RU2286434C1 - Drill rod releasing device - Google Patents

Abstract

FIELD: mining, particularly for well drilling with the use of anticrash device for coring equipment.

SUBSTANCE: releasing device connected with rotatable drill pipe comprises body, engagement member fixedly secured to the body, sub and shaft with left-handed coarse thread fixed to the body by means of fixing members. The sub is secured to rotatable drill pipe and to shaft through left-handed coarse thread. Engagement member is made as engaging clutch provided with extension formed on lower end thereof and with segments located on upper clutch end. The sub has a number of segments arranged in area of engaging clutch cooperation with sub. The segments are spaced apart to provide engaging clutch insertion in gaps between the segments. Slots adapted to receive segments formed on upper engaging clutch end are created on widened shaft section.

EFFECT: increased strength and reliability, prevention of spontaneous rotatable drill pipe rods turning.

3 cl, 4 dwg

Description

The invention relates to the mining industry and is intended for use when drilling wells with an emergency device for a core projectile.

Known disconnector drill rods, consisting of a nipple and a clutch connected by a thread with a large pitch. Between the ends of the nipple and the coupling there is a bronze washer for self-sealing and holding the sludge in the space between the turns of the threads (see, for example, Kozlovsky EA and others. Manual of an engineer for drilling exploration wells. T.1, M., Nedra, 1984, p. 357).

The disadvantage of this disconnector is the unreliability of its operation. The practice of working with such disconnectors has shown the frequent spontaneous deployment of drill rods during tripping, when wedging rods in the well and sludge adapter, which are 20-25%.

The closest in technical essence and the achieved result is a drill rod disconnector having a right-hand thread for connecting to a core pipe and a left-hand disconnecting thread with a large pitch.

Inside the housing and the adapter, rectangular grooves are milled into which a latch is inserted, which is also rectangular in shape congruent to the shape of the grooves in the housing and the adapter. The latch is held in position by two leaf springs rigidly connected to the housing (see, for example, Vozdvizhensky B.I., Volkov S.A. Core drilling. M., Nedra, 1982, p. 348, Fig. 149b) .

The disadvantage of this disconnector is the ability to operate only from excess pressure of the flushing fluid. When working with air or gas-liquid cleaning agents (foams), which along with liquid cleaning agents are widely used when drilling wells, the disconnector does not work, since neither air nor foam is practically compressible and can not create the necessary force to cut the springs. In addition, the small transverse dimension of the retainer often does not withstand the short-term high torsional forces that occur when drilling fractured rocks, which leads to spontaneous deployment of drill pipes.

The technical effect expected from the use of the invention is to increase the strength of the node transmitting torque and axial force from the drill rods to the core drill, and to prevent spontaneous rotation of the rods from the core drill during tripping.

The specified technical effect is achieved by the fact that the drill rod disconnector connected to the core set consists of a housing, an engagement element, an adapter and fixing elements, is provided with a shaft with a left-hand thread of large pitch, rigidly connected to the housing by fixing elements made in the form of pins, an adapter, rigidly connected to the core set and a shaft with a left-hand thread of a large pitch, an engagement element, rigidly connected to the housing and made in the form of an engagement clutch, on the lower end of which there is a protrusion, and segments are made at the upper end, while at the point of interaction between the engagement clutch and the adapter, the latter has segments with a groove between them to allow the protrusion of the clutch to enter into it, and grooves with the possibility of segments entering on the upper end of the clutch, the protrusion on the lower end of the clutch and the groove in the adapter congruent in shape.

The invention is illustrated by drawings, in which Fig. 1 shows a General view of the disconnector in the working position in the context, Fig. 2 is a section along BB in Fig. 3 is a section along BB and in Fig. 4 is a section along AA in figure 1.

The disconnector consists of a housing 1 with a locking thread for connecting with drill rods, a shaft 2 with a left-hand thread of a large pitch, an adapter 3, an engagement clutch 4 and pins 5. The adapter 3, rigidly connected to the core set 6, has a groove 7 in the upper end, in which has a protrusion 8 located on the lower end of the clutch 4, in shape congruent to the groove 7 of the adapter 3 (see section aa in figure 4). The cross-sectional areas of the protrusion 8 of the clutch 4 and segments 9 of the adapter 3, formed when milling the groove 7, transmitting torque from the disconnector body 1 through the clutch 4 to the core set 6, are made equal. The absolute value of these areas is much larger than the cross-sectional area of the retainer of the prototype. As a result, the shear strength of the protrusion 8 and segments 9 exceeds the shear strength of the prototype retainer, and therefore, the disconnector is more reliable in operation.

At the upper end of the clutch 4, which is located in the housing 1 and is rigidly connected to it by a thread, there are segments 10 formed by milling a groove 11 (see section BB in Fig. 3), which enter the grooves only when eliminating the sticking of the column set 6 12 on the thickening of the shaft with the left thread 2 (see figure 2) after cutting the pins 5.

In the working position, the clutch 4 is in constant engagement with the adapter 3 due to the rigid connection of the shaft 2 with the housing 1 with pins 5, which eliminates the spontaneous turn of the drill rods from the disconnector body during tripping. Disconnecting the device from the core set is possible only if it is stuck and a certain axial force is applied to the rods, directed upward from the bottom of the well, calculated in each case in relation to the drilling conditions.

In order to protect the disconnector nodes from sludge getting into them in the adapter case 3, a groove 14 is made, in which the sealing element 13 is placed, which is pressed to the adapter 3 by the lower end of the disconnector case 1.

The disconnector operates as follows. When the core set 6 is stuck in the well, the drill rods are tensioned using the hydraulic system of the drilling rig. With sufficient axial force, the pins 5 are cut off, after which the protrusion 8 of the clutch 4 comes out of the groove 7 of the adapter 3, and the segments 10 of the clutch 4 enter the grooves 12 of the shaft with the left thread 2 for transmitting torque from the disconnector body 1 to the left-hand shaft 2. Then, without loosening the tension of the drill rods, give the right rotation and the shaft with the left thread 2 easily turns away from the adapter 3, freeing the entire drill string from the stuck core set.

Thus, the proposed technical solution of the disconnector has the following advantages over the known:

- significantly increased the bearing capacity of the node transmitting torque from the drill rods to the core set;

- eliminates the possibility of spontaneous reversal of the drill rods from the core set when performing hoisting operations;

- all structural elements of the disconnector are reliably protected from ingress of sludge;

- significantly increased reliability of the disconnector.

Claims (3)

1. Disconnector of drill rods connected to the core set and comprising a housing, an engagement element, an adapter and fixing elements, characterized in that it is provided with a shaft with a left-hand thread of large pitch, rigidly connected to the housing by fixing elements, the adapter is rigidly connected to the core set and the shaft with the left-hand thread of a large step, the engagement element is rigidly connected to the housing and is made in the form of an engagement clutch, on the lower end of which there is a protrusion, and segments are made on the upper end, while at the point of interaction I gearing clutch and the adapter last has segments with a groove between them to allow the clutch protrusion to enter into it, and grooves are made on the thickening of the shaft with the left-hand thread of a large pitch with the possibility of segments joining them on the upper end of the clutch. 2. The drill rod disconnector according to claim 1, characterized in that the protrusion on the lower end of the engagement clutch and the groove in the adapter are congruent in shape. 3. The drill rod disconnector according to claim 1, characterized in that the locking elements are made in the form of pins.

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