CN114412369A - Double-layer grouting drill rod - Google Patents

Abstract

The invention discloses a double-layer grouting drill rod, which comprises: the outer tube and insert locate in the outer tube rather than the inner tube with the axle center, threaded connection between inner tube and the outer tube, the middle part through-hole of inner tube is interior passageway, the clearance between the inner wall of outer tube and the outer wall of inner tube is outer passageway, the back end of outer tube is equipped with connects internal thread and concentric position sleeve, the anterior segment of outer tube be equipped with be connected internal thread assorted connection external screw thread and with the concentric position sleeve assorted concentric position axle, with when a plurality of double-deck slip casting drilling rods are connected, realize being connected through connecting the internal thread and being connected the external screw thread, and realize concentric axiality through concentric position sleeve and concentric position axle.

Description

Double-layer grouting drill rod

Technical Field

The invention relates to the technical field of drilling machine equipment, in particular to a grouting drill rod.

Background

The existing small-diameter drill rod is manufactured by a single outer pipe, double-slurry filling cannot be achieved, in order to achieve double-slurry filling, the drill rod is formed by assembling an inner pipe and the outer pipe, the diameter of the drill rod is large, and the drilling difficulty is improved. And the drift diameter of the inner pipe of the existing double-liquid grouting drill rod is very small, the working efficiency is very low, and the requirement of a user cannot be met.

For example, the drill rod disclosed in chinese patent application No. 201920381570.8 is a dual-channel structure, in which the drill rod is inserted into the central through hole of the outer tube of the drill rod, the middle through hole of the inner tube of the drill rod is a first transmission channel, and the annular gap between the outer circumferential surface of the inner tube of the drill rod and the inner circumferential surface of the outer tube of the drill rod is a second transmission channel. However, the following disadvantages or shortcomings still exist in the present invention: (1) the drift diameter of a second transmission channel of the double-liquid grouting drill rod is narrow, so that the actual grouting requirement is difficult to meet; (2) and the connection firmness of the inner pipe and the outer pipe of the drill rod is not high.

Therefore, the problem that the double-layer grouting drill rod with the large drift diameter of the inner channel and the outer channel, the high grouting working efficiency and the firm connection of the drill rod is urgently needed to be solved in the industry is provided.

Disclosure of Invention

The invention aims to provide a double-layer grouting drill rod, which can control the length of the drill rod, has larger drift diameters of an inner channel and an outer channel and has high grouting work efficiency.

In order to achieve the above object, the present invention provides a double-layer grouting drill rod, comprising: the outer tube and insert locate in the outer tube rather than the inner tube with the axle center, threaded connection between inner tube and the outer tube, the middle part through-hole of inner tube is interior passageway, the clearance between the inner wall of outer tube and the outer wall of inner tube is outer passageway, the back end of outer tube is equipped with connects internal thread and concentric position sleeve, the anterior segment of outer tube be equipped with be connected internal thread assorted connection external screw thread and with the concentric position sleeve assorted concentric position axle, with when a plurality of double-deck slip casting drilling rods are connected, realize being connected through connecting the internal thread and being connected the external screw thread, and realize concentric axiality through concentric position sleeve and concentric position axle.

Optionally, the outer tube is including the outer tube tail section, outer tube middle section and the outer tube anterior segment that connect gradually, and the inner tube is including the inner tube tail section, inner tube middle section and the inner tube anterior segment that connect gradually, inner tube anterior segment and outer tube anterior segment threaded connection.

Optionally, the inside of outer tube back end is the step through-hole, include the outer tube back end afterbody that the internal diameter reduced in proper order forward from the back, outer tube back end middle part and outer tube back end are anterior, the inner wall processing of outer tube back end afterbody has the connection internal thread, the inner wall at outer tube back end middle part is equipped with concentric position sleeve, the anterior front end of outer tube back end is equipped with the first locating flange of outer tube, first locating hole is processed into to the anterior inner wall of outer tube back end, be on a parallel with outer tube the central axis direction and be equipped with the first through-hole of a plurality of between anterior inner wall of outer tube back end and the outer wall, in order to form the back end of outer passageway.

Preferably, 6-12 through holes which are distributed at equal intervals along the circumferential direction of the outer pipe are drilled between the inner wall and the outer wall of the front part of the tail section of the outer pipe in the direction parallel to the central axis of the outer pipe.

Preferably, 8 through holes which are distributed at equal intervals along the peripheral direction of the outer pipe are drilled between the inner wall and the outer wall of the front part of the tail section of the outer pipe in the direction parallel to the central axis of the outer pipe.

