RU2804087C1 - Device for dual completion - Google Patents

Abstract

FIELD: oilfield equipment.

SUBSTANCE: used as part of an assembly with an electric centrifugal pump for dual completion in low-pressure wells. A device for dual completion is claimed, characterized in that it consists of a shaft connected to an electric submersible pump (ESP) with a power cable with a cup packing, above which a double-circuit turbopump is located, connected to a tubing. At the same time, the double-circuit pump contains a perforated outer pipe of the outer contour and an impeller or an assembly of impellers mounted on bearings with the possibility of free rotation, located inside the perforated outer pipe, forming an inner contour and equipped with internal and external impellers. In the upper part of the turbopump there is a mixing chamber for connecting the fluid flows passing through the inner and outer circuits.

EFFECT: simplification of the device for dual completion due to the exclusion from the layout of the additional pump and associated surface equipment, including power consumption.

3 cl, 6 dwg

Description

The invention relates to oilfield equipment, and can be used as part of an assembly with an electric centrifugal pump for simultaneous and separate operation in wells with low reservoir pressure and uses the hydrodynamic energy of the ascending fluid flow created by the electric centrifugal pump in the sub-packer zone.

A device is known for simultaneous separate oil production from two formations (RU120704 U1), including a section of impellers, a receiving pipe for the flow of liquid from the lower formation into this section, a packer that isolates the layers, a telescopic connector placed on the pipe between the packer and an additional section of the pump . The pump impeller section is located in the main pump housing above the submersible motor. An electric centrifugal pump (ESP) is installed in the above-packer zone and communicates with the under-packer zone through the inlet pipe

A device is known for the simultaneous separate production of oil from two formations (RU73391 U1), including a packer, an additional centrifugal pump driven by one submersible electric motor for selecting part of the product and directing it through the radial outlet holes to receive the main pump. A prerequisite for operation is the need to first lower and install a support ring into the well to separate the above-packer and below-packer zones.

A device is known for simultaneous separate oil production from two formations (RU161063 U1, selected as a prototype), containing a barrel, a packer located with the possibility of separating the layers, a flow module, above which there is a receiving module of the upper pump, which with the flow module forms a single casing with permeable side walls.

A common disadvantage of the known devices is the complexity of the design associated with the need to use two pumps, each of which has its own drive and associated underground and surface equipment (for example, a pumping machine, sucker rods, wellhead electric motor).

The technical objective of the invention is to simplify the device for simultaneous oil production from two formations by eliminating the additional pump and associated surface equipment from the layout, including power consumption, and the unimpeded passage of reservoir gas from the sub-packer zone to prevent the dynamic level from being squeezed out by gas pressure in the sub-packer zone. The technical result of the invention is to simplify the device for simultaneous oil production from two formations. At the same time, the device's time between failures increases.

The technical result is achieved in a device for simultaneous oil production from two layers, consisting of, connected to an electric centrifugal pump (ESP) with a power cable, a barrel with a cup cuff, above which there is a double-circuit turbo pump connected to a tubing pipe (Tubing), while a double-circuit pump contains a perforated outer pipe of an external contour, and an impeller or impeller assembly mounted on bearings with the possibility of free rotation, located inside the perforated outer pipe, forming an internal contour and equipped with internal and external impellers; in the upper part of the turbopump there is a mixing chamber for connection fluid flows passing through the internal and external circuits. The cup cuff is designed to allow passage of the power cable without loss of tightness, and the barrel is equipped with a longitudinal guide groove. The mixing chamber is made with a cone-shaped inner surface.

The invention is illustrated by drawings:

Fig.1 – diagram of the device placement in the well;

Figs. 2 and 3 – device for simultaneous oil production from two layers;

Fig.4 – impeller;

Fig.5 – mixing chamber;

Fig.6 – perforated outer pipe of the external circuit.

