CN201835794U - Drainage and gas production simulation experiment device - Google Patents

Abstract

The utility model provides a drainage gas recovery simulation experiment device, which is used for simulating the drainage gas recovery of a coal bed gas well or other water-producing gas wells. It is composed of a reducer, a water pump, a wellhead device, a water storage device, a detection device, a casing string, a water pipe string, a drainage rod string and a drainage pump. Drainage rod string, water pipe string and casing string provide two annular spaces. While the rod pipe annulus drains water, the water jacket annulus discharges air; the physical property distribution of the water jacket annulus realizes the study of two-phase flow gas separation conditions; the reducer Integrate the power machine and the transmission system to realize the continuous adjustment of the maximum transmission ratio and stroke times, as well as the arbitrary adjustment of the discharge volume from 3 to 30m ³ /d and the submergence degree from 0 to 20m; the detection device realizes the discharge volume and dynamic liquid level Real-time monitoring of , pressure, well fluid composition and rod force; the beam balance weight adopts a split structure, and the position of the crank balance weight can be continuously adjusted to achieve better balance of the pump; it adopts a single crank, single connecting rod and sliding bearing structure , to reduce the overall size.

Description

Drainage gas recovery simulation experiment device

technical field

The utility model relates to a simulation device for drainage and gas recovery of a coal bed gas well or other water-producing gas wells, which is suitable for a rod drainage and recovery process system. the

Background technique

At present, the existing simulation experiment device is a rod-mounted device composed of a power machine, a pumping unit, an oil pipe, a sucker rod, and an oil pump, and is used for lifting the liquid in an oil well. Inject a certain amount of liquid in the air, start the power unit, and convert the rotary motion of the power machine into the up and down reciprocating motion of the suspension point through the pumping unit, so as to approximate the downhole conditions in oil well production, and complete the well fluid flow rate, solid particle settlement and rod Testing and analysis of stress situations. However, these simulation devices do not provide another annular space composed of tubing and casing, and cannot simulate the drainage of the annulus of the rod and tubing, and the gas drainage conditions of the annulus of the oil and casing, so they are not suitable for the experimental simulation of water-producing gas wells; moreover, Only a certain amount of liquid can be injected into the annulus of the rod and pipe, but the annulus of the pipe and pipe of the actual well is full of well fluid, and there is also a certain degree of submergence in the annulus of the oil casing outside, and the height of the degree of submergence varies with the progress of drainage. At the same time, the rod string and pipe string are usually only 1-3m, which cannot complete the simulation of the change of the dynamic liquid level and submergence height; in addition, the pumping unit has a certain number of strokes, which cannot be adjusted continuously. The liquid volume is constantly changing, and it is necessary to realize stepless speed regulation to meet the liquid discharge requirements. the

Utility model content

In order to overcome the shortcomings of the existing rod lifting simulation experiment device, the purpose of this utility model is to provide a drainage and gas recovery simulation experiment device. It is an experimental system with real-time adjustment of fluid displacement within a certain height and within a certain range, and can realize real-time monitoring of fluid displacement, dynamic fluid level, well pressure, well fluid composition and rod force, and stroke times at a large Continuously adjustable within the range of experimental requirements. the

The technical scheme adopted by the utility model to solve the technical problem is to develop a pole column and pipe column with a height of 30m, a discharge volume of 3-30m ³ /d, and the measurement of displacement, pressure, gas content and pulverized coal content. The system's drainage and gas recovery simulation experiment device includes a spiral bevel gear reducer, a water pump, a wellhead device, a water storage device, a detection device, a casing string, a water pipe string, a drainage string and a drainage pump. The pump barrel of the drainage pump is lowered below the dynamic liquid level in the well with a water pipe string, and a fixed valve that can only be opened upward is installed at the lower part of the pump barrel. The top is equipped with a swimming valve that can only be opened upwards. A four-bar mechanism composed of a single crank, a single connecting rod, a beam and a bracket is installed on one side of the reducer. The beam acts on the bracket through the beam support, and drives the polished rod of the wellhead through the donkey head connection to realize suspension. The up and down reciprocating movement of the point, the polished rod is located at the uppermost end of the drainage rod, and is suspended on the head of the donkey through the wellhead device, and the drainage rod is used to drive the plunger of the drainage pump, and the liquid in the well flows through the drainage rod and the water pipe The rod pipe annular space between the strings is lifted to the wellhead, and the gas is discharged from the water jacket annular space between the water pipe string and the casing string under the action of pressure difference.

