CN216894375U

CN216894375U - Low-pollution sampling device for formation fluid while drilling

Info

Publication number: CN216894375U
Application number: CN202122661435.9U
Authority: CN
Inventors: 孙浩玉; 陈忠帅; 刘业文; 张辉; 张俊杰; 吴仲华; 刘志和; 陈勇; 陈锐; 刘晗; 王贵亭; 马雪刚; 李浩博
Original assignee: Sinopec Oilfield Service Corp; Sinopec Shengli Petroleum Engineering Corp; Drilling Technology Research Institute of Sinopec Shengli Petroleum Engineering Corp
Current assignee: China Petrochemical Corp; Sinopec Oilfield Service Corp; Sinopec Shengli Petroleum Engineering Corp; Drilling Technology Research Institute of Sinopec Shengli Petroleum Engineering Corp
Priority date: 2021-11-02
Filing date: 2021-11-02
Publication date: 2022-07-05
Anticipated expiration: 2031-11-02

Abstract

The utility model relates to the technical field of petroleum and natural gas drilling formation fluid sampling, in particular to a low-pollution sampling device for formation fluid while drilling, which consists of an outer shell, a suction power assembly and a pre-flushing mechanism assembly, wherein the suction power assembly and the pre-flushing mechanism assembly are fixed on the outer shell through clamp springs, and a suction power assembly consists of a battery, a motor, a speed reducer, a ball screw, a piston and a sampling cylinder and can suck and store the formation fluid into the sampling cylinder. The balance piston, the sampling cylinder, the draft tube and the 3 check valves form a pre-flushing mechanism assembly, a buffer solution is filled in a cavity between the balance piston and the sampling cylinder, the impact of high-pressure stratum fluid can be buffered, and the pre-flushing mechanism assembly can enable a target layer fluid without interference components to be filled in the cavity between the sampling cylinder and the balance piston by controlling the switch of the check valve before sampling operation is started.

Description

Low-pollution sampling device for formation fluid while drilling

Technical Field

The utility model relates to the technical field of petroleum and natural gas drilling formation fluid sampling, in particular to a low-pollution sampling device for formation fluid while drilling, which is used for extracting and storing original formation fluid.

Background

The properties of chemical components, viscosity, gas phase envelope, solid phase envelope and the like of the stratum reservoir have great influence on the evaluation of the physical properties of the reservoir. The method has the advantages that the method obtains the geological parameters such as the type and the property of the fluid by collecting representative stratum fluid samples, has very important significance for accurately determining the oil-gas containing condition of a reservoir and reasonably making a long-term development scheme in an oil-gas field, and is extremely important for accurately measuring the property of the reservoir fluid based on the reasons.

There are a variety of methods available today for obtaining wellbore fluid samples. The method for acquiring the formation fluid while drilling can accurately reflect the properties of the wellbore fluid during real drilling, and the original formation fluid is acquired on the well wall through negative pressure suction by using a while-drilling tool. However, since the tool may enter the tool sampling cavity before being lowered into the well casing and operation is started, formation fluid in a target stratum is polluted and mixed with other components, so that data measured in a laboratory is distorted, a large error is generated, and negative influence is caused on productivity evaluation.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a low-pollution sampling device for formation fluid while drilling, aiming at the defects in the prior art.

Formation fluid can be pumped and stored into the device, and a pre-flushing action can be carried out before pumping operation, so that the pumped and stored fluid only contains the target formation fluid and no other interference components.

The technical scheme is as follows:

a low-pollution sampling device for formation fluid while drilling comprises an outer shell, a sampling cylinder, a suction power assembly and a pre-flushing mechanism assembly;

the outer shell is tubular, and the sampling cylinder is fixedly arranged at the middle section of the outer shell;

the pumping power assembly comprises a driving component, a ball screw and a piston cylinder, the driving component is fixedly arranged at the rear section of the outer shell, the driving component is in driving connection with the ball screw, the ball screw is in spiral transmission connection with the piston cylinder, the piston cylinder is arranged at the middle rear section of the sampling cylinder, and the piston cylinder is in sliding sealing fit with the sampling cylinder;

the pre-flushing mechanism assembly comprises a balance piston, a flow guide pipe, a first one-way valve, a second one-way valve and a third one-way valve; the balance piston is arranged at the front section of the sampling cylinder and is in sliding sealing fit with the sampling cylinder; the number of the flow guide pipes is three, one flow guide pipe is communicated between the piston cylinder and the balance piston and is provided with a first one-way valve, and the other two flow guide pipes are communicated with the front end of the sampling cylinder and are respectively provided with a second one-way valve and a third one-way valve; the first one-way valve and the second one-way valve are communicated from inside to outside, and the third one-way valve is communicated from outside to inside.

