into the hole, lowering the fisher to the bottom of the hole at a set speed, contacting the spearhead, and fixing the spearhead to the head thereof;

starting a winch to rotate the winding drum so as to apply a vertical upward extraction force on the fisher, so that the fisher carries the inner tube assembly to move along the axial center line of the outer tube assembly and separate from the outer tube assembly until the inner tube assembly rises to the top of the hole;

and separating the fisher and the inner tube assembly to obtain the core.

2. A coring system for a rock salt exploration project according to claim 1 wherein said latch jack has a safety line connected to an upper portion thereof.

3. A coring system for use in rock salt exploration engineering according to claim 2, wherein said safety line is 1 meter in length and 3 millimeters in diameter.

4. The coring system for a rock salt exploration project of claim 1, wherein said third bit is a PDC bit.

5. A coring system for use in rock salt exploration engineering according to claim 1, wherein said third bit is a bit having a small contact area with the bottom lip surface.

6. The coring system for a rock salt exploration project of claim 5, wherein said third bit is any one of a multiple nozzle bit, a staggered lip bit, and a tooth form structured bit.

7. A coring method for a rock salt exploration project employing the coring system of claim 1, comprising:

sequentially adopting a first drilling tool and a second drilling tool to open holes into the salt layer;

lowering the coring device into the hole, and continuously drilling until the core is filled with the inner tube;

extracting the coring device until the third drill bit leaves the bottom of the hole, clamping the rock core, and separating the third drill rod from the coring device to extract the hole;

lowering the fisher into the hole, lowering the fisher to the bottom of the hole at a set speed, contacting the spearhead, and fixing the spearhead to the head thereof;

starting a winch to rotate the winding drum so as to apply a vertical upward extraction force on the fisher, so that the fisher carries the inner tube assembly to move along the axial center line of the outer tube assembly and separate from the outer tube assembly until the inner tube assembly rises to the top of the hole;

and separating the fisher and the inner tube assembly to obtain the core.

8. The coring method for a rock salt exploration project of claim 7, further comprising:

providing a spare inner tube assembly;

throwing the spare inner pipe assembly into a third drill rod from the top end of the hole, wherein the spare inner pipe assembly is connected with an on-machine drill rod;

and (3) pumping the spare inner pipe assembly to the inside of the outer pipe assembly in the spare inner pipe assembly inlet hole by starting the pump, and sweeping the hole to drill so as to fill the core with the inner pipe of the spare inner pipe assembly.