The water pump is the main body of the ground driving device, which is used to change the rotary motion of the power machine into the reciprocating motion of the drainage rod. According to the different operating conditions and stroke requirements of coalbed methane wells, the structural size of the four-bar mechanism of the pump is optimized to meet the needs of different working conditions. The pump adopts a compound balance method. The crank balance adopts a single crank structure. The entire handle body is cast from pig iron. The position of the balance weight can be adjusted continuously to achieve a better balance of the pump; The split structure is adopted, that is, the whole balance weight is composed of several casted single balance weights, and is fixed to the end of the beam by two long bolts passing through all the balance weights. When performing balance adjustment, only need to add or Reducing the number of balance blocks can make the water pump in a better balanced state, which is of great significance for realizing energy saving and reducing the labor intensity of workers to adjust the balance blocks. The crank of the water pump is connected with the connecting rod through the crank pin. The connecting rod adopts channel steel structure and is connected with the beam through the beam support. Composed of sub-bearing bushes and connecting bolts, it has good lubrication performance and replaces the current more complicated support structure; the main body of the beam is made of I-shaped steel structure, and the main body of the donkey head is welded by channel steel, which can further simplify the structure of the pump The traveling beam acts on the support through the supporting of the traveling beam, and the front and rear legs of the support as well as the cross brace and diagonal brace are all welded by angle steel, and the structure is simple. The base of the pump is designed with a guide rail device, which is welded by three steel plates, and the three steel plates form a groove structure, which is matched with the lower end surface of the I-beam used for the main body of the base; at the same time, one end of the base is designed with a screw And the handle, the screw adopts trapezoidal thread structure, and the base moves axially along the guide rail by rotating the handle, which is convenient for the pump to get out of the wellhead position during well workover operations. the

The power machine provides power for the water pump, and the spiral bevel gear reducer is used as the power machine and the infinitely variable transmission system of the water machine. One side of the reducer is equipped with a single crank and a single connecting rod structure, which is fixed by a frame structure welded by channel steel. on the base of the pump. The speed reducer integrates the motor, governor and reducer. The governor is equipped with a speed regulating handle. By rotating the handle, the stroke frequency can be continuously adjusted within a large transmission ratio range. Moreover, the output torque of the speed reducer changes according to the adjusted strokes, which can meet the output torque requirements of the small water pump. the

The wellhead device is composed of sealing box, tee, water pipe head, cross, casing head and wellhead support from top to bottom. The upper and lower ends of the wellhead support are designed with disc-shaped flanges, which are fixed to the ground by anchor bolts. The casing head adopts a double-piece flange made of plastic material, which is used to fix the top of the casing string. The casing head is connected with the spool and the wellhead support through stud bolts. The port of the three-way is connected with the water outlet pipe, and one port of the four-way is connected with the water inlet pipe, and the other port is connected with the air outlet pipe, and can also be connected with the air inlet pipe. The water pipe head is used to fix the top of the water pipe column, and the two ends of the tee and cross adopt a double-piece flange structure and are connected together by bolts. The sealing box includes three parts: the gland, the sealing chamber and the bottom plate. The outer end is designed with a flange structure. The gland and the sealing chamber are connected by bolts, and the gland is moved axially by adjusting the bolt to compress the sealing chamber. The packing realizes the sealing between the wellhead device and the polished rod; the packing can be new or old ordinary V-belts, which are spirally wound around the polished rod and placed in the sealing chamber. In the experiment, the liquid in the well is transported through the annulus of the rod pipe, discharged from the port of the tee, and stored in the water storage tank, and then injected into the annulus of the water jacket through a port of the cross to inject an equal volume of well fluid with the same composition to replenish in time The discharged well fluid, thereby realizing the recycling of the well fluid, maintains a certain degree of submergence, and the height of the dynamic liquid level remains unchanged. The other port of the cross is used to discharge and supplement the gas in the annulus of the water jacket, and is installed with a pressure Meter, real-time measurement of wellhead pressure value. Gaskets with a thickness of 3 to 5 mm are installed between the casing head, spool, water pipe head and tee to achieve sealing and facilitate adjustment when the length of the pipe string is redundant. the

