A fluidic throttling pulse generator

Abstract

The present application provides a kind of jet flow throttling pulse generator, comprising: shell;Wall jet element;Split hydraulic cylinder, split hydraulic cylinder includes main cavity, first flow channel and second flow channel respectively communicating main cavity;Impact assembly is arranged in main cavity, impact assembly divides main cavity into upper liquid chamber and lower liquid chamber, first flow channel and second flow channel are communicated with upper liquid chamber and lower liquid chamber respectively;Mounting righting baffle ring in the lower end of split hydraulic cylinder;Overflow valve is arranged below righting baffle ring, overflow valve is equipped with main valve port;Wherein, impact assembly includes piston rod and fixedly sleeved piston on piston rod, the lower end of piston rod extends a part downward, liquid flowing through wall jet element can enter first flow channel and second flow channel in turn alternately, to drive impact assembly reciprocating motion along main cavity with piston, and make the lower end of piston rod alternately insert and exit main valve port, to generate pulse pressure by throttling effect, and impact assembly can form impact to righting baffle ring.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of oil drilling, and particularly relates to a jet type throttling pulse generator. BACKGROUND

[0002] In the drilling of extended reach wells and horizontal wells, because of the large inclination angle, most of the weight of the drill string in the large inclination well section is pressed against the well wall, resulting in large friction between the pipe string and the wellbore, thus increasing the drag pressure and the torque, and further making the weight on bit discontinuous or limited. With the increasing number of extended reach wells and the continuous extension of horizontal displacement, problems such as increased friction and drag pressure and ineffective transmission of weight on bit are faced during drilling, which reduces the mechanical drilling speed of the drilling tool and the horizontal extension capacity, and even cannot drill to the designed well depth. During the drilling operation, it is difficult to send the pipe string into the well only by relying on the weight of the drilling tool in the vertical section, and the tool face is difficult to control, resulting in limited length of the drilled horizontal section and low operation efficiency.

[0003] In the prior art, an oscillator is usually formed by introducing a pressure pulse generating tool and a matched axial vibration generating tool into the downhole pipe string, and a pressure pulse is generated by periodically changing the fluid flow area, which acts on the matched axial vibration generating tool to drive the drilling tool to produce axial creep, reduce the friction coefficient between the pipe string and the well wall during sliding drilling, reduce the friction resistance of the pipe string, eliminate the pipe string drag pressure phenomenon, and improve the weight on bit transmission effect and the directional drilling efficiency.

[0004] The hydraulic oscillator is a special tool for reducing friction and drag, which is usually composed of a pulse generator and a vibration generator. At present, the common pulse generator generally uses a screw or a turbine to drive an eccentric valve disc set to generate hydraulic pressure pulse. The valve disc of the pulse generator with this action principle is prone to erosion, damage and failure, which seriously affects the effect of reducing friction and drag and preventing drag pressure in the later use of the tool. SUMMARY

[0005] In view of the above technical problems, the present application aims to provide a jet type throttling pulse generator which can generate pulse pressure and make the drill string produce axial creep, so as to convert static friction into dynamic friction, which is very beneficial to reduce the friction between the well wall and the drill pipe during sliding drilling and rotary drilling, and can significantly improve the mechanical drilling speed and the horizontal well extension capacity.

[0006] To this end, the application provides a jet throttling pulse generator, comprising: a housing configured in a cylindrical shape; an attached-wall jet element installed in the housing; a split-flow hydraulic cylinder installed at the lower end of the attached-wall jet element, the split-flow hydraulic cylinder being configured to include a main cavity, a first flow channel and a second flow channel respectively communicating with the main cavity; an impact assembly provided in the main cavity, the impact assembly dividing the main cavity into an upper liquid cavity and a lower liquid cavity, the first flow channel and the second flow channel respectively communicating with the upper liquid cavity and the lower liquid cavity; a righting check ring installed at the lower end of the split-flow hydraulic cylinder; and a flow-through valve provided below the righting check ring, the flow-through valve being provided with a main valve port; wherein the impact assembly includes a piston rod and a piston fixedly sleeved on the piston rod, the lower end of the piston rod extending downward by a portion, liquid flowing through the attached-wall jet element being able to enter the first flow channel and the second flow channel alternately in sequence to push the piston to drive the impact assembly to reciprocate along the main cavity, and the lower end of the piston rod being able to alternately insert into and exit from the main valve port, so as to generate pulse pressure through throttling effect and enable the impact assembly to impact the righting check ring.

