RU2077652C1 - Drill head - Google Patents

Abstract

FIELD: well drilling. SUBSTANCE: drill head is assembled of a set of blades different in functional application. The first function is coarse annular well drilling out of the well bottom. The second function is well wall calibration, core roll calibration and cutting the core so as to apply minimum axial load, keep diameter of the well and core. As this takes place, tubular cutters with holes open to drill string-borehole annulus. EFFECT: higher efficiency. 6 cl, 4 dwg

Description

 The invention relates to a rock cutting tool, namely, bits for core drilling of deep and superdeep wells with coring (rock sample), having dimensions that ensure the implementation of all the necessary research complex. Drilling with coring is more difficult than continuous drilling, since it requires combining in optimal proportions two opposite processes: destruction (drilling) of the annular zone of the surface of the bottom of the well with the highest possible rate and maintaining the integrity of its central core, which is achievable only with the rational design of the drill head and core tools in general.

 All well-known drill heads (cone, blade, milling, and other types) [1] are prefabricated, all-welded or cast structures with undivided or partially separated by element functions. So, a single blade (for example, cone) is a detachable connection, however, its elements are not adapted separately, which means it is most effective to solve the problems of drilling the annular space of the bottom of the well, calibrating its wall (well-forming), calibrating and cutting the core (core-forming). They are equipped with cutters having a prismatic (rectangular) or round shape like pins, separated along the cylinder generatrix by channels for transporting cuttings. The incisors are cooled irrationally, over time, the area of their contact with the breed increases. The shape of the cutters, their number and location necessitate the application of relatively large axial loads on the bit, increasing as the well deepens.

 Imperfect are such geometric design parameters of modern drill heads as the core reception height (distance from the core formation zone to the core explorer) and core reception coefficient (relative to this core diameter distance). The low percentage of core removal is the result of imperfections in the design of burgole traps and core cutters.

 The purpose of the invention is to increase the productivity of the drill head while maintaining a given quality of core formation and coring by means of a greater depth of penetration of its cutters into the rock under equal normalized conditions of its operation.

 This goal is achieved in that the drill head [2] includes a housing, interchangeable interchangeable blades with internal bores and grooves for their stop, characterized in that one of the blades is made with cutters for rough annular drilling of the bottom of the well, and others, respectively, for calibration borehole wall, core and its cutting; the blade cutters are made of carbide material and have a tubular shape, and their holes are in communication with the annulus; cutters for rough ring drilling are pressed into the body of the blade, insulated with a soft jumper with the possibility of preventing them from touching the well wall in the transport position of the bit; one of the blades is made with a vertical hole in which a slider with a slanted groove spring loaded by a compression spring is installed, and with a horizontal hole in which the cutter is located with the possibility of its automatic extension to the well wall; the second blade is made with a vertical hole in which a slider spring-loaded with a compression spring is installed with an inclined groove and a horizontal hole in which the cutter is located with the possibility of its automatic extension to the outer surface of the core; the third blade is made with a vertical hole in which a slider spring-loaded with a compression spring is installed with an inclined groove and a horizontal hole in which the cutter is located with the possibility of its automatic extension to the outer surface of the core at the time of completion of drilling and the beginning of the lifting of the core sample at the wellhead.

 In FIG. 1, FIG. 2, FIG. 3, FIG. 4 shows, respectively, longitudinal sections: of the proposed burgole head and its bottom view, on which a blade for rough annular drilling of the bottom of the well and a blade for core calibration are visible; and separately made blades for calibrating the borehole wall and core cutting.

 The burgolovka consists of a housing 1 and blades 2 and 3, which make up the main design variant. The housing has threads 4, 5 and annular grooves 6 and 7 for connecting the blades to the housing and the entire drill head to the drill pipe, respectively. The blade 2 has vertical step openings at the end, containing, by pressing, carbide cutters of tubular shape 8 and 9, the openings of which are in communication with horizontal openings 10 and 11, made in the body of the bit and the blade and designed to evacuate cuttings into the annulus.

