High-efficiency energy-saving PDC drill bit

Abstract

The application provides a high-efficiency energy-saving PDC drill bit, and belongs to the technical field of drilling equipment. The high-efficiency energy-saving PDC drill bit comprises a base, a plurality of blades, a plurality of tooth bases, a plurality of first cutting teeth, a plurality of second cutting teeth and an oil hole. The plurality of tooth bases correspond to the plurality of blades one by one. The tooth bases are hingedly connected to one side of the corresponding blades, and a hydraulic cavity is formed between the tooth bases and the blades. The plurality of first cutting teeth are fixed on the plurality of tooth bases respectively. The plurality of second cutting teeth are fixed on the top of the plurality of blades respectively, and the hardness and structural strength of the second cutting teeth are greater than those of the first cutting teeth. The oil hole is arranged in the base and the blade, and the oil hole is communicated with the hydraulic cavity. The oil hole introduces hydraulic oil into the hydraulic cavity to make the tooth bases swing. The first cutting teeth swing to the inner side of the second cutting teeth by means of the tooth bases to make the second cutting teeth drill. The high-efficiency energy-saving PDC drill bit can switch different cutting teeth according to different use scenarios, improve the drilling efficiency and prolong the service life of the drill bit.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of drilling equipment, and more particularly relates to a high-efficiency energy-saving PDC drill bit. BACKGROUND

[0002] The PDC drill bit is a full name of a polycrystalline diamond compact drill bit, and the polycrystalline diamond compact drill bit is mainly used for a composite sheet drill bit for geological exploration and is suitable for soft to medium-hard rock layers. Some new composite sheets newly developed by some manufacturers can be applied to rock layers with a hardness of ten levels.

[0003] The PDC drill bit mainly breaks rocks in a scraping and cutting manner. Therefore, the PDC drill bit can effectively eat into the stratum and break rocks during drilling, which guarantees the high-efficiency drilling of the PDC drill bit. The present PDC drill bit for full drilling has all the blade wings as cutting wings. Therefore, when the drilling pressure is applied, the pressure is uniformly distributed on each cutting tooth of the PDC drill bit. The more the cutting wings of the PDC drill bit, the greater the density of the cutting teeth. Under the same drilling pressure, the pressure intensity distributed on the single cutting tooth is smaller, which leads to a shallower depth of the PDC drill bit eating into the stratum. Especially when the strong plastic stratum is drilled, the stratum rock cannot be effectively broken, which causes a serious "stick-slip" effect and a great decrease in the rate of penetration. If the drilling pressure is blindly increased, the number of the drill bits will be affected. More importantly, when the hardness of the stratum increases, more time is needed for drilling, which leads to a low efficiency and a short service life of the drill bit. SUMMARY

[0004] The application aims to provide a high-efficiency energy-saving PDC drill bit, and aims to solve the problems of a low drilling efficiency and a short service life of the drill bit when the hardness of the stratum increases.

[0005] To achieve the above-mentioned purpose, the technical scheme adopted by the application is as follows: a high-efficiency energy-saving PDC drill bit is provided, which comprises:

[0006] a base;

[0007] a plurality of blade wings, the plurality of blade wings are arranged along the circumference of the base and are fixed on the top of the base;

[0008] a plurality of tooth bases, the plurality of tooth bases correspond to the plurality of blade wings one by one; the tooth base is hinged on one side of the corresponding blade wing, and a hydraulic cavity is formed between the tooth base and the blade wing;

[0009] a plurality of first cutting teeth, which are respectively fixed on the plurality of tooth bases;

[0010] a plurality of second cutting teeth, which are respectively fixed on the top of the plurality of blade wings, and the hardness and structural strength of the second cutting teeth are greater than those of the first cutting teeth;

[0011] An oil hole is formed in the base and the blade wing, and the oil hole is communicated with the hydraulic cavity, the oil hole drains hydraulic oil into the hydraulic cavity for swinging the tooth base, and the first cutting tooth swings to the inner side of the second cutting tooth by the tooth base for drilling the second cutting tooth.

[0012] In a possible implementation, a positioning groove is formed on the blade wing, and the tooth base abuts against and swings in the positioning groove.

