RU2541414C2 - Hybrid drill bit with high ratio between diameters of guide stud and journal - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: set of inventions relates to hybrid drill bits. Proposed hybrid drill bit comprises the part that follow: shank to be coupled with drilling string and supports of fixed cutters connected with said shank. Fixed cutting blades are rigidly connected with cutter supports at definite distance from said stem and comprise several cutting elements extending from the surfaces of blades. Legs of truncated-cone rolling cutters are attached to said shank and comprises axles with central line that have the journal arranged around said central and having a definite diameter. Guide stud is connected with the journal to extend in central line towards lengthwise axial line. Assemblies of rolling cutters attached to said legs nearby fixed cutting blades to run on said journal and guide stud relative to said shank around central line. Note also that said assemblies comprise cutting elements spaced from their surface. Ratio of guide stud diameter to journal diameter is equal to, greater than 0.58 and smaller than 1.0.

EFFECT: higher permissible load at hybrid drill bit.

11 cl, 6 dwg

Description

Priority Claims

This application claims the priority of patent application US 61/139392, filed December 19, 2008, and patent application US 12/481410, filed June 9, 2009. These applications are incorporated into this description by reference.

Technical field

In General, the present invention relates to drill bits intended for drilling underground rocks, and more particularly to a hybrid drill bits, devices and method for increasing the strength of the supporting surfaces in such drill bits.

State of the art

Drill bits are often used in oil and gas exploration and mining for drilling wells (also called "boreholes") in underground formations. There are two common types of drill bits used to drill wells, known as “fixed cutter” and “cone” drill bits. Polycrystalline diamond inserts (PKA) and other blade-type drill bits are used in fixed-cutter drill bits. These drill bits typically include a bit body having an external thread at one end for connection to the drill string, and several cutting blades extending from the opposite end of the bit body. The cutting blades form the cutting surface of the drill bit. Typically, in the blades of the bit are fixed or inserted into them several cutting elements, for example, cutters from PKA or other materials with sufficient hardness and strength to deform and (or) cut through the ground rocks that protrude from the bit and form its cutting profile. This set of cutting elements is used to cut underground rocks during drilling operations when the drill bit is rotated by an engine or other rotating device.

Another type of drill bit, called a cone bit, usually includes a bit body with an external threaded connection at one end and several cones (usually three) attached to the other end of the drill bit at an angle to the centerline of the bit. These cones can rotate on bearings, each separately, relative to the body of the bit.

Particular examples of a cone bit and cone are shown in FIGS. 1 and 2 and are described in US 6,601,661, incorporated herein by reference. The cone bit 10 includes a bit body 12 with a longitudinal center line 8 and a connector 14 in the form of a threaded pin at the upper end for attaching the bit body 12 to the lower end of the drill string (not shown). The body 12 of the bit usually has three legs extending down (the two shown are designated 16, 18), each of which has lubricant compensators 20. Flushing nozzles 22 are located between adjacent paws for supplying drilling fluid during drilling. The drilling fluid is pumped down the drill string into the cavity in the body 12 of the bit. A cone is attached to the lower end of each of the three paws. Figure 1 shows three conical cones 24, 25 and 26, mounted rotatably to the lower ends of the legs of the body 12 of the bit.

The roller cone 24 is held by bearings 27 on an axis 28 having a central (axial) line 6 located at an angle to the longitudinal axial line 8 of the bit body. The axis 28 includes a pin 29 and a guide pin 30 with a protrusion 31 formed between the pin 29 and the guide pin 30. The diameter surfaces of the pin 29 and the guide pin 30 serve as a cone support under radial (bending) loads, and the surface of the protrusion and, sometimes, the end surface of the guide pin serve as a support for the cone under axial (end) load. The diameter and length of the trunnion, the diameter and length of the guide pin and the size of the protrusion formed between them are limited by the size and shape of the cone attached to them. For a given pin diameter, an increase in the diameter of the guide pin either leads to the need to reduce the total length of the pin and / or guide pin or to reduce the thickness of the cone body. Both can lead to an accident. Similarly, a too small surface of the protrusion can cause damage to the axis and the junction with the cone cone.

