CN206571462U - A kind of Multifunctional underwell valve - Google Patents

Abstract

The utility model discloses an underground multifunctional valve, which is used for back-sealing of packers in the construction process of oil, gas and water wells and can realize rapid acid replacement operation. The utility model includes a piston and a valve body. The pipe body of the center pipe is provided with a liquid flow channel, and the upper part is connected with the upper joint. The valve body is fixed on the lower part of the center pipe through the valve body shear pins to block the liquid flow channel on the pipe body. The utility model can simultaneously realize the seal inspection and acid replacement operation for the acidizing string with the packer in the acidizing construction of the well with deep formation and poor formation absorption performance, which ensures the sealing performance of the packer and reduces the Reduce construction risks and improve construction efficiency. The utility model has the advantages of simple structure and convenient use, which avoids the troubles caused by the inability to check the seal of the packer and pollute the formation in the prior art, and has remarkable use effect and remarkable economic benefits.

Description

A Downhole Multifunctional Valve

technical field

The utility model belongs to downhole operation tools in the petroleum industry, in particular to a downhole multifunctional valve, which is used for reverse sealing of packers in the construction process of oil, gas and water wells and can realize rapid acid replacement operation.

Background technique

Acidizing construction is a common process for oil and gas reservoir reconstruction. The method is to squeeze acid liquid into the formation, and form pores by chemical reaction between the acid liquid and certain substances in the formation, improve the circulation capacity of the formation, and increase the productivity of oil and gas wells. The existing method is as follows: 1. Set the packer near the target layer to isolate the damage to casing and wellhead device by high-pressure fluid, and then inject acid liquid from oil pipe to construct the formation. The problem is that many wells are deep or the formation itself has weak liquid absorption capacity. Before the acid liquid squeezes into the formation, the liquid in the wellbore needs to be squeezed into the formation in advance, resulting in protracted construction time and increased construction difficulty and risk. And cause pollution to the stratum, bring negative influence to follow-up production. 2. The upper part of the packer is connected to the normally open valve, and after the tool is lowered in place, set the packer, replace the acid, and drop the ball to close the normally open valve for acidizing construction. Although this method can quickly replace acid fluid, it cannot verify the sealing effect of the packer, and serious consequences will be brought about if the packer is not set tightly.

Contents of the invention

The purpose of the utility model is to provide a downhole multi-functional valve, which overcomes the fact that in the acidizing construction of wells with deep formations and poor formation absorption performance, the sealing and acid replacement operations cannot be realized at the same time for the acidizing string with a packer. problems, reduce construction risks and improve construction efficiency.

The technical solution of the utility model is: a downhole multifunctional valve includes a piston and a valve body, the body of the central pipe is provided with a liquid flow channel, the upper part is connected with the upper joint, and the two ends of the piston pass through the ball seat scissors and the piston. The shear pins are respectively connected with the inner ball seat and the central pipe, and the valve body is fixed on the lower part of the central pipe through the valve body shear pins to block the liquid flow channel on the pipe body.

Compared with the prior art, the remarkable application effect of the utility model lies in that the utility model can simultaneously realize sealing inspection for the acidizing string with the packer in the acidizing construction of wells with deep layers and poor formation absorption performance. And replace the acid operation to ensure the tightness of the packer, reduce the construction risk and improve the construction efficiency. The utility model has the advantages of simple structure and convenient use, which avoids the trouble caused by the inability to check the seal of the packer and pollute the stratum in the prior art, has remarkable use effect and remarkable economic benefits.

Description of drawings

Fig. 1 is the structural representation of the utility model.

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings, not to limit the protection scope of the present invention, and all improvements obtained by using the design idea of the present invention belong to the protection scope of the present invention.

Referring to Fig. 1, a downhole multi-function valve includes a piston 6 and a valve body 9, the body of the center pipe 7 is provided with a liquid flow channel, the upper part is connected with the upper joint 1, and the two ends of the piston 6 pass through the ball seat shear nail 4 and The piston scissors 8 are respectively connected with the inner ball seat 3 and the central tube 7, and the valve body 9 is fixed on the lower part of the central tube 7 by the valve body scissors 11 to block the liquid flow channel on the tube.

The outer circle of the lower part of the upper joint 1 is threadedly connected with the protective sleeve 2, the inner diameter of the protective sleeve 2 is larger than the outer diameter of the valve body 9, the valve body 9 can move freely up and down in the protective sleeve 2, and the protective sleeve 2 can During the downhole process of the tool, the valve body 9 is protected to prevent the valve body 9 from bumping.