Optionally, the internal perisporium of outer tube middle section and the first location flange phase-match of outer tube back end, the first location flange of outer tube is inserted and is located in the intraductal of outer tube middle section to realize that the location of outer tube middle section and outer tube back end is connected. The annular gap between the inner peripheral wall of the outer tube middle section and the outer peripheral wall of the inner tube middle section forms a middle section of the outer channel, and the middle section of the outer channel is communicated with the tail section of the outer channel.

Optionally, the tail end of the outer tube front section is provided with an outer tube second positioning flange, the outer tube second positioning flange is matched with the inner peripheral wall of the outer tube middle section, and the outer tube second positioning flange is inserted into the tube arranged in the outer tube middle section so as to realize the positioning connection of the outer tube front section and the outer tube middle section.

Preferably, the front end of the front part of the tail section of the outer tube is provided with a first conical surface of the outer tube, the tail end of the middle section of the outer tube is provided with a second conical surface of the outer tube, the front end of the middle section of the outer tube is provided with a third conical surface of the outer tube, a first V-shaped annular groove of the outer tube is formed between the first conical surface of the outer tube and the second conical surface of the outer tube, and the first V-shaped annular groove of the outer tube is welded or a bonding agent is applied to realize the fixed connection of the middle section of the outer tube and the tail section of the outer tube.

Preferably, the tail end of the front section of the outer tube is provided with a fourth conical surface of the outer tube, a second V-shaped ring groove of the outer tube is formed between the third conical surface of the outer tube and the fourth conical surface of the outer tube, and the second V-shaped ring groove of the outer tube is welded or is bonded to realize the fixed connection of the front section of the outer tube and the middle section of the outer tube.

Optionally, the inner part of the front section of the outer tube is provided with a step through hole, the tail part of the front section of the outer tube, the middle part of the front section of the outer tube and the front part of the front section of the outer tube are sequentially reduced in inner diameter from back to front, a plurality of second through holes are arranged between the inner wall and the outer wall of the front section of the outer tube in a direction parallel to the central axis of the outer tube to form the front section of the outer channel, and the front section of the outer channel is communicated with the middle section of the outer channel; the inner wall of the middle part of the front section of the outer pipe is provided with outer pipe internal connecting threads for connecting and fixing the inner pipe in a threaded manner.

Preferably, 6-12 through holes which are distributed at equal intervals along the circumferential direction of the outer pipe are drilled between the inner wall and the outer wall of the front section of the outer pipe in a direction parallel to the central axis of the outer pipe.

Preferably, 8 through holes which are distributed at equal intervals along the peripheral direction of the outer pipe are drilled between the inner wall and the outer wall of the front section of the outer pipe and are parallel to the central axis direction of the outer pipe.

Preferably, the tail part of the front section of the outer pipe is manufactured into a flared opening, so that the front end of the inner pipe is inserted into the tail part of the front section of the outer pipe during installation.

Optionally, the outside of the outer tube front section is roughly a four-step ladder shape with gradually reduced outer diameter, the first step corresponds to the tail of the outer tube front section and the middle of the outer tube front section, the front end face of the first step is provided with a first sealing groove for installing a sealing ring, the connecting external thread is arranged at the outer wall of the second step, the concentric positioning shaft is arranged at the third step, the fourth step forms an inner tube positioning flange, and the outer wall of the front end of the fourth step is provided with a second sealing groove for installing a sealing ring.

Optionally, the inside of inner tube tail section is the step through-hole, includes inner tube tail section afterbody, inner tube tail section middle part and the inner tube tail section front portion that the internal diameter reduces in proper order from back to front, and wherein, the inner wall processing in inner tube tail section middle part has the screw thread for the dismantlement.

Preferably, the inner bore of the tail section of the inner tube is cylindrical.

Alternatively, the outer portion of the inner tube tail section is in a three-step shape with gradually reduced outer diameter, the first step surrounds the periphery of the whole inner tube tail section tail and the periphery of about half of the inner tube tail section middle portion, the second step surrounds the periphery of the other half of the inner tube tail section middle portion and the periphery of most of the inner tube tail section front portion, and the third step surrounds the periphery of the rest of the inner tube tail section front portion.

Optionally, the front end face of the first step forms a clamping table, and when the inner pipe is installed in the outer pipe, the clamping table is abutted against the rear end face of the front part of the tail section of the outer pipe to limit the inner pipe relative to the outer pipe, the outer wall of the second step is provided with a third sealing groove for installing a sealing ring, and a first positioning flange of the inner pipe and a first conical surface of the inner pipe are formed at the third step.

Preferably, the outer portion of the first step may be provided with a square or hexagonal shape for rotatably mounting the inner pipe by using a socket wrench.