The cone 24 includes a cone body 32, usually made of properly hardened steel. The cone body 32 is generally generally conical in shape. Several main cutting elements 34, 36, 28 protrude from the cone body 32. When the cone body 32 rotates around the axis 28, the main cutting elements capture the rock inside the well and crush it. Several cutting elements can be represented by one or a combination of milled steel teeth (chisels with steel teeth), inserts made of tungsten carbide or other hard materials (carbide chisels) or several other elements formed and having different shapes from materials whose hardness and strength are sufficient for deformation and eruption of underground rocks. In some cases, carbide hardening material is applied to the outer surface of the cutting elements and (or) other parts of the cone drill bit to reduce wear of the bit during operation and increase its service life.

The drill bits of the described types are inherently limited, especially with respect to the life of the bit and the types of underground rocks that they can drill. Fixed-cutter bits, such as PKA bits, can usually be successfully used for rocks from the softest to medium hard and non-abrasive rocks of medium hardness. Hard and / or abrasive rocks are generally considered unsuitable for PKA cutters due to their excessive wear and reduced service life when drilling such rocks. For example, drilling shale and silt is easy; sandstone drilling, especially coarse-grained and consolidated, is too complex to be cost-effective, and is accompanied by the destruction of fixed-cutter drill bits [see, for example, Feenstra, R. et al., “Status of Polycrystalline-Diamond-Compact Bits: Part 1 - Development "and" Part 2 - Applications ", Journal of Petroleum Technology, Volume 40 (7), pp. 675-684 and 817-856 (1988)]. Success here depends entirely on the right combination of drill bit, drilled rock and working conditions. Experience has shown that for bits with fixed cutters, for example PKA bits, the type of mud, the hydraulics of the bit and the design of the bit affect the work, the bit is much stronger than changes in the properties of the clay solution.

Long-term experience in drilling shows that it is more correct to develop a bit design that is most suitable for a particular field than choosing from an existing set. Increased drill bit aggressiveness is not always desirable due to the increased torque requirements associated with it. The ability to develop and (or) adapt a bit for a specific drilling operation or application is an invaluable tool for a bit designer. So, in recent years, attempts have been made to develop bits for drilling terrestrial rocks, in which a combination of one or more cones with one or more fixed cutting blades is used, on which PKA or similar abrasive cutting elements are formed or fixed. Some of these combined type bits are called "hybrid drill bits."

One previously described hybrid drill bit is disclosed in US Pat. No. 4,343,371, which is a hybrid rock for solid rock, "wherein a pair of opposing elongated paws of a blade bit with flushing nozzles are located next to a pair of opposing cones with tungsten carbide. An elongated end with flushing nozzles near the bottom of the well is installed a large number of diamond inserts. Diamond inserts are specially positioned so as to remove ridges between rows of grooves in the bottom of the well cut by inserts on cones. " In the aforementioned patent, the cross section of the guide pin and pin is not shown, however, it is usually similar to that of a cone bit.

Significant stresses arise in the trunnion and guide pin when radial (bending) and axial (compressive) loads are applied to the drill bit during drilling operations. The trunnion and the guide pin each carry a radial load, each along its length, acting across the center line of the axis, and the end surface between the trunnion and the guide pin carries an axial load acting parallel to the center line of the axis. In a hybrid drill bit, the cone assembly is generally smaller in size at a given cutter size than the corresponding cone bit, since the hybrid drill bit must accommodate both cone units and adjacent fixed cutting blades. The trunnion and guide pin, around which the cone assembly rotates, are forced to get smaller, which leads to greater stresses at the same stresses on a smaller area. However, stresses arising in the cone assembly require a certain minimum thickness of the cone body material, which limits the size and length of both the trunnion and the guide pin. For example, increasing the diameter of the guide pin requires decreasing the length of the pin to accommodate a larger diameter pin inside the cone assembly, or requires reducing the wall thickness of the cone assembly.

