Logging instrument piston pressure balancing device structure

Abstract

The utility model discloses a piston pressure balancing device structure of a logging instrument, which relates to the field of oil logging and comprises a piston component, a piston shell, a piston shaft and a tension spring. The inner side of the piston shell is in butt joint with a piston shaft, and the upper and lower ends of the piston shell and the piston shaft are in sealed connection with the array induction body. The piston assembly is annular, an inner hole of the piston assembly penetrates through the outer wall of the piston shaft, the outer wall of the piston assembly is attached to an inner hole of the piston shell, and the piston assembly, the piston shell and the piston shaft are sealed through the second sealing ring. The piston pressure balancing device structure of the logging instrument provides a solution for balancing the internal pressure and the external pressure of the array induction logging instrument in an extreme environment. Through the design scheme, the capacity of adjusting internal and external pressure of the array induction instrument is greatly improved, irreversible damage to the instrument in an extreme environment is avoided, and the application range of the instrument is expanded; meanwhile, the piston pressure balancing device is convenient to maintain, and the use efficiency of instruments is greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of petroleum well logging, in particular to a piston pressure balance device structure of a well logging instrument. Background Art

[0002] Oil and gas resources are very important energy sources in the process of social and economic development. At present, the exploitation of many oil and gas fields in my country has reached the late development stage. The growth rate of oil extraction has slowed down and the difficulty of extraction has continued to increase. The increase in the difficulty of extraction is mainly reflected in the well conditions. With the increase in the depth of the oil well, the temperature and pressure indicators of the logging are also increasing. Well conditions with ultra-high temperature, ultra-high pressure or both ultra-high temperature and ultra-high pressure often occur. In order to improve the efficiency of oil and gas resource exploitation in my country, higher requirements are also put forward for the use indicators of logging instruments.

[0003] Array induction logging instruments have the functions of dividing thin strata and determining the invasion characteristics of flushing zones in oil and gas exploration. Its logging has the advantages of intuitive imaging, high vertical resolution and adaptability to a variety of complex well conditions. It is an indispensable and important part of the field of oil exploration instruments. In order to cope with the continuous increase in my country's logging indicators, it is imperative to optimize and upgrade array induction logging instruments. The pressure balance device that maintains the balance of pressure inside and outside the instrument is the basis for the normal use of the instrument.

[0004] Existing array sensing instruments have poor ability to regulate internal and external pressures, which may cause irreversible damage to the instruments in extreme environments. The application range of the instruments is limited. At the same time, the piston pressure balance device is inconvenient to maintain, which reduces the efficiency of instrument use. Utility Model Content

[0005] The purpose of the utility model is to provide a piston pressure balance device structure for a well logging instrument to solve the problems mentioned in the above background technology that the internal and external pressure capabilities are poor, irreversible damage to the instrument will be caused in extreme environments, the application range of the instrument is limited, and the piston pressure balance device is inconvenient to maintain, which reduces the efficiency of instrument use.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a logging instrument piston pressure balance device structure, including a piston assembly, a first cavity, a mud port, a piston housing, a piston shaft and a tension spring;

[0007] The inner side of the piston shell is butted with a piston shaft, and the upper and lower ends of the piston shell and the piston shaft are sealed and connected to the array sensing body;

[0008] The piston assembly is annular, and the inner hole of the piston assembly passes through the outer wall of the piston shaft, and the outer wall of the piston assembly fits the inner hole of the piston shell, and the piston assembly, the piston shell and the piston shaft are sealed by the second sealing ring;

[0009] The piston assembly consists of a piston body, a safety pressure relief valve, a first sealing ring, an outer scraper ring, an inner scraper ring and a second sealing ring.

[0010] Furthermore, the piston assembly, the piston housing and the piston shaft form two cavities, the first cavity on the left side is used as an oil cavity, and the mud port is opened at the piston housing of the second cavity on the right side, so that the second cavity is used as a mud connection point outside.

[0011] Furthermore, a safety pressure relief valve is installed on the end face of the piston assembly on the second cavity side, and the tension spring is installed on the end face of the piston assembly on the first cavity side. One end of the tension spring is connected to the array sensing body and the other end is connected to the piston assembly to assist the piston assembly in axial reciprocating motion.

[0012] Furthermore, the piston body is in a hollow ring shape, and two outer sealing grooves are designed on the outer ring, an outer mud ring groove is designed on the right side of the outer sealing groove, and an oil hole is provided between the two outer sealing grooves;

[0013] An inner sealing groove is designed at the inner ring of the piston body, an inner mud retaining ring groove is arranged on the right side of the inner sealing groove, a mounting ring groove for a tension spring is arranged at the inner hole at one end of the piston body, and a mounting threaded hole for a safety pressure relief valve is arranged on the other end face of the piston body.

