SU890324A1 - Oscillation source for well-logging - Google Patents

Description

I

The invention relates to mining and can be used in ore and coal mines to vibrate the rocks in order to redistribute the stresses in the pillars or to reduce their strength. %

Extended cylindrical devices are known that are fixed in drilled wells — wellbore deformers. They are fastened with the help of supports and spacers of the fixers, arching the borehole deformometers and supports G13.

Such an attachment serves to fix the deformometers and is not intended to transmit significant vibration forces.

A wellbore oscillation source used in seismic surveys is also known. It includes spacer elements in the form of longitudinal rods inserted into the well and compressed at the ends

two spring systems. The rods with a cross-sectional shape repeat the configuration of the well. In addition, there is a cylinder for compressed air attached between the rods. The device is introduced into the well, the balloon is filled with compressed air, its lateral dimensions increase, it tears the rods and presses them against the walls of the well. With the release of air

W from the cylinder of the spring system pull the rods and return them to the original. position, allowing the Kiesee to remove the device from the well. The vibration exciter is located on the surface of the earth.

15 and transmits the vibrations of the rods with the aid of accessory 2.

The drawbacks of the device are cumbersome, not allowing it to be used in cramped conditions of underground mines, as well as the complexity of the design, great weight. Spacer, being elastic. absorbs a significant proportion of vibrational energy. The closest to the present invention is a device for generating vibrations, including an anchor, which is connected with a pipe to spacer elements - hydraulic cylinders. They press special pads against the walls of the well, connecting the soil to the GZ anchor}. However, the known device is difficult, cumbersome, expensive, and its introduction into horizontal wells is hampered by the heavy weight and design features. To place the device in a horizontal well, special devices are required that are not provided for in it. The purpose of the invention is to increase the performance and simplify the design of a low-wave source of oscillations consisting of a vibration exciter and spread of loose elements. The goal is achieved by the fact that each spacer element is made of a wedge movably connected with the body of the vibration exciter of the downhole source of oscillations. Internal wedges adjoin the casing of the vibration exciter, installed with the possibility of axial movements, and external wedges, including the possibility of radial movements, are placed between the internal wedges and the borehole wall. The outer wedges are different in size from one another in the radial direction. This size increases from the spacer at the wellhead to the spacer at the bottom. Internal wedges are made with longitudinal tami. The rods facing the wellhead are threaded, fit into the holes of the supports mounted on the housing of the vibration exciter, and are tightened with nuts relative to the supports. The remaining pulls are connected to each other by the spring working for the thrust, and the spring stiffness decreases from the wellhead to the bottom. Due to this design of the oscillation source, after its installation in the well, the nuts that go into the hole supports, you can but wedge spacer elements and fix the source of oscillations in the well. Pa figs. depicts the source of oscillations introduced into the well and prepared for wedging, half of the strand; in fig. 2 - pop4. 4 shows a river section A-A in FIG. 1 (wedged source of vibrations). The vibration exciter 1 of the downhole source of oscillations carries guides 2 and elastic links 3 rigidly connected with it. In the guides 2 internal wedges 4 are installed with the possibility of axial movement, and links 3, made in the form of strips of spring steel, connect the case of vibration exciter I with external wedges 5 and ensure their radial mobility. Internal wedges 4, as well as external wedges 5, of a single spacer element equal in size. External wedges 5 different spacer elements have different sizes in the radial direction. At the outer wedges 5 closest to the wellhead, the thickness in the radial direction is minimal, at the outer wedges 5 of the next spacer it is larger and so on up to the spacer at the bottom of the hole J to which the thickness of the external wedges 5 is maximum. Therefore, in the initial position, the gap between the outer cylindrical surface of the outer wedges 5 and the borehole increases in the reverse order, i.e. from the bottom of the well to the mouth. The internal wedges of the four spacer elements closest to the bottom of the well have one thrust of 6, the remaining internal wedges each have two thrusts of six. The thrust 6, facing the wellhead, are threaded, fit into fixed supports 7 and carry nuts 8 and 9. The remaining rods 6 are interconnected by springs. 10. The springs are distinguished from each other by rigidity. The stiffness of the spring closest to the wellhead is maximum, the stiffness of the following springs is successively reduced, the stiffness of the spring closest to the bottom of the well is minimal. FIG. 1 and 2 three spacer elements along the length of vibration exciter 1 are shown with three pairs of wedges around the circumference in each spacer element. Both quantities may be different. The housing of the vibration exciter may be non-circular. The well source of oscillations works in the following way. It is inserted into the drilled well. Dp facilitating this operation can be used a grooved strip, enclosed bottom, reproducing the shape of the well and enter