Thus, there remains a need to increase the permissible load of the hybrid drill bit.

Disclosure of invention

The invention disclosed and described herein relates to an improved hybrid drill bit having at least two truncated cone cone nodes (in the form of a truncated cone), each of which rotates on the bit around a separate axis, and at least two fixed cutting blades adjacent to nodes of truncated-conical cone, and related elements. In the improved drill bit, the ratio of the diameters of the guide pin and pin in the case of the truncated cone assembly within the allowable space inside the truncated cone assembly has been increased.

The disclosure provides a hybrid drill bit for use in underground drilling, including: a shank located around a longitudinal center line and adapted to be connected to the drill string; at least two supports of fixed incisors connected to the shank; at least two fixed cutting blades rigidly connected to the supports of the cutters at a distance from the shank, including several cutting elements extending from the surface of the blades; and at least two truncated cone cone assemblies attached to the legs of the truncated cone cone far from the shank close to the fixed cutting blades and adapted to rotate relative to the shank around the center line of the axle on the pin and the guide pin, while the cone assemblies include cutting elements spaced from the surface of the nodes. The axis on the legs of the truncated-conical cone includes a trunnion located around the center line of the axis and having a trunnion diameter; and a guide pin connected to the pin and extending along the centerline of the axis toward the longitudinal center line, having a diameter of the guide pin, wherein the ratio of the diameter of the guide pin to the diameter of the pin is equal to or greater than 0.58.

The invention provides a hybrid drill bit for use in underground drilling, including: a liner located around a longitudinal center line and adapted to be connected to a drill string; at least two supports of fixed incisors connected to the shank; at least two fixed cutting blades rigidly connected to the supports of the cutters at a distance from the shank, including several cutting elements extending from the surface of the blades; and at least two trunnion-cone fastening legs attached to the shank, including an axis, the center line of which extends at an angle to the longitudinal axial line in the direction of the longitudinal axial line. The axis includes a trunnion located around the center line of the axis and having a trunnion diameter; and a guide pin connected to the pin and extending along the centerline of the axis toward the longitudinal center line, having a diameter of the guide pin, wherein the ratio of the diameter of the guide pin to the diameter of the pin is equal to or greater than 0.58.

Brief Description of the Drawings

The following drawings are part of the description and are included to illustrate some features of the present invention. The invention will be better understood by reference to these drawings in combination with a detailed description of the specific embodiments presented here:

figure 1 presents a side view of a typical roller cone bit;

figure 2 presents a side view in cross section of the configuration of the trunnion and the guide pin of a typical cone bit;

figure 3 presents a side view of a private variant of a hybrid drill bit;

4 is a bottom view of a particular embodiment of a hybrid drill bit;

figure 5 presents a side view in section of a particular configuration with an increased ratio of the diameter of the guide pin to the diameter of the trunnion in accordance with the invention;

figure 6 presents a side view in section of another private configuration with an increased ratio of the diameter of the guide pin to the diameter of the trunnion in accordance with the invention.

While the invention disclosed herein is susceptible of various modifications and alternative forms, only some particular embodiments will be described in detail below by way of example.