[0007] In one embodiment, the inlet ends of the first flow channel and the second flow channel are provided on the same axial end surface of the split-flow hydraulic cylinder and respectively communicate with the first liquid outlet and the second liquid outlet of the attached-wall jet element.

[0008] In one embodiment, the first flow channel is configured to extend axially to communicate with the upper space of the main cavity.

[0009] In one embodiment, the second flow channel extends axially to communicate with the lower space of the main cavity,

[0010] The second flow channel is configured to include an inclined passage and a straight passage communicating with the inclined passage, and the straight passage is formed in the side wall of the split-flow hydraulic cylinder.

[0011] In one embodiment, the diameter of the piston rod is configured to be smaller than the inner diameter of the righting check ring and smaller than the diameter of the main valve port, so that liquid can flow through the gaps formed between the piston rod and the righting check ring and between the piston rod and the main valve port.

[0012] In one embodiment, the piston rod is provided with a ring-shaped impact block extending radially outward, the piston is seated on the upper end surface of the ring-shaped impact block, the outer diameter of the ring-shaped impact block is greater than the inner diameter of the righting check ring, and the ring-shaped impact block is able to impact the righting check ring downward.

[0013] In one embodiment, a flow guide cap is provided at the upper end of the attached-wall jet element, the flow guide cap being used to guide liquid to the liquid inlet of the attached-wall jet element.

[0014] In one embodiment, the casing is provided with an upper joint and a lower joint at two ends thereof, the upper joint is used for connecting an upper pipe string, and the lower joint is used for connecting a lower drilling tool, and a gasket is arranged between a lower end surface of the upper joint and an upper end surface of the flow guide cap.

[0015] In one embodiment, an adjusting sleeve is arranged between the centralizing retainer and the flow valve, and upper and lower end surfaces of the flow valve abut against a lower end surface of the adjusting sleeve and an upper end surface of the lower joint, respectively.

[0016] In one embodiment, the centralizing retainer is configured to include a cylindrical body portion and an annular protrusion formed on an outer peripheral surface of the body portion,

[0017] The body portion is inserted into the main cavity, upper and lower end surfaces of the annular protrusion abut against a lower end surface of the hydraulic cylinder and an upper end surface of the adjusting sleeve, respectively, and the centralizing retainer can transmit the impact force generated by the impact assembly to the upper pipe string and the lower drilling tool.

[0018] Compared with the prior art, the application has the following advantages:

[0019] The jet flow throttling pulse generator according to the application can generate pulse pressure and can make the drill string produce axial peristalsis, so as to convert static friction into dynamic friction, which is very beneficial to reduce the friction between the well wall and the drill pipe during sliding drilling and rotary drilling, significantly improves the WOB transmission, improves the directional efficiency, and can significantly improve the ROP and the horizontal well extension capacity, greatly improves the drilling efficiency and the drilling operation effect. The jet flow throttling pulse generator periodically blocks the flow passage by the up-down movement of the piston rod to generate pulse pressure, and the pulse pressure generated by the jet flow throttling pulse generator is superimposed with the pulse pressure generated by the wall-attached jet flow element itself, so that the pulse pressure generated by the jet flow throttling pulse generator has a larger amplitude. Compared with the common pulse generator for generating hydraulic pulse by using a screw and a turbine driven eccentric valve disc group, the jet flow pulse generator can significantly improve the generated pulse pressure and has good anti-erosion performance. BRIEF DESCRIPTION OF DRAWINGS

[0020] The application will be described below with reference to the drawings.

[0021] Figure 1 The structure of the jet flow throttling pulse generator according to the application is shown.

[0022] Figure 2 The structure of the jet flow throttling pulse generator according to the application is shown. Figure 1 The impact assembly in the jet flow throttling pulse generator shown is shown in a state of descending and impacting the centralizing retainer 5.

