EP0429649A1 - Drilling installation - Google Patents

Abstract

A drilling installation comprises an external tube (1) provided with teeth (10) on its end-face part, an internal tube (2) and a removable sectional drilling bit (crown) (4, 5) consisting of a casing (4) and of sectors (5). The sectors (5) are provided with teeth (11) for interaction with the teeth (10) of the external tube (1). The teeth (11) are oriented along a circumference in relation to the axis of the drilling installation and are made of a material whose hardness is lower than that of the material of the teeth (10). The external surface (3) of the internal tube (2) is provided with radial protrusions (16) mounted between the sectors (5) with the possibility of contacting by their lateral surface (17) with the lateral surface (18) of the sectors (5) of the removable bit (crown) (4, 5).

Description

Technical field

The invention relates to mining technology, particularly drilling equipment. Most successfully, the invention can be used in mining technology for core drilling by installing the rock destruction tool in the borehole or removing the rock destruction tool from the borehole without pulling the drill pipe.

Previous state of the art

In the drilling sets to which the present solution relates, the rock is drilled out during the rotary movement of the rock destruction tool. Here, the operational reliability of the drill kit depends on the reliability of the torque transmission from the drill string, the outer pipe, to the rock destruction tool. This reliability is guaranteed in different ways in different designs.

A drill set with an outer tube, an inner tube and a removable sector drill bit (US, A, 3692126) is known. An inner cone is machined on the outer tube face. In the working position of the drilling set, with the said cone turning out of the outer tube, conical surfaces of the removable sector drill bit are connected for the purpose of frictionally transmitting the torque when drilling from the outer pipe to the drill bit sectors. But said conical friction clutch does not work reliably and allows slip through, for example, when lubricant particles from the flushing liquid come onto the surface of the clutch, and when drilling in abrasive and cracked rock, when the torque of the friction of the drill bit on the rock is greater than the torque , which is transmitted from the conical friction clutch from the outer tube to the sector drill bit.

A drill set with an outer tube, a removable sector drill bit and an inner tube for spreading and fixing the sectors of the removable drill bit is also known. On the foreheads of the outer tube and the drill bit sectors are teeth on the inside, which lie in axial planes and interlock to transmit the torque from the outer tube to the sectors of the drill bit (US, A, 3603413). An orientation device is provided to ensure the orientation of the teeth of the sector drill bit with respect to the outer tubular teeth. The orientation device represents a set of cams in contact with one another, which are formed on the inner surface of the support plates of the drill bit sectors and on the inner surface of the outer tube in the lower part of this tube. Here, the tip of each cam on the surface of the support plates of the sector drill bit must lie in line with the center of the tooth on the face of the drill bit sector. This is a condition for the reliable engagement of the outer tube teeth in the teeth of the drill bit sectors

In the working position of the drilling set, the tips of the cams made on the surface of the supporting plates of the sector drill bit must lie in the gaps between the adjacent cams, which are made in the lower part of the outer tube. This arrangement of the cams of the orientation device ensures the desired position of the teeth of the sector drill bit in relation to the teeth of the outer tube, so that they later interlock when the inner tube is lowered into the lower limit position.

The orientation device described in the drill set complicates the design of the set.

In addition, errors in the manufacture of the orientation device cams during operation can cause "dead zones" to form at the tips of the contacting cams, which in turn can cause the cams to wedge in this position. The wedging can also be caused by dirt on the side surfaces of the cams with sludge, which makes the mutual movement of the cams difficult. The said wedging can result in the orientation device not responding, which results in an unreliable engagement of the teeth of the sector drill bit in the teeth of the outer tube, and ultimately the cause for breaks and failure of the drill set.

Disclosure of the invention

The invention has for its object to provide a drill set in which the teeth of the drill bit are designed such that the reliability of the engagement of the outer tube with the sectors of the drill bit is increased, which enables a simplification of the design of the drill set and an increase in its operational reliability .

This object is achieved according to the invention in the drill set, with an outer tube, on the end of which teeth are located in axial planes, an inner tube and a removable sector drill bit, the sectors of which have teeth for the interaction with the teeth of the outer tube, in that the teeth of the The core bit is oriented on the circumference of the circle with respect to the axis of the drill set and is made of a material whose hardness is less than the hardness of the material of the outer tube teeth.