[0013] In a possible implementation, a limiting plate is fixed on the tooth base, and the limiting plate extends to the blade wing from a side of the tooth base; the limiting plate is inserted into the blade wing and cooperates with the positioning groove to limit the swinging direction of the first cutting tooth.

[0014] In a possible implementation, a sealing pad is arranged between the blade wing and the tooth base, and the sealing pad, the blade wing, the tooth base and the limiting plate surround the hydraulic cavity to be sealed.

[0015] In a possible implementation, a positioning groove is formed on the outer side of the limiting plate, a limiting block is fixed on the blade wing, the limiting block extends into the positioning groove and cooperates with the positioning groove to slide; the limiting block prevents the limiting plate from sliding out of the blade wing through the positioning groove.

[0016] In a possible implementation, the limiting plate is integrally formed with the tooth base.

[0017] In a possible implementation, a barrier pad is arranged on the outer side of the limiting plate, and the barrier pad is arranged between the tooth base and the blade wing to prevent impurities from contacting the limiting plate.

[0018] In a possible implementation, one end of the oil hole is communicated with an oil pump, the oil pump injects hydraulic oil into the hydraulic cavity through the oil hole to swing the tooth base, and the oil pump reduces the pressure in the hydraulic cavity by sucking hydraulic oil to position the tooth base on the blade wing.

[0019] In a possible implementation, the number of oil holes is multiple, and the multiple oil holes are communicated with the oil pump, and the oil pump swings the corresponding multiple tooth bases by multiple oil holes.

[0020] In a possible implementation, three oil holes are communicated with the oil pump through a control valve.

[0021] The high-efficiency energy-saving PDC drill bit has the beneficial effects that, compared with the prior art, the plurality of blades are arranged along the circumference of the base, and the plurality of blades are fixed on the top of the base. The plurality of tooth bases are hinged on one side of the corresponding blade, and the hydraulic cavity is surrounded between the tooth base and the corresponding blade. The first cutting tooth is fixed on the tooth base, the second cutting tooth is fixed on the top of the blade, and the hardness and structural strength of the second cutting tooth are greater than those of the first cutting tooth. The oil hole is arranged in the base and the blade, and the oil hole is communicated with the hydraulic cavity.

[0022] In actual application, when drilling in a stratum with large hardness, the oil hole guides the hydraulic oil into the hydraulic cavity, and the volume of the hydraulic cavity is increased, so that the tooth base can swing a certain distance on the blade. Since the first cutting tooth is located on the inner side of the second cutting tooth after the tooth base swings a certain distance, the second cutting tooth is exposed to the first cutting tooth to drill, so that the PDC drill bit can switch different cutting teeth according to different use scenarios, improve the drilling efficiency, and prolong the service life of the drill bit. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0024] Figure 1 The structure schematic diagram of the high-efficiency energy-saving PDC drill bit provided for the first embodiment of the present application is shown in the figure.

[0025] Figure 2 The connection schematic diagram of the blade, the limiting plate and the tooth base provided for the second embodiment of the present application is shown in the figure.

[0026] In the figure: 1, base; 2, blade; 3, first cutting tooth; 4, second cutting tooth; 5, sealing gasket; 6, oil hole; 7, limiting block; 8, blocking pad; 9, limiting plate. DETAILED DESCRIPTION

[0027] In order to make the technical problems, technical solutions and beneficial effects of the present application more clearly understood, the following will further describe the present application in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0028] Please refer to Figure 1 and Figure 2The application provides a high-efficiency energy-saving PDC drill bit, and the PDC drill bit comprises a base 1, a plurality of blades 2, a plurality of tooth bases, a plurality of first cutting teeth 3, a plurality of second cutting teeth 4 and an oil hole 6. The plurality of blades 2 are arranged along the circumference of the base 1 and are all fixed on the top of the base 1. The plurality of tooth bases correspond to the plurality of blades 2 one by one; the tooth base is hinged on one side of the corresponding blade 2, and a hydraulic cavity is formed between the tooth base and the blade 2. The plurality of first cutting teeth 3 are respectively fixed on the plurality of tooth bases. The plurality of second cutting teeth 4 are respectively fixed on the top of the plurality of blades 2, and the hardness and structural strength of the second cutting teeth 4 are both greater than those of the first cutting teeth 3. The oil hole 6 is arranged in the base 1 and the blade 2, and the oil hole 6 is communicated with the hydraulic cavity, the oil hole 6 is used for draining hydraulic oil into the hydraulic cavity to make the tooth base swing, and the first cutting tooth 3 is swung to the inner side of the second cutting tooth 4 by the tooth base to make the second cutting tooth 4 drill.

