CN111197463A

CN111197463A - Oscillator

Info

Publication number: CN111197463A
Application number: CN201811375291.7A
Authority: CN
Inventors: 玄令超; 马广军; 王甲昌; 张海平; 臧艳彬; 陶兴华; 刘晓丹; 张仁龙
Original assignee: China Petroleum and Chemical Corp; Sinopec Research Institute of Petroleum Engineering
Current assignee: China Petroleum and Chemical Corp; Sinopec Research Institute of Petroleum Engineering
Priority date: 2018-11-19
Filing date: 2018-11-19
Publication date: 2020-05-26

Abstract

The present invention relates to an oscillator connected between an upper drill and a lower drill, the oscillator comprising: an upper body fixedly connected to the upper drill; and a lower body fixedly connected to the lower drill; wherein relative longitudinal movement and relative circumferential rotation can occur between the upper and lower bodies. The oscillator can effectively reduce the operation cost when being used in the drilling operation of horizontal wells and extended reach wells.

Description

Oscillator

Technical Field

The invention relates to the technical field of drilling, in particular to an oscillator.

Background

As oil and gas resource development is gradually promoted to deep strata, the borehole length of horizontal wells and extended reach wells is continuously increased. In the horizontal or inclined section, the drill string used for drilling is usually brought back into contact with the borehole wall for a long distance under the influence of gravity.

In the prior art, drilling is usually performed by applying longitudinal pressure. Accordingly, the drill bit, and the like are vibrated in the longitudinal direction. However, this results in a very high frictional resistance between the drill string and the borehole wall and thus can lead to drilling difficulties. The drilling difficulty is particularly shown in the aspects of large energy consumption required for drilling, low drilling speed and the like. This undoubtedly greatly prolongs the drilling cycle, significantly increasing the operating costs.

Therefore, an oscillator capable of reducing the operation cost is required.

Disclosure of Invention

In view of the above problems, the present invention provides an oscillator which can effectively reduce the operation cost when used in drilling operation of horizontal wells and extended reach wells.

According to the present invention, there is provided an oscillator connected between an upper drill and a lower drill, the oscillator comprising: an upper body fixedly connected to the upper drill; and a lower body fixedly connected to the lower drill; wherein relative longitudinal movement and relative circumferential rotation can occur between the upper and lower bodies.

Relative longitudinal movement and relative circumferential rotation between the upper and lower bodies enables relative longitudinal movement and relative axial rotation of the upper and/or lower bodies and the upper and lower tools associated therewith relative to the outer wall of the borehole. By this way of movement, the relative movement between the drilling tool and the borehole wall is relatively strong, and thereby the friction between the drilling tool and the borehole wall can be greatly reduced. Therefore, it is possible to perform a relatively high speed drilling operation with a relatively small driving force. This is very useful for shortening the drilling cycle and reducing the operating costs.

In one embodiment, the upper body is at least partially nested within the lower body, wherein a first screw guide is configured on an outer side wall of the upper body, the first screw guide having a longitudinal direction and a circumferential direction component of extension, and a second screw guide mating with the first screw guide is configured on an inner side wall of the lower body, and upon relative longitudinal movement between the upper body and the lower body, relative circumferential rotation between the upper body and the lower body also occurs in cooperation with the first screw guide and the second screw guide.

In one embodiment, at least one piston body is connected at a lower end of the upper body, the at least one piston body is in sealed sliding fit with an inner side wall of the lower body, and a fluid oscillating mechanism is disposed in the lower body below the at least one piston body, the fluid oscillating mechanism being configured to enable a periodic variation in pressure of a fluid passing therethrough, the periodic variation in pressure of the fluid being transmittable to below the at least one piston body to push the at least one piston body.

In one embodiment, the at least one piston body comprises a first piston body and a second piston body arranged spaced apart below the first piston body, the first piston body is directly connected with the lower end of the upper body, a connecting rod extending in the longitudinal direction is arranged between the first piston body and the second piston body, the lower body is configured with a radially inwardly extending bulge spaced apart from the first piston body and the second piston body between the first piston body and the second piston body, the bulge is in sealed sliding fit with the connecting rod, below the first piston body, the inner side wall of the lower body, the bulge and the connecting rod enclose a first pressure chamber, the connecting rod is configured to be hollow, a communication hole communicating with the first pressure chamber is configured on the side wall of the connecting rod, the connecting rod is configured to transmit a pressure of a fluid of the fluid oscillating mechanism into the first pressure chamber, a first balance chamber is formed above the first piston body, a first communication hole communicating the first balance chamber with an external environment is configured on a sidewall of the lower body, a second pressure chamber is formed below the second piston body, the pressure of the fluid oscillating mechanism can be transmitted into the second pressure chamber, a second balance chamber is surrounded by the connecting rod, the boss and an inner sidewall of the lower body above the second piston body, and a second communication hole communicating the second balance chamber with the external environment is configured on the sidewall of the lower body.