[0023] In the present application, all the drawings are schematic drawings for illustrating the principles of the present application only and are not drawn to scale. DETAILED DESCRIPTION

[0024] The present application will be described below with reference to the drawings.

[0025] In the present application, it is to be noted that the lower end of the jet throttle pulse generator according to the present application lowered into the wellbore near the wellhead is defined as the upper end or similar terms, and the end away from the wellhead is defined as the lower end or similar terms. In addition, it is to be noted that the directional terms or limiting terms "upper", "lower" and the like used in the present application are all with respect to the drawings referred to. They are not used to define the absolute position of the parts involved, but can be changed according to the specific situation. Figure 1

[0026] Figure 1 The structure of the jet throttle pulse generator 100 according to the present application is shown. In actual application, the jet throttle pulse generator 100 is connected in the drilling pipe string, the upper end of the jet throttle pulse generator 100 is connected to a vibration generating tool (not shown) through the pipe string, and the lower end is connected to the drill pipe or the lower drilling tool (not shown).

[0027] As shown in Figure 1 , the jet throttle pulse generator 100 comprises a shell 1 configured in a cylindrical shape, an attached-wall jet element 2 installed in the interior of the shell 1, a shunt hydraulic cylinder 3, an impact assembly 4 arranged in the interior of the shunt hydraulic cylinder 3, a centralizing retainer 5 arranged at the lower end of the shunt hydraulic cylinder 3, and a flow valve 6 arranged below the centralizing retainer 5. In operation, the liquid flowing through the attached-wall jet element 2 of the jet throttle pulse generator 100 can drive the impact assembly 4 to reciprocate, and can cause the opening size of the main valve port 61 of the flow valve 6 to change to form throttling, thereby generating pulse pressure, at the same time, the impact assembly 4 can form impact on the centralizing retainer 5, and further transmit to the drill string and other drilling tools connected with the jet throttle pulse generator 100. Thus, the jet throttle pulse generator 100 can cause the drill string to produce axial peristalsis, thereby converting static friction into dynamic friction, which is very beneficial to reduce the friction between the well wall and the drill pipe during sliding drilling and rotary drilling, can significantly improve the rate of penetration and the horizontal well extension capacity, greatly improve the drilling efficiency and drilling operation effect. In addition, the pulse generated by the jet throttle pulse generator 100 can act on the vibration generating tool connected to the upper end of the jet throttle pulse generator 100, drive the vibration generating tool to produce vibration, further reduce friction and resistance.

[0028] As shown in Figure 1 ​As shown, the upper and lower ends of the housing 1 are fixedly connected with an upper joint 7 and a lower joint 8 respectively, the upper joint 7 is used to connect the upper pipe column, and the lower joint 8 is used to connect the lower drilling tool. In an embodiment, the upper joint 7 and the lower joint 8 are fixedly connected with the housing 1 through threaded connection.

[0029] In Figure 1 In the embodiment shown, the two ends of the housing 1 are configured as negative taper connection buckles, the lower end of the upper joint 7 is configured as a positive taper connection buckle, and the upper joint 7 is fixedly connected with the upper end of the housing 1 through the adaptation of the positive taper connection buckle and the negative taper connection buckle. The upper end of the upper joint 7 is fixedly connected with the upper pipe column through the adaptation of the negative taper connection buckle. Similarly, the two ends of the lower joint 8 are configured as positive taper connection buckles, and the lower joint 8 is fixedly connected with the lower end of the housing 1 through the adaptation of the positive taper connection buckle and the negative taper connection buckle. The lower end of the lower joint 8 is fixedly connected with the lower drilling tool through the adaptation of the positive taper connection buckle. This connection structure of the upper joint 7 and the lower joint 8 is very beneficial to ensure the connection stability between the housing 1 and the upper pipe column and the lower drilling tool, and is convenient and fast to install.