[0014] Furthermore, the first sealing ring is installed in the outer sealing groove, and the second sealing ring is installed in the inner sealing groove. The first sealing ring and the second sealing ring isolate the silicone oil in the first cavity from the mud in the second cavity, and the oil hole allows the space between the two first sealing rings to be filled with silicone oil;

[0015] The outer scraper ring is installed in the outer mud retaining ring groove, and the inner scraper ring is installed in the inner mud retaining ring groove. When the piston body performs axial reciprocating motion, the outer scraper ring and the inner scraper ring clean the mud on the inner hole of the piston shell at the second cavity and the outer shaft surface of the piston shaft.

[0016] Furthermore, a safety pressure relief valve is sealed and installed in the threaded hole at the end surface of the piston body.

[0017] Compared with the prior art, the beneficial effects of the utility model are:

[0018] The piston pressure balance device structure of the logging instrument provides a solution for balancing the internal and external pressures of the array induction logging instrument in extreme environments. Through this design, the ability of the array induction instrument to adjust the internal and external pressures is greatly increased, which avoids irreversible damage to the instrument in extreme environments and expands the application range of the instrument. At the same time, the piston pressure balance device is easy to maintain and greatly improves the efficiency of instrument use.

[0019] Furthermore, a piston is used to adjust the oil chamber space inside the instrument to achieve pressure balance inside and outside the instrument. A safety pressure relief valve is designed inside the piston to enable the instrument to be used normally in a low-pressure and ultra-high-temperature environment, thereby improving the stability of the instrument.

[0020] Furthermore, a tension spring is provided on the end surface of the piston to assist the piston in reciprocating motion, thereby improving the stability of the pressure balance between the inside and outside of the instrument. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the front cross-sectional structure of the utility model;

[0022] Figure 2 This is a schematic diagram of the front cross-sectional structure of the safety pressure relief valve of the utility model;

[0023] Figure 3 This is a schematic diagram of the front cross-sectional structure of the first sealing ring of the utility model;

[0024] Figure 4 It is a schematic diagram of the front cross-sectional structure of the second cavity of the utility model.

[0025] In the figure: 1. piston assembly; 2. piston housing; 3. piston shaft; 4. tension spring; 101. first cavity; 102. second cavity; 103. mud port; 31. threaded hole; 32. mounting ring groove; 33. outer sealing groove; 34. inner sealing groove; 35. inner mud retaining ring groove; 36. outer mud retaining ring groove; 37. oil hole; 11. piston body; 12. safety pressure relief valve; 13. first sealing ring; 14. outer scraper ring; 15. inner scraper ring; 16. second sealing ring. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] Example 1: Please refer to Figure 1-4 The present invention provides the following technical solutions: a well logging instrument piston pressure balance device structure, comprising a piston housing 2 with a piston shaft 3 docked inside, and the upper and lower ends of the piston housing 2 and the piston shaft 3 are sealed and connected to an array sensing body;

[0028] The piston assembly 1 is annular, and the inner hole of the piston assembly 1 passes through the outer wall of the piston shaft 3, and the outer wall of the piston assembly 1 fits the inner hole of the piston housing 2. The piston assembly 1 and the piston housing 2 and the piston shaft 3 are sealed by a second sealing ring 16;

[0029] The piston assembly 1, the piston housing 2 and the piston shaft 3 form two cavities. The first cavity 101 on the left side is used as an oil cavity. The piston housing 2 of the second cavity 102 on the right side is provided with a mud port 103, which connects the second cavity 102 to the external mud. A safety pressure relief valve 12 is installed on the end face of the piston assembly 1 on the second cavity 102 side, and a tension spring 4 is installed on the end face of the piston assembly 1 on the first cavity 101 side. One end of the tension spring 4 is connected to the array induction body, and the other end is connected to the piston assembly 1, which assists the piston assembly 1 in axial reciprocating motion.

[0030] Embodiment 2:

[0031] On the basis of the first embodiment, a piston assembly 1 is also disclosed, and its specific structure is as follows:

[0032] The piston assembly 1 is composed of a piston body 11 , a safety pressure relief valve 12 , a first sealing ring 13 , an outer scraper ring 14 , an inner scraper ring 15 and a second sealing ring 16 .

[0033] The piston body 11 is in the shape of a hollow ring, with two outer sealing grooves 33 designed on the outer ring, an outer mud retaining ring groove 36 designed on the right side of the outer sealing groove 33, and an oil hole 37 arranged between the two outer sealing grooves 33; an inner sealing groove 34 is designed on the inner ring of the piston body 11, and an inner mud retaining ring groove 35 is arranged on the right side of the inner sealing groove 34, a mounting ring groove 32 for the tension spring 4 is arranged at the inner hole at one end of the piston body 11, and a mounting threaded hole 31 for the safety pressure relief valve 12 is arranged on the other side face of the piston body 11. The first sealing ring 13 is installed in the outer sealing groove 33, and the second sealing ring 16 is installed in the inner sealing groove 34. The first sealing ring 13 and the second sealing ring 16 separate the silicone oil in the first cavity 101 from the mud in the second cavity 102, and the oil hole 37 allows the space between the two first sealing rings 13 to be filled with silicone oil;

