Multi-stage hydraulic cylinder for jacking derrick of drilling machine

Abstract

The invention discloses a multi-stage hydraulic cylinder for jacking a derrick of a drilling machine in the technical field of drilling machinery. The multi-stage hydraulic cylinder aims at solving the problem that in the prior art, when a multi-stage hydraulic cylinder stretches out, the stability of a pressing rod is poor. A piston rod is fixedly connected with a bottom plate of a drilling machine through a lug ring, a first cylinder barrel is connected with a derrick, a second cylinder barrel is slidably connected with the drilling machine through a sliding rail structure, and the first cylinder barrel and the second cylinder barrel and the second cylinder barrel and the piston rod telescopically slide along with injection of hydraulic oil in a multi-stage hydraulic cylinder. At the moment, the second cylinder barrel connecting the first cylinder barrel and the piston rod is laterally supported by the drilling machine through a sliding rail structure, the possibility of eccentric fracture is avoided, the stability of the pressing rod is greatly improved, and then the requirement for jacking of a derrick of the drilling machine can be met more safely and stably.

Description

Technical Field

[0001] The invention relates to a multi-stage hydraulic cylinder for jacking up a drilling rig mast, belonging to the technical field of drilling machinery. Background Art

[0002] A long-stroke telescopic hydraulic cylinder is often used in oil drilling rigs and oil workover rigs to jack up the drilling rig mast.

[0003] Hydraulic cylinders typically have a stroke of 15 to 20 meters. Due to the inherent structural limitations of conventional hydraulic cylinders, these long strokes often require oversized designs, which poses significant challenges in manufacturing and transportation. The industry has developed multi-stage nested hydraulic cylinders, which reduce the overall length of the cylinder when retracted and allow for jacking up the drilling rig mast when extended. However, the lack of reliable connections between the nested cylinders in multi-stage hydraulic cylinders results in poor stability of the compression rod when extended.

[0004] Therefore, the existing multi-stage hydraulic cylinder for jacking up the drilling rig mast has the problem of poor stability of the pressure rod when extending. Summary of the Invention

[0005] The purpose of the present application is to overcome the deficiencies in the prior art and to provide a multi-stage hydraulic cylinder with good stability of the pressure rod when extending and lifting the drilling rig mast.

[0006] To achieve the above objectives, this application is implemented using the following technical solutions: The present application provides a multi-stage hydraulic cylinder for jacking up a drilling rig mast, comprising: A first cylinder, a second cylinder and a piston rod, wherein the piston rod is retracted in the second cylinder, and the second cylinder is retracted in the first cylinder; The second cylinder is slidably connected to the drilling rig via a slide rail structure.

[0007] In some embodiments of the present application, a third oil chamber is further opened in the piston rod, and the third oil chamber is connected to the second oil chamber in the second cylinder, and the second oil chamber is connected to the first oil chamber in the first cylinder.

[0008] In some embodiments of the present application, the oil inlet and outlet of the third oil chamber are provided on the rod wall of the piston rod.

[0009] In some embodiments of the present application, the slide rail structure includes a sliding block connected to the second cylinder, and a guide rail is arranged on the drilling rig along the extension and retraction direction of the multi-stage hydraulic cylinder. When the multi-stage hydraulic cylinder is extended and retracted, the sliding block slides on the guide rail.

[0010] In some embodiments of the present application, the sliding block includes an L-shaped sliding block engaged with the guide rail.

[0011] In some embodiments of the present application, the guide rail is an I-beam guide rail, and both sides of one structural surface of the I-beam guide rail are engaged by the L-shaped sliding block.

[0012] In some embodiments of the present application, the sliding block further includes a connecting plate arranged radially along the second cylinder, and both sides of the connecting plate are connected to the L-shaped sliding block via the connecting plate.

[0013] In some embodiments of the present application, an exhaust pressure measuring joint communicating with the first oil chamber is provided on the wall of the first cylinder.

