Thickness-controllable thickened oil anti-drag liquid ring generator suitable for bent pipe

Abstract

The invention relates to a thick oil anti-drag liquid ring generator suitable for a bent pipe and controllable in thickness. The device is composed of a straight pipe, a bent pipe, a reducing pipe, an annular titanium steel sheet, a strap, a bolt, a nut, a multi-layer flow guide ring, a differential pressure transmitter and a data real-time acquisition system. The device can control the thickness of a lubricating layer in the thickened oil pipe transportation resistance reduction process, and meanwhile, the stability of the flowing state of a center thickened oil-liquid ring after the center thickened oil-liquid ring passes through a bent pipe under different lubricating layer thicknesses can be guaranteed. Wherein the thickness of the liquid ring can be controlled by tightening or expanding the annular titanium steel sheet by screwing the bolt, so that the gap between the reducing pipe and the annular titanium steel sheet is increased or reduced, the stability of the liquid ring can be ensured by a plurality of layers of flow guide rings, and the controllability of the thickness of a lubricating layer and the stability of flowing through the bent pipe are ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of heavy oil pipeline transportation, and relates to a device capable of controlling the thickness of a lubricating layer during the heavy oil lubrication and drag reduction process and ensuring that a liquid ring stably passes through a curved pipe. Background Art

[0002] As conventional oil resources become increasingly depleted, unconventional heavy crude oil will be a strategic replacement resource for global oil and gas development in the 21st century. However, the high density, high viscosity and low fluidity of heavy oil bring great difficulties and challenges to its extraction and transportation, and usually require specific methods to reduce flow resistance. Conventional methods for heavy oil gathering and transportation are mainly heating, dilution and upgrading, but they generally have limitations such as large processing volume, large energy consumption and high operating costs. At present, heavy oil liquid ring transportation is considered to be one of the most economical, energy-saving and efficient means of reducing heavy oil flow resistance, which can effectively improve transportation efficiency.

[0003] Liquid ring conveying mainly injects lubricating liquid into the liquid ring generator to form a lubricating layer to isolate the contact between the heavy oil and the pipe wall. However, the thickness of the liquid ring has a great influence on the drag reduction effect of the heavy oil. The optimal liquid ring thickness is different for different heavy oil types, flow rates, pipe diameters or temperatures, and the existing liquid ring generator cannot effectively adjust it. Therefore, how to adjust the thickness of the liquid ring is the primary consideration.

[0004] At the same time, due to environmental and geological factors, buried heavy oil pipelines cannot remain completely straight. When the heavy oil-liquid ring flows through the bend, the wall will force the flow direction to change, making it difficult for the liquid ring to stabilize, and the transportation efficiency is greatly reduced. Ensuring the stability of the liquid ring when it flows through the bend is also the key to achieving lubrication and drag reduction in pipeline transportation of heavy oil.

[0005] Therefore, the present invention designs a thick oil drag reducing liquid ring generator which is suitable for pipe bending and has controllable thickness and can be used for experimental research or field application. Summary of the invention

[0006] The present invention aims to provide a thick oil drag reducing liquid ring generator which is suitable for pipe bending and has controllable thickness, which can adjust the thickness of the lubricating liquid ring transported by the thick oil pipeline and ensure that the liquid ring can stably pass through the pipe bending.

[0007] To achieve the above functions, the technical method of the present invention is as follows:

[0008] A thick oil drag reducing liquid ring generator suitable for curved pipes with controllable thickness. The supporting device consists of a straight pipe, a curved pipe, a reducing pipe, an annular titanium steel sheet, a hoop, bolts, nuts, a multi-layer guide ring, a differential pressure transmitter, and a real-time data acquisition system. The reducing pipe, the straight pipe and the curved pipe are connected together to form a test pipe section. The straight pipe section is equipped with a differential pressure transmitter, which is connected to the real-time data acquisition system to record the pressure drop changes in the pipe at all times; there is a circular hole on each side of the reducing pipe, the side circular hole B is connected to the oil pipeline, and the upper circular hole A is connected to the lubricating liquid pipeline.