[0030] In the embodiment, the lower end of the upper joint 7 is inserted into the housing 1, so that the lower end face of the upper joint 7 forms a first step with the end face downward at the inner wall position close to the upper end of the housing 1. Similarly, the upper end of the lower joint 8 is inserted into the housing 1, so that the upper end face of the lower joint 8 forms a second step with the end face upward at the inner wall position close to the lower end of the housing 1. The functions of the first step and the second step will be introduced below.

[0031] As Figure 1 As shown, a flow guide cap 20 is arranged at the upper end of the wall-attached jet element 2, and the flow guide cap 20 is used to guide the liquid to the liquid inlet 21 of the wall-attached jet element 2. The inside of the flow guide cap 20 is provided with a stepped hole, and the large-diameter end of the stepped hole is upward and communicates with the upper joint 7, and the small-diameter end of the stepped hole is downward and communicates with the liquid inlet 21 of the wall-attached jet element 2. The upper and lower end faces of the flow guide cap 20 abut against the first step and the upper end face of the wall-attached jet element 2 respectively, so as to form axial limitation. This structure of the flow guide cap 20 is very beneficial to guide the liquid from the upper pipe column into the wall-attached jet element 2.

[0032] In an embodiment, a gasket 9 can be installed between the lower end face (first step) of the upper joint 7 and the upper end face of the flow guide cap 20. The gasket 9 can be used as an adjusting piece during installation, which is convenient to install. At the same time, the gasket 9 is also beneficial to ensure the sealing between the upper joint 7 and the housing 1.

[0033] According to the present application, the shunt hydraulic cylinder 3 is installed at the lower end of the wall-attached jet element 2, and the upper end face of the shunt hydraulic cylinder 3 is closely combined with the lower end face of the wall-attached jet element 2.

[0034] AsFigure 1 As shown, the shunt hydraulic cylinder 3 is configured in a cylindrical shape, and a main cavity 31, a first flow channel 32 and a second flow channel 33 are arranged inside the shunt hydraulic cylinder 3, and the first flow channel 32 and the second flow channel 33 are respectively communicated with the main cavity 31. The inlet ends of the first flow channel 32 and the second flow channel 33 are arranged on the same axial end surface (the upper end surface in the figure) of the shunt hydraulic cylinder 3, and the inlet end of the first flow channel 32 is communicated with the first liquid outlet 22 of the wall-attached jet element 2. The inlet end of the second flow channel 33 is communicated with the second liquid outlet 23 of the wall-attached jet element 2. Preferably, the inlet ends of the first flow channel 32 and the second flow channel 33 can be arranged to be distributed in opposite radial directions. Figure 1

[0035] The first flow channel 32 is configured to extend axially to communicate with the upper space of the main cavity 31.

[0036] The second flow channel 33 extends axially to communicate with the lower space of the main cavity 31. The second flow channel 33 is configured to include an inclined passage 331 and a straight passage 332 communicated with the inclined passage 331, and the straight passage 332 is formed in the side wall of the shunt hydraulic cylinder 3.

[0037] According to the present application, the impact assembly 4 is arranged in the main cavity 31 of the shunt hydraulic cylinder 3, and the main cavity 31 is divided into an upper liquid cavity 311 and a lower liquid cavity 312. The first flow channel 32 is communicated with the upper liquid cavity 311, and the second flow channel 33 is communicated with the lower liquid cavity 312. The liquid from the upper drill string flows through the wall-attached jet element 2, and is alternately introduced into the first flow channel 32 and the second flow channel 33 under the action of the wall-attached jet element 2, and then is alternately introduced into the upper liquid cavity 311 and the lower liquid cavity 312, so that the impact assembly 4 reciprocates under the action of the liquid pressure.

[0038] According to the present application, the impact assembly 4 includes a piston rod 41 and a piston 42 fixedly sleeved on the piston rod 41, and the piston 42 forms a sliding seal with the side wall of the main cavity 31. The length of the piston rod 41 at the lower end portion of the piston 42 is greater than the length of the piston rod 41 at the upper end portion of the piston 42, and the lower end of the piston rod 41 extends downward through the centralizing baffle 5. The flow-through valve 6 arranged below the centralizing baffle 5 is provided with a main valve port 61, and the lower end of the piston rod 41 can extend downward to correspond to the main valve port 61. Thus, the upper liquid cavity 311 is formed above the upper end surface of the piston 42, and the lower liquid cavity 312 is formed below the piston 42. When the liquid enters the upper liquid cavity 311 through the first flow channel 32, the liquid pressure acts on the upper end surface of the piston 42 to push the piston 42 to move downward. When the liquid enters the lower liquid cavity 312 through the second flow channel 33, the liquid pressure acts on the lower end surface of the piston 42 to push the piston 42 to move upward.

