A damper and a support system for an offshore platform including the damper

Abstract

This invention discloses a damper and a support system for an offshore platform including the damper, relating to the field of damper design technology. It includes a cylinder, a piston rod, a piston, and a guide wheel connected to one end of the piston rod. The guide wheel contacts and supports the flange surface of the offshore platform. The piston divides the cylinder into a first chamber and a second chamber, both filled with a damping medium. A return spring is provided in the first chamber. A radial clearance exists between the piston and the cylinder. In a free state, the piston rod extends towards the guide wheel under the action of the return spring. A one-way valve is provided inside the piston. When the piston moves towards the first chamber, the one-way valve closes; when the piston moves towards the second chamber, the one-way valve opens. This invention can withstand a large damping force in the initial stage of stress, reducing deformation of the offshore platform. Furthermore, after the impact force disappears, the piston rod can quickly return to its original position, immediately supporting the offshore platform.

Description

Technical Field

[0001] This invention relates to the field of damper design technology, and more particularly to a damper and a support system for offshore platforms including the damper. Background Technology

[0002] In traditional structures, the upper part of the offshore platform is suspended and the bottom is supported laterally by a support platform. When the support platform is sailing or deforms during offshore operations, the kinetic energy or deformation can be easily transmitted to the offshore platform, causing it to sway and affecting the equipment inside. Therefore, a damper needs to be installed between the offshore platform and the support platform to reduce the impact of the deformation or movement of the support platform on the offshore platform. However, traditional dampers often generate damping force at the end of the piston rod movement and have a relatively slow reset speed, which cannot prevent the offshore platform from being subjected to force.

[0003] Furthermore, traditional dampers often use orifice damping. When orifice dampers work for a long time, the cleanliness of the oil inside the cylinder may be a problem, which can cause the orifice to become clogged. This causes the cylinder to become rigid instantly and unable to provide damping force. Moreover, when the cylinder is subjected to continuous external force, the piston needs to continuously dampen. The oil under the orifice is compressed and buffered, which can easily generate high temperature and high pressure. Since the piston of the orifice damper needs to be sealed, the high temperature and high pressure put too much burden on the piston's main seal, which can cause premature damage or breakage of the seal. Once the main seal is damaged, the cylinder will be unable to provide damping force. Summary of the Invention

[0004] In order to solve the technical problem that the existing technology of dampers cannot avoid the stress on the offshore platform when used to support the offshore platform, and still affects the internal equipment of the offshore platform, the present invention provides a damper and an offshore platform support system including the damper to solve the above problems.

[0005] This invention proposes a damper, comprising a cylinder, a piston rod, a piston, and a guide wheel connected to one end of the piston rod. The guide wheel is in contact with and supported by the flange surface of an offshore platform. The piston divides the cylinder into a first chamber and a second chamber, both filled with a damping medium. A return spring is provided in the first chamber. A radial clearance exists between the piston and the cylinder. In a free state, the piston rod extends towards the guide wheel under the action of the return spring. A one-way valve is provided inside the piston. When the piston moves towards the first chamber, the one-way valve closes; when the piston moves towards the second chamber, the one-way valve opens.

[0006] In an optional embodiment of the present invention, the end of the piston rod is further provided with a guide wedge located above the guide wheel, and the guide wedge contacts and guides the flange surface of the offshore platform.

[0007] In an optional embodiment of the present invention, the one-way valve includes a flow hole penetrating both ends of the piston, and a ball, an elastic element, and a retaining ring located within the flow hole. The end of the flow hole facing the second cavity is a small diameter section with a diameter smaller than that of the ball. The retaining ring is located at the other end of the flow hole, and the elastic element abuts against the retaining ring and the ball. In its natural state, the ball abuts against the end of the small diameter section to block the flow hole.

[0008] In an optional embodiment of the present invention, both ends of the piston rod extend out of the cylinder.

[0009] In an optional embodiment of the present invention, a support seat is provided on the outer surface of the cylinder, and the guide wedge is slidably engaged with the support seat.

[0010] In an optional embodiment of the present invention, the bottom of the cylinder is provided with a base, and the base is provided with mounting holes for fixing to the support platform.

[0011] In an optional embodiment of the present invention, the cylinder includes a cylinder body and guide sleeves located at both ends of the cylinder body. The guide sleeves are in sealing contact with the piston rod. Between the contact surfaces of the guide sleeves and the piston rod, a dustproof ring, a first U-ring, a second U-ring, a support belt, and a Glyd ring are arranged axially from the outside to the inside of the cylinder body. The dustproof ring is made of PTFE material, and the first U-ring and the second U-ring are made of HPU material. The first U-ring is installed outward, and the second U-ring is installed inward.

