CN206386111U - A kind of experimental provision for testing cement sheath and sleeve pipe cementing strength - Google Patents

Abstract

The utility model provides an experimental device for testing the bonding strength of the cement sheath and the casing, which includes: a kettle body, a plurality of casing pipes inside the kettle body, including: a simulated stratum, and a confining pressure chamber formed between the shell of the holder; The casing inside the simulated formation is coaxially sleeved with the simulated formation, and forms a cement annulus with the simulated formation; it also includes: a cement slurry storage tank; a heating rod, which is lowered into the inner cavity of the casing; Confining pressure pump; confining pressure sensor located between confining pressure chamber and automatic confining pressure pump; high pressure pump; high pressure pump pressure sensor located between high pressure pump and piston; pressure bearing block located between piston and sleeve; sleeve A temperature sensor is inserted in the inner cavity of the pipe and the annulus of the cement annulus; an internal pressure sensor is inserted in the inner cavity of the casing; and a pressure sensor is inserted in the annulus of the cement annulus. By implementing the utility model, the bonding strength between the cement sheath and the casing pipe can be simulated under the temperature and pressure conditions of different working conditions.

Description

An experimental device for testing the bonding strength of cement sheath and casing

technical field

The utility model relates to the field of oil and gas well engineering, in particular to an experimental device for testing the bonding strength of a cement sheath and a casing.

Background technique

In order to improve oil and gas recovery and production, a series of production stimulation measures such as perforation, acidification, fracturing, and high-pressure water injection have put forward high requirements on the quality of cementing. Especially in high temperature and high pressure wells and thermal recovery wells, the downhole temperature is high, which is a severe challenge to the cementing quality. If the cementing quality is not good, complex underground geological conditions will have a great impact on oil and gas production, mainly including oil, gas and water leakage outside the pipe, well wall collapse, channeling and even well scrapping. There are many factors affecting the bonding strength between the cement sheath and the casing, such as casing roughness, waiting setting time, temperature, cement components, and cement height. Studying the influence law of cement sheath and casing bonding strength and improving cementing quality can provide guarantee for the development of difficult-to-recover oil and gas such as heavy oil.

Therefore, it is of great significance to study the influence law of cement sheath and casing bond strength. However, the current experimental device cannot fully simulate the bond strength between the cement sheath and the casing under different working conditions of temperature and pressure, and cannot provide experimental data for cementing quality evaluation.

Utility model content

The main purpose of the embodiment of the utility model is to provide an experimental device for testing the bonding strength of the cement sheath and casing, which is used to simulate the bonding strength of the cement sheath and casing under different temperature and pressure conditions. In order to achieve the above purpose, the embodiment of the utility model provides an experimental device for testing the bonding strength of the cement sheath and the casing, including: a kettle body, a plurality of casing pipes inside the kettle body, including: a simulated formation, and a joint between the casing of the holder A confining pressure chamber is formed between them; the casing located inside the simulated formation and coaxial with the simulated formation forms a cement sheath annulus with the simulated formation; the experimental device for testing the bonding strength of the cement sheath and the casing also includes: a cement slurry storage tank , used to inject cement slurry into the annulus of the cement annulus; the heating rod is lowered into the inner cavity of the casing to heat the heating fluid to the set temperature; the automatic confining pressure pump connected to the confining pressure chamber is used to apply the device to the simulated formation Constant confining pressure; the confining pressure sensor located between the confining pressure chamber and the automatic confining pressure pump is used to collect confining pressure data; the high pressure pump is used to apply pressure to the piston; the high pressure pump pressure sensor located between the high pressure pump and the piston , used to collect high-pressure pump pressure data; the pressure block located between the piston and the casing is used to apply axial force to the casing; temperature sensors are inserted in the inner cavity of the casing and the cement ring annulus to collect temperature data ; An internal pressure sensor is inserted in the inner cavity of the casing for collecting internal pressure data; a pressure sensor is inserted in the cement annulus for collecting pressure data.

In one of the embodiments, it also includes: a control device connected to the heating rod, the automatic confining pressure pump, the high pressure pump, the confining pressure sensor, the high pressure pump pressure sensor, a plurality of temperature sensors, the internal pressure sensor, and the pressure sensor respectively, It is used to control the heating rod to heat the heating fluid, control the automatic confining pressure pump to apply the set confining pressure to the simulated formation, control the high pressure pump to apply pressure to the piston, collect the confining pressure data from the confining pressure sensor, and the high pressure pump pressure from the high pressure pump pressure sensor data, a plurality of temperature data from a plurality of temperature sensors, internal pressure data from an internal pressure sensor, and pressure data from a pressure sensor.