[0039] ​In one embodiment, the piston rod 41 is provided with a radially outwardly extending annular impact block 43, and the piston 42 sits on the upper end face of the annular impact block. The outer diameter of the annular impact block 43 is larger than the inner diameter of the centralizing ring 5, thereby allowing the impact assembly 4 to move downward so that the annular impact block 43 impacts the centralizing ring 5. The diameter of the piston rod 41 is set to be smaller than the inner diameter of the centralizing ring 5 and smaller than the diameter of the main valve port 61 of the overflow valve 6, so that liquid can flow through the gaps formed between the piston rod 41 and the centralizing ring 5, and between the piston rod 41 and the main valve port 61.

[0040] Therefore, under the action of liquid pressure, piston 42 can drive piston rod 41 to reciprocate along the main cavity 31. During the reciprocating motion, on the one hand, the lower end of piston rod 41 alternately inserts into and exits the main valve port 61 of the overflow valve 6, so that the opening size of the main valve port 61 changes to form throttling, thereby generating pulse pressure through throttling. On the other hand, piston rod 41 impacts the centering retainer ring 5 through the annular impact block 43, thereby transmitting the generated pulse pressure and impact force to the drill string and other drill tools connected to the jet-type throttling pulse generator 100.

[0041] In one embodiment, to prevent the overflow valve 6 from becoming blocked, the overflow valve 6 is further provided with an overflow valve port 62. The overflow valve port 62 is located radially outside the main valve port 61.

[0042] According to the present invention, the impact stroke of the impact assembly 4 depends on the axial movement range of the impact assembly 4 within the main cavity 31, and the impact stroke H of the impact assembly 4 is:

[0043] H = L1 - L2

[0044] Wherein, L1 is the axial length of the main cavity 31, and L2 is the distance between the upper end face of the piston rod 41 and the lower end face of the annular impact block 43. The pulse amplitude and pulse frequency generated by the jet-type throttling pulse generator 100 can be adjusted by adjusting the impact stroke of the impact assembly 4. This impact stroke of the impact assembly 4 ensures that the amplitude of the pulse pressure generated by the jet-type throttling pulse generator 100 meets the requirements.

[0045] like Figure 1 As shown, the centering retaining ring 5 is fixedly installed at the lower end of the hydraulic cylinder 3. An adjusting sleeve 10 is installed between the flow valve 6 and the centering retaining ring 5, with the upper and lower end faces of the adjusting sleeve 10 abutting against the lower end face of the centering retaining ring 5 and the upper end face of the flow valve 6, respectively. Simultaneously, the lower end of the flow valve 6 rests on the upper end face (second step) of the lower connector 8. Therefore, the adjusting sleeve 10 provides limiting support for the centering retaining ring 5, thereby fixing the centering retaining ring 5 to the lower end of the hydraulic cylinder 3. Furthermore, the adjusting sleeve 10 serves as an adjustment component during installation, facilitating installation.

[0046] According to one embodiment of the present application, the righting check ring 5 is configured to include a cylindrical body portion 51 and an annular protrusion 52 formed on the outer circumferential surface of the body portion 51. The lower end of the flow fluid cylinder 3 is configured to be open. The body portion 51 of the righting check ring 5 is inserted from the lower end opening of the flow fluid cylinder 3 and forms a seal with the flow fluid cylinder 3, thereby forming the main cavity 31 between the flow fluid cylinder 3 and the righting check ring 5. The upper and lower end faces of the annular protrusion 52 of the righting check ring 5 abut against the lower end face of the flow fluid cylinder 3 and the upper end face of the adjusting sleeve 10, respectively, so that the righting check ring 5 is fixedly installed between the flow fluid cylinder 3 and the adjusting sleeve 10. The righting check ring 5 can transmit the pressure pulse and impact force generated by the impact assembly 4 to the upper pipe column and the lower drilling tool connected with the jet flow throttling pulse generator 100 in sequence through the annular protrusion 52, the adjusting sleeve 10, and the lower joint 8.