[0014] In some embodiments of the present application, a first piston is provided in the first oil chamber, and a support ring is provided between the first piston and the inner wall of the first cylinder; The bottom wall of the second cylinder close to the first oil chamber is connected to the first piston through a second bolt.

[0015] In some embodiments of the present application, a sealing ring bracket is provided between the inner wall of the first cylinder and the outer wall of the second cylinder, and between the inner wall of the second cylinder and the piston rod wall, and a sealing ring group is embedded in the sealing ring bracket; an annular sealing cover for fixing the position of the sealing ring bracket is also provided at the opening of the first cylinder and the opening of the second cylinder.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The multi-stage hydraulic cylinder provided by the present application is used for lifting the derrick of a drilling rig. The piston rod is fixedly connected to the bottom plate of the drilling rig through an earring, the first cylinder is connected to the derrick, and the second cylinder is slidably connected to the drilling rig through a slide rail structure. As the hydraulic oil in the multi-stage hydraulic cylinder is injected, telescopic sliding occurs between the first cylinder and the second cylinder and between the second cylinder and the piston rod. At this time, the second cylinder connecting the first cylinder and the piston rod obtains lateral support from the drilling rig through the slide rail structure, avoiding the possibility of eccentric breakage, greatly improving the stability of the pressure rod, and thus meeting the lifting requirements of the derrick of the drilling rig more safely and stably. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present application or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1 This is a schematic cross-sectional view of the structure of a multi-stage hydraulic cylinder for jacking up a drilling rig mast provided in this embodiment; Figure 2 yes Figure 1Schematic cross-sectional view of the structure at MM in the middle; Figure 3 Yes Figure 1 Schematic diagram of the sealing structure between the cylinder and the cylinder or between the cylinder and the piston; Figure 4 yes Figure 1 A schematic structural diagram of the first piston; Figure 5 yes Figure 1 A schematic cross-sectional view of the structure showing the extension of the multi-stage hydraulic cylinder; In the picture: 1. First cylinder; 2. Second cylinder; 3. Piston rod; 4. Sliding block; 5. Guide rail; 6. Third oil chamber; 7. Oil inlet and outlet; 8. Exhaust pressure measuring joint; 9. Connecting port; 11. Earring; 12. Ring cover; 13. Sealing ring bracket; 14. Sealing ring assembly; 15. First piston; 16. Second bolt; 17. Support ring. 1.1, first oil chamber; 2.1, second oil chamber; 4.1. L-shaped sliding block; 4.2. Connecting plate; 4.3. First bolt; 5.1. I-beam guide rail. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the present application / the present application's embodiments to clearly and completely describe the technical solutions of the present application / the present application's embodiments. Obviously, the described embodiments are only part of the embodiments of the present application / the present application, and not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present application / the present application, its application, or use. Example 1

[0020] This embodiment provides a multi-stage hydraulic cylinder for jacking up a drilling rig mast, so as to solve the problem of poor stability of the compression rods between the various stages of the hydraulic cylinder when the multi-stage hydraulic cylinder is used to jack up the drilling rig mast in the prior art.

[0021] refer to Figures 1 to 5 , the multi-stage hydraulic cylinder provided in this embodiment includes, A first cylinder 1, a second cylinder 2 and a piston rod 3, wherein the piston rod 3 is retracted in the second cylinder 2, and the second cylinder 2 is retracted in the first cylinder 1; The second cylinder 2 is slidably connected to the drilling rig via a slide rail structure.

[0022] During use, the piston rod 3 is fixedly connected to the bottom plate of the drilling rig through the earring 11, the first cylinder 1 is connected to the derrick, and the second cylinder 2 is slidably connected to the drilling rig through the slide rail structure. As the hydraulic oil in the multi-stage hydraulic cylinder is injected, telescopic sliding occurs between the first cylinder 1 and the second cylinder 2 and between the second cylinder 2 and the piston rod 3. At this time, the second cylinder 2 connecting the first cylinder 1 and the piston rod 3 obtains lateral support from the drilling rig through the slide rail structure, avoiding the possibility of eccentric breakage, greatly improving the stability of the pressure rod, and thus being able to more safely and stably meet the requirements of lifting the drilling rig derrick. Example 2

[0023] This embodiment provides a multi-stage hydraulic cylinder. This embodiment is optimized based on the first embodiment to improve the technical effect and refine the technical solution. For details not fully described in this embodiment, please refer to the first embodiment.

