SU1442638A1 - Method of cementing wells - Google Patents

Abstract

The invention relates to the oil and gas industry and is used in the construction of wells for various purposes. The goal is to increase the strength and sealing of cement stone. Buffer fluid (g) (process water or aqueous solution (P) of reagents), cement P, buffer fluid and a part of the injection well are pumped into the well through the filling tubing string. The hydraulic fluid is pumped with the largest pump flow, and the column is recommended to be rotated. Then the pump is stopped, the process is interrupted, and the flow velocity F is expected to decrease from the turbulent to the laminar regime. Mb A paired cessation of movement as a result of pressure equalization of the column of liquids in the pipe and eatrubny space. Observations are made to the output of the lower level of cement P to the shoe of the column of filling pipes, Then continue. The same pump is fed with pumps corresponding to the laminar flow G in the annular space. 2 Il. (L

Description

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The invention relates to the mining industry, and to oil and gas production, and is used in the construction of wells for various purposes, in particular in the cementing of wells with open, partially or completely cased trunks.

The purpose of the invention is to extract the volume of the selling liquid 7 with flow Q,.

If the works are carried out with full absorption, then after stopping the pump, the movement of air at the upper end of the column 1 of the pipe is observed. This movement is observed during the time of the liquid

the tightness and tightness of cement cement YU 3, 4 and 5 down the column of 1 pipe.

After the cessation of fluid movement in the well, indicating the equalization of pressures in the pipes and behind the pipes, proceed to the injection of the remainder of the calculated volume of the squeezing fluid.

FIG. 1 shows the scheme of the proposed method; in FIG. 2, the closing stage of the bridge installation.

In the well to the bottom of the cavern or the extended section of the barrel, a string of 1 pipe is lowered. For installation of the cement bridge, buffer fluid 2 (technical water or aqueous solution of reagents), cement mortar 3, buffer fluid 4 and part of the squeeze fluid 5 in volume V are pumped into dolonna 1. Purpose of the buffer fluid 2 is to release the bridge site from the flushing fluid 6 Therefore, the voucher fluid 5 in volume V is pumped with the highest pump flow. This tech15

bones 7 with feed

After the completion of punching, the pipe string is removed from the well, and after waiting for the cement solution to harden (RFP), work is continued in accordance with the geological technical equipment.

In the case of the use of cement mortars in a large volume, after the buffer fluid, cement mortar is pumped into the tubes in the volume of Uts, the injection is stopped and a decrease in the intensity of the flow of fluids in the well is expected to Q or equalization

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nological reception, as well as the use of pillars pressure buffer fluid shoe devices with lateral and cement mortar in the volume of

in pipes and columns of buffer and flushing fluids in the annulus, then the remainder of the calculated volume of cement mortar is pumped in, facilitates the release of the bridge installation site from the drilling fluid. In the process of pumping the volume of the UE, the column is recommended to be dispensed and rotated. After injection of the volume VP, the pump is stopped, and the column of pipes 1 with a shoe is held at the lower boundary of the future bridge (FIG. 1) in the base of the cavity. The process is interrupted and a decrease in the rate of flow of the fluid is expected.

ra, buffer and flow fluid with flow Q ,,

An example. Conditions: the nominal diameter of the open part of the trunk is 190.5 mm, in the intervals of 2568.5-2565.5 and 2565.5-2560.5 m of caverns with a diameter of 0.45 and over 0.60 m, respectively, in the well and receiving tanks of hydrogel magnetic pumps ( GGM) a solution of the specific weight of 1.22 g / cm, which is used for tool shaving for the bridge installation: TBPV pipes 114 mm 1690 m below and TBBV pipes 127 mm 880 m (internal volume of the tool 20.4 m) composition and volume of buffer oil the first and second portions, respectively .9 and 0.5 m of industrial water, the volume and specific gravity of the cement slurry. 5.65 m and 1.9 g / cm. The preset interval of cement bridge installation is 2460. If there is no catastrophic absorption in the well, t, e, partial or full circulation of the flushing fluid takes place, then after stopping the pump, the level of the outgoing wells in the gutters. At that time, when this level is equal to the pump flow corresponding to the laminar flow of fluids in the annulus Q n n4 of the pump (before starting work with the cementing unit, when the pipe string is lowered, fluid in the chute when the pump is fed) proceed to the injection of the remaining 7 with flow

After the completion of punching, the pipe string is removed from the well, and after waiting for the cement mortar (RFP) to harden, the works are continued in accordance with the geological and technical equipment.