In one embodiment, the fluid oscillation mechanism comprises: a fixed valve plate fixedly disposed in the lower body, the fixed valve plate being configured with a fixed flow through hole penetrating the fixed valve plate in a longitudinal direction; and a rotary valve plate rotatable about the longitudinal axis of the lower body, which rotary valve plate is arranged adjacent to the stationary valve plate on the side of the stationary valve plate facing the at least one piston body, on which rotary valve plate rotary flow through holes are configured which extend through the rotary valve plate in the longitudinal direction; wherein the fixed flow hole and the rotary flow hole are configured to be eccentrically disposed with respect to a longitudinal axis of the lower body, and an area of a portion where the fixed flow hole and the rotary flow hole overlap periodically changes when the rotary valve plate rotates.

In one embodiment, the stationary flow opening and the rotary flow opening have a maximum overlapping area in the first state, which is equal to the area of the stationary flow opening and/or the rotary flow opening; and/or the stationary flow opening and the rotary flow opening have a minimum overlapping area in the second state, the ratio of the minimum overlapping area to the area of the stationary flow opening and/or the rotary flow opening being between 0.1 and 0.5, preferably between 0.2 and 0.3.

In one embodiment, the fluid oscillating mechanism further comprises an inner conduit fixedly attached above the rotary valve plate, the inner conduit communicating to the inner cavity of the upper body and the at least one piston body, and is communicated with the rotary flow through hole on the rotary valve plate, the inner pipeline is sleeved in the lower main body and is spaced from the lower main body, an annular cavity is formed between the inner pipe and the lower body, upper and lower through holes penetrating through a sidewall of the inner pipe are respectively formed at upper and lower ends of the inner pipe, the through holes communicating an inner space of the inner pipe with the annular cavity, a drive turbine assembly is disposed between the upper through hole and the lower through hole in the annular cavity, the drive turbine assembly is configured to rotate the inner conduit in response to fluid flowing therethrough.

In one embodiment, the fluid oscillation mechanism further comprises an oscillation amplifier disposed within the lower body above the inner conduit, the oscillation amplifier configured to amplify and transfer oscillations of the fluid from the inner conduit to the at least one piston body.

In one embodiment, above the first piston body, the lower body is configured with a step surface facing downward, and a disc spring set is arranged between the step surface and the first piston body, and the disc spring set is configured to push the first piston body to move away from the step surface when the first piston body approaches the step surface.

In one embodiment, the upper body includes a first section and a second section extending downwardly from the first section, the first section having an outer diameter greater than an outer diameter of the second section, a first abutment surface facing downwards is formed at the junction between the first section and the second section, a second resisting surface which can be matched with the resisting surface is formed on the inner side of the lower main body, a clamping part is embedded in the outer side wall of the second section of the upper main body, the clamping part radially extends outwards to protrude out of the outer side wall of the second section, a groove for accommodating the clamping portion is formed on the inner side wall of the lower main body, the distance between the upper side wall and the lower side wall of the groove is greater than the length of the clamping portion, when the first resisting surface is contacted with the second resisting surface, a gap is formed between the clamping part and the upper side wall of the groove.

Compared with the prior art, the invention has the advantages that: relative longitudinal movement and relative circumferential rotation between the upper and lower bodies enables relative longitudinal movement and relative axial rotation of the upper and/or lower bodies and the upper and lower tools associated therewith relative to the outer wall of the borehole. By this way of movement, the relative movement between the drilling tool and the borehole wall is relatively strong, and thereby the friction between the drilling tool and the borehole wall can be greatly reduced. Therefore, it is possible to perform a relatively high speed drilling operation with a relatively small driving force. This is very useful for shortening the drilling cycle and reducing the operating costs.