The water storage device is used to store well fluid and replenish well fluid to the well in time, including water storage tank, tank base, water inlet pipe, water outlet pipe and water valve. The water storage tank is welded by steel plates, and the middle part is reinforced by angle steel circumferential welding. The main body of the tank base is made of channel steel and fixed on the ground with anchor bolts. The outlet pipe and the water inlet pipe are connected by a water pipe, a reducing joint, a 90° elbow and a tee. One end of the outlet pipe is connected to the water storage tank, the other end is connected to the wellhead tee, and one end of the water inlet pipe is connected to the water storage tank. connection, and the other end is connected to the wellhead cross. Water valves are installed on both the outlet pipe and the water inlet pipe to control the liquid flow rate, thereby simulating the change of the liquid discharge in the well. In addition, changing the well fluid flow rate in the water inlet pipe and the water outlet pipe can adjust the dynamic fluid in the water jacket annulus. surface height. the

The drainage rod column is used for the connection between the water pump and the downhole drainage pump, including four parts: the polished rod, the drainage rod, the coupling and the reducing short rod. The discharge rod is a steel rod with a solid circular section, and the two ends are processed with external threaded joints, unloading grooves and wrench square necks. The external threaded joints use ordinary threads to connect with the coupling; the shape of the unloading groove is the same as that of the relief groove , used to reduce the stress concentration caused by thread and cross-section changes; the square neck of the wrench is composed of two parallel wrench planes, which are used to clamp the discharge rod when loading and unloading the discharge rod. The polished rod is a special drainage rod on the upper part of the drainage rod. Its structure and size are the same as those of the drainage rod, but it needs to be precisely processed. The surface of the rod is polished. The deviation of straightness within any 305mm length on the rod body shall not be greater than 1.5mm, so as to realize the cooperation with the wellhead sealing box and seal the wellhead. The coupling adopts a steel pipe with a circular cross-section. The outer wall of the pipe has a wrench square neck, and the inner wall is processed with internal threads to match the external thread joints of the polished rod and the drainage rod. The two ends of the reducing short rod are processed with external threaded joints of different sizes, the upper end of which is connected with the collar at the lower part of the drainage rod column, and the lower end is connected with the plunger of the drainage pump. the

The water pipe string and the drainage rod string form an annular space of the rod pipe, which is used to transport liquid and drain water, including water pipes, upper joints, lower joints, tail pipes, body and bottom end cover. The water pipe, the upper joint and the lower joint are all made of transparent plastic. After the upper joint and the lower joint are connected together by threads, the two ends are connected with the water pipe; The lower part is connected in sequence, and the lower end is anchored together with the bottom end cover and the main body through the pin shaft. Screen holes of different diameters are processed on the pipe wall to facilitate the well fluid to carry solid particles of different sizes through; the main body is located at the bottom of the water pipe string , both ends adopt flange structure, the upper end is fixed on the base through double-threaded threads, and is sealed with a gasket; the upper end of the bottom end cover adopts a columnar structure, which is placed in the inner wall of the tail pipe, and the upper end of the end cover is processed with five annular grooves , used to place a ○-shaped rubber sealing ring to realize the sealing of the tailpipe at the bottom of the well. The lower end of the end cover is a flange structure, which is connected with the bottom of the body through bolts and sealed with a gasket. the

The casing string and the water pipe string constitute the annular space of the water jacket, and the casing string includes four parts: casing, Yuling, bottom hole tee and sealing box. The casing is made of transparent plastic pipes, which are connected together by joints; the bottom hole tee is located at the bottom of the casing string, and its port is connected with the gas inlet pipe. The sealing bottom plate and the sealing body are connected, and the gasket is used to realize the sealing. When the bottom of the well is blocked by sand, coal powder and coal gangue, the deposited solid particles can be cleaned from the port of the tee at the bottom of the well; the sealing box includes a bushing , sealing body, sealing packing and sealing bottom plate, the sealing packing of the sealing box at the bottom of the casing string is put into the sealing chamber from the bottom of the liner pipe, and the rectangular sealing ring is adopted. Its unique cross-sectional shape makes it have good working performance. performance and radial compensation capability; the bushing adopts a columnar structure, and is inserted into the sealing chamber from the bottom end of the liner pipe to squeeze the bushing and compress the sealing packing to realize the sealing between the casing and the water pipe at the bottom of the well; the sealing bottom plate An annular groove is processed, and a ○-shaped rubber sealing ring is placed to further strengthen the seal between the end face of the tee and the sealing box; both ends of the sealing bottom plate and the sealing body adopt disc-shaped flanges, and the lower end of the sealing body passes through the double-head Bolts are connected with the bottom plate; the bottom plate is fixed on the end face of the well bottom through a frame structure welded by channel steel. In the experiment, the distribution of physical properties of the annular space of the water jacket is the gas column section, the gas-water two-phase liquid column section, and the water column section from top to bottom. While water is produced in the annular space of the rod tube, gas is produced in the annular space of the water jacket. . the

