Sand jam prevention screw pump for oilfield production well and well jamming release method after well jamming

Abstract

The application discloses a sand jam prevention screw rod pump for an oilfield production well and a well jam releasing method after well jam, and belongs to the oilfield production field. The sand jam prevention screw rod pump is provided with a hollow rod, the top end of the hollow rod is connected with a hollow rod plug through a ground driving device, and the bottom end of the hollow rod is connected with a screw rod pump hollow rotor through a hollow rod inner swivel joint. A tubing is arranged outside the hollow rod, and a sand jam prevention joint is arranged between the tubing and the hollow rod. The outer side of the screw rod pump hollow rotor is provided with a screw rod pump stator, and the lower side of the screw rod pump is provided with a tubing anchor. The application can realize the staged sedimentation of sand carried by liquid in the tubing when the well is stopped, and can avoid the sticking of the pumping rod.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of oil extraction, and particularly relates to a sand jam prevention screw pump for an oil production well and a well jam release method after well jam. BACKGROUND

[0002] Petroleum is a fluid mineral buried deep in the ground. Initially, people called the oil-like liquid mineral produced in nature petroleum, called natural gas for the combustible gas, and called asphalt for the solid combustible oil mineral. With the in-depth study of these minerals, it is realized that they are all hydrocarbon compounds in composition and are related in origin, so they are collectively referred to as petroleum. In September 1983, the 11th World Petroleum Conference proposed that petroleum is a complex mixture composed of gaseous, liquid and solid hydrocarbon compounds and a small amount of impurities existing in nature. Therefore, petroleum exploitation also includes natural gas exploitation.

[0003] The role of petroleum in the national economy Petroleum is an important energy source, compared with coal, it has the advantages of high energy density (the combustion heat of equal weight of petroleum is 50% higher than that of standard coal), convenient transportation and storage, and less air pollution after combustion. Fuel oil refined from petroleum is the main fuel for transportation tools, power station boilers, metallurgical industry and various kilns in the building material industry. Liquefied gas and pipeline gas made of petroleum are high-quality fuels for urban residents. Aircraft, tanks, warships, rockets and other spacecraft also consume a large amount of petroleum fuel. Therefore, many countries have listed petroleum as a strategic material.

[0004] Since the 1970s, in the composition of world energy consumption, petroleum has surpassed coal and ranked first. In 1979, it accounted for 45%, and it is expected that there will be no big change by the beginning of the 21st century. Petroleum products are also widely used as lubricants for various machines. Asphalt is an important material for highways and buildings. Petroleum chemical products are widely used in agriculture, light industry, textile industry and medical and health departments, such as synthetic fibers, plastics and synthetic rubber products, which have become necessities of life for people.

[0005] Petroleum engineering is the process technology of the entire process of lifting oil and gas from the bottom of the well to the wellhead. The upward movement of oil and gas can rely on the energy of the formation to flow naturally, or rely on the artificially supplemented energy of the oil pump, gas lift, etc. Various effective well repair measures can eliminate the frequent faults of oil wells such as wax precipitation, water production and sand production, and ensure normal production of oil wells. Water fracturing or acidizing and other stimulation measures can improve the production capacity reduced due to low oil layer permeability or improper drilling technical measures to pollute and damage the oil and gas layer. For injection wells, it is to improve the injection capacity. The oilfield screw pump is commonly used in production.

[0006] At present, in the production well of oilfield screw pump, because the screw pump has a certain sand carrying capacity, when the production well of screw pump stops due to power failure, ground equipment failure and other conditions, the sand carried by the liquid in the tubing falls back, and the sand buries the screw or the sucker rod, causing the well to be stuck, after the well is stuck, the screw pump generally cannot produce after the well is opened, and needs to be operated to pull out the stuck part, if the operation is successful, the rotor can be circulated to wash the well, and then the well is opened to continue production, if the operation is unsuccessful, the tubing rod in the well needs to be pulled out by force for replacement of the new pump and rod, whether the operation is successful or not, economic waste is caused, and the operation workload is increased.

[0007] Because the rotors of the screw pumps used in the field are solid, the well after the screw pump cannot be washed, and after the flow of crude oil stops, the viscosity increases, the flowability becomes poor, the torque of the sucker rod is large after the well is opened again, the sucker rod is overloaded, and problems such as breakage and thread damage of the sucker rod often occur, and the screw is also twisted off, so that the normal production time of the screw pump oil production well is short, and frequent operation and maintenance are needed, and the efficiency of the oil production well is low.

