RU2422613C1 - Ring bore bit - Google Patents

Abstract

FIELD: oil and gas production. ^ SUBSTANCE: ring bore bit of cutting type consists of case with connecting thread and is divided with flushing channels to sectors equipped with cutters. The cutters are reinforced with diamond-hard-alloy plates at negative front angles to end surface of well bottomhole. Replaceable diamond-hard-alloy plates are secured in cylinder slots with hold-down screws, which facilitates rearrangement of the diamond-hard-alloy plates and multiple usage of the bore bit. ^ EFFECT: minimum twice increased general service life of expensive tool compared to bore bit with soldered diamond-hard alloy plates. ^ 5 dwg

Description

The invention relates to crowns intended for drilling wells with coring for fractured and alternating in hardness rocks during the exploration of deposits for solid minerals and water.

A known metal-cutting tool is a face mill (RF patent for invention No. 2318635), in which reinforcing high-resistance plates are fixed mechanically.

Disadvantages: the fastening system of the cutting elements of the end mill is not suitable for round cylindrical inserts used to equip the annular drill bit, in addition, the mill can be used to process rock blocks, but not for drilling wells.

Known annular drill bit (RF patent for the invention No. 2359103), comprising a housing with a connecting thread, divided by washing channels into sectors, equipped with cutters that are reinforced with diamond carbide inserts and have negative rake angles in plan to the side inner surface of the cutting, adopted by us in as a prototype.

Disadvantage: the impossibility of restoring a worn crown to its nominal size, since all reinforcing diamond carbide inserts are fixed by soldering. This limits the use of the crown to one drilling cycle.

The objective of the invention is to increase the operating time of the annular drill bit by restoring it by rearrangement of diamond carbide inserts, fixed mechanically, which is achieved by the fact that the annular drill bit contains a housing with a connecting thread, divided by flushing channels into sectors that are equipped with cutters reinforced with diamond carbide inserts and having negative rake angles in plan to the lateral inner surface of the cutting, and the cutters are reinforced with replaceable diamond-TV carbide plates fixed in cylindrical grooves with cylindrical wedges with clamping screws.

The invention is illustrated in figures 1, 2, 3, 4, 5.

Figure 1 shows a front view of a cutting type annular drill bit with mechanical fastening of diamond carbide inserts with cylindrical wedges with clamping screws.

Figure 2 shows a fragment of a top view of a cutting type annular drill bit with mechanical fastening of diamond carbide inserts with cylindrical wedges with clamping screws.

Figure 3 presents the diamond carbide plate, a cylindrical groove and a cylindrical wedge in an orthogonal coordinate system (X, Y, Z).

Figure 4 presents a General view of the diamond carbide plate in conjunction with a cylindrical wedge.

Figure 5 presents the geometric parameters of the installation of diamond carbide inserts and a diagram of the forces on the cutting edge.

The annular drill bit of the cutting type comprises a housing 1 with a connecting thread 2, divided by flushing channels 3 into sectors 4, equipped with cutters 5 reinforced with diamond carbide inserts 6. In the housing 1 in a cylindrical groove 7 having a diameter equal to the diameter of the diamond carbide plate 6 , a cylindrical wedge 8 is located, which has a limited degree of freedom in movement along the X and Z axes, but capable of moving along the Y axis.

The diamond carbide insert 6 inserted into the cylindrical groove 7 abuts with its rear surface 9 against the end surface 10 of the cylindrical groove 7 and is pressed against it by the cutting force F and the axial force P _z . A cylindrical wedge 8, secured by a clamping screw 11 of diameter d, holds the diamond carbide plate 6 from moving along the Y axis. The clamping screw 11 holds the cylindrical wedge 8 from rotation.

The annular drill bit of the cutting type operates as follows.

During rotation transmitted from the drill rig (not shown), the crown, in contact with the bottom of the well, destroys it due to the fact that the cutters 5 reinforced with diamond carbide plates 6 installed with a negative rake angle β and trailing angle α cut through concentric overlapping channels. In the cutting process, only part of the circular annular edge of the diamond carbide plate 6 is involved, which is in contact with the rock, the wear of which leads to a change in the size of the tool. However, most of the circular annular edge, not participating in the cutting, remains sharp. The design after rearranging diamond carbide inserts allows you to use the crown repeatedly. This increases the total operating time of an expensive tool by at least two times, compared with a crown with soldered diamond carbide inserts, which achieves the objective of the invention.

Claims (1)

An annular drill bit containing a housing with a connecting thread, divided by flushing channels into sectors that are equipped with cutters reinforced with diamond carbide inserts and having negative rake angles in plan to the side inner surface of the cutting, characterized in that the cutters are reinforced with replaceable diamond carbide inserts, cylindrical wedges fixed in cylindrical grooves with clamping screws.

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