[0009] A variable-diameter oil distribution ring is installed inside the reducer, which consists of a hoop, an annular titanium steel sheet, bolts and nuts. The hoop is in the shape of an elongated rectangular parallelepiped with no edges and corners, and there is a long gap on the elongated surface. The annular titanium steel sheet passes through the middle. Three threaded holes are penetrated below the long gap, and three bolts are inserted respectively. The left and right bolts clamp the annular titanium steel sheet, and the middle bolt can fix the whole on the reducer. Nuts are installed on the top of the three bolts to prevent the bolts from falling. There are multiple slots on both sides of the annular titanium steel sheet for engaging with the threads of the bolts; one side of the annular titanium steel sheet is concentric with the circular hole B on the side of the reducer, and the diameter is always larger than the circular hole B, but always smaller than the minimum diameter of the reducer.

[0010] The multi-layer guide ring has the same bending angle as the elbow and is fixed at the center of the elbow. The multi-layer guide ring is composed of small curved rings of different diameters. All curved rings have the same shape and the same axis. When the central heavy oil-liquid ring flows through the elbow, the multi-layer guide ring can separate the heavy oil and the liquid ring. After the flow passes through the elbow, it can re-form the flow state of the central heavy oil-liquid ring when it converges. At the same time, when the thickness of the liquid ring changes, the structural design of the multi-layer circular ring can still ensure that the liquid ring and the heavy oil are fully separated when flowing through the elbow.

[0011] The annular titanium steel sheet is a composite material of titanium and steel, which has good flexibility. All other devices are made of stainless steel.

[0012] By using the thick oil drag-reducing liquid ring generator suitable for curved pipes and with controllable thickness, the thickness of the drag-reducing lubricating layer of the thick oil pipeline can be controlled, and the lubricating layer can be ensured to pass through the curved pipe stably. In order to determine the optimal thickness of the drag-reducing liquid ring for pipeline transportation under different thick oil types and flow rates, the lubricating liquid is first injected from the circular hole A, and the lubricating liquid flows through the gap between the reducer and the annular titanium steel sheet and then flows into the straight pipe. The reducer can accelerate the flow of the liquid and provide a certain centrifugal force to ensure the stability of the shape of the liquid ring. After the differential pressure transmitter measures that the pressure drop of the lubricating liquid is stable, the thick oil flows from the circular hole B into the annular titanium steel sheet and further into the straight pipe. After the overall pressure drop is stable, the three bolts on the hoop are screwed at the same time, and the threads of the bolts on the left and right sides are engaged with the card slots, which can tighten or expand the annular titanium steel sheet. The middle bolt is used to control the position of the annular titanium steel sheet so that its side is always concentric with the circular hole B of the reducer. The three bolts are all extended to the outside of the reducer and connected with the reducer spiral seal. When the annular titanium steel sheet is tightened, the flow gap of the lubricating liquid increases and the liquid ring becomes thicker. When the annular titanium steel sheet is expanded, the liquid ring becomes thinner, thereby achieving controllable thickness of the liquid ring. When the annular titanium steel sheet is adjusted to a certain size, the pressure drop of the differential pressure transmitter is the smallest, and this is the optimal thickness of the lubricating and drag-reducing liquid ring for heavy oil pipeline transportation. When the central heavy oil-liquid ring flows through the elbow, the heavy oil flows into the annular gap at the center or near the center of the multi-layer guide plate, and the lubricating liquid flows into the annular gap on the outside of the multi-layer guide plate, thereby achieving separation of the heavy oil and the lubricating liquid. After flowing out of the multi-layer guide plate, the heavy oil and the lubricating liquid are still in the center of the pipeline and the side of the pipe wall respectively, and the flow state of the central heavy oil-liquid ring can still be guaranteed, thereby effectively avoiding the failure of the lubricating liquid after flowing into the elbow.

[0013] The present invention adopts the above technical solution and has the following advantages:

[0014] 1. When lubricating and reducing drag in heavy oil pipeline transportation, different types of heavy oil, oil flow rates, pipe diameters, etc. require different thicknesses of lubricating liquid. The present invention can adjust the thickness of the liquid ring to ensure that the optimal thickness can be adjusted under different conditions.