into it along with a vibration exciter. By turning the nuts 8, the wellhead of the well 6 and the inner wedge 4 J closest to the wellhead are pulled in the direction. In the same direction, the remaining inner wedges 4 begin to move with their joints and springs. The outer wedges 5 are moved apart and until they come into contact with the borehole walls, the rotational force of the nuts 8 is minimal, since only the frictional forces of the inner wedges 4 are overcome. come in contact with the borehole walls. The wedge of this spacer is tightened. The rotational force of the nuts 8 increases, since the force of the springs closest to the tightened wedges is added to the friction forces of the open wedges (in Fig. 1 the right spring 10). Next, the wedge of the next spacer element (in Fig. 1, medium) is tightened, since now the gap between the outer surface of the outer wedges 5 and the borehole wall is minimal. Thereafter, the tightening force of the nuts 8 increases again, since the force of the spring of greater rigidity (in Fig. 1 of the left spring 10) is added to the friction forces of the remaining wedges. Finally, the wedge of the spacer closest to the wellhead is tightened. The nut 8 stops, the well source of oscillations is ready for operation. The motor of the vibration exciter is turned on, oscillations occur, transmitted through the rock spacers. Due to vibrations, wedge joints tend to loosen.

Consider the resulting forces, and we start with the spacer at the bottom of the well.

Since the outer wedge 5 does not have the possibility of axial movement, the wedge joint can be weakened only by moving the inner wedge 4 to the right. However, this is prevented by the force of the tension spring 10, which on the other side is pulled by the internal wedge 4 of the adjacent spacer element. But its wedge connection also cannot loosen, since in turn it is tightened to the left with a greater force of a more rigid stem. different. Krayn,

The spring closest to the wellhead, the most rigid and stretched with the greatest effort, is coupled with an extreme internal wedge 4, which is deprived of the possibility of axial movements during the operation of the vibration exciter, since its ha is fixed on support 7 by nut 8.

Thus, each internal

o wedge 4 is in the axial direction under the influence of two forces generated by the springs: a smaller force acts on the right, tending to weaken the wedge joint, and a larger force on the left

5 force, seeking to tighten it. Due to this, wedges are constantly tightened, despite the effects of vibrations.

To disassemble the wedge joints, after the work is completed, the nuts 8 are unscrewed and the nuts 9 are tightened. Thе ha 6 with thread and internal wedge 4 closest to the wellhead are pressed into the well, successively through the rods and wedges

S their spacer elements and weakened their connections. The spacers come to their original position, the source of oscillations can be removed from the well.

О When choosing the size of the well source, one should be guided by the vibration forces, technological capabilities of the drilling and vibrating equipment, the contact

J rock strength.

Choosing one or another tilt angle of wedges and spring stiffness can change the functions performed by them. If the angle is small, as shown in FIG. I, then

 the wedge joints are self-engaging and the force of the springs is only necessary to prevent the wedge joints from weakening from vibration. If the angle is larger, self-engaging does not occur and the springs must be such that their forces are sufficient to ensure the working position of the wedges and to perceive some component of the vibration force. In this Case, unlike the previous one, the Yutinov compounds possess compliance.

Claims (3)

The downhole source of vibration allows vibration to be applied to the rocks to redistribute the stresses in the pillars and eliminate dangerous dynamic manifestations of the rock pressure. This allows to significantly reduce the cost of explosives, increase the safety and productivity of miners, use the best mining technology. The invention The downhole source of oscillations, including the vibration exciter and spacer elements associated with it, for mounting in the well with the possibility of radial and axial movements relative to the latter, characterized in that, in order to increase productivity and simplify the design, the spacer element is designed as an internal, adjacent to the vibration exciter and external wedges, the internal wedge is installed with the possibility of axial displacements and is made with rods, and the external NII is installed with the possibility of radial displacements and is connected to the vibration exciter by elastic connections; the plugs of each spacer element are connected to each other by rods, the rigidity of which decreases from the end of the exciter facing the squamdane mouth, to the end facing the bottom of the well, and / or the nuts are fixed with nuts adjustment in the supports made on the end of the vibration exciter facing the wellhead, while the transverse size of the external wedges increases from the end of the vibration exciter facing the wellhead to the opposite end. Sources of information taken into account in the examination 1. Technique to control stresses and deformations in rocks. L., Science, 1978, p. 133-138. 2. Patent C11A-1p 3346066, 181-106, published. 1967. CL 3. US patent 3282371, 181-106, published. 1966 (prototype), class