RU2100579C1 - Sucker-rod pumping unit for operation of marginal wells - Google Patents

Abstract

FIELD: oil-and-gas producing industry. SUBSTANCE: tubing string is separated by two pumping devices into two stages of lifting. It is separated at the preset depth by separating pumping-over device. It is installed at the preset height from lower pumping device. This height is determined by the value of accumulating chamber and depth of lowering of downhole pumping unit. It consists of two concentric strings: hollow sucker rods and tubings. Tubings above separating pumping-over device form two channels. Tubings form channel for lifting well production through annular space. Hollow rods form channel for supply of chemical reagents. Below the separating pumping-over device, the intertubing annular space is communicated from upper side with wellbore annular space, and from the other side, through guide and intake chambers is communicated with pump and lower part of hollow rod to tubing string. Separating pumping-over device consists of body with radial channels, sleeve and separating piston. The latter is fitted on hollow rod. Rod is rigidly connected with hollow rods. Located on rod are check, intake and pressure valves. Lower and upper partitions on rod form, correspondingly, upper and lower chambers. Lower chamber communicated through intake gas valve is communicated with hollow of lower part of hollow rods and, through pressure valve, with hollow rod. Upper chamber, through intake gas valve is communicated with wellbore annular space. Installed on upper partition is pressure valve for gas. Device for supply of chemical reagents includes vessel for chemical reagents. The vessel is connected, from one side, with gas pipeline, and from the other side, with pipeline. The latter is communicated with additional sleeve and upper part of string of hollow rods. They pass above separating pumping-over device through sleeve and further on, through radial annular channels are connected with accumulation chamber. EFFECT: higher efficiency. 1 dwg

Description

 The invention relates to the oil industry and is intended for oil production from low and medium production wells.

Known sucker-rod pumping unit for pumping fluid from wells, consisting of wellhead fittings, columns of lifting pipes, rods, a downhole pump, including a housing, cylinder, plunger, discharge and suction valves [1]
The disadvantages of the known pump are:
lack of efficiency, the submersible pump operates with a low feed rate during continuous pumping and with oil shortages during periodic pumping of well fluid from wells;
high energy consumption;
the impossibility of operational regulation of the supply of chemical reagents to the fluid entering the deep pump. Closest to the technical nature of the claimed invention is a downhole pumping unit for operating low-production wells in a periodic pumping mode, which consists in a continuous flow of fluid from the alloy into the well and accumulation in a continuous flow of fluid from the formation into the well and its accumulation in the annulus and in its periodic pumping out [2]
The disadvantages of the known installation are:
the presence of a packer in the annulus, accompanied by the accumulation of free gas in the under-packer space, displacing the fluid to the shank shoe;
the impossibility of prompt supply and regulation of the amount of supplied chemical reagents in the pumped liquid;
limited volume of well fluid accumulated in the annulus due to the descent into the well of two columns of lifting pipes and a column of hollow rods concentrically located relative to each other.

 The objective of the invention is to increase the efficiency of the well and the rod deep well pumping unit.

 The problem is solved in that the sucker rod pumping unit for operating low-production wells, comprising wellhead equipment with a flow line, a pump pipe string, a hollow rod string placed in a pump pipe string, and a deep pump placed on a hollow rod string are provided with a gas pipeline, a piping for supplying chemical reagents in communication with a gas pipeline and a separation-transfer device rigidly connected to a column of pump pipes made of a housing with radial and the main channels, the cup, the hollow rod, rigidly connected with the hollow rods, and having a check, receiving and discharge valves, a lower baffle with a discharge gas valve and a separation piston, mounted on the hollow rod, and tubing and hollow rods form under the separation the transferring chamber with a length specifying the installation depth of the separation and transfer device and communicated in the upper part with the annular space, the guide and receiving chambers reporting a feeding chamber with a pump and the lower part of the hollow rods, and a lifting column connected to the discharge pipe above the separation-pumping device, while the lower and upper partitions form the lower and upper chambers, the last of which communicates with the annulus through the gas intake valve, and the first communicates with the cavity of the rods in their lower part through the inlet valve and, through the discharge valve with a hollow rod connected through a blind sub to the upper part of the hollow rods, which are nalom for feeding chemical reagents and reported, on the one hand, through the glass, radial and annular channels with storage chamber and on the other hand through an additional cup is rigidly fixed to the mouth, and communicated with a container for chemicals.

 A comparative analysis of the proposed solution with the prototype shows that the claimed installation differs from the existing one by the presence of an upper separation-pumping device, which allows to redistribute the load both from the weight of the liquid and the rod string, removing part of the load from the weight of the liquid from the lower pump by the upper and the liquid support supplied by the lower pump to the upper plunger, and compensate for part of the load from the weight of the liquid and the rod string located above the separation-pumping device, and thereby increase l the length of the storage chamber, and the use of hollow rods in the area of the storage chamber and the tubing string as its body allows increasing their diameter to a rationally larger value, which also increases the scope of periodic pumping of fluid from wells . It is also distinguished by the presence of devices for supplying chemical reagents to the well, consisting of pipelines for supplying the chemical reagent with gas from the chemical reagent tank, which is communicated through pipelines with an additional glass fixed in the wellhead equipment and a column of hollow rods passing through it, the lower part of which is connected to the glass located in the upper part of the separation-pumping device, which through radial and annular channels communicates with the storage chamber, into which continuously blunt chemical reagent and mixing with fluid entering the well, while its subsequent accumulation in the chamber provides its demulsification and degassing.

 It is also distinguished by the fact that the presence of a separation and pumping device allows you to redistribute the load on the downhole pumping devices and rods located in the lower and upper parts of the lifting column, as well as the leakage of the liquid as a whole through the downhole pumping unit.