Optionally, the tail end of the inner tube middle section is provided with an inner tube second conical surface, the inner peripheral wall of the inner tube middle section is matched with the inner tube first positioning flange of the inner tube tail section, the inner tube first positioning flange of the inner tube tail section is inserted into the tube arranged at the inner tube middle section to realize the positioning connection of the inner tube middle section and the inner tube tail section, a first inner tube V-shaped annular groove is formed between the inner tube first conical surface and the inner tube second conical surface, the first inner tube V-shaped annular groove is welded or a binder is applied to realize the fixed connection of the inner tube middle section and the inner tube tail section, and the front end of the inner tube middle section is provided with an inner tube third conical surface to realize the fixed connection of the inner tube middle section and the inner tube front section.

Optionally, the tail end of the inner tube front section is provided with an inner tube second positioning flange and an inner tube fourth conical surface, the inner tube second positioning flange is matched with the inner peripheral wall of the inner tube middle section, the inner tube second positioning flange is inserted into the tube arranged at the inner tube middle section to realize the positioning connection of the inner tube front section and the inner tube middle section, an inner tube second V-shaped annular groove is formed between the inner tube third conical surface and the inner tube fourth conical surface, and the inner tube second V-shaped annular groove is welded or a binder is applied to realize the fixed connection of the inner tube front section and the inner tube middle section.

Optionally, the outer wall of the inner tube front section is processed with an inner tube external connection thread at the position close to the front end, the inner tube external connection thread is matched with the outer tube internal connection thread, so that the connection between the outer tube front section and the inner tube front section is realized, and the outer wall of the inner tube front section is provided with a fourth sealing groove used for installing a sealing ring in the middle.

Preferably, the external diameter of the first step of inner tube tail section is less than the internal diameter at outer tube tail section middle part, and the external diameter of the first step of inner tube tail section is greater than the internal diameter of the anterior first locating hole of outer tube tail section and is less than the diameter of the cylinder at the central axis place of a plurality of through-hole of the anterior outer passageway of outer tube tail section, and the external diameter of the second step of inner tube tail section, the external diameter of inner tube middle section and the external diameter of inner tube anterior segment all slightly are less than the internal diameter of the anterior first locating hole of outer tube tail section.

Alternatively, the joints of the outer tube tail section and the outer tube middle section, the joints of the outer tube middle section and the outer tube front section, the joints of the inner tube tail section and the inner tube middle section, and the joints of the inner tube middle section and the inner tube front section are respectively connected through thread fit.

Preferably, the inner diameter of the inner pipe is set to be 15-20 mm, and the outer diameter of the outer pipe is set to be 60-65 mm; the wall thickness of the outer pipe is set to be 10-15 mm, such as 12 mm; the wall thickness of the inner tube is set to 1.5 to 3 mm, for example, 2 mm.

Alternatively, the inner tube is made of a seamless tube.

Optionally, pack into the afterbody with the inner tube from the outer tube, the inner tube is at the afterbody with the dismouting of sleeve pipe spanner, if meet the inner tube and be stained with the outer tube when being in the same place during the dismantlement, can do the spiral shell and detain the frock, pull out the inner tube by force.

Generally, after the inner tube and the outer tube are installed, the distance between the tail end of the inner tube and the tail end of the outer tube is about 50-100 mm, such as about 85 mm.

The invention has the beneficial effects that: (1) the length of the drill rods can be controlled, the drill rods are connected through internal and external threads when connected, the connection strength of the drill rods is guaranteed, and the concentric positioning sleeve and the concentric positioning shaft are matched for use, so that the concentric coaxiality of the drill rods is guaranteed; (2) the inner pipe and the outer pipe are connected through the screw threads, so that the connection strength is guaranteed, the airtightness between the inner pipe and the outer pipe is realized, and meanwhile, the relative position of the outer pipe and the inner pipe is fixed; (3) the sealing ring can effectively isolate the inner channel from the outer channel, so that the inner channel and the outer channel are separated to form a double-layer grouting channel; (4) the size of the inner pipe can be set to be 15-20 mm, the outer diameter of the outer pipe can be set to be 60-65 mm, the drift diameters of the inner channel and the outer channel are effectively enlarged, and the working efficiency of grouting is improved; (5) the inner pipe and the outer pipe are designed in a three-section mode respectively, and the lengths of the middle sections of the inner pipe and the outer pipe can be freely cut, so that the whole length of the double-layer grouting drill rod can be freely cut according to requirements, and the use flexibility is improved; (6) the middle sections of the inner pipe and the outer pipe can directly adopt standard seamless steel pipes, and only the front section and the tail section of the inner pipe and the outer pipe need to be specially manufactured, so that the manufacturing cost and the use cost are reduced.