[0012] In an optional embodiment of the present invention, the angle between the guide wedge and the vertical direction is 8° to 10°.

[0013] The present invention also proposes an offshore platform support system, comprising an offshore platform, a support platform, and a plurality of dampers as described above, wherein the dampers are evenly arranged on the outer periphery of the offshore platform, and the cylinder of the damper is fixed to the support platform.

[0014] The beneficial effects of this invention are:

[0015] (1) The damper of the present invention is filled with a fixed volume of damping medium in the cylinder. When the piston rod is subjected to the pressure of the offshore platform, the damping medium can only flow to the second cavity through the radial gap between the piston and the cylinder due to the one-way valve being closed. The damping force is large and the piston rod moves slowly, so that it can be subjected to a large damping force in the early stage of the force, reducing the deformation of the offshore platform. After the impact force disappears, the piston rod moves in the opposite direction. Due to the one-way valve being open, the piston rod can quickly reset and immediately support the offshore platform.

[0016] (2) The damper described in this invention adopts a gap damping design, which can avoid oil blockage and the risk of oil leakage.

[0017] (3) The present invention provides multiple seals between the piston rod and the guide sleeve, which has waterproof and pressure-resistant effects, effectively prevents leakage, and avoids planktonic organisms from adhering to the surface of the piston rod. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0019] Figure 1 This is a perspective view of a specific embodiment of the damper described in this invention;

[0020] Figure 2 This is a top view of a specific embodiment of the damper described in this invention;

[0021] Figure 3 yes Figure 2 Sectional view along axis AA;

[0022] Figure 4 yes Figure 3 Enlarged view of point a in the middle;

[0023] Figure 5 yes Figure 3 Enlarged view at point b;

[0024] Figure 6 This is a front view of the offshore platform support system described in this invention;

[0025] Figure 7 This is a schematic diagram showing the positional relationship between the damper and the offshore platform in the offshore platform support system described in this invention (only a partial structure is shown).

[0026] In the diagram, 1. Damper, 2. Cylinder, 201. Cylinder body, 202. Guide sleeve, 3. Piston rod, 4. Piston, 5. Guide wheel, 6. Offshore platform, 7. First cavity, 8. Second cavity, 9. Return spring, 10. Radial clearance, 11. One-way valve, 1101. Flow hole, 1102. Ball bearing, 1103. Elastic element, 1104. Retaining ring, 12. Flange, 13. Support platform, 14. First damper, 15. Second damper, 16. Small diameter section, 17. Base, 18. Glyd ring, 19. Mounting hole, 20. Guide wedge, 22. Dustproof ring, 23. First U-ring, 24. Second U-ring, 25. Support belt. Detailed Implementation

[0027] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0028] Example 1

[0029] like Figures 1-3 As shown, a damper includes a cylinder 2, a piston rod 3, a piston 4, and a guide wheel 5 connected to one end of the piston rod 3. The guide wheel 5 is in contact with and supported by the flange surface of the offshore platform 6. The piston 4 divides the cylinder 2 into a first cavity 7 and a second cavity 8. The first cavity 7 and the second cavity 8 are filled with a damping medium. A return spring 9 is provided in the first cavity 7. There is a radial clearance 10 between the piston 4 and the cylinder 2. In the free state, the piston rod 3 extends towards the guide wheel 5 under the action of the return spring 9. A one-way valve 11 is provided in the piston 4. When the piston 4 moves towards the first cavity 7, the one-way valve 11 is closed. When the piston 4 moves towards the second cavity 8, the one-way valve 11 is opened.

[0030] When piston 4 moves from equilibrium towards the first chamber 7 under the action of external force, the damping medium can only flow from the first chamber 7 to the second chamber 8 through the radial gap 10 between piston 4 and cylinder 2 due to the closed one-way valve 11. The flow speed is slow, the damping force is large, the volume of the second chamber 8 increases slowly, and the piston rod 3 retracts slowly. Conversely, when piston 4 moves towards the second chamber 8 (mainly retracted under the action of return spring 9), the damping medium can flow from the second chamber 8 to the first chamber 7 through both the radial gap 10 and the one-way valve 11 due to the open one-way valve 11. Compared to the retraction of piston rod 3, the volume of the first chamber 7 increases faster at this time, and piston rod 3 retracts and extends at a faster speed.

