SU1245704A1 - Apparatus for determining deformation properties and strain of rock body - Google Patents

Description

The invention relates to mining and is intended to study the stress state and the deformation properties of an array of rocks.

The purpose of the invention is to improve the accuracy of measurements in wells of conventional quality by directly measuring the deformations of the walls of the well under the action of high pressure developed directly by the device.

FIG. 1 shows the proposed device, placed in the well of normal quality; in fig. 2 shows section A-A in FIG. one; in fig. 3 shows the node I in FIG. 2 (in working position); in fig. 4 shows a section BB in FIG. 2

The device consists of a body made in the form of a figured rod, removable punches 2 installed on it, divided lengthwise into sections 3, and elastic measuring cameras 4, arranged in cavities formed by longitudinal grooves in body 1 and punches 2 At the same time, the ends of chambers 4 are sealed by fittings 5 in casing 6 rigidly fastened to housing 1. In housing 1, probes 7 and control probes 8 are mounted, the integral part of which is ferromagnets

Nitro sensor core 9 linear displacements.

The device works as follows.

The device is installed at a predetermined distance from the wellhead, working fluid is supplied through chambers 5 into chambers 4, which, increasing in volume, tightly press sections 3 to the borehole walls, after which the pressure in chambers 4 is raised to a level of 3-4 MPa in which the roughness and irregularities of the borehole wall are destroyed by the surfaces of the plungers 2, providing contact over the entire area of the sections 3, and zero counting is taken from the linear displacement sensors. Then, if the task of estimating the change in natural stress is solved, the hydraulic system is sealed and the movement of the probes 7 is monitored according to the sensor 9 for two to three days. If the deformation characteristics of the array are determined (deformation modulus, Punch coefficient), then in chambers 4 pressure is raised to the maximum possible for a given rock or device modification, fixing the displacement of the borehole walls according to the sensors 9, as well as the pressure gauge and the change in chamber volume 4, and using these parameters to determine.

BB

H

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h

FIG.

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Claims (1)

DEVICE FOR DETERMINING DEFORMATION PROPERTIES AND STRESSES OF ROCK MASS, including a body in the form of a curved rod with longitudinal grooves with removable sectional punches mounted on it with longitudinal grooves forming cavity with longitudinal grooves on the housing cavity, in which the ends are sealed fittings installed in cages rigidly connected to the housing, characterized in that, in order to increase the accuracy of measurements by direct measurement of deformations, it is equipped with a spring with the test probes, spring-loaded test probes and linear displacement sensors, the longitudinal grooves of the punches are double and form double symmetrically located cavities with the body, the spring-loaded probes are installed between the symmetric cavities with the possibility of joint radial movement with the punches, the control probes are placed between the punches with the possibility of radial movement, and linear displacement sensors consist of moving and fixed parts, while the moving part is connected to the probes and control probes, and fixed connected to the housing. SU „1245704 Figure 1