The outer circle of the lower part of the central pipe 7 is provided with threads to connect with the oil pipe or packer, and the inner circle below the piston shear hole on the pipe body of the central pipe 7 is provided with a piston anti-drop step and an upper outer circle of the piston shear hole. A valve body is attached to a step, and the liquid flow channel is arranged on the pipe body below the shear nail hole of the piston.

Both sides of the inner ball seat shear hole of the piston 6, the below of the piston shear hole and the top of the valve body shear hole are respectively provided with a piston sealing ring 5 and a valve body sealing ring 10. Also be provided with sealing ring between circle and piston 6.

The inner ball seat 3 is a cylindrical body, the inner circle of the upper end is provided with inner chamfers to cooperate with the sealing balls dropped in, and the lower cylindrical body is provided with assembly holes to facilitate the assembly of the inner ball seat 3 .

The shear force of the ball seat shear pin 4 is greater than the shear force of the piston shear pin 8 .

The using method of the present utility model is as follows:

1. According to the construction design requirements, connect this tool to the required position and run it into the well, set the packer at the designed position, pressurize the oil casing annulus, and perform reverse inspection of the packer, that is, pressurize from the casing to check the packer The condition of the seal.

2. After the packer has passed the seal inspection, it is pressed from the oil pipe. Under the action of the pressure, the valve body 9 generates an axial thrust to cut off the valve body shear pin 11 and then ascends. The liquid flow channel on the center pipe 7 is opened to quickly circulate the acid liquid. to the bottom of the well.

3. After the acid liquid is replaced to the bottom of the well, the sealing ball is put into the oil pipe and falls on the inner ball seat 3. Pressed by the oil pipe, the inner ball seat 3 generates a downward force and transmits it to the piston scissors 8 and cuts the piston scissors 8. The inner ball seat 3 and the piston 6 descend simultaneously to close the liquid flow channel of the central tube 7.

4. The pressure continues to rise, the inner ball seat shear nail 4 is cut off, the sealing ball and the piston fall into the bottom of the well, the oil pipe is connected with the formation, and the acid liquid is squeezed into the formation under the pump pressure to realize acidizing construction.

The embodiments described above are only typical embodiments, but the present invention is not limited to these embodiments, and those skilled in the art can make modifications without departing from the spirit and inspiration of the present invention. There may be many changes, combinations and modifications in the solutions disclosed herein, all of which are within the scope of the present invention. Therefore, the scope of protection is not limited to the above description.

Claims (6)

1. A downhole multifunctional valve, comprising a piston and a valve body, is characterized in that the body of the center pipe is provided with a liquid flow channel, the upper part is connected with the upper joint, and the two ends of the piston pass through the ball seat shear nail and the piston shear nail The valve body is respectively connected with the inner ball seat and the center pipe, and the valve body is fixed on the lower part of the center pipe through valve body shear pins to block the liquid flow channel on the pipe body. 2. A downhole multifunctional valve as claimed in claim 1, characterized in that, the outer circle of the lower part of the upper joint is threadedly connected to the protective sleeve, the inner diameter of the protective sleeve is greater than the outer diameter of the valve body, and the valve body can Free movement up and down in the case. 3. A downhole multifunctional valve as claimed in claim 2, characterized in that, the outer circle of the lower part of the center pipe is provided with threads to connect with the oil pipe or packer, and the piston shear hole on the pipe body of the center pipe The lower inner circle is provided with a piston anti-falling step, the upper outer circle of the piston shear hole is provided with a valve body anchoring step, and the liquid flow channel is arranged on the pipe body below the piston shear hole. 4. A kind of downhole multifunctional valve as claimed in claim 3, characterized in that, the two sides of the inner ball seat shear nail hole of the piston, the bottom of the piston shear nail hole and the top of the valve body shear nail hole respectively set A piston sealing ring and a valve body sealing ring are arranged, and a sealing ring is also arranged between the upper outer circle of the inner ball seat and the piston. 5. A downhole multifunctional valve as claimed in claim 2, characterized in that the inner ball seat is a cylindrical body, the inner circle of the upper end is provided with inner chamfers to cooperate with the sealing ball dropped in, and the lower cylindrical body There are mounting holes on it. 6. A downhole multifunctional valve according to claim 1, characterized in that, the shear force of the ball seat shear pin is greater than the shear force of the piston shear pin.