A pilot damping structure for winch balance valve of rotary drilling rig

Abstract

The present invention discloses a pilot damping structure of a winch balance valve for a rotary drilling rig, and belongs to the technical field of winch balance valves for rotary drilling rigs. It includes a relief valve I; the control end of the relief valve I is respectively connected to a relief valve II, a damping hole II and a damping hole I; the damping hole I is connected in series with a check valve II, and the series-connected damping hole I and the check valve II are connected in parallel with the damping hole II; the relief valve II is connected in parallel with the damping hole II. The damping hole II and the damping hole I adopt different specifications. When the pressure of the pilot control port of the balance valve fluctuates due to micro-operation, the flow pressure through the damping holes I and the damping holes II of different specifications fluctuates. When the pressure is too large, the relief valve II opens to realize the function of constant pressure fluctuation during frequent opening and closing. When the winch falls, especially under small opening conditions, the present invention can reduce the shaking, improve the reliability of the winch system of the rotary drilling rig, and ensure construction safety.

Description

Technical Field

[0001] The invention relates to a winch balance valve for a rotary drilling rig, in particular to a pilot damping structure of a winch balance valve for a rotary drilling rig. Background Art

[0002] The multifunctional fully hydraulic rotary drilling rig is a mechanical device that repeatedly drills by using drilling tools such as a rotary bucket, a short spiral drill bit, and a long spiral drill bit. This equipment is a high-end hole-forming equipment for large-diameter pile foundation engineering, with the characteristics of high technical content, high concentration of electromechanical and hydraulic, high power of the whole machine, high output torque, high construction efficiency, good success quality, and strong formation adaptability. The main working devices of the rotary drilling rig are the power head and the main winch system, among which the main winch system is used to complete the lifting and lowering of the drill rod and the drill bucket and the floating during the drilling process.

[0003] The winch system is used to realize the functions of load lifting, lowering and load holding. Among them, the load holding function is realized by the core hydraulic component winch balance valve. When the rotary drilling rig completes the winch falling action, due to the existence of the overload, there is often jitter when the winch falls. Generally, the key parameters of the balance valve itself (pilot ratio, spring stiffness, valve core flow area, etc.) are optimized to achieve the matching of the winch balance valve and other components, overcome the jitter phenomenon, and ensure smooth and reliable movement when the winch falls.

[0004] When the winch balance valve is hoisted, it is mainly the one-way valve that works to reduce the loss of oil along the way. When the winch is lowered, it is mainly the overflow valve and the damping hole that work, which is equivalent to adding a load (back pressure) to the oil return port of the winch motor, so that the winch falls smoothly and slowly with little impact. In actual engineering situations, the vibration of the winch mechanism is mainly caused by the mismatch between the flow rate of the oil inlet and the oil return port and the in-and-out time. However, in some cases, due to the aging of the equipment and the contamination of the oil, the steady-state hydraulic stiffness of the actual winch balance valve does not meet the design requirements. Under the coupling with the spring stiffness of the valve core, the vibration range of the natural frequency of the winch balance valve is reached, causing the balance valve valve core to vibrate. At this time, the vibration of the balance valve valve core is no different from the vibration, but the mechanism of formation is completely different.

[0005] The Chinese patent discloses a winch balancing valve (CN212657075U), comprising: a valve body, a balancing valve cavity is arranged in the balancing valve; a valve core, the valve core is inserted in the balancing valve cavity; an A port, the A port is opened on the valve body, the A port is connected to the balancing valve cavity through the first channel, and the A port is connected to the multi-way valve; a B port, the B port is opened on the valve body, the B port is connected to the balancing valve cavity through the second channel, and the B port is a load port; an X port, the X port is opened on the valve body, the X port is connected to the balancing valve cavity through the third channel, the X port is a control port, and a damper is installed in the third channel; wherein, a fourth channel connected to the third channel is also opened on the valve body, and the damper can be replaced through the fourth channel. The damper can be replaced by directly opening the fourth channel without disassembling the hard steel pipe connected to the X port, and the operation is simple.

[0006] The above prior art has the following deficiencies:

[0007] 1. The control port mentioned in the prior art has a simple structure, and its oil drain circuit is only composed of a one-way valve, which does not have the function of adjusting the steady-state fluid dynamic stiffness and is prone to induce resonance when the balance valve is working;

[0008] 2. The balancing valve mentioned in the patent has a non-compact structure and is not advantageous in terms of installation and space occupation.

[0009] 3. The patent uses fixed damping holes for filtering and vibration absorption, which is inconvenient to replace and has poor adaptability. Summary of the invention

[0010] The invention provides a pilot damping structure of a winch balance valve of a rotary drilling rig, which is mainly used to solve the problem that resonance is easily induced when the existing balance valve is working.