The drainage pump is composed of pump barrel assembly, plunger assembly and fixed valve assembly. The pump barrel assembly includes water pipe couplings, extension joints, pump barrels and pump barrel couplings. The water pipe couplings and pump barrel couplings are made of steel pipes with circular cross-sections. The inner wall is processed with internal threads. The water pipe couplings are directly connected to the underground The lower end of the water pipe string fixes the drainage pump on the water pipe string; the upper end of the pump barrel coupling is connected and sealed with the extension joint, and the lower end is connected and sealed with the pump barrel; both ends of the pump barrel have external threads, and the surface of the inner wall is electroplated. Then it is precisely machined, has good wear resistance and corrosion resistance, and is matched with the plunger with high precision; the upper and lower lengthened joints are one piece each, and are respectively connected to the couplings of the pump barrel at both ends. The plunger assembly includes a plunger and a floating valve assembly; wherein, the floating valve assembly is located at the upper end of the plunger, including a floating valve cover, a floating valve ball and a valve seat; the floating valve cover passes through threads at both ends, and the upper part It is connected with the variable-diameter short rod, and the lower part is connected with the plunger. The floating valve ball and the valve seat are installed inside the valve cover. The sealing performance of the floating valve ball and the valve seat is high; in the experiment, the floating valve can only be opened upwards. , so that the well fluid in the lower part of the plunger in the pump barrel can be discharged into the annulus of the rod tube in time. The fixed valve assembly is located at the lower end of the pump barrel, including a fixed valve cover, a fixed valve ball and a valve seat. The fixed valve cover is fixed by a locking device, and the fixed valve ball and valve seat are placed in the fixed valve cover. In the experiment, the fixed valve can only be opened upwards to ensure that the liquid in the annular space of the water jacket flows into the pump barrel through the tailpipe. the

The detection device is used to complete the real-time collection, analysis and processing of the data in the experiment. Attach the strain gauges of the wireless dynamic stress meter to the upper ends of the rods of the pump and the upper end of the drainage rod to test the stress on the rods, and use the wireless dynamic stress and acceleration tester to measure the load and displacement of the pump, the stress and strain of the rods and Crank shaft torque, etc., in order to improve the design and calculation of rod pump equipment; clamp the current transformer to the power line of the reducer, and use the beam pump pump sub-node efficiency analysis and balance state tester to test the efficiency and balance weight of each node Adjustment and motor power, etc.; use laser rangefinder and tachometer to measure the displacement and speed of the suspension point and plunger, and test the dynamic performance of the equipment; Transmitters to measure wellhead and bottom well pressure values to detect the relationship between pressure and production capacity; install an electromagnetic flowmeter on the water inlet pipe of the water storage device to measure the liquid flow rate and discharge volume in the pipe; the liquid level transmitter is installed in the water At the bottom of the well below the dynamic liquid level in the collar air, measure the liquid level, monitor the changes in the dynamic liquid level and submergence; the data collector and the instrument with a single input channel are connected through a serial port, one end is connected to the detection equipment, and the other end is connected to the computer. All the data collected by the testing equipment are input into the computer in time by the data collector and single input channel instrument, and after the data is analyzed and fed back, the corresponding processing is carried out. the

The beneficial effect of the utility model is that two annular spaces are provided by adopting the drainage rod string, the water pipe string and the casing string, and at the same time realizing the drainage of the rod pipe annular space, the on-site simulation of the water jacket annular air outlet; the water jacket annular space is automatically The on-site simulation of the physical property distribution of the gas column, gas-water two-phase liquid column and water column from top to bottom can complete the experimental research on the time and conditions for the sufficient separation of gas in the two-phase flow; the infinitely variable transmission system composed of a spiral bevel gear reducer, Realize large transmission ratio and continuous adjustable stroke times, combined with electromagnetic flowmeter, realize real-time measurement of liquid displacement and on-site simulation of low displacement at 3-30m ³ /d, and complete the movement of sand, coal powder and coal coke Experimental research on characteristics and discharge conditions; the total height of the pipe string is 30m, through the liquid level transmitter, the real-time measurement of the dynamic liquid level in the annulus of the water jacket and the on-site simulation of the arbitrary adjustment of the submergence degree within the range of 0-20m are realized, and the low submergence is achieved Experimental research on the opening conditions of pump valves at high temperature; installation of pressure transmitters, real-time measurement of wellhead pressure and bottom pressure, and completion of gas well dynamic analysis test research on productivity changes with pressure; wireless dynamic stress tester and laser range finder, completed Real-time measurement of suspension point load, rod stress and strain, and suspension point and plunger displacement; use the self-developed beam pump pump sub-node efficiency analysis and balance state tester to complete the simulation device's node efficiency, balance weight adjustment and motor power Real-time testing; the beam balance weight adopts a split structure, and the position of the crank balance weight can be continuously adjusted to achieve a better balance of the pump, and the base is designed with a guide rail and a rotating screw to facilitate the movement of the whole machine, so that the wellhead can be out of the well during workover Position; the use of integrated transmission system, single crank, single connecting rod and sliding bearing structure reduces the size and footprint of the whole machine and saves costs.