Detailed Description of the Invention

The above-described figures of the drawings and the following description of specific structures and functions are not intended to limit the scope of the invention or the scope of the appended claims. On the contrary, the drawings and description are intended to show any person skilled in the art how inventions for which patent protection is claimed can be made and used. Those skilled in the art will appreciate that for brevity and better understanding, not all features of industrial embodiments of the inventions are described or shown. Professionals should also be clear that the development of real structures, including the features of the present invention, to achieve the development goals for an industrial design will require numerous solutions, due to a specific implementation option. Such decisions, due to a specific implementation option, may include compliance with systemic, business, regulatory, and other constraints, although they are most likely not limited to them. These restrictions may differ for a particular embodiment, location, and over time. Although the tasks facing the developer will be complex and time-consuming in absolute terms, the use of this disclosure for a specialist will make solving these problems a normal job. It should be understood that the invention disclosed and described herein may have various modifications and alternative forms. And finally, the use of the term in the singular, for example, expressed as an indefinite article or otherwise, does not imply a limitation on the number of elements. In addition, terms expressing relationships, for example, “top,” “bottom,” “left,” “right,” “top,” “bottom,” “down,” “up,” “side,” and others are used in the description. to clarify specific references to the drawings and do not imply limitation of the scope of the claims of the invention or the attached claims. The terms “connect”, “connected”, “connecting”, “connector” and other similar terms are used here in a broad sense and may include any method and device for fixing, binding, fastening, attaching, attaching, connecting, installation inside, forming outside or inside, establishing a connection or forming a connection in another form, for example, mechanical, magnetic, electrical, chemical, directly or indirectly through intermediate elements, one or more elements, and may also include, without limitation, and integration is one functional member with another in a single unit. The connection can occur in any direction, including rotational.

The applicants have proposed an improved hybrid bit and related elements with an increased ratio of the diameters of the guide pin and trunnion inside the body of the truncated cone assembly, including at least two truncated cone cones, each of which can rotate around a separate axis on the bit, and at least two fixed cutting blades near the nodes of the truncated cone cone.

Figure 3 presents a side view of a private example of a hybrid drill bit. 4 is a bottom view of a particular example of a hybrid drill bit. Figure 5 presents a view of a particular example of a configuration with an increased ratio of the diameters of the guide pin and trunnion in accordance with the disclosure. Figure 6 presents a view of another private example configuration with an increased ratio of the diameters of the guide pin and trunnion in accordance with the disclosure. Description of these drawings will be carried out jointly.

The hybrid drill bit 50 has a longitudinal center line 52 defining a central axis of the hybrid drill bit. A shank 54 is formed at one end of the hybrid drill bit to be connected to the drill string from pipes (not shown) and threaded in accordance with standards implemented by the American Petroleum Institute. At least two support 56 of the bit with fixed cutters down in the direction of the general orientation of the bit inside the borehole extend from the shank 54. At the end of the hybrid drill bit, remote from the shank 54, the fixed cutter supports 56 move into the fixed cutting blades 58.

Several cutting elements 60, 62 of fixed blades are located and fixed on the surface 63 on each of the fixed cutting blades 58, for example, on the leading edges of the hybrid drill bit with respect to the direction of rotation. Typically, the fixed blade cutting elements 60, 62 include a polycrystalline diamond layer or plate (PCA) on the leading surface of the supporting substrate, the diamond layer or plate forming a cutting surface having a cutting edge along its edge to trap the rock. The term PCA is used in a broad sense and includes other materials, for example, disks or plates made of thermostable polycrystalline diamond, mounted on tungsten carbide substrates, or other similar superabrasive or superhard materials, for example cubic boron nitride and carbon with a diamond-like structure. The cutting elements 60, 62 of the fixed blades can be soldered by refractory solder or otherwise fixed in sockets or "pockets" on each fixed cutting blade 58 so that their outer or cutting edges on the cutting surfaces are facing the rock.

Hybrid drill bit 50 also includes at least two legs 64 truncated-cone cones and attached to them two nodes 72 truncated cone cones. The paws 64 of the truncated cone cones, by analogy with the supports 56 of fixed incisors, extend from the shank 54 down in the direction of the general orientation of the bit inside the borehole. Each of the legs 64 of the truncated-conical cones ends with an axis 66 at the far end of the legs. Axis 66 has a center line 67 around which an axis is symmetrically formed. The center line 67 of the axis is generally at an angle to the longitudinal center line 52 (usually at an angle of 51-59 degrees to the longitudinal center line, that is, at an angle of 31-39 degrees to the horizontal, provided that the longitudinal center line is perpendicular to the horizontal plane) and runs towards the longitudinal center line. In at least one embodiment, the center axis line 67 may intersect the longitudinal center line 6. However, other angles and directions may be used, including directions away from the longitudinal center line.