[0008] It is found through retrieval that the patent 201520096664.2, the sand sticking prevention device for screw pump oil production, can limit sand sinking, but is still easy to be stuck, and cannot circulate to wash the well. The technology in the document of technical analysis of the sand sticking prevention device for screw pump oil production can limit sand sinking, but is still easy to be stuck. The patent CN201520023611.8, a sand sticking prevention device for screw pump, cannot realize well washing without moving the tubing string. The patent CN03216511.0, a sand sticking prevention device for screw pump oil production, cannot realize well washing without moving the tubing string. The patent CN02203594 cannot realize well washing without moving the tubing string. SUMMARY

[0009] In view of the above problems, the present application provides a sand sticking prevention screw pump for oilfield production well and a well sticking release method, the screw pump can realize staged sedimentation of the sand carried by the liquid in the tubing when the well stops, and can avoid the sucker rod from being stuck.

[0010] The sand sticking prevention screw pump of the present application is provided with a hollow rod, the top end of the hollow rod is connected with a hollow rod plug through a ground driving device, and the bottom end of the hollow rod is connected with a screw pump hollow rotor through a hollow rod inner swivel joint. An oil pipe is arranged outside the hollow rod, and a sand sticking prevention joint is arranged between the oil pipe and the hollow rod. A screw pump stator is arranged outside the screw pump hollow rotor, and an oil pipe anchor is arranged below the screw pump.

[0011] The present application also protects a release method, and the steps of the method are as follows:

[0012] (1) An oil pipe is connected with a sand sticking prevention joint at a certain distance;

[0013] (2) During normal production, the liquid in the well is transmitted upwards from each chamber of the screw pump, when the pressure in the oil pipe is too high, the liquid breaks through the sand sticking prevention joint and moves to the wellhead to produce normally.

[0014] (3) According to the screw pump current card situation, if the current abnormally rises, the well can be directly washed, and the abnormal resistance in the well is removed in advance.

[0015] (4) When the screw pump ground fails, the fine sand carried by the liquid in each section of the oil pipe will slowly settle on the sand prevention joint, so that the fine sand carried by the entire wellbore liquid can be graded and settled on each sand prevention joint, preventing the fine sand from being completely settled above the screw pump stator as before, and each joint only bears a small amount of sand settlement, avoiding the large amount of sand settlement from sticking the sucker rod, and greatly increasing the success rate of opening the well.

[0016] (5) After the ground failure is eliminated, the well is directly opened, and the well opening is successful and normal production is directly carried out.

[0017] (6) If it is not successful, a cement truck is connected to carry out bidirectional circulation well washing through the casing and the hollow rod plug, the washing fluid can enter the oil pipe through the hollow rotor, and the washing fluid can also enter the oil pipe through the hollow rod to wash out the sand settled on each sand prevention joint in the oil pipe and remove the sand sticking.

[0018] (7) The well is opened and normal production is carried out.

[0019] Beneficial effects:

[0020] (1) The present application can realize the graded settlement of the sand carried by the liquid in the oil pipe when the well is stopped, and avoid the sticking of the sucker rod.

[0021] (2) The present application can realize the circulation well washing without moving the pipe column when the screw pump sand sticking sucker rod occurs.

[0022] (3) The present application has simple design and strong practicability. DETAILED DESCRIPTION

[0023] Figure 1 It is a schematic diagram of the overall structure of the present application.

[0024] As shown in the figure, 1. Hollow rod plug, 2. Ground driving device, 3. Hollow rod, 4. Oil pipe, 5. Sand prevention joint, 6. Hollow rod inner reversing joint, 7. Screw pump stator, 8. Hollow rotor of screw pump, 9. Oil pipe anchor. DETAILED DESCRIPTION

[0025] The present application will be further described below in combination with examples.

[0026] Example 1

[0027] When the pump is down, a sand prevention joint 5 is connected to the oil pipe every 100 meters. During normal production, the liquid in the well is transmitted upward from each chamber of the screw pump, and when the pressure in the oil pipe is too high, the liquid breaks through the sand prevention joint 5 and moves to the wellhead for normal production. According to the current card of the screw pump, if the current abnormally rises, the well can be directly washed, and the abnormal resistance in the well is removed in advance. When the screw pump on the ground fails, the fine sand carried by the liquid in the oil pipe every 100 meters will slowly settle on the sand prevention joint 5, so that the fine sand carried by the entire wellbore liquid can be graded and settled on each sand prevention joint 5, preventing the entire sand from settling above the screw pump stator 7, and each sand prevention joint 5 only bears a small amount of sand, avoiding the large amount of sand from being stuck in the sucker rod, greatly increasing the success rate of opening the well. After the ground fault is removed, the well is directly opened, and the well is directly produced normally. If it is not successful, a cement truck is connected through the casing and hollow rod plug for bidirectional circulation washing, and the washing fluid can enter the oil pipe through the hollow rotor or the hollow rod to wash out the sand on each sand prevention joint 5 in the oil pipe and remove the sand sticking. The well is opened and normal production is restored.

