Closed PDC (Polycrystalline Diamond Compact) coring bit with improved water hole structure

Abstract

The utility model discloses a closed PDC (Polycrystalline Diamond Compact) coring bit with an improved water hole structure. The closed PDC coring bit comprises a bit body and a bit joint, a plurality of water hole flow channels are arranged on a steel core of the drill bit body at intervals in the circumferential direction, an anti-erosion lantern ring is arranged on the inlet end face of each water hole flow channel, a hole opening of each anti-erosion lantern ring corresponds to a hole opening of the corresponding water hole flow channel, an alloy sleeve is arranged in each water hole flow channel, one end of each alloy sleeve extends to the inlet end of the corresponding water hole flow channel, and the other end of each alloy sleeve extends to the outlet end of the corresponding water hole flow channel. And the anti-erosion lantern ring, the alloy sleeve and the water hole flow channel are sealed and fixed. The erosion-resistant PDC coring bit has the advantages that the erosion-resistant performance is better, and the service life of the closed PDC coring bit is prolonged.

Description

TECHNICAL FIELD

[0001] The utility model relates to stratum drilling exploitation PDC drill bit technical field, more specifically, the utility model relates to a kind of closed PDC coring drill bit with improved water hole structure. BACKGROUND

[0002] PDC composite sheet drill bit is widely used in coalfield drilling, geological exploration, oil drilling operation. There are generally conventional drilling and coring drilling in drilling operation. When the formation information needs to be analyzed in detail and relevant information is obtained, coring operation is needed for formation core.

[0003] The current coring has the way of grabbing and the way of collecting, according to the obtaining method and requirement of core, in order to better core obtaining rate, and the core is not polluted by drilling fluid, the current closed coring drill bit is generally used for coring operation.

[0004] Closed coring is to isolate the closed liquid and the drilling fluid in the center of the drill bit, the core drilled can be well prevented from being polluted by drilling fluid, not only the core is efficiently and completely obtained, but also the cleanliness of the core is ensured, and the accuracy of subsequent formation analysis data is ensured. Due to the mutual restriction of drilling coring tool and well size, the space position of the inlet of drilling fluid of the closed coring PDC drill bit is very small, the side wall of the inlet of liquid flow channel is very thin, and the drilling fluid vortex is easily formed due to the change of flow field, the side wall is easily perforated by the drilling fluid vortex, and the drill bit is scrapped in advance. To solve this technical problem, we design a closed coring drill bit with water hole structure orifice using metal printing technology according to actual use requirement. SUMMARY

[0005] The utility model discloses a kind of closed PDC coring drill bits with improved water hole structure, with the advantages that erosion resistance is better, and the service life of closed PDC coring drill bit is extended.

[0006] The technical scheme that the utility model solves this technical problem is as follows: a kind of closed PDC coring drill bit with improved water hole structure, comprising: drill bit body and drill bit connector;A plurality of water hole flow channels are arranged on the steel core of drill bit body in circumferential direction interval, the inlet end surface of water hole flow channel is provided with anti-erosion sleeve ring, the anti-erosion sleeve ring is provided with opening hole corresponding to water hole flow channel, the opening hole of anti-erosion sleeve ring is corresponding with the opening hole of water hole flow channel, alloy sleeve pipe is arranged in water hole flow channel, one end of alloy sleeve pipe extends to the inlet end of water hole flow channel, and anti-erosion sleeve ring, alloy sleeve pipe and water hole flow channel are sealed and fixed.

[0007] As a further scheme of the utility model, the opening hole of anti-erosion sleeve ring is tapered structure with inlet aperture larger than outlet aperture;The alloy sleeve pipe is tapered structure with inlet aperture larger than outlet aperture.

[0008] As a further scheme of the utility model is: the opening of the anti-erosion sleeve ring and the radial section of the alloy sleeve are oval.

[0009] As a further scheme of the utility model is: the water hole flow channel is of a taper structure, the water hole flow channel entrance is of an oval section, the long axis is 2D, the short axis is D, and the water hole flow channel exit is of a circular section, the diameter is 0.8D.

[0010] As a further scheme of the utility model is: the crown of the drill bit body is circumferentially provided with a blade, and the blade is welded with a PDC tooth.

[0011] As a further scheme of the utility model is: the number of the water hole flow channels is the same as that of the blades.

[0012] As a further scheme of the utility model is: after the assembled drill bit body is connected with the drill bit joint, the drill bit body and the drill bit joint are welded into an integral whole through a weld.

[0013] As a further scheme of the utility model is: the anti-erosion sleeve ring is a metal printed anti-erosion sleeve ring.

[0014] The utility model at least has the following beneficial effects:

[0015] The metal printed anti-erosion sleeve ring effectively controls the manufacturing cost and solves the problems of small orifice position and insufficient anti-erosion life. In addition, the anti-erosion sleeve ring is easier to install at the water hole flow channel entrance, reducing the manufacturing difficulty.