In one of the embodiments, it also includes: a high-pressure pump control valve, the first end of which is connected to the high-pressure pump, and the second end is connected to the piston; the automatic confining pressure pump control valve, the first end of which is connected to the automatic confining pressure pump, and the second The end is connected to the confining pressure chamber.

In one of the embodiments, it also includes: a kettle body, including an upper kettle cover and a lower kettle base; each of the upper kettle cover and the lower kettle base has a plurality of grooves opposite to each other for inserting the simulated formation and the casing respectively.

In one of the embodiments, it further includes: a plurality of sealing rings, used for sealing the plurality of grooves.

In one of the embodiments, the upper kettle cover has a buffer rubber ring above the casing to prevent the casing from impacting and damaging the upper kettle cover.

In one of the embodiments, it also includes: an upper flow channel located on the upper kettle cover; the upper flow channel is connected to a condensate pump, and the condensate pump is used to transport condensed water to cool the upper kettle cover; the condensate pump control valve, the first end of which is connected to the upper flow channel , the second end is connected to the condensate pump.

Because the experimental device for testing the bonding strength of the cement sheath and the casing of the present invention injects cement slurry into the cement annulus annulus through the cement slurry storage tank to simulate the geological environment of the formation, heats the heating liquid to the set temperature through the heating rod, and uses the high-pressure pump to control the piston. Apply pressure, apply axial force to the casing through the piston and pressure bearing block, apply the set confining pressure to the simulated formation through the automatic confining pressure pump, and use the confining pressure sensor, high pressure pump pressure sensor, temperature sensor, internal pressure sensor and pressure sensor Data collection is carried out to simulate the bond strength between the cement sheath and the casing under different temperature and pressure conditions.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description are only the present invention For some novel embodiments, those of ordinary skill in the art can also obtain other drawings based on these drawings without any creative work.

Fig. 1 is a structural block diagram of an experimental device for testing the bonding strength between a cement sheath and a casing in an embodiment of the utility model.

detailed description

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. example. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

In view of the fact that the prior art cannot fully simulate the bond strength between the cement sheath and the casing under different temperature and pressure conditions, the embodiment of the utility model provides an experimental device for testing the bond strength between the cement sheath and the casing. Cement slurry is injected into the cement annulus to simulate the geological environment of the formation, the heating fluid is heated to the set temperature through the heating rod, the pressure is applied to the piston through the high-pressure pump, the axial force is applied to the casing through the piston and the pressure block, and the automatic confining pressure pump Apply the set confining pressure to the simulated formation, and collect data through the confining pressure sensor, high pressure pump pressure sensor, temperature sensor, internal pressure sensor and pressure sensor, so as to simulate the cement sheath and casing bonding strength under different temperature and pressure conditions . The utility model is described in detail below in conjunction with accompanying drawing.

Fig. 1 is a structural block diagram of an experimental device for testing the bonding strength between a cement sheath and a casing in an embodiment of the utility model. As shown in Figure 1, the experimental device for testing the bonding strength between the cement sheath and the casing includes: a kettle body with multiple casings inside the kettle body, including a simulated formation 8, and a confining pressure chamber 25 formed between the holder shell 7 The casing 22 located inside the simulated formation 8 and coaxial with the simulated formation 8 forms a cement annulus 24 with the simulated formation 8; the experimental device for testing the bonding strength of the cement sheath and the casing also includes: a cement slurry storage tank 21 is used to inject cement slurry into the cement annulus 24; the heating rod 15 is lowered into the casing inner cavity 23 to heat the heating fluid to the set temperature; the automatic confining pressure pump 5 connected to the confining pressure chamber 25 is used to To apply the set confining pressure to the simulated formation 8; the confining pressure sensor 6 between the confining pressure chamber 25 and the automatic confining pressure pump 5 is used to collect confining pressure data; the high pressure pump 2 is used to apply pressure to the piston 28; The high-pressure pump pressure sensor 3 between the high-pressure pump 2 and the piston 28 is used to collect the pressure data of the high-pressure pump; the pressure block 27 located between the piston 28 and the sleeve 22 is used to apply an axial force to the sleeve 22; Both the casing inner cavity 23 and the cement ring annulus 24 are inserted with a temperature sensor 13 for collecting temperature data; the casing inner cavity 23 is inserted with an internal pressure sensor 16 for collecting internal pressure data; the cement annulus annulus 24 is inserted with a pressure sensor 17, used to collect pressure data.