 The blade 3 has in the end a blind vertical hole 12 containing a spring-loaded slider 13 with an inclined groove 14, and a horizontal hole 15, in which the cutter is tubular in shape 16.

 The blade 17 also has a blind vertical hole at the end, containing a spring-loaded slider 18 with an inclined groove 19, and a horizontal hole 20, in which a cutter of tubular shape 21 is located with the possibility of its extension to the well wall.

 The blade 22 also has a blind vertical hole 23 at its end, containing a spring-loaded slider 24 with an inclined groove 25, and a horizontal hole 26, in which the tubular cutter 27 is located with the possibility of its extension to the outer surface of the core at the time of completion of drilling and lifting of the projectile at the wellhead . The initial position of the slider is fixed by electric welding 28. To prevent clogging of the holes of the sliders with fragments of rock, the internal cavities of the cutters 16, 21 and 27 are closed with a rubber hole 29.

 In the presented embodiment, the drill head may have eight blades of different types of functional type 2, 3, 17 and 22. Their fastening is carried out by bolts 30, which are electrically welded to the blade bodies from turning.

 The supply of flushing fluid is carried out in the gap between the core receiving pipe (not shown in FIG.) And the burglar case, one stream, and another stream between the blades 31 of the case.

 The peripheral cutter 9 is insulated with a soft steel jumper 32, which protects it and the column from mutual damage in the transport position of the bit. During drilling, it is abraded, while the strength of the cutting edge in its nest is maintained, and the nominal size of the diameter of the well is provided by the calibration cutter 21. The inner surfaces of the housing 1 and blades 2 are reinforced with diamond chips 33. The housing is reused.

 Features of the proposed burgolovki following. According to the model, approximately 2/3 of the cuttings together with the liquid are removed through the internal cavity of the tubular cutters 8 and 9, designed for rough annular drilling of the bottom of the well, which are almost completely worn out during drilling, with the same contact area between the cutter and the rock being better cooled down.

 The principle of operation of devices for automatically extending calibration cutters is based on the fact that, as the blades 3 and 17 are actuated, the slightly springy sliders 13 and 21 do not wear out, but move from bottom to top under the action of the bottomhole reaction force, pushing the cutters 16 and 19 with their inclined grooves. respectively, towards the core and to the wall of the well, as they are erased.

 Tubular cutters improve all drilling performance by 50-60%.

Literature
1. I.K. Maslennikov, G.I. Matveev. Tool for drilling wells, M. Nedra, 1981, p. 263, Fig. 177a.

 2. I.K. Maslennikov et al. Tool for drilling wells, M. Nedra, 1981, p. 263, fig. 177b.

Claims (1)

1 1. A drill head, including a housing, interchangeable interchangeable blades with internal bores and grooves for their stop, characterized in that one of the blades is made with cutters for rough annular drilling of the bottom of the well, and the other, respectively, for calibrating the wall of the well, core and its cutting .2 2. The head according to claim 1, characterized in that the blade cutters are made of carbide material and have a tubular shape, and their holes are in communication with the annulus.2 3. The head according to claim 1, characterized in that the cutters for roughing koltsovye drilling of the bottom of the well are pressed into the body of the blade, isolated with a soft jumper with the possibility of preventing them from touching the wall of the well in the transport position. 2 4. The head according to claim 1, characterized in that one of the blades is made with a vertical hole in which a spring-loaded compression spring is installed a slider with an inclined groove, and with a horizontal hole in which the cutter is located with the possibility of its automatic extension to the wall of the well.2 5. Head according to claim 1, characterized in that the second blade is made with a vertical hole in which a slider spring loaded with a compression spring is installed with an inclined groove, and a horizontal hole in which the cutter is located with the possibility of its automatic extension to the outer surface of the core.2 6. The head according to claim 1, characterized in that the third blade is made with a vertical a hole in which a slider spring loaded with a compression spring is installed with an inclined groove, and a horizontal hole in which the cutter is located with the possibility of its automatic extension to the outer surface of the core in m The moment of completion of drilling and the beginning of the lifting of a core sampling shell at the wellhead.

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