Furthermore, the driving assembly comprises a power supply bin, a battery, a motor and a speed reducer, the power supply bin is fixedly arranged on the outer shell, the battery is arranged in the power supply bin and electrically connected with the motor, the driving end of the motor is connected with the speed reducer, and the speed reducer is connected with the ball screw.

Furthermore, a bin cover is fixedly arranged at the rear end of the power supply bin, and the bin cover, the battery bin and the motor are sequentially compressed to form a sealed cavity.

Furthermore, a sealing ring is arranged between the outer wall of the power supply bin and the inner wall of the outer shell.

Further, be equipped with the sealing washer between piston barrel outer wall and the sampling tube inner wall, between balanced piston outer wall and the sampling tube inner wall.

Furthermore, the rear end of the sampling tube is provided with an extended limiting step, and the sampling tube is fixed and positioned through the step inside the outer shell.

Furthermore, the rear end of the motor is connected with a wire plug at the front end of the power supply bin, and the front end of the motor is connected with the speed reducer through threads.

Further, the balance piston is separated from the front end of the piston cylinder by a distance.

Furthermore, the first one-way valve, the second one-way valve and the third one-way valve are switched on and off through ground remote control.

Further, the motor is directly powered by a battery and is remotely controlled by the ground.

Furthermore, the inner cavity of the piston cylinder is connected with a ball screw through threads, and the ball screw drives the piston cylinder to do linear reciprocating motion through the threads when rotating forwards or reversely.

Furthermore, a cavity between the piston cylinder and the balance piston in the sampling cylinder is filled with a buffer solution, certain hydraulic pressure is kept, and the cavity between the balance piston and the lower end of the sampling cylinder is not filled with liquid.

The utility model has the beneficial effects that:

by applying the while-drilling formation fluid low-pollution sampling technology and the suction power device provided by the utility model, the sampling cavity can be pre-flushed before suction operation, so that the true reliability of formation fluid property parameter evaluation is improved. The method ensures the reliability of the piston action by controlling the rotation of the ball screw through the direct current motor, and the direct current motor can rotate positively and negatively, the piston extracts formation fluid in positive rotation and discharges the formation fluid in negative rotation, and can operate for many times under the condition of sufficient buffer solution, thereby improving the economical efficiency.

Drawings

FIG. 1 is a schematic diagram of the present invention.

FIG. 2 is a schematic view of the utility model assembled and ready for downhole use.

FIG. 3 is a schematic view of the pre-flush state of the present invention.

FIG. 4 is a schematic view of the pumping operation of the present invention

FIG. 5 is a schematic view of the state of the sampled fluid being discharged according to the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings in conjunction with the following detailed description. It should be understood that the description is intended to be exemplary only, and is not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

Referring to fig. 1, the present invention is composed of an outer casing 1, a suction power assembly and a pre-flush mechanism assembly.

The suction power assembly comprises a clamp spring 2, a sealing ring 3, a battery cabin cover 20, a sealing ring 21, a battery cabin 4, a battery 5, a direct current motor 6, a speed reducer 7, a bearing 8, a bearing supporting plate 9, a ball screw 11, a piston 12 and a sealing ring 13.

The pre-flushing mechanism assembly consists of a sampling cylinder 10, a balance piston 14, a sealing ring 15, a guide pipe 16, a No. 1 one-way valve 17, a No. 2 one-way valve 18 and a No. 3 one-way valve 19.

The outer shell 1 completely contains a clamp spring 2, a sealing ring 3, a battery cabin cover 20, a sealing ring 21, a battery cabin 4, a battery 5, a direct current motor 6, a speed reducer 7, a bearing 8, a bearing supporting plate 9, a ball screw 11, a piston 12, a sealing ring 13, a sampling cylinder 10, a balance piston 14, a sealing ring 15, a flow guide pipe 16, a check valve 1 17, a check valve 2 18 and a check valve 3 19.