Drawings

Fig. 1 shows a schematic structural view of a double-layer grouting drill pipe of the invention.

Fig. 2 shows a schematic structural view of the outer tube of the present invention.

Fig. 3 shows a schematic structural view of the inner tube of the present invention.

Fig. 4 shows a schematic structural view of the tail section of the outer tube of the present invention.

FIG. 5 shows a schematic structural view of the inner pipe end section of the present invention.

Fig. 6 shows a schematic of the construction of the middle section of the outer tube of the present invention.

Figure 7 shows a schematic of the construction of the mid-section of the inner tube of the present invention.

Figure 8 shows a schematic of the structure of the front section of the outer tube of the present invention.

Figure 9 shows a schematic of the construction of the inner tube front section of the present invention.

Fig. 10 shows a combined structure schematic diagram of the double-layer grouting drill pipe of the invention.

Detailed Description

The double-layer grouted drill pipe of the present invention will be described in detail with reference to the accompanying drawings.

As a non-limiting embodiment, as shown in fig. 1, the double-layer grouting drill rod of the present invention includes an outer pipe 1 and an inner pipe 2, the inner pipe 2 is inserted into the outer pipe 1 and is coaxial therewith, the inner pipe 2 is in threaded connection with the outer pipe 1, a central through hole of the inner pipe 2 is an inner channel 20, a gap between an inner wall of the outer pipe 1 and an outer wall of the inner pipe 2 is an outer channel 10, a tail section of the outer pipe 1 is provided with a connection internal thread 11 and a concentric positioning sleeve 13, and a front section of the outer pipe 1 is provided with a connection external thread 12 matched with the connection internal thread 11 and a concentric positioning shaft 14 matched with the concentric positioning sleeve 13, so that when a plurality of double-layer grouting drill rods are connected, connection is achieved through the connection internal thread 11 and the connection external thread 12, and concentricity is achieved through the concentric positioning sleeve 13 and the concentric positioning shaft 14. Wherein, outer passageway 10 is including the tail section, middle section and the anterior segment that communicate in proper order.

As shown in fig. 2, the outer tube 1 includes an outer tube tail section 1A, an outer tube middle section 1B, and an outer tube front section 1C, which are connected in sequence. As shown in fig. 3, the inner tube 2 includes an inner tube end section 2A, an inner tube middle section 2B, and an inner tube front section 2C, which are connected in sequence.

In this non-limiting embodiment, as shown in fig. 4, the inside of the outer tube tail section 1A is a step through hole, which includes an outer tube tail section tail portion 1A-1, an outer tube tail section middle portion 1A-2 and an outer tube tail section front portion 1A-3 from back to front, and the inside diameters of the outer tube tail section tail portion 1A-1, the outer tube tail section middle portion 1A-2 and the outer tube tail section front portion 1A-3 are sequentially reduced. The inner wall of the tail section tail part 1A-1 of the outer tube is processed with a connecting internal thread 11, the inner wall of the middle part 1A-2 of the tail section of the outer tube is processed into a concentric positioning sleeve 13, the front end of the front part 1A-3 of the tail section of the outer tube is provided with an outer tube first positioning flange 101 and an outer tube first conical surface 102, the inner wall of the front part 1A-3 of the tail section of the outer tube is processed into a first positioning hole 15, and a plurality of first through holes are drilled between the inner wall and the outer wall of the front part 1A-3 of the tail section of the outer tube in a direction parallel to the central axis of the outer tube, so that the tail section of the outer channel 10 is formed. In the non-limiting embodiment, the pipe can comprise 6-12 through holes, such as 8 through holes, which are distributed at equal intervals along the circumferential direction of the pipe.

As shown in fig. 6, the tail end of the outer tube middle section 1B is provided with an outer tube second conical surface 103, the inner peripheral wall of the outer tube middle section 1B is matched with the outer tube first positioning flange 101 of the outer tube tail section 1A, therefore, the outer tube first positioning flange 101 of the outer tube tail section 1A is inserted into the outer tube middle section 1B, the outer tube middle section 1B and the outer tube tail section 1A are positioned and connected, after connection, a first outer tube V-shaped ring groove is formed between the outer tube first conical surface 102 and the outer tube second conical surface 103, and the outer tube middle section 1B and the outer tube tail section 1A are fixedly connected into a whole by welding the outer tube first V-shaped ring groove or applying a binder. Similarly, the front end of the outer tube middle section 1B is provided with an outer tube third conical surface 104 for fixedly connecting the outer tube middle section 1B with the outer tube front section 1C. The annular gap between the inner peripheral wall of the outer tube middle section 1B and the outer peripheral wall of the inner tube middle section 2B forms the middle section of the outer channel 10.

