A continuous casing dosing device

Abstract

This utility model discloses a continuous casing chemical dosing device, relating to the field of oilfield development technology. It includes a nitrogen cylinder, with a needle valve fixedly connected to the output end of the nitrogen cylinder. A pressure gauge is installed on one side of the needle valve, and a shut-off valve is installed on the other side of the pressure gauge. A chemical tube is installed on one side of the nitrogen cylinder, with an injection valve installed at one end. A regulating valve and a flow meter are sequentially installed on the side of the injection valve, and a check valve is installed on the side of the flow meter. A gate valve is fixedly connected to the check valve. During use, the chemical is stored in the chemical tank by a pump. The nitrogen pressure in the nitrogen cylinder drives the chemical in the tank. The nitrogen pressure in the nitrogen cylinder is always greater than the annular pressure of the casing, and the chemical pressure is also greater than the annular pressure. The chemical can be continuously added to the casing annulus at a set rate to achieve corrosion and scale prevention. This device is simple, requires no power equipment, has a low failure rate, and is inexpensive.

Description

Technical Field

[0001] This utility model relates to the field of oilfield development technology, specifically to a continuous casing chemical dosing device. Background Technology

[0002] Petroleum is a viscous, dark brown liquid, mainly composed of a mixture of various alkanes, cycloalkanes, and aromatic hydrocarbons. It is one of the main targets of geological exploration. During oilfield development, especially in water-injected oilfields, the water content in the produced fluid of oil wells continuously increases. Due to the different properties of the water in the produced fluid, downhole corrosion and scaling may occur. The most common method for preventing corrosion and scaling in oil wells is to add anti-corrosion and anti-scaling agents from the annulus. Therefore, this continuous casing chemical dosing device is required.

[0003] For example, a high gas-oil ratio wellhead chemical dosing device, as disclosed in patent publication number CN213087961U, includes a piston, a vertical working cylinder, a one-way valve, a dosing tank, and a dosing connection pipe. The piston's upward movement draws the chemical solution from the dosing tank into the vertical working cylinder. Then, the piston's downward movement forces the chemical solution into the annulus between the tubing and casing of the well. Finally, an oil pump draws the chemical solution into the tubing, thereby preventing scaling in the tubing. This dosing device uses a piston to extract and pressurize the chemical solution, precisely controlling the dosage and avoiding waste or insufficient dosage. The pressure applied solves the problem of insufficient chemical addition due to excessive well pressure. Furthermore, the reciprocating motion of the piston ensures continuous dosing.

[0004] For example, a chemical dosing device for oil wells, as disclosed in patent publication number CN109025928A, includes a back pressure valve, a pipeline at the dosing point, a metering pump, a drain pipe, a ball valve, a safety valve, a bleed valve, a dosing tank, a stirrer, and a damper. The process of dosing chemicals into an oil well from the dosing tank is as follows: First, chemicals are added to the dosing tank; second, the actuator switch is pressed, the stirrer motor rotates, and the stirrer motor drives the stirrer to agitate the dosing tank, ensuring the chemicals are evenly mixed; when the amount of chemicals to be added is small, the safety valve and the back pressure valve open, allowing the chemicals to flow from the pipeline at the dosing point to the oil well for dosing; finally, the safety valve and the back pressure valve open again, allowing the chemicals to flow from the pipeline at the dosing point to the oil well, completing the dosing process. This invention enables chemical dosing into oil wells, featuring a simple structure, convenient dosing, and ease of use. It is highly practical and can generate significant economic and social benefits.

[0005] However, during the use of the above-mentioned equipment and similar equipment, the methods of adding chemicals are periodic and continuous. Continuous addition has the best effect, but it is quite difficult to add chemicals continuously when there is pressure in the annulus. The existing technology uses continuous injection equipment, which requires matching chemical tanks, injection pumps, power equipment, etc. The equipment is numerous, complex, has a high failure rate, and high cost. Therefore, we propose a more convenient and practical continuous casing chemical dosing device to meet the usage requirements. Utility Model Content

[0006] The purpose of this invention is to provide a continuous sleeve dosing device to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, this utility model provides the following technical solution: a continuous sleeve dosing device, comprising a nitrogen cylinder, a needle valve fixedly connected to the output end of the nitrogen cylinder, a pressure gauge installed on one side of the needle valve, a shut-off valve installed on one side of the pressure gauge, a reagent tank installed on one side of the nitrogen cylinder, an injection valve installed at one end of the reagent tank, a regulating valve and a flow meter sequentially installed on one side of the injection valve, a check valve installed on one side of the flow meter, and a gate valve fixedly connected to one side of the check valve.