The said design of the teeth of the sector drill bit ensures, when the nominal value (operating value) of the axial pressure of the drill set on the bottom of the borehole is reached, that a coupling is created, which is based on the cutting of the outer pipe teeth, which are made of a material with high hardness, into the teeth of the drill bit sectors , which are made of a material with a lower hardness than the hardness of the material of the outer tube teeth. This achieves a high adhesive value between the teeth of the outer pipe and the drill bit sectors, which enables the reliability of the connection of the outer pipe to the sector drill bits and thus the increased operational reliability of the drill bit to be increased. In addition, ensuring the reliability of the said connection gives the possibility of dispensing with the orientation device and thereby simplifying the construction of the drilling set.

It is appropriate that radial approaches are carried out on the outer surface of the inner tube, which between the sectors of the removable core bit and have the possibility of acting with their side surface on the side surface of the sectors of the removable core bit.

During the operation of the drill bit, the outer pipe teeth wear, which means that they penetrate to a lesser extent into the teeth of the sectors of the removable drill bit, which can cause the outer pipe teeth to slip over the teeth of the drill bit sectors, especially when drilling in heavily cracked rocks. In addition, slip through can occur at the beginning of the drilling process if the outer pipe teeth still cut incompletely into the teeth of the drill bit sector. The presence of said radial lugs on the outer surface of the inner tube makes it impossible to slip through and thereby increases the operational reliability of the drill set.

Brief description of the drawings

Fig. 1

im Schnitt die erfindungsgemäße Bohrgarnitur in Arbeitsstellung beim Bohren;

Fig.2

einen Abschnitt der Bohrgarnitur in Transportstellung beim Absenken der Sektorenbohrkrone;

Fig.3

einen Abschnitt der Bohrgarnitur in Transportstellung beim Ausbauen der Sektorenbohrkrone;

Fig.4

eine Ansicht in Richtung des Pfeils A in Fig.1;

Fig.5

eine Ansicht in Richtung des Pfeils B in Fig.3;

Fig.6

eine Ansicht in Richtung des Pfeils C in Fig.1 des Bohrkronensektors vor dem Bohren;

Fig.7

eine Ansicht in Richtung des Pfeils C in Fig.1 des Bohrkronensektors nach Beginn des Bohrvorgangs;

Fig.8

den Schnitt nach der Linie VIII-VIII in Fig.1, der die gegenseitige Stellung der radialen Ansätze des Innenrohrs und der Bohrkronensektoren erläutert;und

Fig.9

dasselbe wie in Fig.8 im Augenblick der Wechselwirkung zwischen den radialen Ansätzen des Innenrohrs und der Bohrkronensektoren.

The invention is explained in more detail, for example, with reference to the drawings. It shows

Fig. 1

on average the drilling set according to the invention in the working position when drilling;

Fig. 2

a section of the drill set in the transport position when lowering the sector drill bit;

Fig. 3

a section of the drill bit in the transport position when removing the sector drill bit;

Fig. 4

a view in the direction of arrow A in Figure 1;

Fig. 5

a view in the direction of arrow B in Figure 3;

Fig. 6

a view in the direction of arrow C in Figure 1 of the drill bit sector before drilling;

Fig. 7

a view in the direction of arrow C in Figure 1 of the drill bit sector after the start of drilling;

Fig. 8

the section along the line VIII-VIII in Fig.1, which explains the mutual position of the radial lugs of the inner tube and the drill bit sectors; and

Fig. 9

the same as in Fig. 8 at the moment of interaction between the radial approaches of the inner tube and the drill bit sectors.

Best embodiment of the invention

The drilling set contains an outer tube 1 (FIG. 1), inside which an inner tube 2 is arranged. A body 4 with sectors 5 is mounted on the outer surface 3 of the inner tube 2. The body 4 and the sectors 5 together form the sector drill bit 4, 5. The inner tube 2 can move in the axial direction of the drill set both together with the sector drill bit 4, 5 and also in its interior.

On the outer surface of the sectors 5 lugs 6 (Fig. 2, 3) are executed, and in the lower part of the outer tube i a recess 7 for fixing the lugs 6 of the sectors 5 is carried out in this recess in the working position of the drilling set.