[0028] Example 2

[0029] For a well with severe sand production, a sand prevention joint 5 is connected to the pump every 50 meters. During normal production, the liquid in the well is transmitted upward from each chamber of the screw pump, and when the pressure in the oil pipe is too high, the liquid breaks through the sand prevention joint 5 and moves to the wellhead for normal production. According to the current card of the screw pump, if the current abnormally rises, the well can be directly washed, and the abnormal resistance in the well is removed in advance. When the screw pump on the ground fails, the fine sand carried by the liquid in the oil pipe every 50 meters will slowly settle on the sand prevention joint 5, and below the pump depth of 1000 meters, the entire oil pipe has a sand column of 10m for example. In this way, each sand prevention joint 5 bears an average of 0.5 meters of sand column, and these sands will not compact the sucker rod, and as long as a certain torque is applied, the well can be normally operated. If the sand prevention joint 5 is not installed every 100 meters or 200 meters, the 1 meter or 2 meters or even 10 meters of sand column falling on the sand prevention joint 5 will completely compact the sucker rod, and the ground cannot normally open the well, and the well cannot be washed.

[0030] Example 3

[0031] When the pump is down, a sand prevention joint 5 is connected every 200 meters of the oil pipe. During normal production, the liquid in the well is transmitted upwards from each chamber of the screw pump, and when the pressure in the oil pipe is too high, the liquid breaks through the sand prevention joint 5 to move to the wellhead for normal production. According to the current card of the screw pump, if the current abnormally rises, the well can be directly washed, and the abnormal resistance in the well is removed in advance. When the screw pump on the ground fails, the fine sand carried by the liquid in the oil pipe every 200 meters will slowly settle on the sand prevention joint 5, so that the fine sand carried by the liquid in the entire wellbore can be settled on each sand prevention joint 5 in stages, preventing the fine sand from being completely settled above the screw pump stator 7, and each sand prevention joint 5 only bears a small amount of sand, avoiding the large amount of sand from sticking the sucker rod, and greatly increasing the success rate of opening the well. After the ground fault is eliminated, the well is directly opened, and the well is successfully opened for normal production. If it is not successful, a cement truck is connected to perform bidirectional circulating well washing through the casing and hollow rod plug, the washing fluid can enter the oil pipe through the hollow rotor, or enter the oil pipe through the hollow rod for well washing, and the sand on each sand prevention joint 5 in the oil pipe is washed out to remove the sand sticking. The well is opened to resume normal production.

[0032] Example 4

[0033] When the pump is down, a sand prevention joint 5 is connected every 400 meters of the oil pipe. During normal production, the liquid in the well is transmitted upwards from each chamber of the screw pump, and when the pressure in the oil pipe is too high, the liquid breaks through the sand prevention joint 5 to move to the wellhead for normal production. According to the current card of the screw pump, if the current abnormally rises, the well can be directly washed, and the abnormal resistance in the well is removed in advance. When the screw pump on the ground fails, the fine sand carried by the liquid in the oil pipe every 400 meters will slowly settle on the sand prevention joint 5, so that the fine sand carried by the liquid in the entire wellbore can be settled on each sand prevention joint 5 in stages, preventing the fine sand from being completely settled above the screw pump stator 7, and each sand prevention joint 5 only bears a small amount of sand, avoiding the large amount of sand from sticking the sucker rod, and greatly increasing the success rate of opening the well. After the ground fault is eliminated, the well is directly opened, and the well is successfully opened for normal production. If it is not successful, a cement truck is connected to perform bidirectional circulating well washing through the casing and hollow rod plug, the washing fluid can enter the oil pipe through the hollow rotor, or enter the oil pipe through the hollow rod for well washing, and the sand on each sand prevention joint 5 in the oil pipe is washed out to remove the sand sticking. The well is opened to resume normal production.

[0034] Example 5

[0035] When the pump is down, a sand prevention joint 5 is connected every 25 meters of the oil pipe. During normal production, the liquid in the well is transmitted upwards from each chamber of the screw pump, and when the pressure in the oil pipe is too high, the liquid breaks through the sand prevention joint 5 to move to the wellhead for normal production. According to the current card of the screw pump, if the current is abnormally high, the well can be directly washed, and the abnormal resistance in the well is removed in advance. When the screw pump on the ground fails, the fine sand carried by the liquid in the oil pipe every 25 meters will slowly settle on the sand prevention joint 5, so that the fine sand carried by the liquid in the entire wellbore can be settled on each sand prevention joint 5 in stages, preventing the fine sand from being completely settled above the stator 7 of the screw pump as in the past, and each sand prevention joint 5 only bears a small amount of sand, avoiding the large amount of sand from sticking the sucker rod, and greatly increasing the success rate of opening the well. After the ground fault is removed, the well is directly opened, and if the opening is successful, the well is directly put into normal production. If it is not successful, a cement truck is connected to perform bidirectional circulation washing through the casing and the hollow rod plug, the washing fluid can enter the oil pipe through the hollow rotor or the hollow rod to wash out the sand on each sand prevention joint 5 in the oil pipe and remove the sand sticking.

