Pressure releasing device used for double-tube well and capable of sweeping line and tracing heat

Abstract

The invention relates to the technical field of oil and gas development, in particular to a pressure relief device for double-tube well line-sweeping heat tracing, which comprises a double-tube well, an oil well pump, a valve type control valve and a steam boiler, the double-tube well comprises a main tube and a sleeve, an oil pumping pipeline is communicated between the main tube and the oil well pump, a first oil conveying pipeline is communicated between the oil well pump and the valve type control valve, and a second oil conveying pipeline is communicated between the oil well pump and the valve type control valve. The valve type control valve is communicated with a second oil conveying pipeline, a pressure reduction pipeline is communicated between the sleeve and the valve type control valve, and a steam output pipeline is communicated between the steam boiler and the second oil conveying pipeline. The device is reasonable and compact in structure and convenient to use, can effectively reduce the casing pressure of the double-tube well, can perform line sweeping and heat tracing on the main tube of the double-tube well, improves the crude oil recovery rate, and has the characteristics of safety, labor saving, simplicity, convenience and high efficiency.

Description

Technical Field

[0001] This invention relates to the field of oil and gas development technology, and is a pressure relief device for dual-tube wells with sweepable line heating. Background Technology

[0002] In heavy oilfield production using dual-well systems, the pumping unit drives the pump to lift crude oil from the bottom of the well to the surface. Natural gas and high-temperature steam in the crude oil are released into the casing. As the casing pressure increases, it affects the pump's filling coefficient, which is detrimental to crude oil production. To improve oilfield production efficiency and ensure normal well production, periodic or irregular casing gas venting is implemented to reduce casing pressure and increase the submersion of the annulus pump.

[0003] Currently, in a certain oil and gas field's gas storage facility, casing pressure reduction is achieved by manually observing the casing pressure and manually opening valves to reduce pressure. This method has low pressure reduction efficiency and inaccurate control, which can seriously affect the oil well's crude oil recovery rate. On the other hand, as the production cycle of dual-pipe wells extends, the viscosity of crude oil in the main pipe of the dual-pipe well increases, causing slow oil flow in the main pipe, which also affects the oil well's crude oil recovery rate. Summary of the Invention

[0004] This invention provides a pressure relief device for a dual-tube well with sweepable heat tracing, which overcomes the shortcomings of the prior art and can effectively solve the problem of low crude oil recovery rate caused by high casing gas pressure and high crude oil viscosity in the main pipe of existing dual-tube wells.

[0005] The technical solution of the present invention is achieved through the following measures: a pressure relief device for a dual-tube well with sweepable heat tracing, comprising a dual-tube well, an oil pump, a valve-type control valve, and a steam boiler. The dual-tube well includes a main pipe and a casing. An oil pumping pipeline is fixedly connected between the upper oil outlet of the main pipe and the oil inlet of the oil pump. A first oil delivery pipeline is fixedly connected between the oil outlet of the oil pump and the left oil inlet of the valve-type control valve. A second oil delivery pipeline is fixedly connected between the right oil outlet of the valve-type control valve. A pressure reducing pipeline is fixedly connected between the upper air outlet of the casing and the bottom air inlet of the valve-type control valve. A steam production pipeline is fixedly connected between the top steam outlet of the steam boiler and the second oil delivery pipeline.

[0006] The following are further optimizations and / or improvements to the above-mentioned technical solution: The lower fuel inlet of the aforementioned steam boiler is fixedly connected to a natural gas pipeline, and the upper liquid inlet of the steam boiler is fixedly connected to a water inlet pipeline. A first control valve is fixedly installed on the natural gas pipeline, and a second control valve is fixedly installed on the water inlet pipeline.

[0007] The upper second outlet of the aforementioned casing is fixedly connected to a pressure relief pipeline, and a first pressure gauge and a pressure relief valve are fixedly installed on the pressure relief pipeline in sequence along the direction of medium flow.

[0008] The top of the aforementioned main pipe is fixedly connected to a wax removal pipeline, and a third control valve and a vacuum pump are sequentially fixedly installed on the wax removal pipeline along the direction of medium flow.

[0009] A fourth control valve is fixedly installed on the aforementioned oil extraction pipeline.

[0010] A second pressure gauge and a fifth control valve are fixedly installed sequentially along the medium flow direction on the aforementioned pressure reducing pipeline.

[0011] A third pressure gauge is fixedly installed on the aforementioned first oil pipeline.

[0012] A circulating pump, a fourth pressure gauge, and a sixth control valve are fixedly installed sequentially along the direction of medium flow on the aforementioned steam production pipeline.