On the inner surface of the sectors 5 shoulders 8 for fixing the inner tube 2 are carried out on these shoulders in the working position of the drilling set.

In the front part of the outer tube 1, longitudinal teeth 10 (FIG. 2) are embodied on the inner conical surface 9 (FIG. 1), which lie in axial planes. The sectors 5 of the removable drill bit 4, 5 have teeth 11 for the interaction with the teeth 10 of the outer tube 1. The teeth 11 of the sectors 5 are oriented on the circumference with respect to the longitudinal axis of the drill set (FIG. 6) and are made of a material whose hardness is less than the hardness of the material of the outer tube teeth.

The inner tube 2 is rigidly connected in the upper part to a suspension 12, which is equipped with locks 13 and a mushroom 14. The locks 13 are located in a recess 15 in the outer tube 1 and have the task of preventing the upward movement of the inner tube 2 when it is filled with the core material when the core is drilled out. In addition, the locks 13, which connect the inner tube 2 and the outer tube 1 to one another, serve to transmit the torque from the outer tube 1 to the inner tube 2.

In the lower part of the inner tube 2 3 radial approaches 16 (Fig.8, 9) are executed on its outer surface, which with the possibility between the sectors 5 of the drill bit 4, 5 lie in interaction on their side surfaces 17 with the side surfaces 18 of the sectors 5 of the drill bit 4, 5. The approaches 16 have the task of transmitting the torque to the sector drill bit 4, 5 from the rotating inner tube 2 when slipping through in the event of wear of the teeth 10 of the outer tube 1 relative to the teeth 11 of the sector bit 4, 5 to the sector bit 4, 5. In addition, the lugs 16 transmit the torque from the inner pipe 2 to the sector drill bit 4, 5 at the beginning of the drilling process if the teeth 10 of the outer pipe 1 have not yet been completely cut into the teeth 11 of the sectors 5 of the drill bit 4, 5 and when drilling in severely cracked Rocks.

On the outer surface 3 of the inner tube 2, an annular groove 19 is carried out in the lower part of this tube, and the body 4 of the sector drill bit 4, 5 is provided with elastic stops 20 which, when the inner tube 2 moves in the direction of the axis of the drill set inside the Sector drill bit 4, 5 can bend in one or in the other direction. During the upward movement of the inner tube 2 with respect to the sector drill bit 4, 5, the stops 20 snap into the annular groove 19 (FIG. 3) and in this way lead to the connection of the inner tube 2 with the sector drill bit 4, 5 for pulling the inner tube together and the drill bit through.

The plate part of the sectors 5 of the drill bit 4, 5 has elastic properties, as a result of which when the inner tube 2 moves inside the sector drill bit 4, 5, the sectors 5 are spread apart and come into the working position.

A core catch ring 21 is arranged in the lower part of the inner tube 2. The sectors 5 of the drill bit 4, 5 contribute to the End faces stone-destroying elements 22, which are designed, for example, as diamond-containing matrices.

The drill set works as follows.

Inside the outer tube 1, the inner tube 2 with the sector drill bit 4, 5 is lowered to the bottom of the borehole. Here, the inner tube 2 abuts against the elastic stops 20 of the body 4 of the sector drill bit 4, 5, abuts it and moves downwards together with it. In the lower limit position, the sectors 5 are spread apart thanks to their elastic properties, the stops 6 snap into the recess 7 of the outer tube 1 and the sector drill bit 4, 5 remains. Here, the inner tube 2 continues its downward movement inside the drill bit 4, 5, spreads the elastic stops 20 of the body 4 and the sectors 5 of the drill bit 4, 5. The movement of the inner tube 2 is limited by paragraphs 8 of the sectors 5, against which the inner tube abuts and stops.

When the inner tube 2 is at a standstill, the locks 13 of the suspension 12 of the inner tube 2 snap into the recess 15 of the outer tube 1. This ensures the possibility of transmitting the torque from the outer tube 1 to the inner tube 2. In this position, the drilling set is prepared for drilling.