As shown in fig. 8, the tail end of the outer tube front section 1C is provided with an outer tube second positioning flange 105 and an outer tube fourth conical surface 106, the outer tube second positioning flange 105 is matched with the inner peripheral wall of the outer tube middle section 1B, therefore, the outer tube second positioning flange 105 is inserted into the tube of the outer tube middle section 1B, the outer tube front section 1C and the outer tube middle section 1B are positioned and connected, after connection, an outer tube second V-shaped ring groove is formed between the outer tube third conical surface 104 and the outer tube fourth conical surface 106, and the outer tube front section 1C and the outer tube middle section 1B are fixedly connected into a whole by welding the outer tube second V-shaped ring groove or applying an adhesive.

The inner part of the outer tube front section 1C is provided with a step through hole, the outer tube front section comprises an outer tube front section tail part 1C-1, an outer tube front section middle part 1C-2 and an outer tube front section front part 1C-3 from back to front, and the inner diameters of the outer tube front section tail part 1C-1, the outer tube front section middle part 1C-2 and the outer tube front section front part 1C-3 are reduced in sequence. A plurality of second through holes are drilled between the inner wall and the outer wall of the outer tube front section 1C in a direction parallel to the central axis of the outer tube, so that a front section of the outer channel 10 is formed. In the non-limiting embodiment, the pipe can comprise 6-12 through holes, such as 8 through holes, which are distributed at equal intervals along the circumferential direction of the pipe. The inner wall of the middle part 1C-2 of the front section of the outer pipe is provided with outer pipe inner connecting threads 18 for connecting and fixing the inner pipe 2 in a threaded manner. In this non-limiting embodiment, the outer tube front section tail 1C-1 is made flared to facilitate insertion of the front end of the inner tube 2 into the outer tube front section tail 1C-1 during installation.

In the non-limiting embodiment, the outer portion of the outer tube front section 1C is substantially in a four-step shape with gradually reduced outer diameter, the first step S1 corresponds to the tail portion 1C-1 of the outer tube front section and the middle portion 1C-2 of the outer tube front section, the front end surface of the first step S1 is provided with a first sealing groove F1 for mounting a sealing ring, the connecting external thread 12 is arranged at the outer wall of the second step S2, the concentric positioning shaft 14 is arranged at the third step S3, the fourth step S4 forms an inner tube positioning flange, and the outer wall of the front end of the inner tube positioning flange is provided with a second sealing groove F2 for mounting the sealing ring.

As shown in figure 5, the inner part of the tail section 2A of the inner tube is also provided with a step through hole, the inner part from back to front comprises an inner tube tail section tail part 2A-1, an inner tube tail section middle part 2A-2 and an inner tube tail section front part 2A-3, the inner diameters of the inner tube tail section tail part 2A-1, the inner tube tail section middle part 2A-2 and the inner tube tail section front part 2A-3 are sequentially reduced, a dismounting thread 16 is processed on the inner wall of the inner tube tail section middle part 2A-2, and the dismounting thread 16 is used when the inner tube is dismounted. In this non-limiting embodiment, the inner bore of the inner tube end section tail 2A-1 is cylindrical.

The outer part of the inner pipe tail section 2A is approximately in a three-step shape with gradually reduced outer diameter, a first step T1 surrounds the periphery of the whole inner pipe tail section 2A-1 and the periphery of about half of the inner pipe tail section middle part 2A-2, a second step T2 surrounds the periphery of the other half of the inner pipe tail section middle part 2A-2 and the periphery of most of the inner pipe tail section front part 2A-3, and a third step T3 surrounds the periphery of the rest inner pipe tail section front part 2A-3. The front end face of the first step T1 forms a clamping table 17, and when the inner tube 2 is installed in the outer tube 1, the clamping table 17 abuts against the rear end face of the front part 1A-3 of the tail section of the outer tube to limit the inner tube 2 relative to the outer tube 1. The outer wall of the second step T2 is provided with a sealing groove F3 for mounting a sealing ring. The third step T3 forms an inner tube first locating flange 201 and an inner tube first conical surface 202. In this non-limiting embodiment, the outer portion of the first step T1 may be provided with a square or hexagonal shape for rotatably mounting the inner tube 2 using a socket wrench.