[0031] The application of the damper 1 described in this invention in a support system is as follows: Figure 6 As shown, the offshore platform 6 is suspended at its upper end, with a flange 12 at its bottom. The side of the flange 12 is beveled. The damper 1 is fixed to the support platform 13. When the damper 1 supports the offshore platform 6, the guide wheel 5 abuts against the side of the flange 12. Multiple dampers 1 are evenly arranged around the outer perimeter of the offshore platform 6. In this embodiment, four dampers 1 are provided outside the offshore platform 6. Figure 7 The diagram shows two dampers 1 arranged opposite each other outside the offshore platform 6.

[0032] Combination Figure 7 Describe the buffering principle of damper 1 on offshore platform 6: Assume that the supporting platform 13 is subjected to... Figure 7An impact in the F direction causes changes in the first damper 14 and the second damper 15, which are parallel to the F direction. The first damper 14, compressed by the offshore platform 6, retracts its piston rod 3. During this retraction, the damping force is significant, gradually eliminating the impact force on the supporting platform 13 and reducing the impact on the offshore platform 6. Simultaneously, the second damper 15, under the influence of impact inertia, opens the one-way valve 11, and its piston rod 3 extends outward. Both the first and second dampers 14 remain supported on the outside of the offshore platform 6. After the impact, the first damper 14 quickly resets under the action of the internal return spring 9 and the one-way valve 11, while the second damper 15 gradually resets after the inertial force disappears to achieve pressure balance between the two chambers. Throughout the process, due to the large damping force of the damper 1 and the small extension / retraction range of the support rod, the bottom of the offshore platform 6 experiences minimal lateral movement, thus minimizing impact on internal equipment.

[0033] The one-way valve 11 may, but is not limited to, adopt the following structure:

[0034] like Figure 4 As shown, the one-way valve 11 includes a flow hole 1101 passing through both ends of the piston 4, and a ball 1102, an elastic element 1103, and a retaining ring 1104 located within the flow hole 1101. One end of the flow hole 1101 facing the second cavity 8 is a small-diameter section 16 with a diameter smaller than that of the ball 1102. The retaining ring 1104 is located at the other end of the flow hole 1101. The elastic element 1103 abuts against the retaining ring 1104 and the ball 1102. In its natural state, the ball 1102 abuts against the end of the small-diameter section 16, thus blocking the flow hole 1101. Under the squeezing action of the elastic element 1103, the ball 1102 presses against the end of the small-diameter section 16, closing the one-way valve 11. When the piston 4 moves toward the first chamber 7, the ball 1102 has inertia to move toward the small diameter section 16, and the one-way valve 11 remains closed. When the piston 4 moves toward the second chamber 8, the ball 1102 moves away from the small diameter section 16 under the action of inertia, thereby making the small diameter section 16 open and the one-way valve 11 open.

[0035] The bottom of the cylinder 2 is provided with a base 17, and the base 17 is provided with mounting holes 19 for fixing to the support platform 13.

[0036] Example 2

[0037] Based on Embodiment 1, the end of the piston rod 3 is further provided with a guide wedge 20 located above the guide wheel 5. The guide wedge 20 contacts and guides the flange surface of the offshore platform 6. During initial assembly, the offshore platform 6 is inserted from top to bottom between the four dampers 1. The offshore platform 6 first contacts the guide wedge 20, thereby pushing the piston rod 3 to retract. The dampers 1 generate damping force. When the guide wheel 5 contacts the inclined surface of the flange 12, the offshore platform 6 is installed in place.

[0038] That is, after the offshore platform 6 is installed in place, the piston rod 3 of each damper 1 is in a semi-retracted state under the compression of the offshore platform 6. When the supporting platform 13 is subjected to instantaneous impact, the piston rod 3 of the damper 1 that is compressed (such as the first damper 14 in Embodiment 1) can continue to retract, and the piston rod 3 of the damper 1 that is released from compression (such as the second damper 15 in Embodiment 1) can extend.

[0039] In a further design, a support seat is provided on the outer surface of the cylinder 2, and the guide wedge 20 slides in conjunction with the support seat. The support seat can provide support for the guide wedge 20, reducing the force on the guide wheel 5.