[0008] Furthermore, the nitrogen cylinder and the reagent container are connected by a pipeline, and a needle valve, a pressure gauge, and a shut-off valve are sequentially installed on the outer wall of the pipeline.

[0009] Furthermore, a pipe is installed at one end of the medicine tank, and an injection valve, regulating valve, flow meter, check valve and gate valve are sequentially installed on the outer wall of the pipe.

[0010] Furthermore, the needle valve, shut-off valve, injection valve, check valve, and gate valve are made of stainless steel and equipped with adjustment knobs, and the valve body surface is coated with an anti-corrosion coating.

[0011] Furthermore, a filter device is installed between the medicine tank and the injection valve to filter the medicine raw materials added to the medicine tank.

[0012] Furthermore, the outer wall of the medicine container is covered with an insulation layer to maintain the temperature of the medicine container.

[0013] Compared with the prior art, the beneficial effects of this utility model are:

[0014] In this continuous sleeve dosing device, the reagent is stored in the reagent tank by pumping during use. The reagent in the tank is driven by the nitrogen pressure in the nitrogen cylinder. The nitrogen pressure in the nitrogen cylinder is always greater than the annular pressure of the sleeve, and the reagent pressure is greater than the annular pressure of the sleeve. The reagent can be continuously added to the annular space of the sleeve at a set rate to achieve the purpose of corrosion prevention and scale prevention. The device is simple, requires no power equipment, has a low failure rate, and is inexpensive. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the continuous sleeve dosing device of the present invention;

[0016] In the diagram: 1. Nitrogen cylinder; 2. Needle valve; 3. Pressure gauge; 4. Shut-off valve; 5. Chemical tank; 6. Injection valve; 7. Regulating valve; 8. Flow meter; 9. Check valve; 10. Gate valve. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] In oilfield development, continuous casing chemical dosing devices are required. The chemical dosing device provided by this utility model is specifically designed for oil well chemical dosing operations during oilfield development. Before each use, a comprehensive inspection of the device is necessary to ensure that all components are intact and tightly connected, especially key components such as nitrogen cylinder 1, needle valve 2, and shut-off valve 4, to prevent chemical leakage or equipment failure due to component damage or loosening. During operation, close attention should be paid to the pressure changes in nitrogen cylinder 1 to ensure that the nitrogen pressure is always greater than the annulus pressure to guarantee that the chemical can be continuously and stably added to the annulus at the set rate. At the same time, the reading of pressure gauge 3 should be observed to promptly detect and address any pressure abnormalities. During adjustment, the reading of flow meter 8 should be referenced to ensure the accuracy and stability of the chemical flow rate.

[0019] like Figure 1As shown, this utility model provides a technical solution: a continuous sleeve dosing device, including a nitrogen cylinder 1, a needle valve 2 fixedly connected to the output end of the nitrogen cylinder 1, a pressure gauge 3 installed on one side of the needle valve 2, a shut-off valve 4 installed on one side of the pressure gauge 3, a reagent tank 5 installed on one side of the nitrogen cylinder 1, an injection valve 6 installed at one end of the reagent tank 5, a regulating valve 7 and a flow meter 8 sequentially installed on one side of the injection valve 6, a check valve 9 installed on one side of the flow meter 8, a gate valve 10 fixedly connected to one side of the check valve 9, and the nitrogen cylinder 1 and the reagent tank 5 connected by a pipeline. Needle valve 2, pressure gauge 3, and shut-off valve 4 are sequentially installed on the outer wall of the pipeline. One end of the reagent tank 5 is connected to a pipeline. Injection valve 6, regulating valve 7, flow meter 8, check valve 9, and gate valve 10 are sequentially installed on the outer wall of the pipeline. Needle valve 2, shut-off valve 4, injection valve 6, check valve 9, and gate valve 10 are made of stainless steel and equipped with adjusting knobs. The valve body surface is coated with an anti-corrosion coating. A filter device is installed between the reagent tank 5 and the injection valve 6 to filter the reagent raw materials added to the reagent tank 5. The outer wall of the reagent tank 5 is covered with an insulation layer to maintain the temperature of the reagent tank 5.