[0029] The high-efficiency energy-saving PDC drill bit has the advantages that compared with the prior art, the plurality of blades 2 are arranged along the circumference of the base 1, and the plurality of blades 2 are all fixed on the top of the base 1. The plurality of tooth bases are hinged on one side of the corresponding blade 2, and a hydraulic cavity is formed between the tooth base and the corresponding blade 2. The first cutting tooth 3 is fixed on the tooth base, the second cutting tooth 4 is fixed on the top of the blade 2, and the hardness and structural strength of the second cutting tooth 4 are both greater than those of the first cutting tooth 3. The oil hole 6 is arranged in the base 1 and the blade 2, and the oil hole 6 is communicated with the hydraulic cavity.

[0030] In actual application, when drilling a stratum with high hardness, the oil hole 6 drains hydraulic oil into the hydraulic cavity, the volume of the hydraulic cavity is increased, so that the tooth base can swing on the blade 2 by a certain distance. Since the first cutting tooth 3 is located at the inner side of the second cutting tooth 4 after the tooth base swings by a certain distance, the second cutting tooth 4 is exposed to the first cutting tooth 3 to drill, so that the PDC drill bit can switch different cutting teeth according to different use scenarios, the drilling efficiency is improved, and the service life of the drill bit is prolonged.

[0031] The PDC drill bit is an important rock breaking tool in the field of drilling engineering, and is divided into rigid PDC drill bits and matrix PDC drill bits according to manufacturing methods, with the rapid development of manufacturing technology, the rigid PDC drill bit has high machining efficiency and high strength, and is applied more and more.

[0032] In the case of a hard stratum, a roller bit is generally not used, because the roller bit has slow mechanical drilling speed and short service life, and often causes additional operations, increases drilling time and operation cost. Therefore, for a hard stratum, a PDC drill bit with faster mechanical drilling speed is usually used to improve the drilling speed.

[0033] PDC drill bit uses artificial polycrystalline diamond compact as cutting element to break rock in a cutting way, has good rock breaking performance in medium-hard formation, high penetration rate and long service life, and remarkable comprehensive economic benefit. However, when drilling through soft and hard alternating formation, the performance of PDC drill bit is not ideal. Especially when drilling through some formation with less soft and hard interbed, the cutting teeth of PDC diamond drill bit are easily damaged by impact.

[0034] In the traditional sense, the blade wing 2, the base 1 and the tooth base are integrally formed, and the first cutting tooth 3 is directly welded and fixed on the tooth base. The above structure is the common processing method of PDC drill bit on the market. However, the problem of the above method is that the position and angle of the cutting tooth relative to the base 1 are fixed, and the force and direction of the cutting tooth on the rock formation are also relatively fixed, which leads to that when the hardness of the rock formation increases, it takes a long time to complete the drilling, and the service life of the whole drill bit is shortened.

[0035] In some embodiments of the high-efficiency energy-saving PDC drill bit provided in the application, please refer to Figure 2 A positioning groove is formed on the blade wing 2, and the tooth base abuts against and swings in the positioning groove. The tooth base and the blade wing 2 need to have strong connection strength, because the formation has a certain force on the first cutting tooth 3 during drilling, and the force is finally applied to the base 1 through the tooth base and the blade wing 2. In the present application, in order to enable the first cutting tooth 3 to change a certain angle relative to the blade wing 2, it is necessary to enable the tooth base to swing a certain angle within a certain range relative to a point, and the swinging distance and direction are controllable. In order to achieve the above technical effects, a positioning groove is formed on one side of the blade wing 2, the positioning groove is an arc-shaped groove, the bottom of the tooth base abuts against in the positioning groove, and in actual application, the bottom of the tooth base swings in the positioning groove with the bottom of the tooth base as the center, and the bottom of the tooth base is limited in the positioning groove to prevent the tooth base from coming out of the positioning groove.