[0024] As one example, refer to Figure 1 and Figure 5 The piston rod 3 also has a third oil chamber 6, which is connected to the second oil chamber 2.1 in the second cylinder 2, and the second oil chamber 2.1 is connected to the first oil chamber 1.1 in the first cylinder 1. Figure 2 and Figure 5 When the hydraulic oil passes through the third oil chamber 6, the piston rod 3 first extends from the second cylinder 2, and then the second cylinder 2 extends relative to the first cylinder 1. The inside-out mode is more stable; and because the third oil chamber 6 is aligned with the axis of the earring 11, it can directly act on the third oil chamber 6, thereby reducing the actual load pressure on the cylinders and piston rod 3 at each level, and improving the stability of the pressure rod.

[0025] As one of the embodiments, the oil inlet and outlet ports 7 of the third oil chamber 6 are arranged on the rod wall of the piston rod 3. The oil inlet and outlet ports 7 are used to control the inflow and outflow of the hydraulic oil of the multi-stage hydraulic cylinder as a whole, so that the oil pressure is transmitted from the end of the piston rod 3 close to the earring 11 to the second oil chamber 2.1 and the first oil chamber 1.1.

[0026] The third oil chamber 6 is formed in the piston rod 3, and the hydraulic oil injection position is set on the side of the piston rod 3, which is conducive to shortening the length of the multi-stage hydraulic cylinder. The third oil chamber 6 forms a plunger structure, reducing the direct pressure exerted by the load on the piston rod 3.

[0027] In one embodiment, the slide rail structure includes a sliding block 4 connected to the second cylinder 2. A guide rail 5 is arranged on the drilling rig along the direction of extension and retraction of the multi-stage hydraulic cylinder. The sliding block 4 slides on the guide rail 5 during the extension and retraction of the multi-stage hydraulic cylinder. Because the outer wall of the second cylinder 2 may be covered by the first cylinder 1, it is suitable to install the sliding block 4 on the end of the second cylinder 2 away from the first cylinder 1. Since the drilling rig has ample space and the guide rails are arranged generally along the extension and retraction direction of the multi-stage hydraulic cylinder, the guide rails 5 are suitable for installation on the drilling rig.

[0028] As one example, refer to Figure 2 The sliding block 4 includes an L-shaped sliding block 4.1 that engages with the guide rail 5 to prevent the slide rail structures from separating from each other.

[0029] As one embodiment, the guide rail 5 is an I-beam guide rail 5.1, and both sides of one structural surface of the I-beam guide rail 5.1 are engaged by L-shaped sliding blocks 4.1.

[0030] As one embodiment, since the second cylinder 2 is spaced a certain distance from the drilling well, refer to Figure 1 、 Figure 2 and Figure 5 The sliding block 4 further includes a connecting plate 4.2 radially arranged along the second cylinder 2, and the two sides of the connecting plate 4.2 are connected to the L-shaped sliding block 4.1 through connecting plates 4.3. Then, the I-beam guide rail 5.1 is engaged by the L-shaped sliding block 4.1 through two symmetrical sides.

[0031] As one example, refer to Figure 1 and Figure 5 The wall of the first cylinder 1 is provided with an exhaust pressure measuring joint 8 connected to the first oil chamber 1.1. The exhaust pressure measuring joint 8 is installed at this position and is farthest from the oil inlet and outlet 7 in terms of connectivity.

