SU1553645A1 - Crown bit - Google Patents

Abstract

The invention relates to a rock cutting tool and is intended for drilling wells with coring. The goal is to increase the efficiency of the drill string by maintaining the influence of the second bare plane while at the same time eliminating the radial load on the cutter from the adjacent cutter. For this purpose, the incisors 9 and 11 of each row are installed with an angular displacement relative to the incisors 4 of an adjacent row and a larger diameter in the direction opposite to the direction of rotation of the crown. Core-forming incisors 4 and well-forming incisors 11 are installed with the possibility of interaction with the lateral surface of the rib 10 located between them. The incidence angle of the incisors is determined by a mathematical formula. The side surfaces of the fins 10 and 7 are installed with the possibility of contact with the ends of the cutters 4 and 9, respectively, this ensures their stable operation and prevents radial displacement, which increases the durability of the crown arms and provides better well calibration and equilibrium of the entire structure. 3 il.

Description

The invention relates to a rock-destroying tool, namely, drill bits with core sampling, and can be used in the mining industry.

The aim of the invention is to increase the efficiency of the drill bit by maintaining the influence of the second bare plane while eliminating the radial load on the cutter from the adjacent cutter.

FIG. 1 shows a drill crown, longitudinal section; in fig. 2 crown from the side of the working end; in fig. 3 - core cutter.

The drill crown contains a cylindrical body 1 with a connecting thread 2 and through grooves 3 at the end, in which core-forming cutters 4 are fixed, protruding beyond the inner diameter of the body 1 and performing the functions of a core mill. With this purpose I, the inner side surface of the cutters 4 is made with bevels 5, which in the vertical plane represent the figure in the form of an inverted cone 6. On the outer surface of the body 1 are ribs 7 with rigidly sakpenneHM and through cutters 9 whose width corresponds to the width grooves 8. Roll 10 can be performed both separately and together with rib 7. Well-cutter cutters 11 on rib 10 are installed in grooves 12 and protrude above outer surface of rib 10. Ribs 7 and 10 are installed in such a way that their inner side by the surface contacts, respectively, the outer lateral surface of core-forming cutters 4 and cutters 9. Cutters 4.9 and 11 are set in steps, with cutters 4 leading, and cutters 9 and 11 are offset relative to cutters 4 towards the connecting thread 2. In addition, cutters in each concentrate

The horizontal row is installed with angular mixing relative to each other in the direction opposite to the direction of rotation of the crown, the angle of displacement of is determined by the formula

o6 arc sin (-f- h 0.05 - 0.07),

TO,

0

five

0

five

where is 0

five

R 0, 05- -0.07

the thickness of the tool located on an adjacent concentric row of smaller diameter (for incarnations, 11 is the thickness of the tool 9);

the outer radius of the incisors with a thickness equal to B, i.e. these are the outer radius of the body I when determining the offset angle of the incisors 9 and the outer radius of the rib 7 for the incisors 11;

empirical values (for crowns with a diameter of up to 76 mm K 0.07; for crowns with a diameter of more than 112 mm, 05). The principle of operation of the crown is as follows. Under the action of axial load and torque, the incisors 4.9 and 11 penetrate into the rock and destroy it. Destroyed rock is carried by the flushing fluid to the surface.

The angular displacement of the incisors in this ratio creates favorable conditions for cooling the cutting edge of the incisors, cleaning the cuttings from sludge and maintaining the influence of the second bare plane. The installation of the ribs 7 and 10 with the possibility of contact with the ends (side edges) of the cutters 4 and 9, respectively, ensures their stable operation and prevents them from radial displacement. The same role is played by the lateral surface of the rib 10 for the well-forming cutters 11.

This is of particular importance for core and wellbore cutters 4 and 11, which are respectively subjected to radial loads from the core and from the side of the borehole walls. All this increases the durability of the crown arms. This also contributes to the fact that the hole-forming cutters 11 are thicker than the cutters JQ mi 1 and 9, which provides a better calibration of the borehole walls and equilibrium resistance of all weapons.

Claims (1)

Formula of invention) $ A drill crown, containing a body, ribs rigidly connected with it, and cutters fixed in concentric rows at the lower ends of the body and ribs 20 where B is in the radial direction and installed stepwise from core-forming R-cutters to bore-out cutters, characterized in that, , 05, .. in order to increase the efficiency of work- 25 0.07 - empirical values. You are drilling the crown by keeping the second bare surface flat with simultaneous elimination of the load on the cutter from the adjacent cutter, the cutters of each row are set with an angular displacement and take the cutters of the adjacent row of a larger range in the direction opposite to the rotation of the crown. the cutters are installed with the possibility of action from the lateral surface of the rib located between the same time and the magnitude of the angle of displacement o is determined from the expression about arcsln (- | - + 0.05 ... 0, the thickness of the tool located on a row of a smaller outer diameter radius of a range of less than a diameter; where B - R - 0.05, .. 0.07 - empirical values. you drill bit by maintaining the influence of the second bare plane while eliminating the radial load on the cutter from the adjacent cutter, the cutters of each row are set with an angular displacement relative to the cutters of the adjacent row of a larger diameter in the direction opposite to the direction of rotation of the crown, and the core-forming and well-forming the cutters are installed with the possibility of interaction with the lateral surface of the rib located between them; the angle of displacement of the incisors OЈ is determined from the expression about arcsln (- | - + 0.05 ... 0.07), empirical values. thickness of the tool located on a row of smaller diameter; outer radius p yes smaller diameter; FIG. 2 if H Fig.Z