Drawings

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

fig. 1 shows the structure of an oscillator according to an embodiment of the present invention;

FIG. 2 shows an enlarged view of a portion of the oscillator of FIG. 1;

FIG. 3 shows an enlarged view of another portion of the oscillator of FIG. 1;

FIG. 4 shows the structure of an upper body according to an embodiment of the present invention; and is

Fig. 5 shows the structure of the second piston body and the connecting rod according to one embodiment of the invention.

In the drawings, like parts are provided with like reference numerals. The figures are not drawn to scale.

Detailed Description

The invention will be further explained with reference to the drawings.

Fig. 1-3 show an embodiment of an oscillator 1 according to the invention, wherein fig. 2 and 3 each show an enlarged view of a part of the oscillator 1 in fig. 1.

As shown in fig. 1 to 3, the oscillator 1 includes a substantially cylindrical upper body 10 and a substantially cylindrical lower body 20. In the illustrated embodiment, the lower body 20 is constructed of a plurality of parts including a guide housing 21, an auxiliary housing 22, a first piston housing 23, a second piston housing 24, an oscillation housing 25, and a lower joint 26, which are fixedly connected in this order from top to bottom. However, it should be understood that lower body 20 may be constructed from more separate components, or one or more of the above components may be integrally formed, as desired.

The upper body 10 includes an upper joint for connection to an upper drill, a first section 11 connected below the upper joint, and a second section 12 connected below the first section 11. As shown in fig. 4, a first guide 111 may be configured on the outer side wall of the first section 11 and a matching second guide (not shown) may be configured on the corresponding inner wall of the guide housing 21. The first guide 111 is configured as a spiral having a path extending in a longitudinal direction and a circumferential direction. The first guide 111 and the second guide are slidably engaged with each other when the first section 11 is fitted in the guide housing 21. Thereby, when the upper body 10 moves in the longitudinal direction relative to the lower body 20, relative circumferential rotation between the upper body 10 and the lower body 20 can occur under the cooperation of the first guide and the second guide.

In a preferred embodiment shown in fig. 4, the first guide 111 may be formed as a helical spline. The helical spline may be formed by grooving the first section 11. The first guide 111 preferably extends to the end face where the first section 11 is connected to the second section 12.

The outer diameter of the first section 11 is greater than the outer diameter of the second section 12, and a downwardly facing abutment surface is formed at the connection between the first section 11 and the second section 12. The guide housing 21 is configured with a corresponding abutment face facing upwards. When the abutment surfaces of the guide housing 21 and the first section 11 are in contact with each other, the upper body 10 is in a lowermost position with respect to the lower body 20.

The outer side wall of the second section 12 can be embedded with a clamping portion 123, and the clamping portion 123 extends radially outwards to protrude out of the outer side surface of the second section 12. The lower end of the guide housing 21 and the auxiliary housing 22 enclose a groove 213 for accommodating the catching portion 123. As shown in fig. 2, the length of the groove 213 (i.e., the distance between the upper and lower sidewalls of the groove 213) is greater than the length of the catching portion 123. The upper side wall of the groove 213 is spaced apart from the catching portion 123 when the upper body 10 is at the lowermost position with respect to the lower body 20. Thereby, the upper body 10 is allowed to move upward relative to the lower body 20 with the catching portion 123 until the catching portion 123 comes into contact with the upper side wall of the groove 213. By this arrangement, the range of movement of the upper body 10 relative to the lower body 20 in the longitudinal direction can be restricted.

As shown in fig. 2, the upper body 10 further includes a third section 13 extending downward from the second section 12. A first piston body 31 is fixedly connected to the lower end of the third section 13 through threads. The first piston body 31 is in sealed sliding engagement with the inner side wall of the first piston housing 23. Above the first piston body 31, a first balance chamber 41 is formed enclosed between the lower end of the sub-housing 22, the first piston housing 23, and the upper body 10. Preferably, an elastic member 30 is disposed in the first balance chamber 41, and one end of the elastic member 30 abuts against the first piston body 31 and the other end abuts against the lower end surface of the auxiliary housing 22. The elastic member 30 is preferably a disc spring assembly. Such elastic member 30 has good rigidity and restorability, and is advantageous for extending the service life of the oscillator 1.