Description of drawings

Below in conjunction with accompanying drawing, the utility model is further described:

Fig. 1 is a front view of a typical structure of the simulation experiment device for drainage and gas recovery proposed by the utility model. the

Fig. 2 is a top view of a typical structure of the simulation experiment device for drainage and gas recovery proposed by the utility model. the

Fig. 3 is a schematic structural diagram of the water pump in the simulation experiment device for drainage and gas recovery. the

Fig. 4 is a structural schematic diagram of the wellhead device in the drainage and gas recovery simulation experiment device. the

Fig. 5 is a schematic diagram of the structure of the bottom hole assembly in the drainage and gas recovery simulation experiment device. the

In the figure, 1-drainage pump, 2-casing string, 3-water pipe string, 4-drainage rod string, 5-wellhead device, 6-detection device, 7-water storage device, 8-pumping machine, 9-reducer , 10-bracket, 11-rope hanger, 12-donkey head, 13-beam, 14-beam balance weight, 15-beam support, 16-connecting rod, 17-crank, 18-reducer base, 19- Base, 20-rail, 21-gland, 22-seal chamber, 23-bottom plate, 24-tee, 25-double flange, 26-water pipe head, 27-cross, 28-pressure transmitter, 29 -casing head, 30-wellhead support, 31-pump barrel, 32-pump barrel coupling, 33-extended nipple, 34-water pipe coupling, 35-water pipe, 36-lower joint, 37-upper joint, 38- Casing, 39-draining rod, 40-coupling, 41-you order, 42-reducing short rod, 43-moving valve assembly, 44-plunger, 45-fixed valve assembly, 46-well Bottom tee, 47-tail pipe, 48-sealed packing, 49-sealed body, 50-sleeve, 51-bottom plate, 52-body, 53-bottom end cap. the

Detailed ways

In Fig. 1, the drainage rod string 4, the water pipe string 3 and the casing string 2 are arranged sequentially from the inside to the outside, and the water pipe string 3 is used to lower the pump barrel of the drainage pump 1 below the dynamic liquid level in the well, and the drainage rod Column 4 lowers the plunger into the pump barrel from the water pipe string, and the water pipe string is lowered from the casing string 2 to form a water jacket annular space, which is used to simulate gas-water two-phase flow for gas production, and the drainage rod The rod is lowered into the column to form an annular space of the rod and pipe, which is used to transport well fluid. The polished rod at the upper end of the drainage rod is suspended on the donkey head of the pump 8 through the wellhead device 5. With the help of the four-bar linkage mechanism of the pump, the speed reducer 9 The rotational motion of the suspension point becomes the reciprocating motion of the suspension point. The power is transmitted from the ground to the downhole through the drainage rod 4, and the plunger of the drainage pump 1 reciprocates under the drive of the rod, so that the liquid in the well is transported to the tee at the wellhead through the annulus of the rod pipe, and then passed through the storage tank. The outlet pipe of the water device 7 is transported to the water storage tank for storage, and the well fluid is replenished to the well in time through the water storage tank. The liquid is transported to the cross of the wellhead through the water inlet pipe, enters the water jacket annulus, and then passes through the tail pipe and the pump string The plug enters the annulus of the rod and pipe, thereby realizing the circulation of the well fluid in the simulation experiment and the relative stability of the downhole dynamic fluid level. In addition, the reducer integrates the motor, governor and reducer to ensure the continuous adjustment of stroke times within a large transmission ratio range in the experiment; wireless dynamic stress tester, laser rangefinder, pressure transmitter, electromagnetic Detecting devices 6 such as flowmeters, liquid level transmitters, and data collectors ensure real-time collection, analysis, and processing of data in experiments. the