When the drill set is placed on the bottom of the borehole, the longitudinal teeth 10 of the outer tube 1, which are made of a material with high hardness, cut into the circular teeth 11 of the sectors 5 of the drill bit, which are made of a softer material, and provide their connection. At the beginning of the drilling process, when the axial pressure of the drill string on the bottom of the borehole has not yet reached the nominal value (work value) and the teeth 10 of the outer tube 1 have not yet completely cut into the teeth 11 of the sector 5 of the drill bit 4, 5 a temporary slipping through of the outer tube 1 with respect to the sectors 5 of the drill bit 4, 5 is possible. Here, together with the outer tube 1, the inner tube 2 also rotates, which is coupled to the outer tube 1 by means of the locks 13. When turning of the inner tube 2, the projections 16 carried out on this tube come into contact with the sectors 5 of the drill bit 4, 5 and set them in rotation, whereby they transmit the torque to the drill bit from the inner tube 2 (FIG. 9). This eliminates the possibility of said slippage and increases the operational reliability of the drill set.

During the contact time of the sector drill bit 4, 5 with the inner tube 2, the axial pressure of the drill set on the bottom of the borehole reaches the nominal value (work value) and the teeth 10 of the outer tube 1 completely engage the teeth 11 of the sectors 5 of the drill bit 4, 5. The torque is now transmitted to the drill bit 4, 5 directly from the outer tube 1. This creates a coupling between the outer tube 1 and the sector drill bit 4, 5, which is based on the cutting of the teeth 10 of the outer tube, which are made of a material with high hardness, into the teeth 11 of the sector bit 4, 5, which are made of a material with lower hardness than the material of the teeth 10 of the outer tube 1 is based. Here, a high adhesive value is achieved between the teeth 10 and 11, which enables an increase in the reliability of the connection of the outer tube 1 to the sector drill bit 4, 5 and thus an increase in the operational reliability of the drill set.

Ensuring the reliable connection between the outer tube 1 and the sector drill bit 4, 5 gives the possibility of dispensing with the orientation device and thus simplifying the design of the drilling set. 7 explains the deformation of the teeth 11 of the sectors 5 of the drill bit 4, 5 when they interact with the teeth 10 of the outer tube 1 after the start of the drilling process.

The drill hole is drilled in this position of the drill set. The outer tube 1 is set in rotation. During drilling, the rock - the core - fills the inner tube 2. Here, a possible movement of the inner tube 2, which can be caused by the movement of the core inside the inner tube 2, is prevented by the locks 13, which are in the recess 15 on the outer tube 1 are fixed.

After the core has filled the inner tube 2, the rotation of the inner tube 2 caused by the outer tube 1 ceases and the drill set is raised with the aid of the core catch ring 21 to tear off the core from the bottom of the borehole. Thereafter, the inner tube 2, which fills the core, is pulled with the aid of a gripper device (not shown in the figures, in order not to complicate the drawings), which is coupled together with the catcher 14. Here, the upward movement of the inner tube 2 takes place first inside the sector drill bit 4, 5, which remains immobile during this process. When the annular groove 19 executed on the inner tube 2 contacts the elastic stops 20 of the body 4 of the sector drill bit 4, 5, the stops 20 snap into the groove 19 and produce a connection between the inner tube 2 and the sector bit bit 4, 5 for the purpose of pulling together.

Industrial applicability

Most successfully, the invention can be used in mining technology for core drilling by lowering the rock destruction tool into the borehole or removing this tool from the borehole without drilling the drill string.

Claims (2)

Drill set with an outer tube (1), on the end of which teeth (10) are located in axial planes, an inner tube (2) and a removable sector drill bit (4, 5), whose sectors (5) have teeth (11) for the interaction with have the teeth (10) of the outer tube (1), characterized in that the teeth (11) of the sectors (5) of the removable sector drill bit (4, 5) are oriented on the circumference with respect to the drill bit axis and are made of one material, whose hardness is less than the hardness of the material of the teeth (10) of the outer tube (1). Drilling set according to claim 1, characterized in that on the outer surface (3) of the inner tube (2) radial projections (16) are carried out, which between the sectors (5) of the removable sector drill bit (4, 5) with the possibility of interaction on it Side surfaces (17) with the side surface (18) of the sectors (5) of the removable sector drill bit (4, 5) lie.

Images