A connecting rod 32 extending in the longitudinal direction is connected to a lower portion of the first piston body 31, and a second piston body 33 is fixedly connected to a lower portion of the connecting rod 32 by a screw. The second piston body 33 is in sealed sliding engagement with the inner side wall of the second piston housing 24. The lower end of the first piston body 23 projects radially inwardly to form a projection 233. The projection 233 is in sealed sliding engagement with the connecting rod 32. Thereby, the first pressure chamber 42 can be formed below the first piston body 31 under the surrounding of the bulging portion 233, the inner side wall of the first piston housing 23, and the connecting rod 32. A second balance chamber 43 may be formed above the second piston body 33 under the enclosure of the protrusion 233, the inner sidewall of the second piston housing 24, and the connecting rod 32. A second pressure chamber 44 is formed in the second piston housing 24 below the second piston body 33.

It will be appreciated that in the embodiment shown in figures 1-3, a two-stage piston arrangement is provided. However, only a single-stage piston structure or a more-stage piston structure (e.g., 3-stage, 4-stage, or 5-stage, etc.) may be provided as necessary.

Below this second pressure chamber 44, the oscillator 1 further comprises a fluid oscillation mechanism. The fluid oscillating mechanism is configured to communicate with the fluid passages in the upper body 10, the first piston body 31, the connecting rod 32, and the second piston body 33, and the second pressure chamber 44. A pressure communication hole 321 is opened at an upper end of the connecting rod 32 through a side wall thereof to communicate the first pressure chamber 42 with a fluid passage in the connecting rod 32. The drilling fluid can flow into the fluid oscillation mechanism from top to bottom through the fluid channel. The fluid oscillating mechanism is capable of oscillating, i.e. changing the pressure of, the drilling fluid therein. A change in the fluid pressure in the fluid oscillating mechanism can cause a corresponding change in the pressure in the first and

second pressure chambers

42, 44 communicating therewith to urge the first and

second piston bodies

31, 33 upward.

Here, the first balance chamber 41 may communicate with the external environment through a first communication hole 231 configured on a side wall of the first piston housing 23. The second balancing chamber 43 can communicate with the external environment through a second communication hole 241 constructed on the side wall of the second piston housing 24. Thereby, the pressure inside the first equalizing chamber 41 and the second equalizing chamber 43 may be substantially constant.

As shown in fig. 5, the connecting rod 32 may be integrally formed with the second piston body 33. Two rows of pressure communication holes 321 are provided in the side wall of the connecting rod 32.

Referring to fig. 3, the fluid oscillating mechanism disposed below the second pressure chamber 44 includes a fixed valve plate 82 fixedly disposed on the lower joint 26 and surrounded by the inner wall of the oscillating case 25, and a rotary valve plate 81 disposed above the fixed valve plate 82. The rotary valve plate is accommodated in the oscillation housing 25 and is rotatable about the longitudinal axis of the oscillator 1. The rotary valve plate 81 is provided with a rotary flow hole 811 that penetrates the rotary valve plate 81 in the longitudinal direction. Accordingly, a fixed flow hole 821 penetrating the fixed valve plate 82 in the longitudinal direction is provided in the fixed valve plate 82. The rotary flow hole 811 communicates with the fixed flow hole 821 and with the flow passage in the upper second piston chamber 44 and the lower joint 26. Also, the rotary valve plate 81 and the fixed valve plate 82 are configured such that the area of the rotary flow hole 811 communicating with the fixed flow hole 821 varies with the rotation of the rotary valve plate 81. In this manner, the flow rate and pressure of the fluid therein may be periodically varied as the rotary valve plate 81 rotates, and thereby the fluid is oscillated to generate corresponding low and high pressure pulse signals. The oscillation can be transmitted to the first and

second pressure chambers

42, 44 above, respectively.

In the embodiment shown in fig. 3, the rotary valve plate 81 is directly placed on the fixed valve plate 82, whereby the area where the rotary flow through hole 811 communicates with the fixed flow through hole 821 can be changed by adjusting the area where the rotary flow through hole 811 overlaps with the fixed flow through hole 821. For example, to this end, the rotating flow bore 811 and the stationary flow bore 821 may each be disposed eccentrically with respect to the longitudinal axis. Preferably, in the first state, the rotational flow hole 811 and the fixed flow hole 821 are completely overlapped. At this time, the flow area between the rotating flow hole 811 and the fixed flow hole 821 is maximized, and accordingly, a low-pressure pulse signal is generated with respect to the fluid. In the second state, the rotating flow hole 811 and the fixed flow hole 821 are only partially overlapped. At this time, the flow area between the rotating flow hole 811 and the fixed flow hole 821 is minimized, and accordingly, a high-voltage pulse signal is generated with respect to the fluid. In the second state, the ratio of this smallest overlapping area (flow area) to the area of the stationary flow openings and/or the rotating flow openings is between 0.1 and 0.5, preferably between 0.2 and 0.3. Within this range, oscillation can be most effectively induced without significantly affecting the flow of drilling fluid to the lower drill string.