On the axis 66, basically two parts are formed - a pin 68 located at the base of the axis, and a guide pin 70 adjacent to the pin and extending coaxially with it along the axis center line 67. The protrusion 71 is formed between the pin 68 and the guide pin 70 due to the difference in their diameters. The trunnion, the guide pin and the protrusion serve as a support for the truncated-cone roller assembly 72 placed on the trunnion and the rotatable pin.

A truncated cone cone assembly 72 is typically mounted on each axis 66. The truncated cone cone assembly 72 typically has a cut nose section 73, in contrast to the typical cone cone bit shown in FIG. The truncated cone cone assembly 72 is adapted to rotate around axis 66 when the hybrid drill bit 50 is rotated by the drill string through the shank 52. Typically, several cutting elements 74, 75 are attached to the surface of the cone assembly 72. At least some of the cutting elements are typically located along node 72 truncated-conical cone in circular rows. The minimum distance between the cutting elements will be determined by the nature of the application and the size of the bit and can vary from one cone assembly to another and (or) from one cutting element to another. Some cutting elements may be placed “randomly” on the surface of the cone assembly. Cutting elements may include tungsten carbide inserts mounted on a tight fit into holes in the surface of the cone assembly, milled cutting elements or cutting elements in the form of steel teeth with welded carbide cutting elements that are integral with the cone assembly and protruding above its surface, and cutting elements of other types. The cutting elements may be made of superabrasive or superhard materials, for example polycrystalline diamond, cubic boron nitride, etc., or may have appropriate coatings. The cutting elements may have a pointed shape, as shown in the drawings, a conical, round or oval or other shape or a combination of shapes depending on the application.

In the hybrid drill bit, the cutting elements 60, 62 of the fixed cutting blade 58 and the cutting elements 74, 75 of the truncated cone assembly 72 together define a matching cutting surface in the leading portions of the hybrid drill bit profile. The cutting elements 74, 75 of the cone assembly 72 are crushed and the materials of the underground rock are preliminarily or partially crushed by high-stressing leading regions, easing the load on the cutting elements 60, 62 of the fixed cutting blade 58.

Ball bearing 80 may facilitate rotation of the cone assembly on an axis. One or more sealed or unsealed angular contact bearings 82, 84 form a segment of the engagement surface along the center line of the axis, allowing rotation of the cone assembly 72 on axis 66, and perceiving a radial (bending) load. Bearings may include plain bearings, roller bearings, floating sleeves, shrink sleeves, and other types of bearings and materials. In some embodiments, the thrust bearing 86 may be placed on a protrusion or end of a guide pin to absorb axial load and facilitate rotation of the truncated cone cone assembly about an axis when the cone assembly rests on a protrusion or end of the guide pin.

The cone assembly 72 typically includes a seal 88 located between the axis 66 and the internal cavity of the truncated cone assembly. The sealant may be of a well-known type, for example an elastomeric sealant and a metal end seal.

It is understood that other elements of the hybrid drill bit, for example, incisors with a longitudinal forward inclination, wear-resistant surfaces, flushing nozzles used to direct the flow of the drilling fluid, grooves for the removal of drill cuttings, which provide cleaning from rock fragments and drilling mud, and other generally accepted elements of the drilling bits are known to specialists and do not require special consideration.

After describing the general features of the hybrid drill bit, consider the axis with a pin, a guide pin and a protrusion. The trunnion, guide pin and protrusion are subjected to radial and axial loads when a hybrid drill bit is used for underground drilling. It is important to increase the diameters of the trunnion and the guide pin relative to the protrusion and to extend the trunnion and the guide pin without deteriorating the strength of the truncated cone assembly due to excessive reduction in the thickness of the cone assembly body or reduction of the bearing surfaces on the axis.

