CN111042754A

CN111042754A - Well repairing method capable of cleaning whole barrel pump without sleeve pressure unloading

Info

Publication number: CN111042754A
Application number: CN201911352501.5A
Authority: CN
Inventors: 贾晋生; 郝春生; 魏国琴; 季长江; 杨昌永; 常会珍; 田庆玲; 崔宇翔; 陈召英; 王维
Original assignee: Shanxi Jincheng Anthracite Mining Group Co Ltd
Current assignee: Shanxi Jincheng Anthracite Mining Group Co Ltd
Priority date: 2019-12-25
Filing date: 2019-12-25
Publication date: 2020-04-21

Abstract

The invention relates to a coal bed gas exploitation, drainage and exploitation utilization technology, in particular to a method for cleaning a whole cylinder pump of a coal bed gas well in the initial drainage and exploitation stage of the coal bed gas well without sleeve pressure relief. The main idea is as follows: in the conventional coal bed gas well pump inspection, a well head sleeve needs to be pressed and removed, then a pumping rod, an oil pipe, a pump cylinder and a pump cylinder plunger are all lifted out of a shaft, and the pump is inspected and cleaned on the ground and then put into the shaft; according to the invention, the sucker rod and the pump barrel plunger are lifted out under the condition of no pressure relief, the hollow sucker rod is put into the oil pipe to the position of the fixed valve of the pump barrel, the fixed valve, the pump barrel and the oil pipe are cleaned through water circulation, and the pump barrel plunger is cleaned on the ground. The significance of the invention lies in that: 1. the casing pressure is not unloaded, so that the damage to a coal reservoir is effectively avoided, and the later gas production rate is ensured; 2. and an oil lifting pipe is not needed for pump detection, so that the workload is reduced.

Description

Well repairing method capable of cleaning whole barrel pump without sleeve pressure unloading

Technical Field

The invention belongs to the technical field of coal bed gas drainage and production, and particularly relates to a well repairing method capable of cleaning a whole barrel pump without removing casing pressure.

Background

According to the coal bed gas well development theory summarized by the predecessor, the core is drainage and pressure reduction, and the drainage and production process is continuous and stable, so that the damage to a coal reservoir can be reduced, the coal bed cracks can be effectively communicated, and the productivity of the coal bed gas well is maximized. The coal bed gas well drainage and production equipment is various and comprises a pumping unit matched with a whole barrel pump, a screw pump, a gas lift and other modes, the common drainage and production mode is a combination of the pumping unit matched with the whole barrel pump, at the initial drainage and production stage of the coal bed gas well, along with the prolonging of drainage and production time, the coal bed spitting powder and other phenomena occur, the pumping efficiency of the drainage and production pump can be reduced, the requirement of drainage and production cannot be met, at the moment, the pump needs to be checked, the well mouth sleeve pressure blowout is required to be carried out according to the precondition of checking the pump, if gas is produced all the time, well killing is carried out, then, underground pipe columns are all lifted out, and the pump is cleaned and maintained. The continuous and stable theory of operation and drainage is opposite to that of production, after well workover and recovery operation, the gas production needs to be recovered for a long time, in soft and hypotonic areas, the gas production of many wells cannot be recovered, and the productivity of the coal-bed gas well is greatly influenced.

The above conditions are contradictory problems, the pump efficiency of the drainage and production pump is reduced, the drainage and production requirements cannot be met, and well workover is needed, but the casing pressure is inevitably removed during well workover, so that the coal reservoir is damaged, and the productivity of the coal-bed gas well is influenced. Therefore, a well repairing method which can clean and maintain the coal bed methane extraction plunger pump without unloading casing pressure is needed.

Disclosure of Invention

The invention aims to provide a well repairing technology, which is used for detecting a pump of a coal bed gas extraction whole cylinder pump under the condition of not removing casing pressure.

In order to achieve the purpose, the invention provides a well repairing method capable of cleaning a whole barrel pump without removing casing pressure.

Further, the well repairing method capable of cleaning the whole barrel pump without removing casing pressure specifically comprises the following steps:

1) the workover locomotive is transported to a coal bed gas well site to be repaired, a workover derrick is erected, an oil pipe bridge (used for placing an oil pipe and a sucker rod) is erected, and an instrument is disassembled;

2) disassembling the polish rod sealing box (sealing the space between the polish rod and the oil pipe), lifting the sucker rod and the pump barrel plunger in the oil pipe, and checking and cleaning on the ground;

3) a hollow sucker rod is put into the oil pipe to a fixed valve of the pump barrel, and the hollow sucker rod and the oil pipe are sealed by a sucker rod sealing box;

4) connecting a booster pump and a hollow sucker rod by using a high-pressure water pipe, starting the booster pump, injecting water in a water tank into the hollow sucker rod by using the booster pump, enabling the water to flow out of the bottom of the hollow sucker rod to scour the inner walls of a fixed valve, a pump cylinder, an oil pipe and the like, returning to the ground from an annular space between the oil pipe and the hollow sucker rod, and discharging from a drainage valve, so that impurities such as coal dust, sand and the like at the fixed valve at the lower part of the pump cylinder are taken out, and performing circulating cleaning work until the returned water becomes clear and has no impurities;

5) and after cleaning, the hollow sucker rod is put out, cleaning or replacement is selected according to the abrasion condition of the plunger of the pump cylinder, and the sucker rod is put into the sucker rod string to complete well repair and resume production.

