RU115001U1 - REAGENT SUBMERSIBLE CONTAINER - Google Patents

Abstract

Submersible container for reagent, located under the base of the submersible electric motor ESP, containing a body in the form of a pipe, a separating piston, a base with a membrane, an end cap with a breathing hole, characterized in that the piston is made with radial recesses filled with a synthetic fluid that does not mix with media , in this case, the reagent is enclosed in a volume between the membrane or a reusable check valve and the piston, which, under the action of negative pressure, has the ability to move along the axis of the body, enters the controlled dosing unit through a puncture in the membrane, and the pressure difference is compensated through a hole in the end cap.

Description

The utility model relates to the field of oil and gas and is intended to protect submersible downhole equipment, for example, pumping units from complications.

Known container dispenser, consisting of a pipe-body, covered with a grid, plates and core pipes, and the chemical is placed in the space between the pipe-core and the walls of the housing. The dispensing container is attached to the bottom of the submersible equipment (pump) and lowered into the well together with the specified pump (Prevention of salt formation during oil production. M; Nedra, 1985, p.192).

The disadvantage of this device is the inability to create a shock dose of a chemical at the stage of putting the well into operation. As the chemical reagent dissolves, the flushing area of this reagent with the well fluid decreases and, accordingly, the reagent decreases in the fluid. Another disadvantage is the rigid attachment of the metering container to the submersible pump, which increases the overall length of the installation and increases the bending loads on the submersible equipment during its operation in deviated wells.

A device is known, which is a container of uniformly perforated pipes filled with a mixture of inhibitor and bitumen, cast in the form of pieces or cylinders (RU No. 2132451 U1, database of abstracts of Russian patent documents FIPS). Through perforation in the pipe walls, the produced fluid interacts with the specified bitumen-inhibitor mixture.

The disadvantage of this device is that it does not provide a sufficient supply of reagent to the wellbore fluid at the stage of putting the well into operation. When the device is operating for a long time, the flow of the chemical is reduced. This reduces the reliability of downhole equipment protection.

A device for supplying a solid reagent to a well (RU No. 2227206 U1, database of abstracts of Russian patent documents FIPS) is made in the form of two or more perforated sections for placement of a solid reagent in them, while the sections are interconnected sequentially at the ends by means of a connecting unit and communicated with each other through holes in the perforated base, and the perforated channels in the body of each section are made evenly and depending on the type of solid reagent, well flow rate and water cut in the layers oh water have a certain size.

The disadvantage of this device is the inability to create with it an initial increase in the concentration of a chemical agent when a well is brought into operation, as well as an uncontrolled decrease in concentration during prolonged operation. Another disadvantage of the device is that the rigid mount increases the total length of the installation and increases the bending loads on the submersible pump in deviated wells. This causes deformation of the submersible pump installation, wear of the working parts of the pump, its vibration and reduces the service life.

The device cannot be used for storage and transportation of the reagent. The disadvantage of this device is the use of perforated pipes with increased wall thickness to place threads on the metal of these pipes. This increases the weight of the device and reduces the share of payload.

It is also known a device (RU No. 47944 U1, database of abstracts of Russian patent documents FIPS), made in the form of two perforated hollow sections for placement of reagent, while the sections are connected to each other in series with the ends of the connecting node and communicated with each other through holes in the perforated bottom . The above device can be taken as a prototype.

The main disadvantage of all the above devices is the large linear dimensions, as well as uncontrolled input and diffusion of the reagent when changing the percentage of oil and its derivatives in the reservoir fluid.

The problem is solved in that the output of the reagent is carried out into the annulus through the hollow breakdown element and a puncture in the membrane, as well as a controlled dosing unit, for example an electromagnetic valve.

The technical result is achieved in that the device comprises a housing in the form of a pipe, a hollow breakdown element, a piston separating the base with the membrane, an end cap with a breathing hole. The piston is made with radial recesses, which are filled with a synthetic fluid that is not miscible with the media, which is a reagent that prevents the formation of salts on the working bodies of the ESP. In this case, the reagent is enclosed in a volume between the membrane and the piston, which under the influence of negative pressure has the ability to mix along the axis of the housing, enters the receiving channel of a known controlled distribution or dosing unit through a hollow breakdown element and a puncture in the membrane, and the pressure difference is compensated through the hole in the end the lid.

As a membrane, a multiple-acting check valve can be used.

The design of the submersible container for the reagent is illustrated in the drawing. The figure shows a General view of a utility model containing a housing 1, inside of which is coaxially mounted a piston 4 with radial recesses connected to each other by channels filled with synthetic fluid 3, consisting of a mixture of known synthetic oil with 2% xanthan gum. The density and viscosity of the synthetic fluid is selected depending on the type of reagent used and the operating conditions of the equipment in the well (temperature, pressure). On the one hand, the housing 1 is hermetically closed by a base with a membrane 5, which is fixed by a support ring 6, on the other hand, by an end cap 2 with a breathing hole. The piston 4 divides the housing 1 into two mutually sealed volumes A and B. Volume A is filled with reagent, volume B is filled with formation fluid after being lowered into the well.

The reagent immersion container works this way. When assembling, the proposed model is placed vertically, under the base of the submersible motor, so that the membrane 5 is facing in the opposite direction. Through a puncture in the membrane 5, the reagent through a hollow breakdown element and a puncture in the membrane enters a controlled dosing unit, for example, an electromagnetic valve. Under the action of gravity and negative pressure, the piston 4 moves downward, remaining at the upper boundary of the reagent mirror. As the piston 4 moves, volume B is filled with reservoir fluid through the breathing hole in the end cap 2. The mixing of volumes A and B is limited by the surface tension forces of the synthetic fluid 3. The reagent submersible container has an optimal design and increased reliability compared to prototypes.

Claims (1)

Immersion container for reagent, located under the base of the ESP submersible motor, comprising a tube-shaped housing, a separating piston, a base with a membrane, an end cap with a breathing hole, characterized in that the piston is made with radial recesses that are filled with a synthetic fluid that is not miscible with media while the reagent is enclosed in a volume between the membrane or a multiple-acting check valve and a piston, which under the influence of negative pressure has the ability to move along the axis of the housing, it enters the controlled dosing unit through a puncture in the membrane, and the pressure difference is compensated through the hole in the end cap.