A device for simultaneous oil production from two layers consists of a barrel 1, made in the form of a cylindrical part, with a cup cuff 2, above which there is a double-circuit turbopump with a perforated outer pipe 9 of the external circuit. The cup cuff 2 is made with the ability to pass the power cable 15 of the electric submersible pump 16 (ESP 16) without loss of tightness in the direction from the terminal box located at the wellhead to the ESP 16, while gas from the lower formation 13, due to its shape, passes upward. The barrel 1 is equipped with a longitudinal guide groove 10 for the power cable 15.

A double-circuit turbopump has an impeller 4 or an assembly of impellers 4, between which bearings 5 are installed, ensuring free rotation of the impellers 4. The cylindrical walls 6 of the impeller 4 or the assembly of impellers 4 form the internal contour of the turbopump. The impeller is equipped with internal and external impellers 7, 8, respectively. The number of blades and their angle of inclination on the internal and external impellers 7, 8 are selected based on the required ratio of the volume of fluid passing along the internal and external contours, otherwise, from the lower and upper layers.

In the upper part of the turbopump there is a mixing chamber 12 (Fig. 5) which can be made as an integral part of it, or as a separate part connected by a threaded connection to the perforated outer pipe 9 of the external circuit. The outer pipe 9 (hollow cylinder) of the outer contour is made perforated, for example, with evenly spaced round holes 3 in its lower part. The mixing chamber ensures the connection of fluid flows passing through the internal and external circuits. To increase efficiency and reduce flow resistance, the mixing chamber is made with a cone-shaped inner surface 11.

The operation of the device for simultaneous oil production from two layers is realized due to the passage of fluid flow from the sub-packer zone created by an electric centrifugal pump along the internal contour of the device, formed by impellers 4 with impellers 7, 8 located along the internal and external contour of the impeller. Due to the transfer of energy by the fluid flow to the internal contour of the impellers, they are untwisted and fluid is taken from the above-packer zone by the impeller of the external contour of the impellers, followed by the connection of flows in the mixing chamber and the further passage of the formation fluid through the tubing lift 17 to the wellhead manifold line.

The device is installed on the tubing 17 with preliminary pulling of the cup cuff 2 through the power cable 15 and lowering the ESP 16 with the cable, depending on the distance between the layers. The equipment is lowered to the calculated depth according to the parameters of the pumping equipment. After piping the wellhead, the ESP 16 is launched, under the influence of the upward flow of liquid and its passage through the internal circuit of the turbopump, the internal impeller 7 unwinds, thereby unwinding the outer impeller 8, which takes liquid through the holes of the outer pipe 9. The liquid passes along the outer contour connects with the internal circuit fluid in the mixing chamber 12 and rises through the cavity of the tubing 17 into the reservoir at the wellhead.

Thus, the energy of the upward flow is used to simultaneously extract fluid from two layers, while operating a single pump. This makes it possible to simplify the device for simultaneous oil production from two layers, while increasing the device's time between failures. The presence of a cup cuff 2 ensures unhindered passage of formation gas from the sub-packer zone to prevent the dynamic level from being squeezed out by gas pressure in the sub-packer zone. If the level decreases below the receiving holes, 3 can be used to extract the gas pack in the production string.

Claims (3)

1. A device for simultaneous oil production from two formations, characterized in that it consists of a barrel with a cup cuff connected to an electric centrifugal pump (ESP) with a power cable, above which there is a double-circuit turbo pump connected to a tubing pipe (Tubing), while a double-circuit pump contains a perforated outer pipe of the outer contour and an impeller or assembly of impellers mounted on bearings with the possibility of free rotation, located inside the perforated outer pipe, forming an internal contour and equipped with internal and external impellers; in the upper part of the turbopump there is a mixing chamber for connecting the flows liquid passing through the internal and external circuits. 2. The device according to claim 1, characterized in that the cup cuff is made with the ability to pass a power cable without loss of tightness, and the barrel is equipped with a longitudinal guide groove. 3. The device according to claim 1, characterized in that the mixing chamber is made with a cone-shaped inner surface.