[0036] In some embodiments of the high-efficiency energy-saving PDC drill bit provided in the application, please refer to Figure 2 A limiting plate 9 is fixed on the tooth base, and the side of the limiting plate 9 away from the tooth base extends into the blade wing 2; the limiting plate 9 and the blade wing 2 are inserted and matched with the positioning groove to limit the swinging direction of the first cutting tooth 3.

[0037] In order to facilitate installation, the positioning groove is an open slot, but if only one positioning groove is provided, the tightness of the hydraulic cavity cannot be guaranteed, and more importantly, the tooth base cannot be guaranteed to swing in a specific direction, and the tooth base has a very high probability of coming out of the positioning groove under the action of hydraulic oil.

[0038] In order to solve the above problems, a limiting plate 9 is fixed on the side of the tooth base close to the blade 2, one side of the limiting plate 9 is fixed on the tooth base, and the other side is a free end and extends into the blade 2. The limiting plate 9 has a certain structural strength, and because the limiting plate 9 is always in sliding fit with the blade 2, the limiting plate 9 and the tooth base are connected by the connection strength, and the positioning of the limiting plate 9 and the blade 2 is matched with the positioning groove, so that the tooth base can swing within a certain range around the contact point of the positioning groove under the action of hydraulic oil.

[0039] In some embodiments of the high-efficiency energy-saving PDC drill bit provided in the application, referring to Figure 2 , a positioning groove is formed on the outer side of the limiting plate 9, and a limiting block 7 is fixed on the blade 2 and extends into the positioning groove and is in sliding fit with the positioning groove; the limiting block 7 is used to prevent the limiting plate 9 from sliding out of the blade 2 through the positioning groove. The cross section of the limiting plate 9 in the region where the positioning groove is formed is small, and the cross section of the side of the limiting plate 9 away from the tooth base is large, so that the limiting of the limiting block 7 prevents the limiting plate 9 from completely separating from the blade 2, and the limiting block 7 can be fixed on the blade 2 after the limiting plate 9 is installed.

[0040] In some embodiments of the high-efficiency energy-saving PDC drill bit provided in the application, referring to Figure 2 , a sealing pad 5 is arranged between the blade 2 and the tooth base, and the sealing pad 5, the blade 2, the tooth base and the limiting plate 9 form a sealed hydraulic chamber.

[0041] If only the tooth base is placed in the positioning groove, the tooth base can always abut against the positioning groove by the connection strength of the limiting plate 9 and the blade 2 and the connection strength of the limiting plate 9 and the tooth base, but at this time, the overflow of hydraulic oil from the gap between the positioning groove and the tooth base cannot be avoided, that is, the sealing of the entire hydraulic chamber cannot be guaranteed.

[0042] Therefore, a sealing pad 5 is fixed between the side of the tooth base close to the blade 2 and the outer side of the blade 2, the sealing pad 5 is made of elastic material, and the sealing pad 5 can seal the sealing between the tooth base and the blade 2, and there is no risk of leakage between the tooth base and the limiting plate 9 because of the fixed arrangement, and the limiting plate 9 and the blade 2 are in sliding fit, so that the overflow of hydraulic oil from the gap between the limiting plate 9 and the blade 2 can be prevented, and the sealing of the hydraulic chamber is finally guaranteed by the above arrangement.

[0043] In actual application, in order to guarantee the sealing between the limiting plate 9 and the blade 2, a sealing strip can be fixed on the side of the limiting plate 9 away from the tooth base, and a limiting groove in sliding fit with the limiting plate 9 is formed in the blade 2, and the sealing strip slides in the limiting groove under the action of the limiting plate 9, so as to avoid the overflow of hydraulic oil.

[0044] In some embodiments of the high-efficiency energy-saving PDC drill bit provided in the application, please refer to Figure 2 The limiting plate 9 is integrally formed with the tooth base. The connecting strength of the limiting plate 9 and the tooth base is the key to ensure the position stability of the tooth base and the first cutting tooth 3. Therefore, the limiting plate 9 is integrally formed with the tooth base, and the limiting plate 9 can always tightly match the limiting groove on the blade 2. Through the above setting, the force acting on the first cutting tooth 3 can be effectively applied to the blade 2 through the limiting plate 9.

