SU629324A1 - Method of securing boreholes - Google Patents

Description

one

The invention relates to a drilling technique and can be used when attaching deep wells to casing columns.

There is a known method of fastening a well, including descending into a cemented column of a removable casing r-3.

The disadvantage of this method lies in the difficulty of removing the removable column and the insufficient durability of the structure.

There is a method of mounting a well, which includes the descent into the cemented column of a removable casing pipe. Lonny and the introduction of a lubricating fluid for a removable casing p

However, this method reduces the forces of friction and mechanical wear of the casing, requires additional operations and special complex devices — when replacing a worn part.

The purpose of the invention is to simplify the replacement of a removable casing and ensure its durability.

This is achieved by the fact that the space behind the removable casing is hydraulically connected with the well stem and the lubricating fluid

served under pressure, determined by the formula

(ifrSCa) P | r,

where f is the pressure of the lubricating fluid, kg / cm;

N - the depth of the descent removable casing, cm}

V} the specific gravity of the lubricant additive and flushing fluid,

KG / CM7

R. pressure loss in the annular space, kg / cmg

The drawing shows a device for implementing the proposed method.

in the interstitial cemented column 1, a replaceable column 2 is lowered with centralizers 3 so that a gap is formed on the bottom end side, taking into account the elongation of the column own weight and temperature in the well. The annular space A with the annular space B, in which the drill string 4 is located, is hydraulically connected through the gap B.

Claims (1)

The annular space A is hermetically connected through the discharge line and the valve 5 with the mud pump 6, the metering pump 7 and the tank 8 with the lubricating fluid. As such Moryi fluids, various types of PAAD compatible with the industrial liquid used are used. Lubricating fluid can leak into the well in two ways. According to the first method, the liquid from the tank 8 is fed through the injection line with the valve 9 and the dosage beginning 7 with adjustable capacity from O. to 5 l / s, which forces it into the annular space A. At the same time, the valves 10, 11. and 12 are open, the rest are are closed. Mud pump B injects the solution into the well, as usual. . The second method does not require the installation of a metering pump 7, the PAAD solution is introduced into the annular space A using the main mud pump b and an ejector torus 13 installed on the line connecting the mud pump to the column 1. The amount of drilling mud supplied to the annular space A , regulate installation in the ejector replaceable nozzles. The main amount of the solution, technologically necessary for drilling of the well, enters the drill pipes, and a small part of the solution, limited by the size of the installed nozzle in the ejector, is sufficient to introduce lubricant into the annular space A, For the differential pressure across the ejector nozzle , PAAD from the tank 8 through the line with the valve 14 enters the ejector and then with a small part of the solution into the annular space A. When the valves 10, 15 16 and 9 are closed, the rest are open. yvayuschego effect on the treated surface must have a sufficient concentration of the additives in solution. the effect of the lubricating effect 8 of the proposed method is achieved due to the fact that the additives are introduced over the entire depth of the well, and only in the interval of descent (casing string. Lubricating additives can be introduced in a pure form in the required amount, at a full liter. ns. This is a laborious process of preparing a qualitative solution with lubricant 1 and additives on the tee. This process takes place automatically in the borehole, which is another advantage of the proposed method.; Dx1I enhancing the durability of the columns in addition introduction of a lubricating fluid, a removable column is rotated.The proposed method provides effective reduction of frictional forces between the columns and the drilling tool during work in the barrel due to the constant supply of lubricant to the annular space and improves the reliability and durability of the well as a whole. casing, monitoring the level of the solution in the wellbore and uniformly dosed injection of PAAD into the solution. Sticking and complications with removable casing and drill pipes are prevented. The invention method of mounting the well, including the descent into the cemented column of the removable casing and the introduction of a lubricating fluid behind the removable casing, is also so that, in order to simplify the replacement of the removable casing and increase its durability, the space behind the removable casing the column is hydraulically connected to the well bore, and the lubricating fluid is supplied under pressure determined by the fool (r 2VTf ", where P is the pressure of the lubricating fluid, kg / cm; H is the descent depth of the removable casing here, cm: fiH. —the specific gravities of the lubricant additive and flushing fluid, kg / ct, RP — pressure loss in the annular space, kg / cm. Sources of information taken into account during the examination: 1. Kiselman M. L. Wear and casing strings protection during deep drilling, M. Nedra, 1971, pp. 152. 2, Ozorenko, A. F. Adaptations for changing the current and daily columns., M., Nedra, 1971, p.