[0013] A seventh control valve is fixedly installed on the second oil pipeline between the steam production pipeline and the outlet of the second oil pipeline.

[0014] The above also includes a controller, an oil pump, a valve-type control valve, a first control valve, a second control valve, a first pressure gauge, a pressure relief valve, a third control valve, a fourth control valve, a fifth control valve, a second pressure gauge, a third pressure gauge, a circulation pump, a fourth pressure gauge, a sixth control valve, and a seventh control valve, all of which are electrically connected to the controller.

[0015] This invention has a reasonable and compact structure and is easy to use. It meets the requirements of automatic casing pressure release at the wellhead of dual-tube oil wells, providing technical support for oil well casing pressure release production management; it also meets the requirements of heat tracing and wax removal measures for dual-tube oil wells, improving crude oil production efficiency. It is safe, labor-saving, simple and efficient. Attached Figure Description

[0016] Appendix Figure 1 This is a schematic diagram of the process flow of the present invention.

[0017] Appendix Figure 2 For the appendix Figure 1 Schematic diagram of a valve-type control valve.

[0018] The codes in the attached diagram are as follows: 1 for a dual-tube well, 2 for a pumping pump, 3 for a valve control valve, 4 for a steam boiler, 5 for the main pipe, 6 for the casing, 7 for the pumping pipeline, 8 for the first oil delivery pipeline, 9 for the second oil delivery pipeline, 10 for a pressure reducing pipeline, 11 for a steam production pipeline, 12 for a natural gas pipeline, 13 for a water inlet pipeline, 14 for the first control valve, 15 for the second control valve, 16 for a pressure relief pipeline, 17 for the first pressure gauge, 18 for a pressure relief valve, 19 for a paraffin removal pipeline, 20 for the third control valve, 21 for a vacuum pump, 22 for the fourth control valve, 23 for the fifth control valve, 24 for the second pressure gauge, 25 for the third pressure gauge, 26 for a circulation pump, 27 for the fourth pressure gauge, 28 for the sixth control valve, 29 for the seventh control valve, 30 for the outer casing, 31 for a ball valve, 32 for a linkage rod, 33 for a ball valve seat, and 34 for an airflow channel. Detailed Implementation

[0019] The present invention is not limited to the following embodiments, and the specific implementation can be determined according to the technical solution of the present invention and the actual situation.

[0020] Unless otherwise specified, all equipment and devices used in this invention are existing and commonly known in the art.

[0021] In this invention, for ease of description, the description of the relative positions of the components is based on the appendix to the specification. Figure 1 The layout is described using a diagrammatic method, such as the positional relationships of front, back, top, bottom, left, and right, which are based on the instructions attached. Figure 1 The orientation of the layout is determined by the direction of the map.

[0022] The present invention will be further described below with reference to embodiments and accompanying drawings: Example 1: As shown in the attached document Figure 1 As shown, the pressure relief device for a dual-tube well with sweepable heat tracing includes a dual-tube well 1, an oil pump 2, a valve-type control valve 3, and a steam boiler 4. The dual-tube well 1 includes a main pipe 5 and a casing 6. An oil pumping pipeline 7 is fixedly connected between the upper oil outlet of the main pipe 5 and the oil inlet of the oil pump 2. A first oil delivery pipeline 8 is fixedly connected between the oil outlet of the oil pump 2 and the left oil inlet of the valve-type control valve 3. A second oil delivery pipeline 9 is fixedly connected between the right oil outlet of the valve-type control valve 3. A pressure reducing pipeline 10 is fixedly connected between the upper air outlet of the casing 6 and the bottom air inlet of the valve-type control valve 3. A steam production pipeline 11 is fixedly connected between the top steam outlet of the steam boiler 4 and the second oil delivery pipeline 9.

[0023] As required, valve control valve 3, model CF415 DN65-Sch40 TS, is an equal-diameter three-way valve control valve with confluence and reverse flow control functions, as shown in the attached document. Figure 1 , 2As shown, the valve control valve 3 consists of a housing 30, a valve ball 31, a linkage rod 32, and a valve ball seat 33. The pressure relief process of this device is as follows: the linkage rod 32 controls the valve ball 31 to sit on the valve ball seat 33. The crude oil extracted from the main pipe 5 by the oil pump 2 enters through the left inlet of the valve control valve 3 and flows out through the right outlet of the valve control valve 3. When the gas pressure in the casing 6 is too high, it enters the bottom valve ball seat 33 of the valve control valve 3 through the pressure reducing pipeline 10 (the valve ball seat has an airflow channel 34). After the valve ball 31 is lifted off the valve ball seat 33 by the impact force of the airflow, the airflow immediately enters the cavity of the valve control valve 3 and is discharged from the right outlet of the valve control valve 3 along with the crude oil. The line sweeping and heat tracing process of this device is as follows: the linkage rod 32 controls the valve ball 34 to be fixed away from the valve ball seat 33. The steam in the steam boiler 4 can enter from the right port of the valve control valve 3 through the second oil pipeline 9 and then flow out through the airflow channel 34 of the valve ball seat 33. It enters the casing 6 through the pressure reducing pipeline 10 for line sweeping and heat tracing.