The battery compartment 4, the direct current motor 6, the speed reducer 7 and the ball screw 11 are connected in sequence, and the ball screw 11 is connected with the piston 12 through threads. A piston 12 is mounted inside the sampling cylinder 10, and a sealing ring 13 is provided on the piston 12 to ensure the sealing of the sampling cylinder 10. The sampling tube 10 is mounted inside the outer housing 1, fixed and positioned by a step inside the outer housing 1. The battery 5 is mounted in the battery compartment 4 with a hard wire plug at the front end and a battery compartment cover 20 at the rear end. The battery compartment cover 20 is connected with the battery compartment 4 through threads, a sealing ring 21 is arranged on the battery compartment cover 20, and the battery compartment 4 is sealed through the sealing ring 21. The rear end of the direct current motor 6 is connected with an electric wire plug at the front end of the battery compartment 4, and the front end of the direct current motor 6 is connected with the speed reducer 7 through threads. The rear end of the speed reducer 7 is connected with the ball screw 11 through threads, and the rear end of the speed reducer 7 is tightly pressed with the upper end face of the bearing 8. The lower end surface of the bearing 8 presses the bearing supporting plate 9 tightly, and the lower end surface of the bearing supporting plate 9 tightly presses the upper end surface of the sampling tube 10. The clamp spring 2 compresses the battery compartment 4, so that the sealing ring 3, the battery compartment cover 20, the sealing ring 21, the battery compartment 4, the battery 5, the direct current motor 6, the speed reducer 7, the bearing 8, the bearing supporting plate 9, the ball screw 11, the piston 12, the sealing ring 13 and the sampling cylinder 10 are all fixed.

A balance piston 14 is mounted inside the sampling cylinder 10 at a distance from the piston 12, the balance piston 14 having a seal 13 circumferentially disposed thereon. The rear end of the sampling tube 10 is connected with 3 draft tubes 16. 3 one-way valves, namely a No. 1 one-way valve 17, a No. 2 one-way valve 18 and a No. 3 one-way valve 19 are connected to the 3 draft tubes 16. One end of a draft tube 16 at the top is communicated with the middle lower part of the sampling tube 10, and the other end is communicated with a No. 1 one-way valve 17 and then communicated with the outside. The other two draft tubes 16 are communicated with the rear end of the sampling tube 10 at one end, and communicated with the outside after being respectively connected with a No. 2 one-way valve 18 and a No. 3 one-way valve 19 at one end. The conducting direction of the check valve No. 1 17 is from left to right, the conducting direction of the check valve No. 2 18 is from left to right, and the conducting direction of the check valve No. 3 19 is from right to left.

The No. 1 check valve 17, the No. 2 check valve 18 and the No. 3 check valve 19 can be switched on and off by the ground remote control. The direct current motor 6 is directly powered by the battery 5 and can be remotely controlled by the ground. The battery compartment 4 is sealed by a gasket 3 to ensure the sealing of the dc motor 6 and the speed reducer 7. The ball screw 11 is sleeved with a bearing 8 to ensure that friction when the ball screw 11 rotates is sufficiently small. The inner cavity of the piston 12 is connected with the ball screw 11 through threads, and when the ball screw 11 rotates forwards or backwards, the piston 12 is lifted or lowered relative to the sampling cylinder 10 through the threads. The sampling tube 10 has a step inside, and the piston 12 stops moving to the step.

Referring to fig. 2, after the complete device is assembled, the cavity between the piston 12 and the balance piston 14 inside the sampling tube 10 is filled with buffer solution, a certain hydraulic pressure is maintained, the cavity between the balance piston 14 and the lower end of the sampling tube 10 is not filled with liquid, and the check valve 1, the check valve 2, the check valve 18 and the check valve 3 19 are all closed.

As shown in fig. 3, after the whole device is assembled, the device is put into the well bottom, and when the device does not reach the sampling destination layer, the

check valves

17, 18 and 19 No. 1, 2 and 3 are all closed. When the sampling target layer is reached, the

check valves

18 and 19 No. 2 and 3 are opened under the control of the ground, the formation fluid enters the cavity between the balance piston 14 and the lower end of the sampling tube 10, and the buffer solution is filled in the cavity between the piston 12 and the balance piston 14, so that the balance piston 14 is not impacted by the violent pushing action of the high-pressure formation fluid on the balance piston 14. The formation fluid washes the cavity clean to ensure that only the sampling target layer fluid exists in the cavity, and at the moment, the pressures at the left end and the right end of the balance piston 14 reach a balance state.

As shown in figure 4, when the whole set of device starts pumping operation, the No. 1 check valve 17 and the No. 3 check valve 19 are all opened under the control of the ground, and the No. 2 check valve 18 is closed. Under the control of the ground, the direct current motor 6 starts to rotate to drive the ball screw to rotate, the piston 12 starts to be lifted through threads on the ball screw, the volume of a cavity between the piston 12 and the balance piston 14 is increased, under the action of external pressure, formation fluid enters the cavity between the balance piston 14 and the lower end of the sampling cylinder 10 through a flow guide pipe with a No. 3 one-way valve 19, and meanwhile, buffer solution in the cavity between the piston 12 and the balance piston 14 is discharged through the flow guide pipe connected with a No. 1 one-way valve 17. After the fluid is determined to meet the requirement, under the ground control, the direct current motor 6 stops rotating, the

check valves

17 and 18 and 19 are closed, and the fluid pumping operation is finished.