During specific implementation, the still body can include an upper kettle cover 10 and a lower kettle seat 29, and a sealed shell cover is provided on the top of the upper kettle cover 10 for heat insulation. Both the upper kettle cover 10 and the lower kettle base 29 have multiple grooves opposite to each other for inserting the simulated formation 8 and the casing 22 respectively, wherein the grooves can be multiple concentric circles of different sizes. The experimental device for testing the bonding strength between the cement sheath and the casing may also include multiple sealing rings for sealing multiple grooves.

In the embodiment, the cement slurry storage tank 21, the high-pressure pump 2 and the automatic confining pressure pump 5 can all be connected to the kettle body through an input manifold. The cement slurry storage tank 21 injects a certain volume of cement slurry into the cement annulus 24 through the injection port 18 to simulate the formation geological environment. Wherein, the ratio of the components of the cement slurry can be adjusted arbitrarily according to the needs of the experiment. The heating rod 15 can heat the heating liquid to a set temperature by means of electric heating, so that the heat can be transferred outward, simulating the temperature environment of the high-temperature fluid and the well. Wherein, the heating fluid can be oil or water. The automatic confining pressure pump 5 applies a set confining pressure to the simulated formation 8 to simulate the confining pressure of the formation, and the high-pressure pump 2 applies pressure to the piston 28 inside the lower kettle seat 29 through the internal pressure port 30, and loads the pressure on the pressure block 27 to seal the casing. 22 Apply an axial force to simulate the axial load of the casing. Confining pressure sensor 6, high pressure pump pressure sensor 3, multiple temperature sensors 13, internal pressure sensor 16 and pressure sensor 17 collect data, and simulate the cement sheath and casing bonding strength under different temperature and pressure conditions according to the data changes.

As shown in Figure 1, the experimental device for testing the bonding strength between the cement sheath and the casing can also include: respectively with the heating rod 15, the automatic confining pressure pump 5, the high pressure pump 2, the confining pressure sensor 6, the high pressure pump pressure sensor 3, a plurality of The temperature sensor 13, the internal pressure sensor 16, and the control device 4 connected to the pressure sensor 17 are used to control the heating rod 15 to heat the heating fluid, control the automatic confining pressure pump 5 to apply a set confining pressure to the simulated formation 8, and control the high pressure pump 2 to Piston 28 exerts pressure to collect confining pressure data from confining pressure sensor 6, high pressure pump pressure data from high pressure pump pressure sensor 3, multiple temperature data from multiple temperature sensors 13, internal pressure data from internal pressure sensor 16, and pressure data from the pressure sensor 17. The heating rod 15, the automatic confining pressure pump 5, the high pressure pump 2, the confining pressure sensor 6, the high pressure pump pressure sensor 3, multiple temperature sensors 13, the internal pressure sensor 16, and the pressure sensor 17 can be connected with the control device 4 through the data acquisition line , can also be connected with the control device 4 through wireless communication devices such as bluetooth and GPRS.

In the embodiment, the experimental device for testing the bonding strength between the cement sheath and the casing may also include: a high-pressure pump control valve 1, the first end of which is connected to the high-pressure pump 2, and the second end is connected to the piston 28; an automatic confining pressure pump control valve 31, The first end is connected with the automatic confining pressure pump 5 , and the second end is connected with the confining pressure chamber 25 . During specific implementation, the opening and closing of the high-pressure pump control valve 1 can also be controlled by the control device 4 to control the high-pressure pump 2 to apply pressure to the piston 28; the opening and closing of the automatic confining pressure pump control valve 31 can be controlled to control the automatic confining pressure. The pressure pump 5 applies a set confining pressure to the simulated formation 8 .

In the embodiment, the experimental device for testing the bonding strength between the cement sheath and the casing may further include: the upper kettle cover 10 has a buffer rubber ring 12 above the casing 22 to prevent the casing 22 from impacting and damaging the upper kettle cover 10 .

As shown in Figure 1, the experimental device for testing the bonding strength of the cement sheath and the casing can also include: an upper flow channel positioned at the upper kettle cover 10; the upper flow channel is connected with a condensate pump 20, and the condensate pump 20 is used to transport condensed water to cool the upper kettle cover 10; the condensate pump control valve 19, the first end is connected to the upper flow channel, and the second end is connected to the condensate pump 20. By cooling the condensate pump 20 of the still body, it is possible to prevent the failure of the O-ring due to excessive temperature of the still body.