[0024] The pressure relief device for dual-tube wells with sweepable heat tracing can be further optimized and / or improved according to actual needs: Example 2: Its difference from Example 1 is as follows: (See attached) Figure 1 As shown, the lower fuel inlet of the steam boiler 4 is fixedly connected to a natural gas pipeline 12, and the upper liquid inlet of the steam boiler 4 is fixedly connected to a water inlet pipeline 13. A first control valve 14 is fixedly installed on the natural gas pipeline 12, and a second control valve 15 is fixedly installed on the water inlet pipeline 13.

[0025] Example 3: Its difference from Examples 1 to 2 is as follows: (See attached) Figure 1 As shown, the second outlet at the upper part of the sleeve 6 is fixedly connected to a pressure relief pipeline 16, and a first pressure gauge 17 and a pressure relief valve 18 are fixedly installed on the pressure relief pipeline 16 along the medium flow direction.

[0026] If the steam pressure inside the sleeve 6 is too high when the device is performing wire sweeping and heat tracing, the steam inside the sleeve 6 can be released through the pressure relief pipeline 16.

[0027] Example 4: Its difference from Examples 1 to 3 is as follows: (See attached) Figure 1 As shown, a wax removal pipeline 19 is fixedly connected to the top of the main pipe 5, and a third control valve 20 and a vacuum pump 21 are fixedly installed on the wax removal pipeline 19 along the direction of medium flow.

[0028] Example 5: It differs from Examples 1 to 4 in that, as shown in the appendix... Figure 1 As shown, a fourth control valve 22 is fixedly installed on the oil extraction pipeline 7.

[0029] Example 6: Its difference from Examples 1 to 5 is as follows: (See attached) Figure 1As shown, a second pressure gauge 24 and a fifth control valve 23 are fixedly installed sequentially along the medium flow direction on the pressure reducing pipeline 10.

[0030] Example 7: Its difference from Examples 1 to 6 is as follows: (See attached) Figure 1 As shown, a third pressure gauge 25 is fixedly installed on the first oil pipeline 8.

[0031] Example 8: It differs from Examples 1 to 7 in that: as shown in the appendix Figure 1 As shown, a circulating pump 26, a fourth pressure gauge 27, and a sixth control valve 28 are fixedly installed along the medium flow direction on the steam production pipeline 11.

[0032] Example 9: It differs from Examples 1 to 8 in that: as shown in the appendix Figure 1 As shown, a seventh control valve 29 is fixedly installed on the second oil pipeline 9 between the steam production pipeline 11 and the outlet of the second oil pipeline 9.

[0033] Example 10: It differs from Examples 1 to 9 in that, as shown in the appendix... Figure 1 As shown, the device also includes a controller, an oil pump 2, a valve-type control valve 3, a first control valve 14, a second control valve 15, a first pressure gauge 17, a pressure relief valve 18, a third control valve 20, a fourth control valve 22, a fifth control valve 23, a second pressure gauge 24, a third pressure gauge 25, a circulation pump 26, a fourth pressure gauge 27, a sixth control valve 28, and a seventh control valve 29, all of which are electrically connected to the controller.

[0034] Depending on the requirements, the pipelines and equipment of this pressure relief device for dual-well swept-line heat tracing can also be equipped with conventional valves, thermometers, and pressure gauges known in the art, according to production needs. The controller is a DCS controller, and the model of the DCS controller can be 6ES7288-1SR40-0AA0.

[0035] The above technical features constitute various embodiments of the present invention, which have strong adaptability and implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the needs of different situations.