[0045] In actual application, a certain amount of hydraulic oil is injected into the hydraulic cavity. During drilling, even if the tooth base swings a certain angle under the action of the hydraulic oil, the first cutting tooth 3 will still be subjected to the force from the formation to the base 1. The hydraulic oil in the hydraulic cavity can have a certain force on the tooth base, and the effect of the force is to ensure that the tooth base and the blade 2 remain relatively stable.

[0046] In some embodiments of the high-efficiency energy-saving PDC drill bit provided in the application, please refer to Figure 2 The outer side of the limiting plate 9 is provided with a blocking pad 8, which is arranged between the tooth base and the blade 2 to prevent impurities from contacting the limiting plate 9.

[0047] Before the hydraulic oil is injected, the vertical distance between the top of the first cutting tooth 3 and the base 1 is greater than the vertical distance between the top of the second cutting tooth 4 and the base 1. In this case, the drilling is mainly performed by the first cutting tooth 3, and the second cutting tooth 4 is in an idle state. After the hydraulic oil is injected into the hydraulic cavity through the oil hole 6, the volume of the hydraulic cavity will increase. Since the bottom of the tooth base abuts and is positioned in the positioning groove, the tooth base will swing a certain angle with the contact point of the positioning groove as the center under the cooperation of the limiting plate 9. In the process of movement of the tooth base, the limiting plate 9 slides out of the blade 2. At the same time, the vertical distance between the top of the first cutting tooth 3 and the base 1 is less than the vertical distance between the top of the second cutting tooth 4 and the base 1, which makes the first cutting tooth 3 give way to the second cutting tooth 4, so that the second cutting tooth 4 plays a major role in drilling. Since the first cutting tooth 3 and the second cutting tooth 4 are different types, different drilling effects are produced.

[0048] Since the limiting plate 9 will move relative to the blade 2, in order to avoid that the limiting plate 9 brings impurities in the external formation into the blade 2, causing unstable movement or wear of the limiting plate 9. The blocking pad 8 is arranged between the blade 2 and the tooth base. The blocking pad 8 also has a certain elasticity and is made of water-proof material, which has a certain isolation effect.

[0049] In some embodiments of the high-efficiency energy-saving PDC drill bit provided in the application, please refer to Figure 2The oil pump is communicated with one end of the oil hole 6, and the oil pump injects hydraulic oil into the hydraulic cavity through the oil hole 6 for swinging the tooth base, and the oil pump reduces the pressure in the hydraulic cavity by sucking the hydraulic oil for positioning the tooth base on the blade 2.

[0050] During drilling, the stratum has an acting force on the first cutting tooth 3, and the acting force on the first cutting tooth 3 is partially applied to the blade 2 through the positioning groove, is partially applied to the blade 2 through the limiting plate 9, and finally is applied to the blade 2 through the hydraulic oil, and the injection of the hydraulic oil, that is, the acting force of the hydraulic oil on the tooth base can ensure the relative stability of the tooth base.

[0051] The hydraulic oil is injected into the hydraulic cavity through the oil pump, but when the acting force of the stratum on the first cutting tooth 3 decreases or the drill bit is retracted, the limiting plate 9 and the positioning groove are difficult to provide the acting force on the tooth base in the direction close to the blade 2, which may cause the tooth base to be separated from the positioning groove. In order to avoid the above problems, when it is detected that the acting force of the stratum decreases, the hydraulic oil is timely extracted through the oil pump, and when the drill bit is extracted from the stratum, negative pressure can be generated in the hydraulic cavity through the oil pump, so that the tooth base is stably positioned on the blade 2 under the action of atmospheric pressure.

[0052] In some embodiments of the high-efficiency energy-saving PDC drill bit provided in the application, please refer to Figure 2 The number of the oil holes 6 is multiple, and the multiple oil holes 6 are all communicated with the oil pump, and the oil pump is used for swinging the corresponding multiple tooth bases by a certain angle through the multiple oil holes 6.