[0020] It is important to note that during use, the agent needs to be transported to the site using a pump-tank truck. Nitrogen cylinder 1 should be pre-filled with nitrogen to maintain a certain pressure. For the initial agent addition, connect the pump outlet of the built-in pump to injection valve 6, remove pressure gauge 3, close needle valve 2 and gate valve 10, and open injection valve 6 and shut-off valve 4 to pump a certain amount of agent into agent tank 5. Air in agent tank 5 will be expelled through shut-off valve 4. After completion, close injection valve 6, install pressure gauge 3, and open needle valve 2 and gate valve 10. Pressurized nitrogen from nitrogen cylinder 1 enters the top of agent tank 5. The agent in agent tank 5 then passes through regulating valve 7, flow meter 8, check valve 9, and gate valve 1. The annulus is injected with 0. The quantity of the agent in the agent tank 5 and the agent addition flow rate can be determined by the flow meter 8. The addition rate of the agent can be controlled by adjusting the regulating valve 7. When the quantity of the agent in the agent tank 5 needs to be replenished, the agent is transported to the site using a pump-tank truck. The pump outlet of the truck is connected to the injection valve 6. The gate valve 10 is closed, and the injection valve 6 and needle valve 2 are opened to pump a certain amount of agent into the agent tank 5 from the bottom. The nitrogen in the agent tank 5 flows back to the nitrogen cylinder 1 through the needle valve 2. After completion, the injection valve 6 is closed and the gate valve 10 is opened. The agent can be injected normally into the annulus. This device is simple, requires no power equipment, has a low failure rate, and is inexpensive.

[0021] It should be noted that a pressure sensor and a temperature sensor are installed between the flow meter 8 and the single-flow valve 9. The signal output terminals of both are connected to the PLC controller. The PLC controller adjusts the opening of the regulating valve 7 according to the real-time data to control the rate at which the reagent is added.

[0022] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles of the present invention, the scope of which is defined by the appended embodiments and their equivalents.

Claims

1. A continuous cannula dosing device comprising a nitrogen cylinder (1), characterized in that: A needle valve (2) is fixedly connected to the output end of the nitrogen cylinder (1). A pressure gauge (3) is installed on one side of the needle valve (2). A shut-off valve (4) is installed on one side of the pressure gauge (3). A reagent tank (5) is installed on one side of the nitrogen cylinder (1). An injection valve (6) is installed at one end of the reagent tank (5). A regulating valve (7) and a flow meter (8) are installed sequentially on one side of the injection valve (6). A check valve (9) is installed on one side of the flow meter (8). A gate valve (10) is fixedly connected to one side of the check valve (9).

2. A continuous cannula dosing device according to claim 1, characterized in that The nitrogen cylinder (1) and the reagent tank (5) are connected by a pipeline, and the needle valve (2), pressure gauge (3) and shut-off valve (4) are installed on the outer wall of the pipeline in sequence.

3. The continuous cannula dosing device of claim 1, wherein: The medicine tank (5) is equipped with a pipe at one end, and an injection valve (6), a regulating valve (7), a flow meter (8), a check valve (9) and a gate valve (10) are installed on the outer wall of the pipe in sequence.

4. The continuous cannula dosing device of claim 1, wherein: The needle valve (2), shut-off valve (4), injection valve (6), check valve (9) and gate valve (10) are made of stainless steel and equipped with adjustment knobs. The valve body surface is provided with an anti-corrosion coating.

5. The continuous cannula dosing device of claim 1, wherein: A filter device is installed between the medicine tank (5) and the injection valve (6) to filter the medicine raw materials added to the medicine tank (5).

6. The continuous cannula dosing device of claim 1, wherein: The outer wall of the medicine container (5) is covered with a heat insulation layer to maintain the temperature of the medicine container (5).

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