3. The well repairing method of the whole barrel pump capable of being cleaned without casing pressure removal as claimed in claim 2, wherein the hollow sucker rod has an outer diameter of 30mm, an inner diameter of 20mm and a length of 10 m.

Compared with the prior art, the invention has the advantages that:

according to the well repairing method capable of cleaning the whole barrel pump without sleeve pressure unloading, provided by the invention, the pressure between an oil pipe and a production sleeve is not required to be unloaded when the pump barrel is cleaned, so that the damage to a coal reservoir fracture system caused by well repairing is reduced, and the productivity of a coal-bed gas well is influenced. The invention can realize the cleaning of the fixed valve under the conditions of not lifting the oil pipe and not unloading the casing pressure, thereby effectively saving the well repairing time.

Drawings

FIG. 1 is a schematic view of a hollow sucker rod being lowered into an oil pipe.

Fig. 2 is a schematic diagram of a surface equipment connection.

In the figure: 1-producing a casing; 2-hollow sucker rod; 3-oil pipe; 4-fixing the valve ball; 5-sieve tube; 6-pump cylinder; 7-a water tank; 8-a booster pump; 9-high pressure water pipe; 10-polish rod sealing box; 11-a drain valve.

Detailed Description

The invention is described in detail below with reference to the accompanying drawings:

as shown in fig. 1 and 2, a well repairing method capable of cleaning a whole barrel pump without removing casing pressure specifically comprises the following steps:

1) the workover locomotive is transported to a coal bed gas well site to be repaired, a workover derrick is erected, an oil pipe bridge is erected, and an instrument is disassembled.

2) The polish rod sealing box 10 is disassembled, the sucker rod and the pump barrel plunger in the oil pipe 3 are lifted, and the ground is inspected and cleaned.

3) The hollow sucker rod 2 is put into the oil pipe 3 to the fixed valve position in the pump barrel 6, and the hollow sucker rod 2 and the oil pipe 3 are sealed by the sucker rod sealing box 10.

4) Use high pressure water pipe 9 to be connected booster pump 8 and hollow sucker rod 2, start booster pump 8, booster pump 8 pours into hollow sucker rod 2 with the water in the water tank 7 in, water flows out to fixed valve 4 from hollow sucker rod 2 bottom, pump barrel 6, inner wall such as oil pipe 3 erodees, return to ground from drain valve 11 and discharge in the annular space between oil pipe 3 and hollow sucker rod 2, thereby take out the impurity such as buggy, sand of 6 lower part fixed valve 4 departments of pump barrel, cleaning work is until the water that returns becomes clear and is free of impurity.

5) And after cleaning, the hollow sucker rod 2 is put out, cleaning or replacement is selected according to the abrasion condition of the pump barrel plunger, and the sucker rod string is put into the hollow sucker rod 2 to complete well repair and resume production.

The hollow sucker rod 2 has an outer diameter of 30mm, an inner diameter of 20mm and a length of 10 m.

According to the well repairing method capable of cleaning the whole barrel pump without removing casing pressure, the hollow sucker rod is utilized to reach the fixed valve at the lowest part of the down-pipe column pump barrel of the coal-bed gas well from the inside of the oil pipe, then the booster pump is utilized to circulate water, the inner walls of the pump barrel, the oil pipe and the like including the fixed valve are cleaned, and the problem that the pump efficiency is seriously reduced due to the fact that the fixed valve is not tightly sealed, garbage is deposited in the pump barrel and the like can be solved.

Claims

1. A well repairing method capable of cleaning a whole barrel pump without removing casing pressure is characterized in that a sucker rod and a plunger of a pump barrel are lifted out, a hollow sucker rod is put into an oil pipe to a fixed valve in the pump barrel, and the fixed valve, the pump barrel and the oil pipe are cleaned through water circulation.

2. The well repairing method for cleaning the whole barrel pump without removing casing pressure according to claim 1, which is characterized by comprising the following steps:

1) the well repairing locomotive is conveyed to a coal bed gas well site to be repaired, a well repairing derrick is erected, an oil pipe bridge is erected, and an instrument is disassembled;

2) disassembling the polish rod sealing box, lifting the sucker rod and the pump barrel plunger in the oil pipe, and checking and cleaning on the ground;

4) connecting a booster pump and a hollow sucker rod by using a high-pressure water pipe, starting the booster pump, injecting water in a water tank into the hollow sucker rod by using the booster pump, enabling the water to flow out of the bottom of the hollow sucker rod to scour the fixed valve, the pump cylinder and the inner wall of an oil pipe, returning to the ground from the annular space between the oil pipe and the hollow sucker rod, and discharging from a drainage valve, so that impurities such as coal dust, sand and the like at the fixed valve at the lower part of the pump cylinder are taken out, and performing circulating cleaning work until the returned water is clear and free of impurities;