As shown in fig. 7, the tail end of the inner tube middle section 2B is provided with an inner tube second conical surface 203, the inner peripheral wall of the inner tube middle section 2B is matched with the inner tube first positioning flange 201 of the inner tube tail section 2A, therefore, the inner tube first positioning flange 201 of the inner tube tail section 2A is inserted into the inner tube of the inner tube middle section 2B, the inner tube middle section 2B and the inner tube tail section 2A are positioned and connected, after connection, an inner tube first V-shaped annular groove is formed between the inner tube first conical surface 202 and the inner tube second conical surface 203, and the inner tube middle section 2B and the inner tube tail section 2A are fixedly connected into a whole by welding or applying an adhesive to the inner tube first V-shaped annular groove. Similarly, the front end of the inner tube middle section 2B is provided with an inner tube third conical surface 204 for fixedly connecting the inner tube middle section 2B with the inner tube front section 2C.

As shown in fig. 9, the tail end of the inner tube front section 2C is provided with an inner tube second positioning flange 205 and an inner tube fourth conical surface 206, the inner tube second positioning flange 205 is matched with the inner peripheral wall of the inner tube middle section 2B, so that the inner tube second positioning flange 205 is inserted into the inner tube of the inner tube middle section 2B to realize the positioning connection of the inner tube front section 2C and the inner tube middle section 2B, after the connection, an inner tube second V-shaped ring groove is formed between the inner tube third conical surface 204 and the inner tube fourth conical surface 206, and the inner tube front section 2C and the inner tube middle section 2B are fixedly connected into a whole by welding or applying an adhesive to the inner tube second V-shaped ring groove.

The outer wall of inner tube anterior segment 2C has inner tube external connection screw thread 19 in the processing of neighbouring front end department, and inner tube external connection screw thread 19 and outer tube in-connection screw thread 18 phase-match realize being connected of outer tube anterior segment 1C and inner tube anterior segment 2C through threaded connection, and then realize that inner tube 2 is fixed with being connected of outer tube 1. The outer wall of the inner pipe front section 2C is provided with a sealing groove F4 used for installing a sealing ring in the middle.

Thus, the outer tube end section 1A, the outer tube middle section 1B, and the outer tube front section 1C are connected in this order and then fixed by welding or bonding to form one outer tube 1. An inner tube 2 is formed by connecting the inner tube tail section 2A, the inner tube middle section 2B and the inner tube front section 2C in sequence and then fixing the same by welding or bonding. And then the inner tube 2 is loaded from the tail end of the tail section 1A of the outer tube 1, the front section 2C of the inner tube 2 sequentially passes through the tail section 1A of the outer tube, the middle section 1B of the outer tube and the tail section 1C-1 of the front section 1C of the outer tube, and finally the outer connecting thread 19 of the inner tube front section 2C is fixedly connected with the inner connecting thread 18 of the middle section 1C-2 of the outer tube front section of the outer tube 1 through the rotation of the inner tube 2, so that the inner tube 2 is fixed in the outer tube 1. After installation, the clamping table 17 of the inner tube tail section 2A is abutted against the rear end face of the outer tube tail section front part 1A-3 to realize the limit of the inner tube 2 relative to the outer tube 1, and the sealing isolation between the inner channel 20 and the outer channel 10 is realized through the sealing fit of the sealing ring installed in the sealing groove F3 at the inner tube tail section 2A and the inner peripheral wall of the first positioning hole 15 at the outer tube tail section front part 1A-3 and the sealing fit of the sealing ring installed in the sealing groove F4 at the inner tube front section 2C and the inner peripheral wall of the outer tube front section tail part 1C-1.

Referring to fig. 10, an inner pipe 2 is installed inside an outer pipe 1 to obtain a double-layer grouting drill rod, and during grouting, a plurality of double-layer grouting drill rods are sequentially connected in a rotating manner through threads according to needs. An inner pipe positioning flange at a fourth step S4 of the front section 1C of the outer pipe of one double-layer grouting drill rod is inserted into the tail part 2A-1 of the inner pipe tail section 2A inside the other double-layer grouting drill rod, and is sealed with the inner hole peripheral wall of the tail part 2A-1 of the inner pipe tail section through a sealing ring arranged in a second sealing groove F2, so that the inner channel 20 and the outer channel 10 are sealed and isolated; a concentric positioning shaft 14 at a third step S3 of the front section 1C of the outer pipe of one double-layer grouting drill rod is arranged in a concentric positioning sleeve 13 at the middle part 1A-2 of the tail section of the outer pipe of the tail section 1A of the outer pipe of the other double-layer grouting drill rod so as to realize the concentric coaxiality of the two double-layer grouting drill rods; the connecting external thread 12 at the second step S2 of the front section 1C of the outer pipe of one double-layer grouting drill rod is fixed to the connecting internal thread 11 of the tail section 1A-1 of the outer pipe of the tail section 1A of the outer pipe of the other double-layer grouting drill rod in a threaded manner, so that the threaded fixed connection between the one double-layer grouting drill rod and the other double-layer grouting drill rod is realized; through a sealing ring arranged in a first sealing groove F1 at the first step S1 of the front section 1C of the outer pipe of one double-layer grouting drill rod, the sealing ring is in sealing fit with the tail end face of the tail section 1A of the outer pipe of the other double-layer grouting drill rod, so that the sealing isolation between the inner channel 20 and the outer channel 10 of two adjacent double-layer grouting drill rods and the sealing isolation between the outer channel 10 and the outer part of the grouting drill rod are realized.

