SU1314017A1 - Method and apparatus for isolating absorption zones - Google Patents

Abstract

The invention relates to the oil and gas industry and improves the quality of the insulation works in the rear, by ensuring reliable contact of the elastic shell (EO) with the rock. The device includes a perforated pipe 1, couplings 2, 3, and a shoe 5. On the outer surface of the pipe 1, two mesh EO 8s are concentrically placed. 9. The dimensions of the EO 9 cells are smaller than those of the EO 8. For carrying out the method, the column is descended drill pipe (CW) 4 with the overlap; knot them. Then open the radial channels 13 of the pipe 1 and pump the cement mortar into the drill pipe. The solution fills the EO 8 and straightens it. Then it falls between EO 8 and 9. The liquid fraction of the solution is filtered beyond 30 8 through the EO 9 cells. The remaining cement will press the EO 8 to the walls of the well. This ensures the repetition of EO 9 trunk nerves. Then, the plug-in mixture with filler in EO 8 is injected. After waiting for the cement to harden, rotate CBT 4 to the right, they are disconnected. Next KBT raise to the surface and continue drilling. 2 sec. n. f-ly, 3 ill. "(L oo 4 O -CH fpue. J

Description

eleven

The invention relates to the oil and gas industry, in particular to the drilling of wells, and is intended to eliminate the absorption of washing liquid.

The purpose of the invention is to improve the quality of the insulation works by ensuring reliable contact of the elastic shell with the rock,

FIG. 1 shows the device in the transport position, longitudinal section; in fig. 2 the same, in the position of the end of the process of isolating the absorption zone, the longitudinal section in FIG. 3 shows the node I in FIG. 2

The essence of the method is as follows.

The drill pipe is piped down with an overlapping unit, the plugging mixture with filler is injected into the elastic casing of the blocking unit, the pipe string is disconnected with its subsequent lifting and further drilling is carried out before injection of the plugging mixture with filler subsequent filtering it outside the elastic shell to press it against the borehole wall.

The device consists of a perforated pipe 1, the upper and lower parts of which end with locking sleeves 2 and 3 for connecting the drill pipe string 4 and the shoe 5 to the device. In addition, centering lights 6 and 7 are placed on the locking sleeves 2 and 3. Outside the pipe 1 elastic mesh shells are located: the main 8 and concentrically of its outer surface are additional 9, attached from the bottom and top to the pipe 1 by clamps 10. For fixing the mesh elastic shells 8 and 9 on the perforated pipe 1 when the device is lowered into the well RAT elastic ring 11, .izgotovl e & Ie, for example, of rubber. Inside the perforated coarse 1 in its lower part is placed a sealed bushing - valve 12, having a through axial channel. When lowering the device, the sleeve 12 overlaps the radial holes 13 in the pipe 1. In order to eliminate spontaneous displacement of the sleeve 12 and the opening of the holes 13, the sleeve 12 is fixed with a shear pin 14. At the same time, the dimensions of the cells of the additional mesh shell 9 are smaller than the OS172 cells

new mesh elastic sheath 8.

The device works as follows.

5 After lowering the device on the drill pipe string to the required depth and feeling the artificial bottom (packer-plug or cement bridge, install; 4th below the sole

About the absorbing horizon), a ball 15 is thrown into the drill pipes, which sits in the saddle of the sleeve 12, blocking the axial channel in it. Under the action of the pressure drop that occurs when fluid is pumped into the drill pipe, the sleeve 12 is displaced downward, cutting off the pin 14, the radial holes 13 are opened, and the cement slurry is pumped into the drill pipes in the calculated amount, the output through these holes, fills the main elastic sheath 8, which under the action of the cement mortar first straightens 5

c and then stretched radially. Cement mortar, the passage through the cells of the main shell 8, falls into the space between the shells 8 and 9, stretching

In this case, the additional mesh elastic sheath 9. The liquid fraction of the cement slurry is filtered through the apertures of the additional sheath 9, and the remaining pressure cement 35 em shells 8 to the walls of the well, which ensures that the sheath 9 repeats the unevenness of the wellbore. Then a certain amount of cement solution is filled with a filler,

0 which is bumped with buffer fluid also in the calculated volume.

After the RFQ, rotating the pipe string to the right, disconnect it from the lock S coupling 2 of the device and remove the tool to the surface.

Then the chisel is lowered to drill the cement bridge, after which the dredging is continued to the design mark “0”.

Claims (2)

Invention Formula A method of isolating the absorption zones 5 of the washing liquid, comprising descending the drill pipe string with the overlapping unit; injecting the grouting mixture with filler into the elastic sheath of the overlapping unit. waiting for cement to harden, detaching the pipe string with their subsequent lifting and further drilling, characterized in that, in order to improve the quality of the insulation work by ensuring reliable contact of the elastic shell with the rock, prior to injection of the plugging mixture with the filler into it, the injection is performed cement, followed by filtering it beyond the elastic shell to press it against the walls of the well. 2. A device for isolating absorption zones, comprising a perforated tube, on the outer surface of which the main mesh elastic shell, locking collar and shoe is placed, characterized in that it is provided with an additional mesh elastic shell that is arranged concentrically with the outer surface of the main mesh elastic shell, and the dimensions of its cells are smaller than those of the main mesh elastic sheath. I fie. 2 Editor E. Kopcha Compiled by E. Molchanova Tehred L. Oliynyk. Proofreader N.Korol Order 2189/33 Circulation 533 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 fig.Z