[0040] The guide wedge 20 is formed by welding and machining of a two-dimensional stainless steel plate. Since the piston rod 3 cannot withstand large radial forces, this would increase the friction at the seal and accelerate wear. The smaller the angle between the inclined surface of the guide wedge 20 and the vertical direction, the smaller the radial component force on the piston rod 3. However, too small an angle will increase the height of the guide wedge 20. Taking all factors into consideration, the angle between the guide wedge 20 and the vertical direction is 8°~10°.

[0041] Example 3

[0042] Based on the above embodiments, in order to enable the damper 1 of the present invention to be used in deep-sea operations (450m underwater), both ends of the piston rod 3 extend out of the cylinder 2. External seawater pressure can be transmitted through the piston rod 3 and act on both sides of the piston 4. In this embodiment, the diameters of the piston rod 3 at both ends are the same, and the axial forces generated by the seawater pressure can cancel each other out, so the piston 4 will not "move on its own" due to the hydrostatic pressure difference.

[0043] Example 4

[0044] Based on the above embodiments, this embodiment designs the sealing structure in damper 1 for deep-sea operations, and the specific structure is as follows:

[0045] like Figure 5As shown, the cylinder 2 includes a cylinder body 201 and guide sleeves 202 located at both ends of the cylinder body 201. The guide sleeves 202 are in sealing contact with the piston rod 3. Between the contact surfaces of the guide sleeves 202 and the piston rod 3, a dustproof ring 22, a first U-ring 23, a second U-ring 24, a support belt 25, and a Glyd ring 18 are arranged axially from the outside to the inside of the cylinder 2. The dustproof ring 22 is made of PTFE material, which has a low coefficient of friction, high strength, good high and low temperature performance, and waterproof and pressure-resistant properties, and has a good removal effect on planktonic organisms attached to the surface of the piston rod 3. The first U-ring 23 and the second U-ring 24 are made of HPU material, and the installation direction of the first U-ring 23 is outward to prevent seawater leakage after the dustproof ring 22 fails. The installation direction of the second U-ring 24 is inward, mainly used for internal pressure sealing of the cylinder and prevention of leakage. The support band 25 is mainly used for supporting and guiding the piston rod 3. The Glyd ring 18 is the main seal of the piston rod 3, which mainly plays the role of pressure sealing. It can withstand high pressure and has a two-way sealing effect.

[0046] In the description of this invention, it should be understood that the terms "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0047] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a mechanical connection or an electrical connection; it can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. Furthermore, in the description of this invention, unless otherwise stated, "several" means two or more.

[0048] In this specification, the illustrative expressions of the terms do not necessarily refer to the same embodiments. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments.

[0049] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A support system for an offshore platform, characterized in that: It includes an offshore platform, a support platform, and several dampers. The dampers include a cylinder, a piston rod, a piston, and a guide wheel connected to one end of the piston rod. The guide wheel is in contact with and supports the flange surface of the offshore platform. The piston divides the cylinder into a first chamber and a second chamber, both filled with damping medium. A return spring is provided in the first chamber. There is a radial clearance between the piston and the cylinder. In the free state, the piston rod extends towards the guide wheel under the action of the return spring. A one-way valve is provided inside the piston. When the piston moves towards the first chamber, the one-way valve is closed. When the piston moves towards the second chamber, the one-way valve is open. The dampers are evenly distributed along the outer periphery of the offshore platform, and the cylinder of the damper is fixed to the supporting platform. The piston rod end is also equipped with a guide wedge located above the guide wheel, which contacts and guides the flange surface of the offshore platform. The one-way valve includes a flow hole penetrating both ends of the piston, and a ball, an elastic element, and a retaining ring located within the flow hole. The end of the flow hole facing the second cavity has a smaller diameter section than the ball, and the retaining ring is located at the other end of the flow hole. The elastic element abuts against the retaining ring and the ball. In its natural state, the ball abuts against the end of the smaller diameter section to seal the flow hole. Both ends of the piston rod extend out of the cylinder. The outer surface of the cylinder is provided with a support. The cylinder has a base at its bottom, with mounting holes for fixing to the support platform. The cylinder includes a body and guide sleeves at both ends. The guide sleeves are in sealed contact with the piston rod. Between the contact surfaces of the guide sleeves and the piston rod, axially from the outside to the inside of the cylinder, a dustproof ring, a first U-ring, a second U-ring, a support belt, and a Glyd ring are sequentially arranged. The dustproof ring is made of PTFE, and the first and second U-rings are made of HPU. The first U-ring is installed outwards, and the second U-ring is installed inwards. The angle between the guide wedge and the vertical direction is 8°~10°.

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