In the case of the use of cement mortars in a large volume, after the buffer fluid, cement mortar is pumped into the tubes in the volume of Uts, the injection is stopped and the flow of fluids in the well decreases to Q or equalization

pressure columns of the buffer fluid and cement in the volume

ra, buffer and flow fluid with flow Q ,,

An example. Conditions: the nominal diameter of the open part of the trunk is 190.5 mm, in the intervals of 2568.5-2565.5 and 2565.5-2560.5 m of caverns with a diameter of 0.45 and over 0.60 m, respectively, in the well and receiving tanks of hydrogel magnetic pumps ( GGM) a solution of the specific weight of 1.22 g / cm, which is used for tool shaving for the bridge installation: TBPV pipes 114 mm 1690 m below and TBBV pipes 127 mm 880 m (internal volume of the tool 20.4 m) composition and volume of buffer oil the first and second portions, respectively .9 and 0.5 m of industrial water, the volume and specific gravity of the cement slurry. 5.65 m and 1.9 g / cm, the specified interval for the cement bridge installation is 24602568 m.

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To ensure the high quality of the cement bridge, a complete

the displacement of the GSH solution from the cavity, which is achieved by the intensive washing of the cavity of fresh technical water with the highest pump flow, rotation, rattling of the instrument and release of water through the side holes of the sub muffled from below.

In order to ensure a high-quality installation of the bridge, it is also responsible for the displacement of technical water from the cavern with cement mortar with a minimum flow rate, which ensures the laminar flow regime of liquids in the cavity. In the calculation of Rmitz, the smallest diameter of the cavity is obtained. Using the UCP value of 0.04 m / s and the borehole diameter of 0.45 m, we find: q, 0.8-0.04-0, 785-0.45 0.0051 or 5.1 l / s.

Supply within 5.1 l / s is ensured by the operation of the cementing unit at speed II (sleeves diameter 127 mm).

From the conditions of injection into the column of pipes, successively, buffer liquid, 5.3 m of water, 3 m of 1% aqueous solution of hydrochloric acid, 0.7 m of water, then 5.65 m of cement mortar, and after entering the parachute plug — 0.5 m of buffer water, it is calculated that the equality of the pressures in the pipes and behind the pipes is achieved after the injection of 8.8 m of a solution of HGM into the column, as a pressure fluid.

Prior to the commencement of work, the well is flushed, pumping into the pipes a solution of HGM at unit speed II (flow rate 5.1 l / s). At the same time, the height of the fluid flow in the troughs is noted.

Work is performed by flushing the well for 1 hour with technical water with a pump flow of 29 l / s, with simultaneous rotation and pacing of the tool, equipped with a bottom with side holes. For the second time, the well is washed with a solution of HGM after lifting, and the tool of the shoe part is above the cavity in order to displace water from the barrel above the cavity. In the cementing column agra

Gata is pumped successively listed liquid, bones. After the injection of 8.8 m of the GSH solution, the aggregate is stopped. The level of fluid in the gutters is monitored. As soon as the liquid level reaches the mark characterizing the flow of 5.1 l / s, the residue is pumped.

squeezing fluid in a volume of 10.8m. Until this volume is completely consumed, the level of liquid in the pumps does not exceed the specified level.

The tool is lifted from the well. Upon the expiration of the RPT time, the cement bridge is determined at a depth of 2476 m. The stone formed in the caverns is characterized by high strength.

Claims (1)

Invention Formula The method of cementing wells, including pumping buffer fluid, cement mortar, buffer and propellant fluids into the column, initially from the greatest and since the cement mortar into the annulus with the lowest pump flow corresponding to laminar fluid flow in the annulus, characterized by that, in order to increase the strength and tightness of the cement stone, after a buffered fluid or cement mortar, a portion of the cement mortar is pumped into the pipes liquid, the process is terminated and the flow velocity of the liquids from the turbulent regime is reduced to a laminar or complete cessation of motion as a result of pressure equalization of the column of fluids in the tubular and annular spaces until the lower level of the cement mortar reaches the shoe of the casting column, then continue pumping liquids to suckers corresponding to laminar flow fluids in the annulus. FIG. one FIG. 2