[0011] The present invention is achieved through the following technical scheme: a pilot damping structure of a winch balance valve of a rotary drilling rig, comprising a relief valve I; the control end of the relief valve I is respectively connected to a relief valve II, a damping hole II and a damping hole I; the damping hole I is connected in series with a check valve II, and the series-connected damping hole I and the check valve II are connected in parallel with the damping hole II; the relief valve II is connected in parallel with the damping hole II.

[0012] It is further that: the oil inlet of the overflow valve I is connected to the A oil port of the main reversing valve; one end of the overflow valve II is connected to the control end of the overflow valve I, and the other end of the overflow valve II is connected to the B oil port of the main reversing valve; one end of the damping hole II is connected to the control end of the overflow valve I, and the other end of the damping hole II is connected to the B oil port of the main reversing valve; one end of the damping hole I is connected to the control end of the overflow valve I, and the other end of the damping hole I is connected to the one-way valve II, and the other end of the one-way valve II is connected to the B oil port of the main reversing valve; the one-way valve II unidirectionally conducts the hydraulic oil flowing in the direction of the B oil port of the main reversing valve.

[0013] A one-way valve I is connected between the oil inlet and the oil outlet of the relief valve I, and the one-way valve I unidirectionally conducts the hydraulic oil flowing from the oil inlet of the relief valve I to the oil outlet of the relief valve I.

[0014] The oil outlet of the overflow valve I is connected to the winch motor, the other end of the winch motor is connected to a speed regulating valve, and the other end of the speed regulating valve is connected to the B oil port of the main reversing valve; the B oil port of the main reversing valve is connected to the large chamber of the winch brake, and the small chamber of the winch brake is connected to the oil tank.

[0015] The P oil port of the main reversing valve is connected to the hydraulic pump, and the hydraulic pump is connected to the oil tank; the T oil port of the main reversing valve is connected to the oil tank.

[0016] The damping hole II and the damping hole I adopt different specifications.

[0017] The overflow valve II, the damping hole II, the damping hole I and the one-way valve II are integrated on the control end cover of the balancing valve body.

[0018] A safety valve is connected between the oil outlet of the overflow valve I and the oil outlet of the main reversing valve B.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) When the pressure at the pilot control port of the balancing valve fluctuates due to micro-operation, the flow pressure through the damping holes I and II of different specifications fluctuates. When the pressure is too high, the relief valve II opens to achieve the function of constant pressure fluctuation during frequent opening and closing, avoiding resonance and preventing the vibration from interfering with the winch system.

[0021] (2) The structure is simple, the damping network is integrated with the control end cover, the number of assembly parts is small, the cartridge valve structure is adopted, it is easy to produce and assemble, the pressure setting method of the relief valve II is simple and has good adaptability;

[0022] (3) It is highly targeted and suitable for the winch system for the unique working conditions of rotary drilling rigs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is the hydraulic principle diagram of the present invention;

[0024] Figure 2 This is the appearance diagram of the balancing valve;

[0025] In the figure: 1. Oil tank; 2. Hydraulic pump; 3. Main reversing valve; 4. Check valve I; 5. Overflow valve I; 6. Damping hole I; 7. Check valve II; 8. Damping hole II; 9. Overflow valve II; 10. Safety valve; 11. Speed ​​regulating valve; 12. Winch motor; 13. Winch brake; 14. Balance valve body; 15. Control end cover. DETAILED DESCRIPTION

[0026] The following is a specific embodiment of the present invention, and the present invention will be further described in conjunction with the accompanying drawings.

[0027] like Figure 1 and Figure 2 As shown, a pilot damping structure of a winch balance valve of a rotary drilling rig is provided, wherein the oil suction port of the hydraulic pump 2 is connected to the oil tank 1, the oil outlet of the hydraulic pump 2 is connected to the oil port P of the main reversing valve 3, and the oil port T of the main reversing valve 3 is connected to the oil tank 1. The oil port B of the main reversing valve 3 is connected to the large cavity of the winch brake 13, and the small cavity of the winch brake 13 is connected to the oil tank 1.

[0028] The oil inlet of the relief valve I5 is connected to the oil port A of the main reversing valve 3, and the oil outlet of the relief valve I5 is connected to the hoisting motor 12. The other end of the hoisting motor 12 is connected to the speed regulating valve 11, and the other end of the speed regulating valve 11 is connected to the oil port B of the main reversing valve 3. A check valve I4 is connected between the oil inlet and the oil outlet of the relief valve I5. The check valve I4 conducts one-way flow of hydraulic oil from the oil inlet of the relief valve I5 to the oil outlet of the relief valve I5. A safety valve 10 is connected between the oil outlet of the relief valve I5 and the oil port B of the main reversing valve 3.