Concrete work process of the present utility model is:

1. Inject heating fluid into the casing inner cavity 23, and inject cement slurry into the cement annulus 24 from the cement slurry storage tank 21;

2. The heating rod 15 heats the heating liquid to the set temperature;

3. The automatic confining pressure pump 5 applies a set confining pressure to the simulated formation 8;

4. Set the time for maintaining the experimental device for testing the bonding strength of the cement sheath and the casing until the cement sheath, the simulated formation 8 and the casing 22 are cemented into a whole;

5. Turn off the heating rod 15 to lower the temperature of the heating liquid to normal temperature, turn off the automatic confining pressure pump 5, remove the heating rod 15, and pour out the heating liquid;

6. The high-pressure pump 2 applies pressure to the piston 28 until the pressure data of the high-pressure pump continues to drop. During this process, record the confining pressure data from the confining pressure sensor 6, the high-pressure pump pressure data from the high-pressure pump pressure sensor 3, and the A plurality of temperature data from the temperature sensor 13 , internal pressure data from the internal pressure sensor 16 , and pressure data from the pressure sensor 17 .

During specific implementation, the groove can be sealed with an O-shaped sealing rubber ring, and the simulated formation 8 and the casing 22 are inserted into the corresponding groove of the lower kettle base 29 to be assembled with the upper kettle cover 10 . A heating liquid is injected into the inner cavity 23 of the casing, and the heating liquid may be water or oil.

In an embodiment, the heating rod 15 can be lowered from the center of the upper kettle cover 10 to be fixed and sealed. Cement slurry is configured in the slurry storage tank 21 according to a certain ratio. Wherein, the ratio of the components of the cement slurry can be adjusted arbitrarily according to the needs of the experiment. The effect of different types of cement slurry on fluid pressure in annular traps can be tested by changing the type of cement slurry. The cement slurry with a set proportion is injected into the cement annulus 24 through the cement slurry storage tank 21 , and the cement slurry with different proportions in the cement annulus 24 will have different cement slurry return heights. By changing the volume of the cement slurry in the cement annulus annulus 24, the result of the influence of the cement annulus height on the fluid pressure of the second annulus trap can be obtained.

During specific implementation, the temperature data of the temperature sensor 13 heated by the heating rod 15 to the casing 22 can be 120°C to simulate the formation temperature; the automatic confining pressure pump 5 can apply a confining pressure of 60Mpa to the simulated formation 8; the maintenance can be changed The time of the experimental device for testing the bonding strength of the cement sheath and the casing to simulate the influence of the curing time of the cement sheath on the bonding strength of the cement sheath and the casing.

In practice, after the cement sheath, the simulated formation 8 and the casing 22 are cemented together, the heating rod 15 is turned off to lower the temperature of the heating fluid to normal temperature, and then heated to the set temperature again to simulate steam stimulation. Working process 5 and working process 6 can be performed after the cooling and heating cycle can be alternated multiple times to simulate the influence of steam huff and puff on the bond strength between the cement sheath and the casing.

In the embodiment, the sleeves include smooth sleeves, threaded sleeves, concave-convex sleeves and frosted sleeves. By changing different types of casings, the effect of different casing roughness on the bond strength between cement sheath and casing can be tested.

The main technical indicators of the utility model are as follows:

1) Experimental temperature: room temperature -220°C;

2) Internal pressure: 0-15Mpa;

3) Confining pressure: 0-60Mpa;

4) Casing size: Casing size: inner diameter 60mm outer diameter 75mm length 200mm;

5) Simulated formation size: inner diameter 105mm outer diameter 115mm length 200mm;

6) Thickness of cement sheath: 15mm;

7) High pressure pump pressure range: 100KN-200KN;

8) Pressure sensor: the measuring range of confining pressure sensor, high pressure pump pressure sensor and pressure sensor is 70MPa, the measuring range of internal pressure sensor is 20MPa; the sensor sensitivity is 0.27% FS.

Wherein, the normal temperature may be 25°C.

In summary, the experimental device for testing the bonding strength between the cement annulus and the casing of the present invention injects cement slurry into the cement annulus annulus through the cement slurry storage tank to simulate the geological environment of the formation, heats the heating liquid to the set temperature through the heating rod, and passes through the high-pressure pump Apply pressure to the piston, apply axial force to the casing through the piston and the pressure bearing block, apply the set confining pressure to the simulated formation through the automatic confining pressure pump, and use the confining pressure sensor, high pressure pump pressure sensor, temperature sensor, internal pressure sensor and The pressure sensor collects data to simulate the bonding strength between the cement sheath and the casing under different temperature and pressure conditions. The embodiment of the utility model can also cool the kettle body through the condensate pump, so as to prevent the failure of the O-shaped sealing ring caused by the excessive temperature of the kettle.