[0015] 2. The diameter of the reducer is continuously reduced. When the lubricating liquid flows through it, the liquid flow rate can be increased, thereby improving the efficiency of liquid ring formation. At the same time, the reducer can provide a certain centrifugal force for the liquid, making the liquid ring more stable.

[0016] 3. When the central thick oil-liquid ring flows through the elbow, the liquid ring is easily damaged, thereby rendering the lubrication and drag reduction ineffective. The present invention can ensure the stability of the liquid ring after flowing through the elbow, thereby greatly improving the transportation efficiency and is expected to be applied in experiments or on-site. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a cross-sectional view of the center of the device;

[0018] Figure 2 It is a three-dimensional diagram of the whole device;

[0019] Figure 3 It is a three-dimensional picture of a ring-shaped titanium steel sheet;

[0020] Figure 4 It is a stereogram of a multi-layer guide ring;

[0021] Figure 5 It is a stereoscopic diagram of the connection of the band, bolts and nuts;

[0022] Figure 6 A three-dimensional diagram of a variable diameter oil distribution ring connected by a hoop and an annular titanium steel sheet.

[0023] Among them: 1. Bend; 2. Straight pipe; 3. Reduced pipe; 4. Annular titanium steel sheet; 5. Hoop; 6. Round hole A; 7. Round hole B; 8. Bolts on both sides of the hoop; 9. Bolts in the middle of the hoop; 10. Annular gap of the multi-layer guide plate; 11. Connecting block for fixing the multi-layer guide plate and the bent pipe; 12. Slot; 13. Long gap connecting the hoop and the annular titanium steel sheet; 14. Differential pressure transmitter; 15. Real-time data acquisition system; 16. Nut; 17. Multi-layer guide ring. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings.

[0025] A thick oil drag reducing liquid ring generator suitable for curved pipes with controllable thickness. The matching device is composed of a straight pipe, a curved pipe, a reducing pipe, an annular titanium steel sheet, a hoop, bolts, nuts, a multi-layer guide ring, a differential pressure transmitter, and a real-time data acquisition system. The curved pipe (1), the straight pipe (2) and the reducing pipe (3) are connected together to form the matching device. Figure 2 The straight pipe section is equipped with a differential pressure transmitter (14), which is connected to a real-time data acquisition system (15) to record the pressure drop change in the pipe at all times; the reducing pipe has a circular hole on both sides, the side circular hole B (7) is connected to the oil delivery pipe, and the upper circular hole A (6) is connected to the lubricating liquid delivery pipe.

[0026] A variable diameter oil distribution ring is installed inside the reducer. Figure 6As shown, the hoop is composed of a band (5), an annular titanium steel sheet (4), a middle bolt (9) of the band, bolts (8) on both sides and nuts (16). The band is in the shape of an elongated rectangular parallelepiped without edges and corners, and the elongated surface has a long gap (13). The annular titanium steel sheet passes through the middle, and three threaded holes are penetrated below the long gap, and three bolts are inserted respectively. The bolts (8) on both sides clamp the annular titanium steel sheet, and the middle bolt (9) can fix the whole on the reducer. Nuts (16) are installed on the tops of the three bolts to prevent the bolts from falling, and the three bolts extend outside the reducer and are connected to the reducer spirally. There are multiple slots (12) on both sides of the annular titanium steel sheet for meshing with the threads of the bolts; one side of the annular titanium steel sheet is concentric with the circular hole B (7) on the side of the reducer, and the diameter is always larger than the circular hole B, but smaller than the minimum diameter of the reducer.

[0027] Multi-layer guide ring (17) such as Figure 4 As shown, it is consistent with the bending angle of the elbow and is fixed at the center of the elbow. The multi-layer guide ring is composed of small curved rings of different diameters. All the curved rings have the same shape and have the same axis to form an annular gap (10). When the central heavy oil-liquid ring flows through the elbow, the multi-layer guide ring can separate the heavy oil and the liquid ring, and can re-form the flow state of the central heavy oil-liquid ring when the diversion converges through the elbow. At the same time, when the thickness of the liquid ring changes, the structural design of the multi-layer circular ring can still ensure that the liquid ring and the heavy oil are fully separated when flowing through the elbow, ensuring that the liquid ring is formed again when converging. The annular titanium steel sheet is a composite material of titanium steel, and all other devices are made of stainless steel.