[0029] The control end of the relief valve Ⅰ5 is connected to the relief valve Ⅱ9, the damping hole Ⅱ8 and the damping hole Ⅰ6 respectively, and the damping hole Ⅱ8 and the damping hole Ⅰ6 adopt different specifications. One end of the damping hole Ⅱ8 is connected to the control end of the relief valve Ⅰ5, and the other end of the damping hole Ⅱ8 is connected to the B oil port of the main reversing valve 3. One end of the damping hole Ⅰ6 is connected to the control end of the relief valve Ⅰ5, and the other end of the damping hole Ⅰ6 is connected to the check valve Ⅱ7, and the other end of the check valve Ⅱ7 is connected to the B oil port of the main reversing valve 3; the check valve Ⅱ7 conducts the hydraulic oil flowing to the B oil port of the main reversing valve 3 in a one-way manner. The relief valve Ⅱ9, the damping hole Ⅱ8 and the series-connected damping hole Ⅰ6 and the check valve Ⅱ7 are connected in parallel. The relief valve Ⅱ9, the damping hole Ⅱ8, the damping hole Ⅰ6 and the check valve Ⅱ7 are integrated on the control end cover 15 of the balancing valve body 14.

[0030] Working principle:

[0031] When the main reversing valve 3 works in the left position, the winch starts to descend. At this time, the control oil applies pressure to the valve core of the relief valve Ⅰ5 through the damping hole Ⅱ8, realizing the slow opening function of the relief valve Ⅰ5;

[0032] When the main reversing valve 3 is switched from the left position to the middle position, the oil is quickly unloaded through the damping hole Ⅰ6 and the one-way valve Ⅱ7, completing the closing of the relief valve Ⅰ5 and locking the pressure;

[0033] When the pressure at the pilot control port of the relief valve Ⅰ5 fluctuates due to micro-operation, the flow pressure through the damping hole Ⅱ8 and the damping hole Ⅰ6 fluctuates. When the pressure is too high, the relief valve Ⅱ9 opens to achieve constant pressure and prevent the vibration from interfering with the winch system.

[0034] The pilot damping structure of the winch balance valve of the rotary drilling rig in this embodiment can adjust and improve the steady-state hydraulic stiffness of the valve port of the winch balance valve, and prevent the resonance caused by the coupling of the steady-state hydraulic stiffness and the spring's own stiffness. When the winch falls, especially under small opening conditions, the vibration is reduced, the reliability of the winch system of the rotary drilling rig is improved, and the construction safety is guaranteed.

Claims

1. A pilot damping structure for a winch balance valve of a rotary drilling rig, characterized in that: The invention comprises an overflow valve I (5); the control end of the overflow valve I (5) is respectively connected to an overflow valve II (9), a damping hole II (8) and a damping hole I (6); the damping hole I (6) is connected in series with a check valve II (7); the series-connected damping hole I (6) and the check valve II (7) are connected in parallel with the damping hole II (8); the overflow valve II (9) is connected in parallel with the damping hole II (8); The oil inlet of the relief valve I (5) is connected to the oil port A of the main reversing valve (3); one end of the relief valve II (9) is connected to the control end of the relief valve I (5), and the other end of the relief valve II (9) is connected to the oil port B of the main reversing valve (3); one end of the damping hole II (8) is connected to the control end of the relief valve I (5), and the other end of the damping hole II (8) is connected to the oil port B of the main reversing valve (3); one end of the damping hole I (6) is connected to the control end of the relief valve I (5), and the other end of the damping hole I (6) is connected to the check valve II (7), and the other end of the check valve II (7) is connected to the oil port B of the main reversing valve (3); the check valve II (7) is unidirectionally conductive to the hydraulic oil flowing in the direction of the oil port B of the main reversing valve (3); A one-way valve I (4) is connected between the oil inlet and the oil outlet of the relief valve I (5), and the one-way valve I (4) unidirectionally conducts the hydraulic oil flowing from the oil inlet of the relief valve I (5) to the oil outlet of the relief valve I (5); The oil outlet of the overflow valve I (5) is connected to the hoisting motor (12), the other end of the hoisting motor (12) is connected to the speed regulating valve (11), the other end of the speed regulating valve (11) is connected to the oil port B of the main reversing valve (3); the oil port B of the main reversing valve (3) is connected to the large chamber of the hoisting brake (13), and the small chamber of the hoisting brake (13) is connected to the oil tank (1); The damping hole II (8) and the damping hole I (6) have different specifications.

2. The pilot damping structure of the winch balance valve of a rotary drilling rig according to claim 1 is characterized in that: The P oil port of the main reversing valve (3) is connected to the hydraulic pump (2), and the hydraulic pump (2) is connected to the oil tank (1); the T oil port of the main reversing valve (3) is connected to the oil tank (1).

3. The pilot damping structure of the winch balance valve of a rotary drilling rig according to claim 1 is characterized in that: The overflow valve II (9), the damping hole II (8), the damping hole I (6) and the check valve II (7) are integrated on the control end cover (15) of the balancing valve body (14).

4. The pilot damping structure of the winch balance valve of a rotary drilling rig according to claim 1 is characterized in that: A safety valve (10) is connected between the oil outlet of the overflow valve I (5) and the oil port B of the main reversing valve (3).

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