For conventional roller cone designs, such as those shown in FIGS. 1 and 2, there are generally accepted certain restrictions on the size of the trunnion, guide pin and protrusion for a given cone size. These dimensions were limited by the shape and configuration of the cone and the minimum thickness of the casing, which can withstand the loads acting on the cone. A measure of the relative diameters of the guide pin and trunnion can be expressed as a ratio. Typically, this ratio is about 0.50 and does not exceed 0.56. When using a larger ratio, the bearing length is usually reduced for a given pin diameter or an unwanted reduction in the thickness of the roller cone housing is required.

To the best knowledge of the inventors, the same ratios have so far also been used in hybrid drill bits in accordance with industry standards. This happened despite the need to achieve maximum diameters and lengths of the trunnion and guide pin. Thus, an increase in the ratio of the diameters of the guide pin and pin beyond the standard value of less than 0.56 was not an obvious proposal.

The authors of the present invention reconsidered from the very beginning the question of the diameters of the trunnion and the guide pin and their ratios, as applied to the thickness of the body of the truncated cone assembly, and found that these ratios for the truncated cone assembly can be changed. This change is especially important in the case of a hybrid drill bit, since the size of the truncated cone assembly is usually smaller for a hybrid drill bit of a certain size than for the corresponding roller bit. On the hybrid drill bit, both truncated cone cone units and adjacent fixed cutting blades should be placed, as a result of which the pin and guide pin are reduced in size and high stresses occur at the same loads.

The inventors have found that contrary to popular belief, the ratio of the diameters of the guide pin and pin (P: J ratio) can be increased to a value of at least 0.58 to 1.0 inclusive, including P: J ratios of approximately 0, 60, about 0.62, about 0.64, about 0.66, about 0.68, about 0.70, about 0.72, about 0.74, about 0.76, about 0.78, about 0, 80, about 0.82, about 0.84, about 0.86, about 0.88, about 0.90, about 0.92, about 0.94, about 0.96, about 0.98, and also the values in this range for example (no limited i) P: J ratios ranging from about 0.71 to about 0, 95, or from about 0.83 to about 0.99, inclusive. With a ratio of 1.0, the diameter of the guide pin 70 becomes equal to the diameter of the journal 68 and parts of the axis merge to form a continuous surface. As the diameter of the guide pin 70 increases, the surface area of the protrusion 71 decreases. However, the guide pin itself can absorb axial loads with its end mating with the truncated cone assembly. As shown above, a thrust bearing 86 may be installed between the guide pin 70 and the roller cone assembly 72. Furthermore, P: J ratios greater than 1.0 are possible when the diameter of the guide pin is larger than the diameter of the journal.

When calculating the ratios, angular contact bearings, if any, can be taken into account. So, if there is an angular contact bearing 82 on the pin having a contact surface along the center line of the axis and receiving a radial load, the thickness of the bearing taking the radial load can be taken into account in the effective diameter of the pin for further comparison with the diameter of the guide pin. Similarly, an angular contact bearing 84 on a guide pin, a segment of the engagement surface of which extends along the center line of the axis, can actually form a larger guide pin and, as a result, an increased diameter of the guide pin can be used in calculating the ratio.

Other and further embodiments in which one or more of the features of the above inventions are used may be proposed within the spirit of the present invention. For example, various angles of inclination of the center line of the axis may be used. Several bearings can be installed, for example, two ball bearings spaced apart along the length of the journal and / or guide pin to form an enlarged segment of the engagement surface between the bearings along the center line to absorb radial loads and used to calculate the ratio of the diameters of the guide pin and journal . In addition, various methods and embodiments of the hybrid drill bit in combination with each other can be used to obtain various embodiments of the disclosed methods and embodiments. Consideration of individual elements may apply to many elements and vice versa.