[0034] The outer scraper ring 14 is installed in the outer mud retaining ring groove 36, and the inner scraper ring 15 is installed in the inner mud retaining ring groove 35. When the outer scraper ring 14 and the inner scraper ring 15 perform axial reciprocating motion on the piston body 11, the mud in the inner hole of the piston housing 2 at the second cavity 102 and the outer shaft surface of the piston shaft 3 are cleaned. The threaded hole 31 at the end face of the piston body 11 is sealed with a safety pressure relief valve 12. When the internal oil pressure of the instrument is too high and the piston assembly 1 can no longer continue to adjust the internal and external pressures of the instrument, the silicone oil in the instrument will be ejected from the safety pressure relief valve 12 to continue to balance the instrument. Internal and external pressure, a piston is used to adjust the internal oil chamber space of the instrument to achieve internal and external pressure balance of the instrument. A safety pressure relief valve 12 is designed inside the piston to enable the instrument to be used normally in a low-pressure and ultra-high temperature environment, thereby improving the stability of the instrument. The internal and external pressure balance solution for array induction logging instruments in extreme environments is provided. Through this design, the ability of array induction instruments to adjust internal and external pressures is greatly increased, thus avoiding irreversible damage to the instrument in extreme environments and expanding the application range of the instrument. At the same time, the piston pressure balance device is easy to maintain and greatly improves the efficiency of instrument use.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A well logging tool piston pressure balance device structure, comprising a piston assembly (1), a first cavity (101), a mud port (103), a piston housing (2), a piston shaft (3) and a tension spring (4); Features: The inner side of the piston shell (2) is butt-jointed with a piston shaft (3), and the upper and lower ends of the piston shell (2) and the piston shaft (3) are sealedly connected to the array sensing body; The piston assembly (1) is annular, and the inner hole of the piston assembly (1) passes through the outer wall of the piston shaft (3), and the outer wall of the piston assembly (1) fits the inner hole of the piston housing (2); The piston assembly (1) consists of a piston body (11), a safety pressure relief valve (12), a first sealing ring (13), an outer scraper ring (14), an inner scraper ring (15) and a second sealing ring (16).

2. A logging tool piston pressure balance device structure according to claim 1, characterized in that: The piston assembly (1), the piston housing (2) and the piston shaft (3) form two cavities. The first cavity (101) on the left side serves as an oil cavity. The second cavity (102) on the right side is provided with a mud port (103) at the piston housing (2). The mud port (103) connects the second cavity (102) with external mud.

3. A logging tool piston pressure balance device structure according to claim 2, characterized in that: A safety pressure relief valve (12) is installed on the end surface of the piston assembly (1) on the second cavity (102) side, and a tension spring (4) is installed on the end surface of the piston assembly (1) on the first cavity (101) side. One end of the tension spring (4) is connected to the array sensing body, and the other end is connected to the piston assembly (1), so as to assist the piston assembly (1) in performing axial reciprocating motion.

4. A logging tool piston pressure balance device structure according to claim 3, characterized in that: The piston body (11) is in a hollow ring shape, and two outer sealing grooves (33) are designed on the outer ring. An outer mud ring groove (36) is designed on the right side of the outer sealing groove (33), and an oil hole (37) is provided between the two outer sealing grooves (33); An inner sealing groove (34) is designed at the inner ring of the piston body (11), and an inner mud retaining ring groove (35) is arranged on the right side of the inner sealing groove (34). A mounting ring groove (32) for a tension spring (4) is arranged at the inner hole at one end of the piston body (11), and a mounting threaded hole (31) for a safety pressure relief valve (12) is arranged on the other end surface of the piston body (11).

5. A logging tool piston pressure balance device structure according to claim 4, characterized in that: The first sealing ring (13) is installed in the outer sealing groove (33), and the second sealing ring (16) is installed in the inner sealing groove (34). The first sealing ring (13) and the second sealing ring (16) separate the silicone oil in the first cavity (101) from the mud in the second cavity (102), and the oil hole (37) allows the space between the two first sealing rings (13) to be filled with silicone oil. The outer scraper ring (14) is installed in the outer mud retaining ring groove (36), and the inner scraper ring (15) is installed in the inner mud retaining ring groove (35). When the piston body (11) performs axial reciprocating motion, the outer scraper ring (14) and the inner scraper ring (15) clean the mud in the inner hole of the piston shell (2) at the second cavity (102) and the outer shaft surface of the piston shaft (3). The piston assembly (1) is sealed with the piston shell (2) and the piston shaft (3) by the second sealing ring (16).

6. A logging tool piston pressure balance device structure according to claim 5, characterized in that: A safety pressure relief valve (12) is sealed and installed in the threaded hole (31) at the end surface of the piston body (11).

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