[0036] The usage process of this invention embodiment is as follows: First, after the oil pump 2 draws crude oil from the main pipe 5, it enters the valve control valve 3 through the first oil delivery pipeline 8; then, when the gas pressure in the casing 6 is too high (when the second pressure gauge 24 shows that the pressure in the casing 6 is over-pressured, the fifth control valve 23 automatically interlocks and opens), the gas enters from the bottom air inlet of the valve control valve 3 through the pressure reducing pipeline 10 (the valve control valve 3 automatically interlocks and opens to achieve positive merging), maintaining the gas pressure in the casing 6 stable; finally, the crude oil and gas in the valve control valve 3 flow out from the right port of the valve control valve 3 and are transported to the downstream process system through the second oil delivery pipeline 9.

[0037] The above embodiment also includes the following steps: First, the fourth control valve 22 and the seventh control valve 29 are closed respectively, and steam is produced by using the natural gas produced by the oil and gas field as fuel for the steam boiler 4. Then, the steam enters the valve control valve 3 in reverse through the steam production pipeline 11 and the second oil pipeline 9, and is discharged from the bottom of the valve control valve 3 (the valve control valve 3 automatically interlocks to open to achieve reverse flow). Next, the steam flows back into the casing 6 through the pressure reducing pipeline 10, and the steam in the casing 6 heats the medium in the main pipe 5 (the heat from the steam in the casing 6 is transferred into the main pipe 5), reducing the viscosity of the crude oil in the main pipe 5 (heating melts the wax precipitates in the crude oil). Finally, the oil in the main pipe 5 is discharged into the downstream process system for recycling through the dewaxing pipeline 19.

Claims

1. A pressure relief device for dual tubing well sweep line heat tracing, characterized by The system includes a dual-tube well, an oil pump, a valve control valve, and a steam boiler. The dual-tube well consists of a main pipe and a casing. An oil pumping pipeline is fixedly connected between the upper oil outlet of the main pipe and the oil inlet of the oil pump. A first oil delivery pipeline is fixedly connected between the oil outlet of the oil pump and the left oil inlet of the valve control valve. A second oil delivery pipeline is fixedly connected between the right oil outlet of the valve control valve. A pressure reducing pipeline is fixedly connected between the upper air outlet of the casing and the bottom air inlet of the valve control valve. A steam production pipeline is fixedly connected between the top steam outlet of the steam boiler and the second oil delivery pipeline.

2. The pressure relief device for dual tubing well sweep line heat tracing of claim 1, wherein The lower fuel inlet of the steam boiler is fixedly connected to a natural gas pipeline, and the upper liquid inlet of the steam boiler is fixedly connected to a water inlet pipeline. A first control valve is fixedly installed on the natural gas pipeline, and a second control valve is fixedly installed on the water inlet pipeline.

3. The pressure relief device for dual tubing well sweep line heat tracing according to claim 1 or 2, characterized in that The second outlet at the upper part of the casing is fixedly connected to a pressure relief pipeline, and a first pressure gauge and a pressure relief valve are fixedly installed on the pressure relief pipeline in sequence along the direction of medium flow.

4. The pressure relief device for dual tubing well sweep line heat tracing of claim 3, wherein The top of the main pipe is fixedly connected to a wax removal pipeline, and a third control valve and a vacuum pump are fixedly installed on the wax removal pipeline in sequence along the direction of medium flow.

5. The pressure relief device for dual string well sweep line heat tracing of claim 1 or 2 or 4, wherein A fourth control valve is fixedly installed on the oil extraction pipeline.

6. The pressure relief device for a dual-tube well with sweepable heat tracing as described in claim 5, characterized in that... A second pressure gauge and a fifth control valve are fixedly installed sequentially along the medium flow direction on the pressure reducing pipeline.

7. The pressure relief device for a dual-tube well with sweepable heat tracing according to claim 1, 2, 4, or 6, characterized in that... A third pressure gauge is fixedly installed on the first oil pipeline.

8. The pressure relief device for a dual-tube well with sweepable heat tracing according to claim 7, characterized in that... A circulating pump, a fourth pressure gauge, and a sixth control valve are fixedly installed sequentially along the direction of medium flow on the steam production pipeline.

9. The pressure relief device for a dual-tube well with sweepable heat tracing according to claim 8, characterized in that... A seventh control valve is fixedly installed on the second oil pipeline between the steam production pipeline and the outlet of the second oil pipeline.

10. The pressure relief device for a dual-tube well with sweepable heat tracing according to claim 9, characterized in that... It also includes a controller, an oil pump, a valve-type control valve, a first control valve, a second control valve, a first pressure gauge, a pressure relief valve, a third control valve, a fourth control valve, a fifth control valve, a second pressure gauge, a third pressure gauge, a circulation pump, a fourth pressure gauge, a sixth control valve, and a seventh control valve, all of which are electrically connected to the controller.

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