In addition, the fluid oscillation mechanism may include an inner conduit 61 disposed between the rotary valve plate 81 and the second pressure chamber 44. The inner pipe 61 is fixedly connected to the rotary valve plate 81, and an inner passage of the inner pipe communicates with the rotary flow hole 811 of the rotary valve plate 81. The internal passage of the inner conduit is in turn in communication with the second pressure chamber 44. The inner pipe 61 is fitted in the oscillation housing 25 and spaced apart from the oscillation housing 25 to form an annular cavity therebetween. At the upper end of the inner pipe 61, an upper through hole 611 is configured which penetrates the inner pipe 61 in the radial direction to communicate the inner channel of the inner pipe 61 with the annular cavity. At the lower end of the inner pipe 61, a lower through hole 612 is configured which penetrates the inner pipe 61 in the radial direction to communicate the inner channel of the inner pipe 61 with the annular cavity. The lower through hole 612 preferably has an extension component in the longitudinal direction such that it is gradually inclined downward in a generally radially inward direction. Thereby, a small portion of the fluid flowing into the inner pipe 61 may flow into the annular chamber through the upper through hole 611 and flow back into the inner pipe 61 through the lower through hole 612. Within the annular cavity may be disposed a drive turbine assembly 90. Drive turbine assembly 90 includes an upper stationary bearing sleeve 92 and a lower stationary bearing sleeve 95 that are fixed relative to oscillating housing 25. Drive turbine assembly 90 further includes an upper movable bearing sleeve 91 and a lower movable bearing sleeve 94, which are fixed relative to inner conduit 61 and rotatably received within an upper stationary bearing sleeve 92 and a lower stationary bearing sleeve 95, respectively. A driving turbine stator and rotor 93 are provided between the upper stationary bearing sleeve 92 and the upper movable bearing sleeve 91 and the lower stationary bearing sleeve 95 and the lower movable bearing sleeve 94. The stator is fixed with respect to the oscillating casing 25 and the rotor is fixed with respect to the inner pipe 61. As the fluid flows through the drive turbine stator and rotor 93, the rotor can be caused to rotate relative to the stator and thereby cause the inner conduit 61 and the rotary valve plate 81 to rotate.

It will be appreciated that the construction of the drive turbine stator and rotor 93 itself is well known to those skilled in the art and will not be described in detail herein.

Preferably, an oscillator amplifier 50 is also arranged between the inner tube 61 and the second pressure chamber 44. The oscillator amplifier 50 is used to amplify the high-voltage pulse signal and the low-voltage pulse signal from the rotary valve plate 81, so that the high-voltage pulse signal and the low-voltage pulse signal can act on the piston body to drive the piston body to move. For example, the oscillator amplifier 50 may be a self-excited amplifier having a cavity therein that enables superposition, resonance, and amplification of pressure pulses. The structure of the self-excited amplifier itself is well known to those skilled in the art and will not be described herein.

The operation of the oscillator 1 according to the invention will now be described in more detail with reference to fig. 1 to 5, and the advantages of the oscillator 1 will be further illustrated.

In operation, the upper body 10 is fixedly connected to the upper drill and the lower coupling 26 of the lower body 20 is fixedly connected to the lower drill. Drilling fluid can flow through the upper tool into the flow channel in the upper body 10 and from there to the first and

second pressure chambers

42, 44 and the underlying fluid oscillation mechanism 50, the inner conduit 61, the lower joint 26 and the lower tool. The drilling fluid flowing into the inner conduit 61 can enter the annular chamber through the upper through hole 611, drive the rotor in the drive turbine assembly 90 to rotate and thereby bring the inner conduit 61 and the rotary valve plate 81 to rotate together.