[0016] The water hole flow channel entrance and exit are designed as oval, and the overall water hole flow channel is designed as a taper structure, which can better avoid the water hole flow channel entrance vortex problem and improve the service life of the sealed PDC core drilling bit.

[0017] The alloy sleeve in the water hole flow channel can better cooperate with the metal printed anti-erosion sleeve ring to form effective protection.

[0018] Other advantages, objects and features of the utility model will be partly embodied through the following description, and will be partly understood by the person skilled in the art through the research and practice of the utility model. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a structure schematic view of a sealed PDC core drilling bit with improved water hole structure of an embodiment of the utility model;

[0020] Figure 2 is a structure schematic view of an anti-erosion sleeve ring of the utility model;

[0021] Figure 3 is a water hole flow channel and drill bit body crown wing setting schematic diagram of an embodiment of the utility model.

[0022] Wherein, 1-drill bit joint, 2-drill bit body, 3-erosion-resistant sleeve ring, 4-alloy sleeve, 5-weld, 6-water hole flow channel, 7-blade, 8-PDC tooth, 9-opening. DETAILED DESCRIPTION

[0023] The utility model will be described in detail and completely below in conjunction with the drawings. Those skilled in the art will be able to realize the utility model based on these descriptions. Before the utility model is described in conjunction with the drawings, it needs to be pointed out specially: the technical solutions and technical features provided in each part including the following description in the utility model can be combined with each other in the case of no conflict.

[0024] In addition, the embodiments of the utility model involved in the following description are usually only a part of the embodiments of the utility model, not all the embodiments. Therefore, all other embodiments obtained by those skilled in the art based on the embodiments in the utility model without making creative efforts should belong to the protection scope of the utility model.

[0025] The utility model will be described in detail and completely below in conjunction with the drawings. Those skilled in the art will be able to realize the utility model based on these descriptions. Before the utility model is described in conjunction with the drawings, it needs to be pointed out specially: the technical solutions and technical features provided in each part including the following description in the utility model can be combined with each other in the case of no conflict.

[0026] As shown in Figure 1 , 2 The utility model provides a sealed PDC coring drill bit of water hole structure improvement, including: drill bit body 2 and drill bit joint 1, in prior art, drill bit body 2 includes steel core, a plurality of water hole flow channels 6 are arranged on the steel core of drill bit body 2 along the circumference interval, water hole flow channel 6 is used for transporting drilling fluid, the inlet end surface of water hole flow channel 6 is provided with erosion-resistant sleeve ring 3, the opening 9 of erosion-resistant sleeve ring 3 is provided with at water hole flow channel 6, the orifice of erosion-resistant sleeve ring 3 opening corresponds with the orifice of water hole flow channel 6, alloy sleeve 4 is arranged in water hole flow channel 6, in this embodiment, alloy sleeve 4 is inlaid and is assembled in water hole flow channel 6, to form a whole, one end of alloy sleeve 4 extends to the inlet end of water hole flow channel 6, alloy sleeve 4 can be only arranged in the upper portion of water hole flow channel 6, can also extend to the whole water hole flow channel 6, and its length can be designed according to actual demand, alloy sleeve 4 is prepared with erosion-resistant hard alloy, to protect the thin wall of water hole flow channel 6.Erosion-resistant sleeve ring 3, alloy sleeve 4 and water hole flow channel 6 are sealed and fixed, after erosion-resistant sleeve ring 3, alloy sleeve 4 are assembled, erosion-resistant sleeve ring 3, alloy sleeve 4 and drill bit body 2 can be integrated by brazing, to avoid liquid flow.

[0027] AsFigure 1 As shown in the figure, the water hole flow passage 6 is machined on the drill bit body 2, the alloy sleeve 4 is assembled into the water hole flow passage 6, and the anti-erosion sleeve ring 3 is installed at the inlet end surface of the water hole flow passage 6 on the left side of the drill bit body 2. The anti-erosion sleeve ring 3 is limited by the drill bit body 2, the alloy sleeve 4 and the drill bit joint 1 to form a good positioning and fixing, and the assembled drill bit body 2 and the drill bit joint 1 are connected into one through the weld 5 to form the sealed coring drill bit.

[0028] The technical scheme can further include the following technical details to better achieve the technical effects: the opening of the anti-erosion sleeve ring 3 is a tapered structure with an inlet aperture larger than an outlet aperture; the alloy sleeve 4 is a tapered structure with an inlet aperture larger than an outlet aperture, thereby playing a role of liquid flow stabilization, and the outlet aperture of the anti-erosion sleeve ring 3 is equal to the inlet aperture of the alloy sleeve 4.