[0028] By using the thick oil drag-reducing liquid ring generator suitable for curved pipes and with controllable thickness, the thickness of the drag-reducing lubricating layer of the thick oil pipeline can be controlled while ensuring that the lubricating layer passes through the curved pipe stably. In order to determine the optimal thickness of the drag-reducing liquid ring for pipeline transportation under different thick oil types and flow rates, the lubricating liquid is first injected from the circular hole A (6), and the lubricating liquid flows through the gap between the reducing pipe (3) and the annular titanium steel sheet (4) and then flows into the straight pipe. The reducing pipe can accelerate the flow of the liquid and provide a certain centrifugal force to ensure the stable formation of the liquid ring. After the differential pressure transmitter (14) detects that the pressure drop of the lubricating liquid is stable, the heavy oil flows from the circular hole B (7) into the annular titanium steel sheet and further into the straight pipe (2). After the pressure drop is stable, the three bolts on the hoop are screwed at the same time, and the threads of the bolts (8) on the left and right sides are engaged with the slots (12), so that the annular titanium steel sheet (4) can be tightened or expanded. The middle bolt (9) is used to ensure that the annular titanium steel sheet is in the center of the reducer (3) so that its side is always concentric with the circular hole B (7) of the reducer. When the annular titanium steel sheet is tightened, the flow gap of the lubricating liquid increases and the liquid ring becomes thicker. When the annular titanium steel sheet is expanded, the liquid ring becomes thinner, thereby achieving controllable liquid ring thickness. When the annular titanium steel sheet is adjusted to a certain size, the pressure drop of the differential pressure transmitter (14) is the smallest, and this is the optimal thickness of the lubricating drag reduction liquid ring for heavy oil pipeline transportation. When the central heavy oil-liquid annular flow passes through the elbow, the heavy oil flows into the annular surface gap (10) at the center or near the center of the multi-layer guide plate, and the lubricating liquid flows into the annular surface gap on the outer side of the multi-layer guide plate, thereby achieving separation of the heavy oil and the lubricating liquid. After flowing out of the multi-layer guide plate, the heavy oil and the lubricating liquid are still in the center of the pipeline and on the side of the pipe wall respectively, and the flow state of the central heavy oil-liquid annular flow can still be guaranteed, thereby effectively avoiding lubrication failure after flowing into the elbow.

Claims

1. A thick oil drag reduction liquid ring generator suitable for pipe bends with controllable thickness, which can adjust the thickness of the lubricating liquid ring for lubrication and drag reduction of heavy oil pipelines, and ensure that the central thick oil-liquid ring flows stably through the pipe bend, characterized in that: The matching device is composed of a straight pipe, a curved pipe, a reducing pipe, an annular titanium steel sheet, a band, bolts, nuts, a multi-layer guide ring, a differential pressure transmitter, and a real-time data acquisition system; the curved pipe (1), the straight pipe (2) and the reducing pipe (3) are connected together to form the matching device; the straight pipe section is equipped with a differential pressure transmitter (14), which is connected to the real-time data acquisition system (15) and can record the pressure drop change in the pipe at all times; the reducing pipe has a circular hole on the upper and side sides, the side circular hole B (7) is connected to the oil delivery pipe, and the upper circular hole A (6) is connected to the lubricating liquid delivery pipe; a variable diameter oil distribution ring is installed inside the reducing pipe, and the variable diameter oil distribution ring is composed of a band (5), an annular titanium steel sheet (4), a band middle bolt (9), bolts (8) on both sides and nuts (16); the band is in the shape of an elongated rectangular parallelepiped without edges and corners, and the elongated surface has a long gap (13), the annular titanium steel sheet (4) passes through the long gap, and the bottom of the long gap passes through Three threaded holes are passed through, and three bolts are inserted respectively. The bolts (8) on both sides clamp the annular titanium steel sheet, and the middle bolt (9) can fix the whole on the reducing pipe. Nuts (16) are installed on the tops of the three bolts to prevent the bolts from falling, and the three bolts are extended to the outside of the reducing pipe and are connected to the reducing pipe spirally and sealed. There are multiple grooves (12) on both sides of the annular titanium steel sheet for engaging with the threads of the bolts; one side of the annular titanium steel sheet is concentric with the circular hole B (7) on the side of the reducing pipe, and the diameter is always larger than the circular hole B, but always smaller than the minimum diameter of the reducing pipe; the multi-layer guide ring (17) is consistent with the bending angle of the curved pipe and is fixed at the center of the curved pipe; the multi-layer guide ring is composed of small curved rings of different diameters, all of which have the same shape and the same axis to form an annular gap (10) and is fixed at the center of the curved pipe; the annular titanium steel sheet is a composite material of titanium steel and has good flexibility, and all other devices are made of stainless steel.