When the rotary valve plate 81 rotates to the first state, a low-voltage pulse signal is generated. The low pressure pulse signal is transmitted to the first pressure chamber 42 and the second pressure chamber 44 by the oscillation amplifier 50. At this time, the pressures in the first and

second pressure chambers

42 and 44 are less than the pressures in the first and

second balance chambers

41 and 43, or are insufficient to drive the first and

second piston bodies

31 and 33 to move upward. The step surface between the first and

second segments

11 and 12 of the upper body 10 is in contact with the corresponding step surface on the guide housing 21 (the state shown in fig. 1).

When the rotary valve plate 81 rotates to the second state, a high-voltage pulse signal is generated. The high-pressure pulse signal is transmitted to the first pressure chamber 42 and the second pressure chamber 44 via the oscillation amplifier 50. The pressure in the first and

second pressure chambers

42, 44 increases sufficiently to push the first and

second piston bodies

31, 33 upwards and thereby the upper body 10 upwards in relation to the lower body 20. At this time, the upper body 10 is rotated circumferentially with respect to the lower body 20 while moving upward with respect to the lower body 20 by the mutual engagement of the spiral-shaped first guide 111 and the second guide. Therefore, the upper drilling tool can be driven to rotate in the circumferential direction while moving upwards relative to the lower drilling tool.

Thereafter, the rotary valve plate 81 is rotated again to the first state. As it rotates, the pressure in the first and

second pressure chambers

42, 44 decreases. The first piston body 31 and the second piston body 33 are moved downward by the urging of the elastic member 30. The upper body 10 moves downward relative to the lower body 20. At the same time, the upper body 10 is rotated reversely and circumferentially with respect to the lower body 20 by the first guide 111 and the second guide. Accordingly, the upper drilling tool can be driven to move downwards relative to the lower drilling tool, and meanwhile, the upper drilling tool can be driven to rotate circumferentially in the opposite direction.

Repeating the above process can cause the oscillator 1 to move the upper drill and the lower drill together in a relatively complex and violent movement in both the longitudinal and circumferential directions. Therefore, the ratio of the dynamic friction to the static friction between the drilling tool and the well wall can be changed, and the dynamic friction accounts for more. This is very advantageous for reducing frictional resistance during drilling and thus for increasing the drilling speed with lower energy consumption. Therefore, the drilling period can be greatly reduced, and the operation cost can be reduced.

Both the upper drilling tool and the lower drilling tool are here drill strings.

It will be appreciated that depending on the downhole conditions, circumferential rotation of the upper tool relative to the lower tool may be manifested to the borehole wall as circumferential rotation of either the upper tool or the lower tool, or both.

It should also be understood that the directional terms "upper" and "lower" as used herein are relative terms. "up" is the direction near the well head side, and "down" is the direction near the well bottom side. The use of "up" and "down" does not restrict the use of the oscillator 1 of the present invention to vertical well sections.

Likewise, it is also to be understood that reference herein to "longitudinal" is to a direction along the path of the borehole. The path is not limited to a straight direction, and includes an oblique direction and a horizontal direction.

While the invention has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. It is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.

Claims

1. An oscillator connected between an upper drill and a lower drill, the oscillator comprising:

an upper body fixedly connected to the upper drill; and

a lower body fixedly connected to the lower drill;

wherein relative longitudinal movement and relative circumferential rotation can occur between the upper and lower bodies.

2. The oscillator of claim 1, wherein the upper body is at least partially nested within the lower body, wherein a first helical guide is configured on an outer side wall of the upper body, the first helical guide having a longitudinal direction and a circumferential direction component of extension, and a second helical guide that mates with the first helical guide is configured on an inner side wall of the lower body, and wherein relative circumferential rotation between the upper body and the lower body occurs upon relative longitudinal movement between the upper body and the lower body in cooperation with the first helical guide and the second helical guide.

3. The oscillator according to claim 1 or 2, wherein at least one piston body is connected at a lower end of the upper body, the at least one piston body is in sealed sliding engagement with an inner side wall of the lower body, and a fluid oscillating mechanism is provided in the lower body below the at least one piston body, the fluid oscillating mechanism being configured to enable a periodic change in pressure of a fluid passing therethrough, the periodic change in pressure of the fluid being transmittable to below the at least one piston body to push the at least one piston body.