 The installation, the scheme of which is shown in the drawing, includes wellhead equipment 1 with gas 2, flow 3 and feed reagents 4 pipelines, a container for chemical reagents 5, a pump 6, lowered on a column of pump pipes 7, a column of hollow rods 8 and separation and transfer device 9 rigidly connected to the column of pump pipes 7 and located at a calculated distance from the deep pump 6, based on the optimal operating mode of the reservoir-well-equipment system, and form with the bottom of the pump pipes 7 and hollow rods 8 nuyu chamber 10 provided by the top channel 11 with the annular space, the bottom channel 12 through the guide 13 and the receiving chamber 14 with the pump 6 and the bottom 8 of the hollow rods.

 The upper part of the pump pipes 7 and the hollow rods 8, which is located above the separation and pumping device 9, forms a lifting column for the well fluid connected to the flow line 3. The separation and pumping device 9 consists of a housing with radial 15 and ring 16 channels, a cup 17, a separation piston 18, mounted on a hollow rod 19, which is higher and lower than the separation and pumping device 9 is rigidly connected to the lower and upper parts of the column of hollow rods 8, and with the upper part of the column of hollow pants d 8, the hollow stem 19 is connected through a blind sub 20. On the hollow stem 19 there are return 21, inlet 22 and pressure valves 23 and 24. The separation-pumping device 9 also includes the lower 25 and upper 26 partitions, which form the lower 27 and upper 28, respectively chambers, the lower 27 of which through the inlet valve 22 communicates with the cavity of the lower part of the hollow rods 8, through the discharge 23 with the hollow rod 19, the upper chamber through the inlet gas valve 29 with the annulus, and the discharge is installed on the upper partition 26 th valve for gas 30. The upper part of the hollow rods 8 is connected to a solid rod 31, and their cavity 32 is a channel for supplying reagent, bottom communicated through a glass 17 and radial-ring 15, 16 channels of the separation-pumping device 9 with a storage chamber 10, from above through a glass 33, rigidly fixed to the wellhead equipment 1, is in communication with a tank 5 for a chemical reagent, which in turn is in communication with a gas pipeline 2. Gas pipeline 2 is equipped with a pipe 34 for connecting various units for supplying steam, hot oil, water and gas to the well. The rod deep pump installation is assembled, lowered into the well and operates as follows.

 The deep pump 6 starts up and the liquid located in the storage chamber 10 and again entering the chamber during the cleaning period through the openings 11 is pumped out before the pump is received or to a predetermined level in the storage chamber 10. The liquid pumped out by the deep pump 6 rises along the hollow rods 8 and when they move upward at a predetermined depth, it enters the lower 27 chamber of the separation-pumping device 9, from where it is wrung out during the separation piston 18 downward through the discharge valve 23 into the hollow rod 19 and then through the discharge The valve 24 is squeezed into the upper part of the lifting column of the pump pipes 7. At the same time, when the separation piston 18 is reciprocating (when it moves downward), gas is sucked in from the annulus through the intake valve 29 into the upper chamber 28, which is squeezed out of it during the separation piston 18 upwards, through the discharge gas valve 30 into the lifting column, diluting the liquid rising along it, which enters the discharge line.

 In the process of operation of the proposed installation, a continuous supply of a chemical reagent is provided from a tank 5 located at the wellhead and connected on the one hand to the gas pipeline 2 and, on the other, through the pipe 4, a glass 33 rigidly fixed to the wellhead 1, with a cavity 32 of upper rods 8, which is connected through the cup 17, radial 15 and annular 16 from the bottom to the storage chamber 10. The chemical reagent is fed into the well under gas pressure, as can be seen in the drawing, coming through pipeline 2 from the annulus wells.

 In cases where paraffin is deposited in the production string or highly viscous fluids are extracted from the well, saturated or superheated steam, hot oil, water or gas from special units can be supplied through hollow rods, for which purpose a pipe 34 is provided on the gas pipeline.

 Thus, the use of the proposed rod installation will increase the profitability of the operation of all categories of wells due to the operation of the reservoir and downhole equipment in the optimal mode, and by eliminating the significant impact on the operation of the installations of the composition and structural properties of the produced fluid. This is especially important during the operation of fields at a late stage of development, which, as a rule, are characterized by the presence of an old well stock, high water cut and the formation of highly viscous emulsions, as well as in the development of fields with highly viscous oil.

Claims (1)

 A sucker rod pump installation for operating low-flow wells, comprising wellhead equipment with a flow line pipe, a pump pipe string, a hollow pipe string placed in a pump pipe string, and a downhole pump placed on a hollow rod string, characterized in that it is provided with a gas pipeline, a pipeline for supply of chemical reagents, a container for chemical reagents, in communication with a gas pipeline and separation and pumping device, rigidly connected with a column of pumping pipes made of case with radial and annular channels, a glass, a hollow rod rigidly connected with hollow rods, and having a check, receiving and discharge valves, a lower baffle, an upper baffle with a gas discharge valve, and a dividing piston, mounted on the hollow rod, and pump pipes and the hollow rods form a storage chamber under the separation-transfer device with a length defining the installation depth of the separation-transfer device and communicated in the upper part with the annulus the receiving chamber, communicating the storage chamber with the pump and the lower part of the hollow rods, and above the separation and pumping device, a lifting column connected to the discharge pipe, while the lower and upper partitions form respectively the lower and upper chambers, the last of which communicates with the annulus through the receiving gas valve, and the first is connected with the cavity of the rods in their lower part through the intake valve and through the discharge valve with a hollow rod connected through a blind sub to the upper part hollow rods, which are a channel for supplying chemicals and communicated on one side through the glass, radial and annular channels with storage chamber and on the other hand through an additional cup is rigidly fixed to the mouth, and communicated with a container for chemicals.