[0036] Example 6

[0037] When the pump is down, a sand prevention joint 5 is connected every 25 meters of the oil pipe. During normal production, the liquid in the well is transmitted upwards from each chamber of the screw pump, and when the pressure in the oil pipe is too high, the liquid breaks through the sand prevention joint 5 to move to the wellhead for normal production. According to the current card of the screw pump, if the current is abnormally high, the well can be directly washed, and the abnormal resistance in the well is removed in advance. When the screw pump on the ground fails, the fine sand carried by the liquid in the oil pipe every 25 meters will slowly settle on the sand prevention joint 5, so that the fine sand carried by the liquid in the entire wellbore can be settled on each sand prevention joint 5 in stages, preventing the fine sand from being completely settled above the stator 7 of the screw pump as in the past, and each sand prevention joint 5 only bears a small amount of sand, avoiding the large amount of sand from sticking the sucker rod, and greatly increasing the success rate of opening the well. After the ground fault is removed, the well is directly opened, and if the opening is successful, the well is directly put into normal production. If it is not successful, a cement truck is connected to perform bidirectional circulation washing through the casing and the hollow rod plug, the washing fluid can enter the oil pipe through the hollow rotor or the hollow rod to wash out the sand on each sand prevention joint 5 in the oil pipe and remove the sand sticking. The well is opened and put into normal production.

[0038] The above examples are only used to illustrate and describe the present application, and are not intended to limit the present application to the scope of the described examples. Furthermore, those skilled in the art can understand that the present application is not limited to the above examples, and more variations and modifications can be made according to the teachings of the present application, which all fall within the scope of the present application.

Claims

1. A method of unjamming a sand-jammed sand control screw pump for use in an oilfield production well, the method comprising: The steps of the method are as follows: S1. The tubing (4) is connected with a sand prevention joint (5) at intervals; S2. During normal production, the liquid in the well is transmitted upwards from each chamber of the screw pump, and when the pressure in the tubing is too high, the liquid breaks through the sand prevention joint (5) and moves to the wellhead for normal production; S3. The current card is observed, and if the current abnormally rises, the well is washed directly, and the abnormal resistance in the well is removed in advance; S4. When the screw pump on the ground fails, the fine sand carried by the liquid in each section of the tubing (4) will slowly settle on the sand prevention joint (5), so that the fine sand carried by the liquid in the entire wellbore can be classified and settled on each sand prevention joint (5), preventing the fine sand from being completely settled above the screw pump stator (7) as before, and each joint only bears a small amount of sand settlement, avoiding the large amount of sand settlement from sticking the sucker rod and increasing the success rate of opening the well; S5. After the ground fault is removed, the well is opened directly, and the well is successfully opened for normal production; S6. If it is not successful, a cement truck is connected to perform bidirectional circulation through the tubing (4) and the hollow rod plug (1) Washing well, the washing fluid can enter the tubing (4) through the hollow rotor (8) or enter the tubing (4) through the hollow rod (3) for washing well, and the sand settled on each sand prevention joint in the tubing (4) is washed out to remove the sand sticking; S7. The well is opened for normal production. The screw pump is provided with a hollow rod (3), the top end of the hollow rod (3) penetrates through the ground driving device (2) and is connected with the hollow rod plug (1), the bottom end of the hollow rod (3) is connected with the screw pump hollow rotor (8) through the hollow rod inner turning joint (6); the outer side of the hollow rod (3) is provided with the tubing (4), and the tubing (4) and the hollow rod (3) are provided with the sand prevention joint (5); the outer side of the screw pump hollow rotor (8) is provided with the screw pump stator (7), and the lower side of the tubing (4) is provided with the tubing anchor (9). In step S1, the tubing (4) is connected with a sand prevention joint (5) at intervals of 50-100 meters. In step S1, the tubing (4) is connected with a sand prevention joint (5) at intervals of 50-100 meters.

2. The method of the claim 1, wherein the method is characterized by, The pump depth is 1000 meters, the sand column in the tubing is 10m, and each sand prevention joint 5 bears a sand column of 0.5m.

3. The method of the claim 1, wherein the method is characterized by, ​ 4. The method of the claim 3, wherein the method is characterized by, ​

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