In this non-limiting embodiment, as shown in fig. 2 to 5, the maximum outer diameter of the first step T1 of the inner tube tail section 2A is smaller than the inner diameter of the middle portion 1A-2 of the outer tube tail section, and the maximum outer diameter of the first step T1 of the inner tube tail section 2A is larger than the inner diameter of the first positioning hole 15 of the front portion 1A-3 of the outer tube tail section and smaller than the diameter of the cylindrical surface on which the central axes of the plurality of through holes of the outer channel 10 of the front portion 1A-3 of the outer tube tail section are located, so that the locking platform 17 of the inner tube tail section 2A can abut against the rear end surface of the front portion 1A-3 of the outer tube tail section to limit the inner tube 2 relative to the outer tube 1, and the flow of the grouting liquid in the outer channel 10 is not affected. In addition, the outer diameter of the second step T2 of the inner tube tail section 2A, the outer diameter of the inner tube middle section 2B and the outer diameter of the inner tube front section 2C are slightly smaller than the inner diameter of the first positioning hole 15 of the outer tube tail section front portion 1A-3, so that the inner tube 2 can be smoothly inserted into and fixed inside the outer tube 1.

In order to realize connection, as shown in fig. 1 and 10, when the connection is carried out, the inner pipe 2 is installed from the tail part of the outer pipe 1, the inner pipe 2 is disassembled and assembled by a sleeve spanner at the tail part, and when the inner pipe and the outer pipe are adhered together during disassembly, a screw fastener tool can be used to forcibly pull out the inner pipe 2.

Therefore, the double-layer grouting drill rod is formed by assembling the outer pipe and the inner pipe, the tail part of the outer pipe is provided with the internal thread and the concentric positioning sleeve, the front part of the outer pipe is provided with the external thread and the concentric positioning shaft, and the internal thread and the external thread are connected when a plurality of drill rods are connected, so that the connection strength and the concentric coaxiality of the plurality of drill rods are ensured. The inner pipe is made of a seamless pipe, the inner pipe is arranged from the tail part of the outer pipe and is in threaded connection with the outer pipe, the inner channel and the outer channel are isolated, and the double-slurry channel is formed. The setting of sealing washer not only can let interior passageway and outer passageway keep apart, forms two thick liquid passageways, can also prevent that two drilling rods installation back thick liquid in the outer passageway from outflowing.

Although preferred embodiments of the present invention have been described in detail herein, it is to be understood that this invention is not limited to the precise construction and steps herein shown and described, and that other modifications and variations may be effected by one skilled in the art without departing from the spirit and scope of the invention.

Claims (10)

1. A double-layer grouted drill pipe, comprising: the outer pipe and insert locate in the outer pipe rather than the inner tube of coaxial center, the inner tube with threaded connection between the outer pipe, the middle part through-hole of inner tube is interior passageway, the inner wall of outer pipe with the clearance between the outer wall of inner tube is outer passageway, the back end of outer pipe is equipped with connects internal thread and concentric position sleeve, the anterior segment of outer pipe be equipped with connect internal thread assorted connect the external screw thread and with concentric position sleeve assorted concentric position axle to when a plurality of double-deck slip casting drilling rod is connected, through connect the internal thread with connect the external screw thread and realize concentric axiality, and through concentric position sleeve reaches concentric position axle.

2. The double-layer grouting drill pipe as claimed in claim 1, wherein the outer pipe comprises an outer pipe tail section, an outer pipe middle section and an outer pipe front section which are connected in sequence, the inner pipe comprises an inner pipe tail section, an inner pipe middle section and an inner pipe front section which are connected in sequence, and the inner pipe front section is in threaded connection with the outer pipe front section.

3. The double-layer grouting drill rod as claimed in claim 2, wherein the outer tube tail section is internally provided with a step through hole and comprises an outer tube tail section tail part, an outer tube tail section middle part and an outer tube tail section front part, the inner diameter of the outer tube tail section tail part is gradually reduced from back to front, the connecting internal thread is machined on the inner wall of the outer tube tail section tail part, the concentric locating sleeve is arranged on the inner wall of the outer tube tail section middle part, the outer tube first locating flange is arranged at the front end of the outer tube tail section front part, the first locating hole is machined on the inner wall of the outer tube tail section front part, and a plurality of first through holes are arranged between the inner wall of the outer tube tail section front part and the outer wall in a direction parallel to the central axis of the outer tube to form the tail section of the outer channel.

