RU2465427C1 - Drilling bit bearing structure - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: drilling bit bearing structure includes inclined trunnion provided with axial lubrication supply channel and roller cutter installed on trunnion by means of locking bearing; at that, it is equipped with locking bearing unloading assembly made in the form of liquid wedge diaphragm arranged on lubrication movement way. As per the first version, liquid wedge diaphragm is formed with conical surface made on end section of trunnion and cylindrical surface of roller cutter cavity. As per the second version, liquid wedge diaphragm is formed with conical surface made on end section of internal surface of roller cutter and cylindrical surface of end section of trunnion.

EFFECT: increasing operating efficiency of locking bearing, bearing structure and bit as a whole.

4 cl, 5 dwg

Description

The invention relates to a rock cutting tool, and in particular to bearings of rolling cutter bits.

There is a known support of a cone bit containing a pin on which, using sliding and rolling bearings, one of which is a lock, a roller cone with working elements is installed (see the reference book “Drill bits” Paliy P.A. and Korneev K.E., M., Nedra, 1971, p. 175, fig. VI.29).

The disadvantages of this support of the bit include its quick failure due to the lack of lubrication of the bearings, which especially affects drilling during forced operation.

Also known is the support of a cone bit containing a paw with an inclined pin and a cone mounted on the pin using a sleeve bearing and a lock bearing (see Catalog of drill bits, VOLGABURMASH, 2003, p.13, Fig. 2).

In this bit, thanks to the use of a floating bearing, it was possible to increase the operability of the support. The negative sides of this design of the drill bit support include the insufficient bearing capacity of the sliding bearing at significant eccentric loads.

Closest to the proposed technical essence and the achieved result is the support of the cone bit, containing an inclined pin made with an axial channel for supplying lubricant, and a cone mounted on the pin using a locking bearing (see RF patent No. 2351740, class. ЕВВ 10/22 , 2009).

The disadvantages of this bit support are the leading output of the lock bearing compared to other bearings due to significant loads acting along the axis of the axle and perceived by the lock bearing.

In accordance with the stated technical result of the invention is to improve the operating efficiency of the support and the bit as a whole by improving the working conditions of the castle bearing.

The specified technical result is achieved in that the support of the cone bit containing the inclined pin made with an axial channel for supplying lubricant and the cone mounted on the pin using a lock bearing, according to the invention, it is equipped with an unloading unit for the lock bearing made in the form of a liquid wedge diaphragm placed in the path of lubrication.

The achievement of the technical result also contributes to the fact that

- the liquid wedge diaphragm is formed by a conical surface made on the end portion of the journal and the cylindrical surface of the cone cavity;

- the conical section of the trunnion is made in the form of a removable sleeve of material, the wear resistance of which is higher than that of the trunnion material;

- the liquid wedge diaphragm is formed by a conical surface made on the end portion with the inner surface of the cone and the cylindrical surface of the end portion of the spigot,

- the conical section of the cone is made in the form of a removable sleeve of material, the wear resistance of which is not lower than that of the cone material

This embodiment of the support of the bit allows you to unload the lock bearing from the loads acting along the axis of the journal.

The invention is illustrated by drawings, where in Fig.1 shows a General view of the support of the bit in the context, Fig.2-5 - embodiments of the support.

The support of the roller cone bit includes an inclined pin 2 made in one piece with the paw 1, and mounted on the pin 2 by means of a lock roller 5, the pin 4. The paw 1 and pin 2 are made with channels 3 for supplying lubricant from an oil-filled container (not shown). The support of the bit is equipped with a knot for unloading the lock bearing, made in the form of a liquid wedge diaphragm 6, placed on the path of passage of lubricant. The wedge diaphragm 6 is formed by a conical surface 7 made on the end portion of the journal 2 and a cylindrical surface 8 of the cone 4 cavity, forming an angle α between themselves. In this case, the conical section 7 of the pin 2 is made in the form of a removable sleeve 9 from a material whose wear resistance is higher than that of the material of the pin 2. The removable sleeve 9 can be made in the form of a stepped tip (see figure 2) or a hollow sleeve (see Fig. .four). The choice of the type of tip 9 is determined by the parameters of the drilling mode. At high loads acting along the axis of the pin 2, it is preferable to use the stepped sleeve shown in figure 2. In addition, the physicomechanical properties of the drilled rocks also affect the choice of tip type. Another embodiment of the wedge diaphragm 6 is the use of a wedge surface 10 on the inner surface of the cone 4 and a cylindrical surface 11 on the end portion of the pin 2. An embodiment of the conical portion of the cone 4 in the form of a removable sleeve 12 of a material with a wear resistance not lower than that of cone material 4. It is preferable for the manufacture of removable bushings to use material in the form of a hard alloy. A variant of the formation of the wedge diaphragm 6 is also possible by using wedge-shaped surfaces both on the pin 2 and on the inner surface of the cone 4 (not shown).

The principle of operation of the drill bit support is as follows. During drilling, the axial load is perceived by the supporting elements of the cone bit. Moreover, the load acting along the axis of the pin 2 is perceived by the locking bearing 5 and the liquid wedge diaphragm 6, and the radial load is then perceived by both the locking bearing and other supporting surfaces. When the lubricant is supplied through the channel 3 and passing it through the liquid wedge diaphragm 6, the resistance to the lubricant passage sharply increases and a liquid wedge appears, which prevents the cone 4 from moving towards the pin 2. The force arising from this from the hydraulic wedge will be directed towards the cone 4, which allows reduce the load on the lock bearing 5 and thereby increases its service life, and therefore the support as a whole.

Claims (4)

1. Support cone bit, containing an inclined pin made with an axial channel for supplying lubricant, and a cone mounted on the axle by means of a lock bearing, characterized in that it is equipped with an unloading unit of the lock bearing, made in the form of a liquid wedge diaphragm located on the path lubrication, and the liquid wedge diaphragm is formed by a conical surface made on the end portion of the journal and the cylindrical surface of the cone cavity. 2. Support cone bit according to claim 1, characterized in that the conical portion of the journal is made in the form of a removable sleeve of material, the wear resistance of which is higher than that of the journal. 3. The support of the cone bit, containing an inclined pin made with an axial channel for supplying lubricant, and a cone mounted on the pin using a lock bearing, characterized in that it is equipped with an unloading unit for the lock bearing, made in the form of a liquid wedge diaphragm located on the path lubrication, and the liquid wedge diaphragm is formed by a conical surface made on the end portion of the inner surface of the cone, and the cylindrical surface of the end portion of the journal. 4. Support cone bit according to claim 3, characterized in that the conical portion of the cone is made in the form of a removable sleeve of material, the wear resistance of which is not lower than that of the cone material.

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