2. A thick oil drag reducing liquid ring generator suitable for pipe bending and with controllable thickness as claimed in claim 1, characterized in that: In order to determine the optimum thickness of the pipeline drag reducing liquid ring under different heavy oil types and flow rates, the lubricating liquid is first injected from the circular hole A (6), and the lubricating liquid flows through the gap between the reducing pipe (3) and the annular titanium steel sheet (4) and then flows into the straight pipe; after the differential pressure transmitter (14) measures that the pressure drop of the lubricating liquid flow is stable, the heavy oil flows from the circular hole B (7) into the annular titanium steel sheet and further into the straight pipe (2). After the overall pressure drop is stable, the three bolts on the hoop are simultaneously screwed, and the threads of the bolts (8) on the left and right sides are engaged with the grooves (12), so that the annular titanium steel sheet (4) can be tightened or expanded. The middle bolt (9) is used to ensure that the annular titanium steel sheet is in the reducing pipe (3). The center of the multi-layer guide plate is arranged so that its side surface is always concentric with the circular hole B (7) of the reducing pipe; when the annular titanium steel sheet is contracted, the flow gap of the lubricating liquid increases and the liquid ring becomes thicker, and when the annular titanium steel sheet is expanded, the liquid ring becomes thinner; the optimum lubrication thickness is determined by the minimum pressure drop measured by the differential pressure transmitter (14); when the central heavy oil-liquid ring flows through the bent pipe, the heavy oil flows into the annular surface gap (10) at the center or close to the center of the multi-layer guide plate, and the lubricating liquid flows into the annular surface gap on the outer side of the multi-layer guide plate, thereby achieving separation of the heavy oil and the lubricating liquid; after flowing out of the multi-layer guide plate, the heavy oil and the lubricating liquid are still in the center of the pipeline and the side of the pipe wall respectively, and the flow state of the central heavy oil-liquid ring can still be guaranteed.

3. A thick oil drag reducing liquid ring generator suitable for pipe bending and with controllable thickness as claimed in claim 1 is adopted, characterized in that: The inner diameter of the reducing pipe (3) is continuously reduced, which can increase the flow rate of the lubricating liquid and promote the formation of the liquid ring; and the continuous reduction of the pipe diameter can provide a certain centrifugal force for the lubricating liquid, making the liquid ring more stable.

4. A thick oil drag reducing liquid ring generator suitable for pipe bending and with controllable thickness as claimed in claim 1, characterized in that: The thickness of lubricating liquid required for different heavy oil types, oil flow rates and pipe diameters is different. By tightening the bolts (8) on both sides, the annular titanium steel sheet (4) can be reduced or expanded, and the gap between the liquid ring flowing from the reducing pipe (3) to the straight pipe (2) can be reduced or increased, thereby controlling the thickness of the liquid ring. The thickness under the minimum pressure drop is then measured by the differential pressure transmitter (14), ensuring that the best lubrication effect can be achieved under different conditions.

5. A thick oil drag reducing liquid ring generator suitable for pipe bending and with controllable thickness as claimed in claim 1 is adopted, characterized in that: When the central heavy oil-liquid ring flows through the elbow, the multi-layer guide ring can separate the heavy oil and the liquid ring, and when the heavy oil flows out of the elbow and converges, the flow state of the central heavy oil-liquid ring can be re-formed. When the thickness of the liquid ring changes, the annular gap (10) occupied by the heavy oil increases or decreases, but the structural design of the multi-layer annular gap can still ensure that the liquid ring and the heavy oil are effectively separated when flowing through the elbow, and the flow state of the central heavy oil-liquid ring is maintained.

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