In Fig. 1, when repairing a well or replacing the water pipe and drainage pump model, the power of the reducer 9 should be turned off first, the gas in the annular space of the downhole water jacket should be pumped out, and the liquid in the well should be discharged from the port of the bottom hole tee 46 , unload the original pressure in the well; then unload the drainage rod 4 from the rope hanger 11; then, loosen the anchor bolts on the pump base 19, and rotate the screw through the handle to make the pump move along the guide rail 20 for a section Distance, give way to the wellhead position; at last, loosen the bolts that the sealing box in the wellhead device 5 is connected with the tee 24, and take off the sealing box. the

In Fig. 3, the reducer 9 drives the water pump 8, and a single crank 17, a single connecting rod 16 and a beam support 15 containing sliding bearings are installed on one side of the reducer, the crank 17 is connected with the lower end of the connecting rod 16 through a crank pin, and The upper end of the rod is connected with the beam support 15, the single crank 17, the single connecting rod 16, the beam 13 and the bracket 10 are sequentially connected to form the four-bar mechanism of the pump, and the beam is connected by the donkey head 12 and the rope suspension 11 to drive the wellhead Draining rods realize the up and down reciprocating movement of the suspension point. The structural size of each component has been optimized and designed, using a composite balance form of beam balance and crank balance. The beam balance weight 14 adopts a split structure, and the position of the crank balance weight can be continuously adjusted, so that the pump can reach a better balance state . The pump adjusts the stroke through the selection of the crank hole, and adjusts the stroke times through the reducer, so that the stroke can be adjusted step by step and the stroke times can be adjusted steplessly within a large range. The reducer is fixed on the pump base 19 through the reducer base 18, and the beam support 15 is used to connect the connecting rod and the beam. It adopts a split-type two-helix positive sliding bearing, and lubricates the bearing through the oil cup on the bearing cover. The design on the base 19 Guide rail 20 is arranged, and the whole water pump can be moved conveniently by rotating the screw rod through the handle. The support 10 can be fixed on the base 19 in the form of four legs with two legs at the front and two legs at the rear, or can be fixed on the base with a single leg at the front and three legs with two legs at the rear. The overall layout is more convenient and stable. Good sex. the

In Fig. 4, the sealing box is located at the top of the wellhead device 5, and is composed of a gland 21, a sealing chamber 22 and a bottom plate 23. The material is 45 steel, the gland and the sealing chamber are connected by bolts, and the packing is spirally wound around the polished rod. Into the sealing chamber 22, the adjusting bolt presses the packing through the gland 21 to generate radial force to realize the sealing of the wellhead; the two ends of the tee 24 and the cross 27 adopt the structure of double-piece flange 25, which are connected by bolts The sealing box and the upper end of the tee 24, and the tee is communicated with the annular space of the rod pipe. In the experiment, the well fluid is discharged from the port of the tee; The annular space of the water jacket is connected. In the experiment, the gas is discharged from one port of the cross, and a flowing gas column is formed in the well. By controlling the gas discharge speed, the pressure of the gas column in the well is adjusted, and a pressure transmitter 28 is installed at this port , to measure the wellhead casing pressure, and the liquid in the water storage tank is injected from another port of the cross to replenish the discharged well fluid in time; the lowermost end of the wellhead device is connected with the lower end of the cross, the casing head 29 and the wellhead support with stud bolts 30. The anchor bolts fix the entire wellhead device 5 on the ground through the flange at the lower end of the wellhead support. the