4. The double-layer grouting drill rod as claimed in claim 3, wherein the inner peripheral wall of the middle section of the outer pipe is matched with the first positioning flange of the outer pipe of the tail section of the outer pipe, the first positioning flange of the outer pipe is inserted into the pipe of the middle section of the outer pipe so as to realize the positioning connection of the middle section of the outer pipe and the tail section of the outer pipe, an annular gap between the inner peripheral wall of the middle section of the outer pipe and the outer peripheral wall of the middle section of the inner pipe forms the middle section of the outer channel, and the middle section of the outer channel is communicated with the tail section of the outer channel.

5. The double-layer grouting drill rod as claimed in claim 4, wherein the tail end of the outer tube front section is provided with an outer tube second positioning flange, the outer tube second positioning flange is matched with the inner peripheral wall of the outer tube middle section, and the outer tube second positioning flange is inserted into the tube of the outer tube middle section so as to realize the positioning connection of the outer tube front section and the outer tube middle section.

6. The double-layer grouting drill rod as claimed in claim 5, wherein the inner part of the front section of the outer pipe is a step through hole, the step through hole comprises a tail part of the front section of the outer pipe, a middle part of the front section of the outer pipe and a front part of the front section of the outer pipe, the inner diameter of the tail part of the front section of the outer pipe, the inner diameter of the middle part of the front section of the outer pipe and the inner diameter of the front section of the outer pipe are sequentially reduced from back to front, a plurality of second through holes are arranged between the inner wall and the outer wall of the front section of the outer pipe in a direction parallel to the central axis of the outer pipe to form the front section of the outer channel, and the front section of the outer channel is communicated with the middle section of the outer channel; and the inner wall of the middle part of the front section of the outer pipe is provided with an outer pipe internal connecting thread for fixing the inner pipe in a threaded connection manner.

7. The double-layer grouting drill rod as claimed in claim 6, wherein the outer part of the front section of the outer pipe is in a four-step shape with gradually reduced outer diameter, the first step corresponds to the tail part of the front section of the outer pipe and the middle part of the front section of the outer pipe, a first sealing groove for installing a sealing ring is arranged on the front end face of the first step, the connecting external thread is arranged on the outer wall of the second step, the concentric positioning shaft is arranged on the third step, the fourth step forms an inner pipe positioning flange, and a second sealing groove for installing a sealing ring is arranged on the outer wall of the front end of the inner pipe positioning flange.

8. The double-layer grouting drill rod as claimed in claim 3, wherein the inner part of the inner pipe tail section is a step through hole and comprises an inner pipe tail section tail part, an inner pipe tail section middle part and an inner pipe tail section front part with sequentially reduced inner diameters from back to front, wherein the inner wall of the inner pipe tail section middle part is provided with a dismounting thread;

the outside of inner tube tail section is the three-step form that the external diameter reduces gradually, the preceding terminal surface of first step forms the ka tai, be used for with the inner tube install in when the outer tube is intraductal, the ka tai support lean on in the anterior rear end face of outer tube tail section realizes the inner tube for the spacing of outer tube, the outer wall of second step is equipped with the third seal groove that is used for installing the sealing washer, third step department is formed with the first locating flange of inner tube.

9. The double-layer grouting drill pipe as claimed in claim 8, wherein the inner peripheral wall of the inner pipe middle section is matched with the inner pipe first positioning flange of the inner pipe tail section, and the inner pipe first positioning flange of the inner pipe tail section is inserted into the inner pipe of the inner pipe middle section so as to realize the positioning connection of the inner pipe middle section and the inner pipe tail section.

10. The double-layer grouting drill pipe as claimed in claim 9, wherein the tail end of the inner pipe front section is provided with an inner pipe second positioning flange, the inner pipe second positioning flange is matched with the inner peripheral wall of the inner pipe middle section, and the inner pipe second positioning flange is inserted into the pipe of the inner pipe middle section so as to realize the positioning connection of the inner pipe front section and the inner pipe middle section;

the outer wall of the inner pipe front section is processed with an inner pipe outer connecting thread at the position close to the front end, the inner pipe outer connecting thread is matched with the outer pipe inner connecting thread so as to realize the connection of the outer pipe front section and the inner pipe front section, and the outer wall of the inner pipe front section is provided with a fourth sealing groove used for installing a sealing ring in the middle.

Images