[0029] The technical scheme can further include the following technical details to better achieve the technical effects: the opening of the anti-erosion sleeve ring 3 and the radial section of the alloy sleeve 4 are both elliptical, which can better avoid the generation of vortex. The anti-erosion sleeve ring 3 can be matched or inlaid with the alloy sleeve 4 in a suitable size.

[0030] The technical scheme can further include the following technical details to better achieve the technical effects: the water hole flow passage 6 is a tapered structure, the inlet of the water hole flow passage 6 is an elliptical section with a major axis of 2D and a minor axis of D, and the outlet of the water hole flow passage 6 is a circular section with a diameter of 0.8D. Through the tapered design of the water hole flow passage 6 from an ellipse to a circle, the drilling fluid flow velocity gradient changes gently, the Reynolds number is reduced, and in addition, the design of the taper angle avoids the sudden change of the streamline, thereby improving the service life of the drill bit.

[0031] The technical scheme can further include the following technical details to better achieve the technical effects: the crown on the right side of the drill bit body 2 is circumferentially provided with a blade 7, and a plurality of PDC teeth 8 are welded on the blade 7 for rock cutting;

[0032] The technical scheme can further include the following technical details to better achieve the technical effects: as Figure 3 As shown in the figure, the number of the water hole flow passages 6 is the same as the number of the blades 7 in a conventional case. In a preferred embodiment, the number of the water hole flow passages 6 is greater than 3. However, it is not limited to being equal to the number of the blades 7 of the drill bit body 2, and according to the design needs, a plurality of water hole flow passages 6 can be arranged between every two blades 7 or no water hole flow passage 6 is arranged.

[0033] The technical scheme can further include the following technical details to better achieve the technical effects: after the assembled drill bit body 2 and the drill bit joint 1 are connected, the drill bit body 2 and the drill bit joint 1 are welded into one through the weld 5, the drill bit joint 1 is threadedly connected with the drill pipe, and thereby the torque and the drilling pressure are transmitted.

[0034] The technical scheme can further include the following technical details to better achieve the technical effects: the anti-erosion sleeve 3 is an anti-erosion sleeve 3 printed by metal, and it should be noted that in other embodiments, it is not limited to metal printing, and can also be other anti-erosion materials, such as ceramics, tungsten steel, etc. When specifically manufactured, an alloy anti-erosion sleeve 3, such as tungsten carbide alloy powder, or a ceramic ring with high anti-erosion performance, etc. is 3D printed at the water hole flow channel 6 orifice. The anti-erosion sleeve 3 is processed according to the actual size, and the anti-erosion sleeve 3 is printed with a flow channel hole.

[0035] Although the embodiments of the present application have been disclosed as above, they are not limited to the application and use listed in the specification and embodiments, and can be fully applied to various fields suitable for the present application. For those skilled in the art, other modifications can be easily realized, and therefore the present application is not limited to specific details and the embodiments shown and described herein.

Claims

1. An improved closed PDC coring bit with water hole structure, characterized in that, The application relates to a drill bit body and a drill bit joint. The water hole flow channel is provided with an anti-erosion sleeve ring at an inlet end, the anti-erosion sleeve ring is provided with an opening corresponding to the water hole flow channel, the opening of the anti-erosion sleeve ring corresponds to the opening of the water hole flow channel, the water hole flow channel is provided with an alloy sleeve, and one end of the alloy sleeve extends to the inlet end of the water hole flow channel to seal and fix the anti-erosion sleeve ring, the alloy sleeve and the water hole flow channel.

2. The improved closed PDC coring bit of claim 1, wherein, The opening of the anti-erosion sleeve ring is a tapered structure with an inlet diameter larger than an outlet diameter; and the alloy sleeve is a tapered structure with an inlet diameter larger than an outlet diameter.

3. The improved closed PDC coring bit of claim 2, wherein, The opening of the anti-erosion sleeve ring and the radial section of the alloy sleeve are both elliptical.

4. The improved closed PDC coring bit of claim 1, wherein, The water hole flow channel is a tapered structure, the inlet of the water hole flow channel is elliptical with a long axis of 2D and a short axis of D, and the outlet of the water hole flow channel is circular with a diameter of 0.8D.

5. The improved closed PDC coring bit of claim 1, wherein, The crown of the drill bit body is provided with a blade in a circumferential direction, and the blade is welded with a PDC tooth.

6. The improved closed PDC coring bit of claim 5 wherein, The number of the water hole flow channels is the same as that of the blades.

7. The improved closed PDC coring bit of claim 1 wherein, After the assembled drill bit body is connected with the drill bit joint, the drill bit body and the drill bit joint are welded into an integrated whole through a welding seam.

8. The improved closed PDC coring bit of claim 1 wherein, The anti-erosion sleeve ring is a metal printing anti-erosion sleeve ring.

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