[0047] The working process of the jet flow throttling pulse generator 100 according to the present application is briefly described below. In the actual working process, the liquid from the upper drilling column flows through the wall-attached jet element 2, and under the action of the wall-attached jet element 2, the liquid alternately enters the first flow channel 32 and the second flow channel 33, and then alternately enters the upper liquid cavity 311 and the lower liquid cavity 312. The liquid pressure generated by the liquid entering the upper liquid cavity 311 and the lower liquid cavity 312 acts on the upper end face and the lower end face of the piston 42, respectively, thereby driving the piston 42 to drive the impact assembly 4 to reciprocate under the action of the liquid pressure. Figure 1 and Figure 2 The reciprocating process of the impact assembly 4 is shown, Figure 1 The state of the impact assembly 4 ascending to the high point is shown, Figure 2The impact assembly 4 is shown in the state of descending to impact the righting check ring 5. During the reciprocating motion of the impact assembly 4, on the one hand, the lower end of the piston rod 41 is alternately inserted into and withdrawn from the main valve port 61 of the overflow valve 6 to change the opening size of the main valve port 61 to form throttling, so that the pulse pressure is generated by the throttling effect, and on the other hand, the piston rod 41 generates periodic impact on the righting check ring 5 through the annular impact block 43, and the generated pulse pressure and impact force can be transmitted to the drill string and other drilling tools connected with the jet flow throttling pulse generator 100 through the righting check ring 5, the adjusting sleeve 10 and the lower joint 8 in sequence, so that the drill string generates axial peristalsis, thereby converting static friction into dynamic friction, so as to realize friction reduction and drag reduction. In this process, the wall-attached jet flow element 2 itself also generates pressure pulses, which realize pressure transformation through the left-right conversion flow channel. Thus, the jet flow throttling pulse generator 100 periodically blocks the overflow passage by the up-down motion of the piston rod 41 to generate pulse pressure, and the pulse pressure generated by the jet flow throttling pulse generator 100 is superimposed with the pulse pressure generated by the wall-attached jet flow element 2 itself, so that the pulse pressure generated by the jet flow throttling pulse generator 100 has a larger amplitude. In addition, the pulse generated by the jet flow throttling pulse generator 100 can act on the vibration generating tool connected to the upper end of the jet flow throttling pulse generator 100 to drive the vibration generating tool to generate vibration, thereby realizing further friction reduction and drag reduction.

[0048] The jet flow throttling pulse generator 100 according to the present application can generate pulse pressure and can make the drill string generate axial peristalsis, thereby converting static friction into dynamic friction, which is very beneficial to reduce the friction between the well wall and the drill pipe during sliding drilling and rotary drilling, significantly improves the weight on bit transmission, improves the directional efficiency, and can significantly improve the rate of penetration and the horizontal well extension capacity, greatly improves the drilling efficiency and the drilling operation effect. The jet flow throttling pulse generator 100 periodically blocks the overflow passage by the up-down motion of the piston rod 41 to generate pulse pressure, and the pulse pressure generated by the jet flow throttling pulse generator 100 is superimposed with the pulse pressure generated by the wall-attached jet flow element 2 itself, so that the pulse pressure generated by the jet flow throttling pulse generator 100 has a larger amplitude. Compared with the common pulse generator which generates hydraulic pulse by using a screw or a turbine driven eccentric valve disc group, the jet flow pulse generator 100 can significantly improve the pulse pressure generated thereby, and has good anti-erosion performance.