In Fig. 5, the extraction rod 39 is connected with the coupling 40 through threads to form the extraction rod column 4, the material is 45 steel, the upper end of the extraction rod column is a polished rod, and is suspended on the donkey head 12 of the water pump by means of a rope hanger 11. And cooperate with the sealing box of the wellhead device 5 to seal the wellhead, the polished rod is connected to the downhole drainage rod through the coupling 40, and the lower end of the drainage rod is threaded to connect the coupling, the reducing short rod 42 and the plunger 44 together, The plunger reciprocates up and down with the drainage rod to discharge water. The water pipe 35 is connected into the water pipe column 3 through the upper joint 37 and the lower joint 36, and forms an annular space with the drainage pole. The lower end of the water pipe string is sequentially connected with the pump barrel 31 and the tail pipe 47 through the water pipe collar 34, and the tail pipe 47 is anchored together with the body 52 and the bottom end cover 53 through the pin shaft, so that the well fluid passes through the screen of the tail pipe. The bore enters the pump barrel and through the movement of the plunger enters the rod tube annulus. The casing 38 is connected to form a casing string 2 by the order 41, forming a water jacket annular space with the water pipe string, and the gas is discharged by relying on the pressure difference in the annular space; the upper end of the casing string is fixed at the wellhead by a casing head 29 with a double-piece flange 25 structure Above, the lower end of the casing string is connected to the sealing box through the bottom hole tee 46. The sealing box is composed of a bushing 50, a sealing body 49 and a sealing bottom plate. The material is 45 steel, and the sealing packing 48 is placed into the sealing body along the liner 47. In the sealing cavity of 49, tighten the connecting bolts of the sealing body 49 and the body 52, press the sealing packing 48 through the bushing 50, generate radial force, and realize the sealing between the water pipe string and the lower end of the casing string; The sealing box and the body 52 are fixed on the bottom plate 51 together. In the experiment, the gas is charged from the port of the bottom hole tee 46 to form a gas-water two-phase flow with the liquid in the annulus of the water jacket, and the gas in the gas column section is replenished in time to maintain a certain wellhead pressure; In the case of clogging, it is necessary to open the end cover of the bottom tee 46 port, take out the deposited solid particles, clean the bottom of the well, and then cover the end cover; the solid particles are deposited in the tube of the tail pipe 47 and cause When the pump is stuck, it is necessary to loosen the connecting bolts of the body 52 and the bottom end cover 53, pull out the anchor pin, open the bottom end cover 53, clean the tail pipe 47, then cover the bottom end cover, and insert the pin , tighten the bolts. the

In Fig. 5, the pump barrel 31 of the drainage pump 1 is directly connected to the lower end of the water pipe column 3 by the water pipe collar 34 according to the designed pump hanging depth, and then connected to the tail pipe 47 through the lengthening nipple 33 and the pump barrel collar 32. The plunger 44 is lowered into the pump cylinder 31 along with the drainage rod 4. There is a set of floating valve assembly 43 on the upper end of the plunger. In addition, the fixed valve assembly 45 is fixed together with the pump cylinder by a locking device. During the upstroke, the plunger 44 goes up with the drainage rod 4, the volume of the pump barrel below the plunger increases, the pressure decreases, the floating valve closes under the action of the upper and lower pressure differences, and the fixed valve in the annular space of the water jacket It is opened under the effect of submergence, and the well fluid flows into the pump barrel through the sieve hole of the tailpipe 47 and the fixed valve hole. The outlet pipe discharges. During the downstroke, the plunger moves downward, the pressure in the pump barrel increases, the floating valve opens, the fixed valve closes, and the well fluid enters the annulus of the rod pipe above the plunger through the floating valve. The pump completes a suction cycle. As the cycle repeats, the well fluid is continuously lifted to the wellhead. the

In Fig. 5, during operation, the drainage column 4 should be disassembled first, and the drainage column 4 should be taken out from the water pipe column 3 with a lifting device. Connecting threads between the two, unload each section of the extraction rod in sequence, and finally unload the plunger 44 at the lower end of the extraction rod string; then, disassemble the water pipe string 3, and loosen the tee 24 and cross 27 in the wellhead device 5 and remove the tee, then loosen the bolts connecting the body 52 and the bottom plate 51 and pull out the pin, remove the body and the bottom end cover 53, and then use the lifting device to take out the water pipe string from the casing string 2 , the wrench clamps the clamps of the upper joint 37 and the lower joint 36, loosens the connecting thread between the two, removes each water pipe in sequence, and finally removes the pump barrel 31 and the tail pipe 47 at the lower end of the water pipe column; then, disassemble Casing string 2, loosen the connecting bolts of the sealing body 49 and the bottom hole tee 46, take out the sealing packing 48 and the bushing 50, remove the sealing box, remove the bottom plate 51, and the entire casing string is based on the casing head 29 and The fixing function of the wellhead support 30 can be in the suspended state of natural elongation; finally, clean water is injected into the casing string 2 from the wellhead to clean the pipe wall of the casing string. the

Claims (5)

