RU2536600C1 - Drill bit flushing assembly - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: drill bit flushing assembly comprises body with channel and seat with circular groove and adapter with seal fitted in said seat and split lock ring with retainer arranged therein. Adapter has stepped outer surface. Split retainer ring is provided with rigidly connected plates made of material with shape memory and arranged at retainer ring lower end and shaped to arcs interacting with outer surface of adapter lower step at compression of lock ring.

EFFECT: simplified assembly/disassembly, improved hydrodynamics, higher reliability and efficiency.

3 cl, 4 dwg

Description

The invention relates to a rock cutting tool, mainly of a hydromonitor type, namely to their washing units.

A well-known flushing unit of a drill bit, comprising a housing with a channel for supplying a cleaning agent, a socket for a nozzle and an annular groove exceeding the double thickness of the retaining split ring, the ends of which are made in the form of a thorn-groove connection, and a sealing seal located between the bottom of the socket and the end of the nozzle ring (see ed. St. USSR No. 1148956, class E21B 10/18, 1985)

The disadvantage of this flushing unit is its low reliability associated with the possibility of erosion of the end sections of the retaining ring by the reflected flow of washing fluid and an increase in radially compressive forces acting on the retaining ring and squeezing it out of the socket due to the increased height of the annular groove.

The closest to the proposed technical essence and the achieved result is a flushing unit of the drill bit, comprising a housing with a channel and a socket made with an annular bore, and a nozzle with a sealing element and a snap ring with a retainer located in the annular bore of the socket (see ed. St. USSR No. 1601310, class E21B 10/18, 1990)

This flushing unit has a sufficiently high reliability due to the use of a latch in the form of a protrusion on the upper end of the retaining ring, which prevents extrusion of the nozzle from the housing socket.

Its disadvantages include the relatively high complexity of installation and dismantling, because To install the retaining ring, it is necessary to deform the sealing element by the size of the collar of the retaining ring. Another disadvantage of the known device is its hydraulic imperfection associated with the formation of a free cavity between the end of the nozzle and the bottom of the socket. This, with strong pressure drops in the nozzle, can lead to erosion of the sealing ring located in this cavity and, as a result, to depressurization of the flushing unit.

In connection with the above technical result of the invention is to simplify the installation and dismantling of the washing device and increase its efficiency by improving hydraulic perfection.

The specified technical result is achieved by the fact that in the flushing unit of the drill bit containing a body with a channel and a socket made with an annular bore, and a nozzle with a sealing element installed in the socket and a snap split ring with a retainer located in the annular bore of the socket, according to the invention, the nozzle is made with a stepped outer surface, and a snap split ring equipped with plates rigidly connected to it, made of material with shape memory, placed on the bottom end of the stopper th ring and made arcuate in plan with the ends cooperating with the outer surface of the lower stage compression nozzle retaining ring.

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

- the plates are placed at the end of the retaining ring along a chord located perpendicular to the axis of symmetry of the ring;

- the lower stage of the nozzle is made with an annular groove on the outer surface, while the arcuate ends of the plates in the working position are placed in the annular groove of the lower stage of the nozzle.

This embodiment of the washing unit allows, while improving the hydrodynamic characteristics of the washing unit and maintaining the high reliability of its operation, to simplify its installation and dismantling.

Figure 1 shows a General view of the washing unit in the working position in longitudinal section; figure 2 is a view of the washing unit from the side of the output end; figure 3 and 4 of the plate retaining ring, respectively, in the initial and working position.

The washing unit contains a housing 1 (Fig. 1) with a channel 2 for supplying a cleaning agent, made with a socket 3 for a nozzle 4 and an annular bore 5 for a snap split ring 6, a sealing element 7 and a latch 8. The nozzle 4 is made with a stepped outer surface, and the snap split ring 6 is provided with plates 9 rigidly connected to it, made of a shape memory material and placed on the end of the snap ring 6 along a chord perpendicular to its axis of symmetry. The plates 9 are placed on its lower end of the retaining ring 6 and connected to it in any known manner, for example, by soldering, spot welding, mechanical method, etc. The plates 9 are made in plan with arcuate ends 10 interacting in the working position with the outer surface of the lower stage 12 of the nozzle 4 in the event of forces compressing the retaining ring 6. The lower stage 12 of the nozzle 4 is made with an annular groove 11 on the outer surface for placement in them arcuate ends 10 plates 9.

The installation of the washing unit is as follows. In the socket 3, the sealing element 7 and the nozzle 4 are installed. After that, the retaining ring 6 is compressed, installed in the annular bore 5 of the socket 3 and secured against radial compression by the latch 8. In the initial position, the plates 9 have the shape shown in figure 3, and they do not interfere with compression of the snap split ring 6, because their free ends 10 do not contact the outer surface of the nozzle 4. After installing the retaining ring 6, the plates 9 are heated to a predetermined temperature, which is determined in laboratory conditions, and they take the form shown in figure 4. Moreover, the plates 9 in the working position have a length - L, greater than in the initial position - I, and their free ends come into contact with their arcuate ends and do not allow the retaining ring 6 to compress. To remove the ring 6, the plates 9 are heated to the initial temperature at which they occupy the initial shortened zigzag shape and do not interfere with the compression of the retaining ring 6, and therefore, its removal to replace the worn elements of the washing unit.

The application of the proposed site simplifies its installation and dismantling, improves the hydrodynamics of the flushing unit and maintains the reliability of its operation, thereby increasing the overall performance of the bit.

Claims (3)

1. The flushing unit of the drill bit, comprising a housing with a channel and a socket made with an annular bore, and a nozzle with a sealing element installed in the socket and a snap split ring with a retainer located in the ring bore of the socket, characterized in that the nozzle is made with a stepped outer surface, and the retaining split ring is equipped with rigidly connected plates of material with shape memory located on the lower end of the retaining ring and made in plan with arched ends, the interaction stvuyuschimi with the outer surface of the lower stage compression nozzle retaining ring. 2. The flushing unit of the drill bit according to claim 1, characterized in that the plates are placed on the end of the retaining ring along a chord located perpendicular to the axis of symmetry of the ring. 3. The drilling unit of the drill bit according to claim 1, characterized in that the lower stage of the nozzle is made with an annular groove on the outer surface, while the arcuate ends of the plates are placed in the working position in the annular groove of the lower stage of the nozzle.

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