[0049] In the description of the present application, the terms "first", "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0050] In this application, unless otherwise clearly indicated and limited, the terms "mounting", "connection", "connecting", "fixed", and the like should be understood broadly, for example, can be fixed connection, can also be detachable connection, or integrally connected; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0051] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0052] Finally, it should be pointed out that the above description is only the preferred embodiment of the present application and does not constitute any limitation on the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments or replace some technical features with equivalent ones. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A jet throttling pulse generator, comprising: a housing (1) configured in a cylindrical shape; a wall-attached jet element (2) installed in the housing; a shunt hydraulic cylinder (3) installed at a lower end of the wall-attached jet element, the shunt hydraulic cylinder being configured to include a main cavity (31), a first flow passage (32) and a second flow passage (33) respectively communicating with the main cavity; a striking assembly (4) provided in the main cavity, the striking assembly dividing the main cavity into an upper liquid cavity (311) and a lower liquid cavity (312), the first flow passage and the second flow passage respectively communicating with the upper liquid cavity and the lower liquid cavity; a centralizing retainer (5) installed at a lower end of the shunt hydraulic cylinder; and a flow-through valve (6) provided below the centralizing retainer, the flow-through valve being provided with a main valve port (61); wherein the striking assembly includes a piston rod (41), a piston (42) fixedly sleeved on the piston rod, and an annular striking block (43) extending radially outward on the piston rod, the piston being seated on an upper end face of the annular striking block, a lower end of the piston rod extending downward by a portion, liquid flowing through the wall-attached jet element being able to enter the first flow passage and the second flow passage alternately in sequence to push the piston to drive the striking assembly to reciprocate along the main cavity, and the lower end of the piston rod being able to alternately insert into and exit from the main valve port, so as to generate pulse pressure through throttling effect and enable the striking assembly to strike the centralizing retainer, an outer diameter of the annular striking block being greater than an inner diameter of the centralizing retainer, and the annular striking block being able to strike the centralizing retainer.

2. The fluidic throttling pulse generator of claim 1, wherein, Inlet ends of the first flow passage and the second flow passage are provided on a same axial end face of the shunt hydraulic cylinder and respectively communicate with a first liquid outlet (22) and a second liquid outlet (23) of the wall-attached jet element.

3. The fluidic throttling pulse generator of claim 2, wherein, The first flow passage is configured to extend axially to communicate with an upper space of the main cavity.

4. The fluidic throttling pulse generator according to claim 2 or 3, characterized in that The second flow passage extends axially to communicate with a lower space of the main cavity. The second flow passage is configured to include an inclined passage (331) and a straight passage (332) communicating with the inclined passage, and the straight passage is formed in a side wall of the shunt hydraulic cylinder.

5. The fluidic throttling pulse generator according to any one of claims 1 to 3, characterized in that A diameter of the piston rod is configured to be smaller than the inner diameter of the centralizing retainer and smaller than a diameter of the main valve port, so that liquid is able to flow through gaps formed between the piston rod and the centralizing retainer and between the piston rod and the main valve port.

6. The fluidic throttling pulse generator according to any one of claims 1 to 3, characterized in that A flow guide cap (20) is provided at an upper end of the wall-attached jet element, the flow guide cap being used to guide liquid to a liquid inlet (21) of the wall-attached jet element.

7. The fluidic throttling pulse generator of claim 6, wherein, Upper and lower joints (7, 8) are respectively provided at two ends of the housing, the upper joint being used to connect an upper pipe string, and the lower joint being used to connect a lower drilling tool, a gasket (9) being installed between a lower end face of the upper joint and an upper end face of the flow guide cap.

8. The fluidic throttling pulse generator of claim 7, wherein, An adjusting sleeve (10) is installed between the centralizing retainer and the flow-through valve, and upper and lower end faces of the flow-through valve respectively abut against a lower end face of the adjusting sleeve and an upper end face of the lower joint.

9. The fluidic throttling pulse generator of claim 8, wherein, The righting check ring is configured to include a cylindrical body part (51) and an annular protrusion (52) formed on the outer peripheral surface of the body part, The body part is inserted into the main cavity, the upper and lower end faces of the annular protrusion respectively abut against the lower end face of the shunt hydraulic cylinder and the upper end face of the adjusting sleeve, and the righting check ring can transmit the impact force generated by the impact assembly to the upper pipe column and the lower drilling tool.

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