[0032] As one example, refer to Figure 1 、 Figure 4 and Figure 5 The piston rod 3 forms a piston structure in the second cylinder 2, while the part of the second cylinder 2 located in the first cylinder 1 does not have a piston structure. Therefore, a first piston 15 is arranged in the first oil chamber 1.1, and a support ring 17 is provided between the first piston 15 and the inner wall of the first cylinder 1. The first piston 15 is used to generate piston thrust. The second cylinder 2 and the piston rod 3 have inertia. The support ring 17 is used to support the outer wall of the second cylinder 2 and the inner wall of the first cylinder 1 to prevent wear and skew between the second cylinder 2 and the first cylinder 1, resulting in oil leakage; and the bottom wall of the second cylinder 2 close to the first oil chamber 1.1 is connected to the first piston 15 by a second bolt 16.

[0033] As one example, refer to Figure 3 A sealing ring bracket 13 is provided between the inner wall of the first cylinder 1 and the outer wall of the second cylinder 2, and between the inner wall of the second cylinder 2 and the rod wall of the piston rod 3. A sealing ring assembly 14 is embedded in the sealing ring bracket 13. An annular sealing cover 12 for fixing the position of the sealing ring bracket 13 is also provided at the opening of the first cylinder 1 and the opening of the second cylinder 2. The annular sealing cover 12 is used to prevent the sealing ring bracket 13 from falling out during the telescopic movement. The sealing ring bracket 13 is used to support and fix the position of the sealing ring assembly 14. Figure 3 As shown, the opening of the first cylinder 1 and the opening of the second cylinder 2 are appropriately expanded to accommodate the sealing ring bracket 13. Figure 3 In the figure, “1 / 2” and “2 / 3” indicate that the figure can be used to represent the sealing schematic between the second cylinder 2 and the piston rod 3, and can also be used to represent the sealing schematic between the first cylinder 1 and the second cylinder 2.

[0034] It is worth noting that when the first cylinder 1 is rigidly connected to the derrick, the second cylinder 2 forms a "moving pair-rotating pair" composite constraint through the engagement of the sliding block 4 with the I-beam guide rail 5.1. The degree of freedom analysis is shown in Table 1 "Degree of Freedom Analysis Table" below: Table 1 Degree of freedom analysis table Constraint Type Allowed movement direction Limiting degrees of freedom Guide rail sliding constraint Axial expansion Limit radial displacement and deflection L-block bite Prevent vertical separation Enhanced torsion resistance It is worth noting that in the traditional structure, the hydraulic oil only acts on the piston end face, causing the piston rod to bear 100% axial pressure. In this embodiment, the hydraulic thrust is directly transmitted to the inner cavity cross-section of the earring 11 through the third oil chamber 6, so that about 30-40% of the load is directly transmitted to the drilling rig base plate through the earring structure, significantly reducing the risk of Euler critical load of the piston rod.

[0035] Hydraulic oil is injected through the inlet and outlet ports 7 on the side wall of the piston rod 3 and pressurized in the order of "third oil chamber 6 → second oil chamber 2.1 → first oil chamber 1.1," resulting in a progressive extension motion. The exhaust pressure gauge 8 in the first oil chamber 1.1 monitors the pressure difference between each stage in real time. For example, when the pressure difference ΔP exceeds a threshold, the safety valve is automatically triggered to prevent asynchrony between stages caused by pressure imbalance in the oil chambers.

[0036] As one example, the seal ring assembly 14 can utilize a triple combination of a primary seal (polyurethane), a guide strip (PTFE), and a dust seal (nylon), which can control the friction coefficient within a range of 0.08-0.12. The seal ring bracket 13 can be mounted in a floating manner, allowing for a certain amount of axial thermal expansion.

[0037] In one embodiment, the connecting plate 4.2 of the sliding block 4 can be made of Q690 high-strength steel. The sealing ring assembly 14 is replaced with hydrogenated nitrile rubber (HNBR) to maintain elastic modulus stability from -50°C to 120°C. The hydraulic oil is replaced with a low-temperature anti-condensation type (pour point < -45°C), and an electric heating zone is added to the third oil chamber 6 to adapt to the Northeast region.

[0038] As one of the embodiments, the inner wall of the first cylinder 1 adopts the "rough honing + fine honing" process, and the cylindricity control is expected to be within 0.02mm; the L-shaped sliding block 4.1 and the connecting plate 4.2 are laser deep penetration welded, and the weld penetration must reach more than 80% of the plate thickness.