As shown in fig. 5, during or after the pumping operation of the whole device, if the obtained formation fluid is deemed not to meet the requirement, the direct current motor 6 can be controlled from the surface to rotate reversely, the check valve No. 1 17 is closed, and the check valve No. 2 is opened. The direct current motor 6 reversely rotates to push the piston 12 down, the balance piston 14 is extruded, and fluid in a cavity between the balance piston 14 and the lower end of the sampling tube 10 is discharged, so that subsequent construction operation is facilitated.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the utility model, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A low-pollution sampling device for formation fluid while drilling is characterized by comprising an outer shell, a sampling cylinder, a suction power assembly and a pre-flushing mechanism assembly; the outer shell is tubular, and the sampling cylinder is fixedly arranged at the middle section of the outer shell; the pumping power assembly comprises a driving component, a ball screw and a piston cylinder, the driving component is fixedly arranged at the rear section of the outer shell, the driving component is in driving connection with the ball screw, the ball screw is in spiral transmission connection with the piston cylinder, the piston cylinder is arranged at the middle rear section of the sampling cylinder, and the piston cylinder is in sliding sealing fit with the sampling cylinder; the pre-flushing mechanism assembly comprises a balance piston, a flow guide pipe, a first one-way valve, a second one-way valve and a third one-way valve; the balance piston is arranged at the front section of the sampling cylinder and is in sliding sealing fit with the sampling cylinder; the number of the flow guide pipes is three, one flow guide pipe is communicated between the piston cylinder and the balance piston and is provided with a first one-way valve, and the other two flow guide pipes are communicated with the front end of the sampling cylinder and are respectively provided with a second one-way valve and a third one-way valve; the first one-way valve and the second one-way valve are communicated from inside to outside, and the third one-way valve is communicated from outside to inside.

2. The device for sampling while drilling formation fluid with low pollution as recited in claim 1, wherein the driving assembly comprises a power supply bin, a battery, a motor and a speed reducer, the power supply bin is fixedly arranged on the outer shell, the battery is arranged in the power supply bin, the battery is electrically connected with the motor, a driving end of the motor is connected with the speed reducer, and the speed reducer is connected with the ball screw.

3. The device for sampling while drilling formation fluid with low pollution as recited in claim 2, wherein a bin cover is fixedly arranged at the rear end of the power supply bin, and the bin cover, the battery bin and the motor are sequentially compressed to form a sealed cavity.

4. The device for sampling while drilling formation fluid with low pollution as recited in claim 3, wherein a sealing ring is arranged between the outer wall of the power supply bin and the inner wall of the outer shell.

5. The device for sampling while drilling formation fluid with low pollution as recited in claim 4, wherein sealing rings are arranged between the outer wall of the piston cylinder and the inner wall of the sampling cylinder and between the outer wall of the balance piston and the inner wall of the sampling cylinder.

6. The device for sampling while drilling formation fluid with low pollution as recited in claim 5, wherein the rear end of the sampling tube is provided with an extended limiting step, and the sampling tube is fixed and positioned by the step inside the outer shell.

7. The device for sampling while drilling formation fluid with low pollution as recited in claim 6, wherein the rear end of the motor is connected with a wire plug at the front end of the power supply cabin, and the front end of the motor is connected with the speed reducer through threads.

8. The device for sampling while drilling formation fluid with low pollution of claim 7, wherein the balance piston is separated from the front end of the piston cylinder by a certain distance.

9. The device for sampling formation fluid while drilling with low pollution of any one of claims 1 to 8, wherein the first one-way valve, the second one-way valve and the third one-way valve are remotely controlled to be opened and closed by the ground.

10. The device for sampling formation fluid while drilling with low pollution as recited in any one of claims 2-8, wherein the motor is directly powered by a battery and remotely controlled from the surface.

11. The device for sampling formation fluid while drilling with low pollution as recited in any one of claims 1-8, wherein the inner cavity of the piston cylinder is connected with the ball screw through threads, and the ball screw drives the piston cylinder to linearly reciprocate through the threads when rotating forwards or reversely.

12. The device for sampling formation fluid while drilling with low pollution as recited in any one of claims 1-8, wherein the cavity between the piston cylinder and the balance piston inside the sampling cylinder is filled with buffer solution and keeps a certain hydraulic pressure, and the cavity between the balance piston and the lower end of the sampling cylinder is not filled with liquid.