[0053] The oil hole 6 in the application corresponds to the tooth base one by one, and since the drill bit is in a rotating state during drilling, if one of the tooth bases is deflected by a certain angle alone, the entire drill rod will bear a certain non-axial force during drilling of the drill bit, which causes the drill bit to be unable to continuously and stably rotate.

[0054] Therefore, in the application, the multiple oil holes 6 are simultaneously communicated with the oil pump, and the same amount of hydraulic oil is injected into the hydraulic cavity under the action of the oil pump, so that the multiple tooth bases can swing by a certain angle at the same time.

[0055] In some embodiments of the high-efficiency energy-saving PDC drill bit provided in the application, please refer to Figure 2 The control valve is used for opening or closing the oil hole 6 to prevent the hydraulic oil from flowing back into the oil pump during drilling.

[0056] In the process of drilling, the position of the first cutting tooth 3 relative to the base 1 is kept unchanged for a certain period of time, but at this time the stratum still has a certain force on the first cutting tooth 3, which continuously extrudes the hydraulic oil in the hydraulic chamber. Since the hydraulic oil in the plurality of hydraulic chambers flows to the oil pump at the same time, it finally affects the specifications and normal operation of the oil pump.

[0057] In order to solve this problem, a control valve is arranged at the end of the plurality of oil holes 6, and the hydraulic oil in the oil pump flows into the corresponding hydraulic chamber through the control valve. When the control valve is closed, the hydraulic oil in the hydraulic chamber can be blocked, and the position of the tooth base and the first cutting tooth 3 is stabilized.

[0058] The above is only a preferred embodiment of the present application, and is not used to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A high efficiency and energy saving PDC bit, characterized in that, The utility model relates to a cutting tool, which comprises: a base; a plurality of blades arranged circumferentially along the base and fixed to the top of the base; a plurality of tooth bases corresponding to the plurality of blades, the tooth base being hingedly connected to one side of the corresponding blade, and a hydraulic cavity being formed between the tooth base and the blade; a plurality of first cutting teeth fixed to the plurality of tooth bases, respectively; a plurality of second cutting teeth fixed to the top of the plurality of blades, the hardness and structural strength of the second cutting teeth being greater than those of the first cutting teeth; an oil hole formed in the base and the blade, the oil hole being in communication with the hydraulic cavity, the oil hole being used to introduce hydraulic oil into the hydraulic cavity to make the tooth base swing, and the first cutting teeth being swung to the inner side of the second cutting teeth by the tooth base to make the second cutting teeth drill; a positioning groove formed in the blade, the tooth base being abutted against and swung in the positioning groove; a limiting plate fixed to the tooth base, the side of the limiting plate away from the tooth base extending into the blade, the limiting plate being inserted into the blade and cooperating with the positioning groove to limit the swinging direction of the first cutting teeth; a positioning groove formed in the outer side of the limiting plate, a limiting block fixed to the blade, the limiting block extending into the positioning groove and slidingly cooperating with the positioning groove, the limiting block being used to prevent the limiting plate from sliding out of the blade through the positioning groove; one end of the oil hole being in communication with an oil pump, the oil pump being used to inject hydraulic oil into the hydraulic cavity through the oil hole to make the tooth base swing, and the oil pump being used to reduce the pressure in the hydraulic cavity by sucking hydraulic oil to make the tooth base be positioned on the blade.

2. The energy efficient PDC bit of claim 1, wherein, a sealing gasket being arranged between the blade and the tooth base, the sealing gasket, the blade, the tooth base, and the limiting plate forming a sealed hydraulic cavity.

3. The energy efficient PDC bit of claim 1, wherein, the limiting plate and the tooth base being integrally formed.

4. The energy efficient PDC bit of claim 1, wherein, an isolation pad being arranged on the outer side of the limiting plate, the isolation pad being arranged between the tooth base and the blade to prevent impurities from contacting the limiting plate.

5. The energy efficient PDC bit of claim 1, wherein, the number of the oil holes being a plurality, the plurality of oil holes being in communication with the oil pump, and the oil pump being used to make the corresponding plurality of tooth bases swing by a certain angle through the plurality of oil holes.

6. The energy efficient PDC bit of claim 5, wherein, three oil holes being in communication with the oil pump through a control valve.

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