The procedure for performing any steps presented here in explicit or implicit form may have a different sequence, unless otherwise specifically agreed. The various steps described here can be combined with other steps, inserted between existing steps and / or broken down into several steps. Similarly, the elements were described functionally and can be implemented as separate components or can be combined into components having several functions.

The inventions have been described with reference to preferred and other embodiments, but not every embodiment has been described. Obvious modifications and changes to the described embodiments are available to those skilled in the art. Disclosed and undisclosed embodiments do not imply a limitation on the scope of the claims or application of the invention, on the contrary, in accordance with patent law it is intended to protect all such modifications and improvements falling within the scope of claims or equivalents of the claims below.

Claims (11)

1. Hybrid drill bit for use in drilling underground rocks, including: a shank located around a longitudinal axial line and adapted for connection with a drill string; at least two supports of fixed incisors connected to the shank; at least two fixed cutting blades rigidly connected to the supports of the cutters at a distance from the shank and including several cutting elements extending from the surface of the blades; at least two legs of a truncated cone cone attached to the shank and including axes with a central line, comprising a trunnion located around this center line of the axis and having a trunnion diameter, and a guide pin connected to the trunnion and extending from it along the center axis the side of said longitudinal center line, wherein the ratio of the diameter of the guide pin to the diameter of the pin is equal to or more than 0.58 and less than 1.0; and at least two truncated cone cone assemblies attached to the claws of the truncated cone cones far from the shank and close to the fixed cutting blades rotatably on the axle and guide pin relative to the shank around the center line of the axis, while the cone assemblies contain spaced apart their surface cutting elements. 2. The hybrid drill bit according to claim 1, further comprising a bearing located around the journal, guide pin, or combinations thereof and having a segment of the engagement surface along the center line of the axis with the journal, guide pin, or a combination thereof. 3. The hybrid drill bit according to claim 2, in which the ratio of the diameter of the guide pin to the diameter of the pin is calculated taking into account the bearing on the pin, guide pin or a combination thereof. 4. The hybrid drill bit according to claim 1, in which the nodes of the truncated-conical cones include a cut nose section. 5. The hybrid drill bit according to claim 1, in which the guide pin has a stop surface perpendicular to the center line of the axis. 6. The hybrid drill bit according to claim 1, in which the center line of the axis is located at an angle from equal to or greater than 51˚ to less than or equal to 59˚ relative to the longitudinal center line of the shank. 7. Hybrid drill bit for use in drilling underground rocks, including: a shank located around a longitudinal center line and adapted for connection with a drill string; at least two supports of fixed incisors connected to the shank; at least two fixed cutting blades rigidly connected to the supports of the cutters at a distance from the shank, including several cutting elements extending from the surface of the blades; and at least two legs of a truncated-cone cone attached to the shank and including an axis with a center axis line containing a pin located around the center line of the axis and having a pin diameter, and a guide pin connected to the pin and extending from it along the center line of the axis in the direction of the aforementioned longitudinal center line, the ratio of the diameter of the guide pin to the diameter of the journal equal to or more than 0.58 and less than 1.0. 8. The hybrid drill bit according to claim 7, further comprising a bearing located around the journal, guide pin, or combinations thereof, and including a segment of the engagement surface along the center line of the axis with the journal, guide pin, or a combination thereof. 9. The hybrid drill bit according to claim 7, in which the ratio of the diameter of the guide pin to the diameter of the pin is calculated taking into account the bearing on the pin, guide pin or a combination thereof. 10. The hybrid drill bit according to claim 7, in which the guide pin has a stop surface perpendicular to the center line of the axis. 11. The hybrid drill bit according to claim 7, in which the center line of the axis is located at an angle from equal to or greater than 51 ˚ to less than or equal to 59 ˚ relative to the longitudinal axial line of the shank.

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