1. A simulation experiment device for drainage and gas recovery, comprising a speed reducer, a water pump, a wellhead device, a water storage device, a detection device, a casing string, a water pipe string, a drainage column and a drainage pump, and the speed reducer is used as a power machine and a transmission The system, a four-bar mechanism composed of cranks, connecting rods, beams and brackets connected in sequence, realizes the up and down reciprocating movement of the suspension point. Its characteristics are: the drainage rod string, the water pipe string and the casing string are arranged in sequence from the inside to the outside. Provide two annular spaces of the rod tube and the water jacket. The physical property distribution of the water jacket annular space is the air column, the gas-water two-phase liquid column and the water column from top to bottom; a single crank and a single connecting rod are installed on one side of the reducer Supported by a beam with sliding bearings, the beam is connected through a donkey head and drives the polished rod at the wellhead; the reducer integrated with the motor, governor and reducer is used as the power machine and the infinitely variable transmission system of the experimental device, and the reducer passes through the channel steel The frame of the welded structure is fixed on the base of the pump; the end of the beam of the pump is equipped with a balance weight, which adopts a split structure and is composed of several single balance blocks. The beam support adopts a sliding bearing structure. , split bearing bush and connecting bolts, there is an oil cup for lubricating the bearing on the bearing cover, there are guide rails and screw rods on the base of the pump, the guide rail adopts a groove structure welded by three steel plates, and the I-steel end surface of the base main body Cooperate, the screw adopts trapezoidal thread, and the base moves along the guide rail by rotating the screw to let out the wellhead; the wellhead device includes a sealing box, a tee, a water pipe head, a cross, a casing head and a wellhead support, and the gland of the sealing box is connected by bolts and The sealed cavity is connected, the port of the tee is connected to the outlet pipe, one port of the cross is connected to the water inlet pipe, and the other port is connected to the air outlet pipe, and can also be connected to the air inlet pipe, and a pressure gauge is installed. The water pipe head is connected to the tee through bolts. The casing head is connected with the cross and the wellhead support through stud bolts; the water storage tank is welded by steel plates, and the middle is reinforced with circumferentially welded angle steel; the drainage column includes polished rods, drainage rods, Couplings and variable diameter short connecting rods, drainage rods and polished rods are solid steel rods with external thread joints processed at both ends, there are unloading grooves and wrench square necks on it, the couplings are made of steel pipes, the outer wall of the pipe has a wrench square neck, and the inner wall It is processed with internal threads, which match with the external threaded joints of the polished rod and the extraction rod. There are external threaded joints of different sizes at both ends of the reducing short rod, the upper end is connected with the collar, and the lower end is connected with the plunger; the water pipe passes through the upper joint and the The lower joint is connected, and there are screen holes of different diameters on the pipe wall of the tail pipe. The upper end is connected with the pump barrel and the water pipe column, and the lower end is anchored together with the bottom end cover and the body through the pin shaft; the casing is connected by a thread , the port of the bottom hole tee is connected with the air inlet pipe, its upper end is connected with the casing string through bolts, its lower end is connected with the sealing bottom plate of the sealing box and the sealing body, the lower end of the sealing body is connected with the bottom plate through stud bolts, and the bottom plate is passed through channel The frame of the welded structure is fixed on the end face of the well bottom; the floating valve assembly is located at the upper end of the plunger, the upper part of which is connected with the variable diameter short rod, and the lower part is connected with the plunger, and the fixed valve assembly is fixed on the pump barrel through a locking device The lower end of the; the electromagnetic flowmeter is installed on the water inlet pipe of the water storage device, and the pressure transmitter is installed on the four-way port of the wellhead device and the bottom of the well At the tee port, the liquid level transmitter is installed at the bottom of the well below the dynamic liquid level in the annulus of the water jacket, and the strain gauges of the wireless dynamic stress gauge are attached to the upper ends of the rods of the pump and the upper end of the drainage rod, and the test rod piece of force. 2. The drainage and gas recovery simulation experiment device according to claim 1, characterized in that: the packing of the sealing box of the wellhead device can be a new or old ordinary V-belt, and the sealing packing of the sealing box at the bottom of the casing string can be a rectangular sealing ring. the 3. The drainage and gas collection simulation experiment device according to claim 1, characterized in that: the data collector and the instrument with single input channel are connected to the testing equipment at one end and to the computer at the other end through a serial port. 4. The drainage and gas recovery simulation experiment device according to claim 1, characterized in that: the support of the water pump is fixed on the base in the form of four legs with two legs at the front and two legs at the rear. 5. The drainage and gas recovery simulation experiment device according to claim 1, characterized in that: the support of the water pump is fixed on the base in the form of three legs with a single front leg and two rear legs. the

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