4. The oscillator according to claim 3, characterized in that the at least one piston body comprises a first piston body and a second piston body arranged spaced below the first piston body, the first piston body is directly connected with a lower end of the upper body, a connecting rod extending in a longitudinal direction is arranged between the first piston body and the second piston body, the lower body is configured with a radially inwardly extending bulge spaced apart from the first piston body and the second piston body between the first piston body and the second piston body, the bulge is in sealed sliding fit with the connecting rod, an inner side wall of the lower body, the bulge and the connecting rod surround to form a first pressure chamber below the first piston body, the connecting rod is configured to be hollow, a pressure communication hole communicating with the first pressure chamber is configured on a side wall of the connecting rod, the connecting rod is configured to transmit a pressure of a fluid of the fluid oscillating mechanism into the first pressure chamber, a first balance chamber is formed above the first piston body, a first communication hole communicating the first balance chamber with an external environment is configured on a sidewall of the lower body, a second pressure chamber is formed below the second piston body, the pressure of the fluid oscillating mechanism can be transmitted into the second pressure chamber, a second balance chamber is surrounded by the connecting rod, the boss and an inner sidewall of the lower body above the second piston body, and a second communication hole communicating the second balance chamber with the external environment is configured on the sidewall of the lower body.

5. The oscillator according to claim 3 or 4, wherein the fluid oscillation mechanism comprises:

a fixed valve plate fixedly disposed in the lower body, the fixed valve plate being configured with a fixed flow through hole penetrating the fixed valve plate in a longitudinal direction; and

a rotary valve plate rotatable about a longitudinal axis of the lower body, which rotary valve plate is arranged adjacent to the stationary valve plate on a side of the stationary valve plate facing the at least one piston body, on which rotary valve plate rotary flow through holes are configured which extend through the rotary valve plate in a longitudinal direction;

wherein the fixed flow hole and the rotary flow hole are configured to be eccentrically disposed with respect to a longitudinal axis of the lower body, and an area of a portion where the fixed flow hole and the rotary flow hole overlap periodically changes when the rotary valve plate rotates.

6. The oscillator of claim 5, wherein the fixed flow aperture and the rotating flow aperture have a maximum overlap area in the first state that is equal to the area of the fixed flow aperture and/or the rotating flow aperture; and/or

The stationary flow opening and the rotary flow opening have a minimum overlap area in the second state, the ratio of the minimum overlap area to the area of the stationary flow opening and/or the rotary flow opening being between 0.1 and 0.5, preferably between 0.2 and 0.3.

7. The oscillator of claim 5 or 6, wherein the fluid oscillating mechanism further comprises an inner conduit fixedly connected above the rotary valve plate, the inner conduit being connected to the inner cavity of the upper body and the at least one piston body, and is communicated with the rotary flow through hole on the rotary valve plate, the inner pipeline is sleeved in the lower main body and is spaced from the lower main body, an annular cavity is formed between the inner pipe and the lower body, upper and lower through holes penetrating through a sidewall of the inner pipe are respectively formed at upper and lower ends of the inner pipe, the through holes communicating an inner space of the inner pipe with the annular cavity, a drive turbine assembly is disposed between the upper through hole and the lower through hole in the annular cavity, the drive turbine assembly is configured to rotate the inner conduit in response to fluid flowing therethrough.

8. The oscillator of claim 7, wherein the fluid oscillation mechanism further comprises an oscillator amplifier disposed within the lower body above the inner conduit, the oscillator amplifier configured to amplify and transfer oscillations of the fluid from the inner conduit to the at least one piston body.

9. The oscillator as recited in claim 4, wherein the lower body is configured with a downwardly facing step surface above the first piston body, and a disc spring set is disposed between the step surface and the first piston body.

10. The oscillator according to any one of claims 1 to 9, wherein the upper body includes a first section and a second section extending downward from the first section, an outer diameter of the first section is larger than an outer diameter of the second section, a first abutting surface facing downward is formed at a junction between the first section and the second section, a second abutting surface capable of cooperating with the abutting surface is formed on an inner side of the lower body,

a clamping part is embedded in the outer side wall of the second section of the upper main body, the clamping part radially extends outwards to protrude out of the outer side wall of the second section, a groove for accommodating the clamping part is formed in the inner side wall of the lower main body, the distance between the upper side wall and the lower side wall of the groove is greater than the length of the clamping part,

when the first resisting surface is contacted with the second resisting surface, a gap is formed between the clamping part and the upper side wall of the groove.