The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present utility model in detail. Within the protection scope of the utility model, any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the utility model shall be included in the protection scope of the utility model.

Claims (7)

1. a kind of experimental provision for testing cement sheath and sleeve pipe cementing strength, it is characterised in that including：

There are multiple sleeve pipes inside kettle, kettle, including：

Confined pressure chamber (25) is constituted between simulated formation (8), with clamper shell (7)；

The sleeve pipe (22) being coaxially nested positioned at simulated formation (8) inside, with simulated formation (8), and form water with simulated formation (8) Mud ring annular space (24)；

The experimental provision of test cement sheath and sleeve pipe cementing strength also includes：

Cement mortar holding vessel (21), for injecting cement mortar to cement sheath annular space (24)；

Heating rod (15), is lowered into cannula cavity (23), for heating liquid to design temperature；

The automatic confined pressure pump (5) being connected with confined pressure chamber (25), for applying setting confined pressure to simulated formation (8)；

Confined pressure sensor (6) between confined pressure chamber (25) and automatic confined pressure pump (5), for gathering confined pressure data；

High-pressure pump (2), for applying pressure to piston (28)；

High pressure pump pressure sensor (3) between high-pressure pump (2) and piston (28), for gathering high-pressure pump number pressure According to；

Pressure block (27) between piston (28) and sleeve pipe (22), for applying axial force to sleeve pipe (22)；

Cannula cavity (23) and cement sheath annular space (24) are inserted with temperature sensor (13), for collecting temperature data；

Cannula cavity (23) is inserted with interior pressure sensor (16), for gathering internal pressure data；

Cement sheath annular space (24) is inserted with pressure sensor (17), for gathering pressure data.

2. the experimental provision of test cement sheath according to claim 1 and sleeve pipe cementing strength, it is characterised in that also wrap Include：

Respectively with heating rod (15), automatic confined pressure pump (5), high-pressure pump (2), confined pressure sensor (6), high pressure pump pressure sensor (3), the control device (4) of multiple temperature sensors (13), interior pressure sensor (16) and pressure sensor (17) connection, is used In control heating rod (15) heating heating liquid, automatic confined pressure pump (5) is controlled to apply setting confined pressure to simulated formation (8), control is high Press pump (2) applies pressure to piston (28), and collection comes from the confined pressure data of confined pressure sensor (6), from high-pressure pump pressure sensing The high-pressure pump pressure data of device (3), multiple temperature datas from multiple temperature sensors (13), from interior pressure sensor (16) Internal pressure data and pressure data from pressure sensor (17).

3. the experimental provision of test cement sheath according to claim 1 and sleeve pipe cementing strength, it is characterised in that also wrap Include：

High pressure pump control valve (1), first end is connected with high-pressure pump (2), and the second end is connected with piston (28)；

Automatic confined pressure pump control valve (31), first end is connected with automatic confined pressure pump (5), and the second end is connected with confined pressure chamber (25).

4. the experimental provision of test cement sheath according to claim 1 and sleeve pipe cementing strength, it is characterised in that also wrap Include：

Kettle, including upper kettle cover (10) and lower kettle seat (29)；

Have multiple grooves facing each other on upper kettle cover (10) and lower kettle seat (29), for insert respectively simulated formation (8) and Sleeve pipe (22).

5. the experimental provision of test cement sheath according to claim 4 and sleeve pipe cementing strength, it is characterised in that also wrap Include：

Multiple sealing rings, for sealing multiple grooves.

6. the experimental provision of test cement sheath according to claim 4 and sleeve pipe cementing strength, it is characterised in that

Upper kettle cover (10) is equipped with buffering apron (12) in the upper position of sleeve pipe (22), for preventing kettle in sleeve pipe (22) impact failure Cover (10).

7. the experimental provision of test cement sheath according to claim 4 and sleeve pipe cementing strength, it is characterised in that also wrap Include：

Upper runner positioned at upper kettle cover (10)；

Upper runner is connected with condenser pump (20), and condenser pump (20) is used to convey kettle cover (10) in condensation water cooling；

Pump control valve (19) is condensed, first end is connected with upper runner, and the second end is connected with condenser pump (20).