RU2163661C2 - Installation to pump fluid into pool - Google Patents

Abstract

FIELD: oil industry. SUBSTANCE: invention is related to oil and gas producing industry, to equipment designed to flood productive pools, in particular. Installation includes injection hole, submersible pump with electric motor, tubing string and packer installed above pool. Electric motor is positioned above well-head and is linked with the aid of shaft to submersible pump via stuffing-box seal. Inlet hole of pump communicates with water conduit, its outlet hole communicates with tubing string space. Tubing string is perforated in its lower part and rests against face. It is mounted for sliding through packer. Upper part of tubing string has releasable movable joint of plunger-cylinder type. EFFECT: simple, reliable and safe pumping of fluid into pool. 1 dwg

Description

 The invention relates to the oil and gas industry, and in particular to installations for flooding productive formations.

 Known installation [see Reference book on oil production. / Ed. Gimatudinova Sh. K., M .: Nedra, 1974], which includes a cluster pump station, a pressure pipeline and injection wells.

 Its disadvantage is the presence of an extensive network of pipelines operating under injection pressure (10.0-15.0 MPa), as well as the same, without taking into account the individual characteristics of the well, fluid injection pressure.

 Closest to the proposed one is an installation containing an individual submersible electric centrifugal pump, placed in a pit drilled near the injection well, into which injection water is supplied at low (1-2 MPa) pressure [see Handbook "Oilfield Equipment" ./ Ed. E.I. Bukhalenko, Moscow: Nedra, 1990].

 The pump, in turn, pumps this fluid into the injection well with the required pressure and flow rate. At high injection pressures, the injection well may be equipped with a packer.

 The disadvantage of the installation is its complexity due to the need to drill a pit, insufficient reliability due to the immersion of the electric motor in the fluid, increased danger due to the presence of a high-pressure pipeline between the pit and the well outside the well.

 The aim of the invention is the creation of a simpler, reliable and safe installation for pumping fluid into the reservoir.

 This goal is achieved by the fact that in the described installation for pumping fluid into the formation, including an injection well, a submersible centrifugal pump with an electric motor, a tubing string (tubing) and a packer installed above the reservoir, the electric motor is installed above the wellhead and connected by a shaft through the stuffing box a seal with a submersible centrifugal pump installed in the upper part of the injection well, with the pump inlet connected to the water conduit and the outlet to the cavity of the tubing string, which passes um slidably through the packer, resting on the bottom hole is perforated in the packer portion is at the top of the releasable connection type movable plunzher- cylinder.

 The drawing shows a diagram of an example installation.

 It contains an injection well 1 with a formation 2, at the mouth of which an electric motor 3 is installed, a shaft 4 of which is connected to a submersible centrifugal pump 6 through an oil seal 5. The pump inlet 7 is connected to a water conduit through a tap 8 (not shown in the figure).

 The pump outlet with a pipe 9 is connected to a plunger 10, which is inserted into the cylinder 11 mounted on the tubing string 12. The tubing string passes through the packer 13, where tightness and sliding are also ensured by the plunger-cylinder connection. The lower, under-packer part of the tubing string 12 is perforated with holes 14 and rested with the end in the face 15.

 The installation works as follows.

 Water from the water conduit enters the well 1 through the valve 8 through the inlet 7 is sucked in by a centrifugal pump 6 and is pumped at a pressure of 15-25 MPa through the pipe 9 with the connection of the plunger-cylinder (10.11) and tubing 12 with holes 14 into the area under the packer 13, from where it enters reservoir 2.

 In this case, only the under-packer zone is exposed to high pressure. Injection pressure and pump capacity are selected based on the characteristics of the formation in a particular well. The plunger-cylinder connection eliminates the possibility of tensile loads on the centrifugal pump during operation and facilitates assembly of the unit.

 The movable connection of the packer with the tubing frees it from variable axial loads, and also allows the tubing to be replaced without removing the packer.

 The location of the electric motor outside the well eliminates its premature failure due to loss of tightness by itself or by an electric cable.

 If the pressure in the water conduit is low (1.2-2 MPa), the liquid from the water conduit can also flow directly into the well cavity and then is sucked in from there by the pump.

 If water enters the well from a high-pressure water conduit (12-15 MPa), then the process is carried out only according to the above scheme.

 Thus, the proposed installation is simpler due to the absence of a pit, more reliable due to the placement of the electric motor outside the well, as well as the use of a plunger-cylinder connection and a packer with the possibility of sliding. In addition, due to the placement of the pump directly in the well, high pressure pipelines are eliminated, which increases the safety of the installation.

Claims (1)

 Installation for injecting fluid into the formation, including an injection well, a submersible pump with an electric motor, a string of tubing and a packer installed above the formation, characterized in that the electric motor is installed above the wellhead and connected by a shaft through an stuffing box with a submersible pump, the inlet of which communicated with the water conduit, and the outlet - with the cavity of the tubing, and the pipe string is perforated in the lower part, rested on the bottom, passes with the possibility of sliding through the packer and them There is a detachable movable connection of the plunger-cylinder type in the upper part.