[0039] During assembly, a three-level assembly reference system is established: the primary reference uses the mounting surface of the earring 11 of the piston rod 3 as the axial zero point; the secondary reference uses a laser tracker to calibrate the straightness of the guide rail 5 (≤0.1mm / 10m); and the final reference uses a hydraulic test bench to verify that the extension synchronization error of each level is less than 1%.

[0040] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. 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, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0041] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "provided in", "provided with", "located in", "installed", "set", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, or it can be internal communication between two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood based on specific circumstances. "Hinged" includes "rotational connection".

[0042] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A multi-stage hydraulic cylinder for jacking up a drilling rig mast, characterized in that: include, A first cylinder (1), a second cylinder (2) and a piston rod (3), wherein the piston rod (3) is retracted in the second cylinder (2), and the second cylinder (2) is retracted in the first cylinder (1); The second cylinder (2) is slidably connected to the drilling rig via a slide rail structure.

2. The multi-stage hydraulic cylinder for jacking up a drilling rig mast according to claim 1, characterized in that: A third oil chamber (6) is also provided in the piston rod (3), and the third oil chamber (6) is in communication with the second oil chamber (2.1) in the second cylinder barrel (2), and the second oil chamber (2.1) is in communication with the first oil chamber (1.1) in the first cylinder barrel (1).

3. The multi-stage hydraulic cylinder for jacking up the drilling rig mast according to claim 2, characterized in that: The oil inlet and outlet ports (7) of the third oil chamber (6) are provided on the rod wall of the piston rod (3).

4. The multi-stage hydraulic cylinder for jacking up a drilling rig mast according to claim 2, characterized in that: The slide rail structure comprises a sliding block (4) connected to the second cylinder (2); a guide rail (5) is arranged on the drilling rig along the extension and contraction direction of the multi-stage hydraulic cylinder; and the sliding block (4) slides on the guide rail (5) when the multi-stage hydraulic cylinder is extended and contracted.

5. The multi-stage hydraulic cylinder for jacking up the drilling rig mast according to claim 4, characterized in that: The sliding block (4) comprises an L-shaped sliding block (4.1) engaged with the guide rail (5).

6. The multi-stage hydraulic cylinder for jacking up a drilling rig mast according to claim 5, characterized in that: The guide rail (5) is an I-beam guide rail (5.1), and both sides of one structural surface of the I-beam guide rail (5.1) are engaged by the L-shaped sliding block (4.1).

7. The multi-stage hydraulic cylinder for jacking up a drilling rig mast according to claim 6, characterized in that: The sliding block (4) further comprises a connecting plate (4.2) arranged radially along the second cylinder (2), and both sides of the connecting plate (4.2) are connected to the L-shaped sliding block (4.1) via connecting plates (4.3).

8. The multi-stage hydraulic cylinder for jacking up a drilling rig mast according to claim 2, characterized in that: An exhaust pressure measuring joint (8) communicating with the first oil chamber (1.1) is provided on the wall of the first cylinder (1).

9. The multi-stage hydraulic cylinder for jacking up a drilling rig mast according to claim 2, characterized in that: A first piston (15) is provided in the first oil chamber (1.1), and a support ring (17) is provided between the first piston (15) and the inner wall of the first cylinder (1); The bottom wall of the second cylinder (2) close to the first oil chamber (1.1) is connected to the first piston (15) via a second bolt (16).

10. The multi-stage hydraulic cylinder for jacking up a drilling rig mast according to claim 2, characterized in that: A sealing ring bracket (13) is provided between the inner wall of the first cylinder (1) and the outer wall of the second cylinder (2), and between the inner wall of the second cylinder (2) and the rod wall of the piston rod (3), and a sealing ring group (14) is embedded in the sealing ring bracket (13); an annular sealing cover (12) for fixing the position of the sealing ring bracket (13) is also provided at the opening of the first cylinder (1) and the opening of the second cylinder (2).

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