CN202510918U - W-shaped device for inhibiting vortex induced vibration of marine riser - Google Patents

Abstract

The utility model relates to a device for inhibiting vortex induced vibration of a marine riser. The device is formed by combining a plurality of basic units in serial mode along the axial direction of the riser. Each basic unit is a whole formed by a guide cover and a single W-shaped turbulence plate arranged on the guide cover and is processed by a plastic mould. The guide cover is of a cylindrical structure with the inner diameter equal to the outer diameter of the riser, the turbulence plate expands along the peripheral direction to form a W shape, the cross section of the turbulence plate is an isosceles triangle, the turbulence plate is arranged in the middle of the guide cover, and the distance between the turbulence plate and the upper edge and the lower edge of the guide cover is the same. The guide covers with the W-shaped turbulence plates are sleeved outside the riser in serial mode, vortex induced vibration can be effectively inhibited from different flow coming directions, and the influence of the vortex induced vibration on fatigue service life of the riser is reduced. The W-shaped device for inhibiting vortex induced vibration of the marine riser is light in weight, low in manufacture cost and not easy to corrode and damage.

Description

A W-shaped marine riser vortex-induced vibration suppression device

technical field

The utility model belongs to the technical field of marine riser facilities laying, in particular to a novel suppression device capable of effectively suppressing vortex-induced vibration of marine risers.

Background technique

The offshore oil riser is a casing from the offshore drilling platform to the shallow seabed. Its main function is to isolate seawater, form a drilling fluid circulation channel, and serve as a supporting structure for the offshore wellhead. The integrity of the riser is critical to the safety of offshore operations. The riser is continuously subjected to compound loads such as waves and currents in the ocean. When the sea current bypasses the riser, pressure difference resistance is formed before and after the riser, and a drag force is formed on its cylindrical surface, thereby causing the riser to vibrate longitudinally; In addition, vortices alternately shed on both sides behind the riser, causing the lift force perpendicular to the flow direction to be additionally applied to the riser, and the alternate change of the lift direction causes the riser to vibrate laterally, and this vibration is more severe; when When the vortex shedding frequency is close to a certain natural frequency of the riser vibration, the vibration of the structure will force the vortex shedding frequency to be fixed at a certain natural frequency of the cylinder within a large flow velocity range, and a locking phenomenon occurs, that is, resonance, which causes the riser to fatigue failure. Once the riser fatigue damage occurs, it will not only cause major safety accidents at sea, cause huge economic losses, but also cause catastrophic damage to the marine environment.

The existing riser vortex-induced vibration suppression device has the disadvantages of high cost, complicated manufacturing process, heavy weight, cumbersome installation and inconvenient on-site operation.

Contents of the invention

The problem to be solved by the utility model is to provide a new type of marine riser with simple structure, light weight, reliable performance, low cost, convenient on-site installation, and not easy to corrode and damage in view of the shortcomings of the existing marine riser suppressing vortex-induced vibration devices. Water pipe vortex induced vibration suppression device.

The utility model adopts the following technical scheme: the W-shaped marine riser vortex-induced vibration suppression device is composed of a plurality of basic units arranged in series along the axial direction of the riser. The whole body composed of the flow plate is processed by plastic mold; the flow guide cover is a cylindrical structure with an inner diameter equal to the outer diameter of the riser; the spoiler is deployed in a W shape along the circumference, and its section is an isosceles triangle. Arranged in the middle of the wind deflector, the distance from the upper and lower edges of the wind deflector is equal. In the utility model, a flow guide cover with a W-shaped spoiler is arranged in series outside the water riser, which can effectively suppress vortex-induced vibration from different incoming flow directions, and reduce its influence on the fatigue life of the water riser.

The utility model also includes:

1. The thickness of the shroud is 0.025~0.035 times of the outer diameter D of the riser, and the axial length L of the shroud is 1.5~2 times of the W-shaped height H of the spoiler;

2. The cross section of the spoiler is an isosceles triangle, the length s of the bottom side is 0.05D~0.12D, and the height h is 0.15D~0.35D; the angle θ at the turning point after the spoiler is deployed along the circumferential direction is 60o~ 120o; the turning point is a circular arc with a radius R of 0.08D~0.15D; the spoiler is arranged in the middle of the spoiler, and the distance T from the upper and lower edges of the spoiler is 0.25L~0.5L;

3. The spoiler and the shroud are formed by a plastic mold at one time.

The utility model has the following advantages:

1. The spoiler and the deflector of the device are integrated, which are set on the outer surface of the riser, and the installation is simple;

2. The material of the deflector and spoiler of this device is plastic, which can greatly reduce the cost, simplify the manufacturing process, not easy to corrode and damage, and can be reused;

3. The spoiler of this device can effectively slow down the vortex-induced vibration caused by different incoming flow directions;

4. This device can properly adjust the distance between each basic unit according to the actual situation on site, so as to achieve the best suppression effect.

Description of drawings

Fig. 1 is a three-dimensional schematic diagram of three basic units of the utility model assembled in series;

Fig. 2 three-dimensional schematic diagram of the basic unit of the utility model;

Fig. 3 is a schematic diagram of the utility model deployed along the circumferential direction;

Fig. 4 is the schematic plan view of the basic structure of the utility model;

Fig. 5 A-A sectional schematic diagram of the utility model spoiler.

Among them: 1. Riser, 2. Spoiler, 3. Spoiler.

Detailed ways

The utility model W-shaped marine riser vortex-induced vibration suppression device is composed of a plurality of basic units arranged in series along the axial direction of the riser, and the basic unit is composed of a flow guide cover and a single W-shaped spoiler on it. As a whole, it is processed by a plastic mold; the thickness of the shroud is 0.025~0.035 times the outer diameter D of the riser, and the axial length L of the shroud is 1.5~2 times the height H of the W shape of the spoiler; The cross section of the spoiler is an isosceles triangle, the length s of the base is 0.05D~0.12D, and the height h is 0.15D~0.35D; the angle θ at the turning point after the spoiler is deployed along the circumferential direction is 60o~120o; The position is an arc with a radius R of 0.08D~0.15D; the spoiler is arranged in the middle of the spoiler, and the distance T from the upper and lower edges of the spoiler is 0.25L~0.5L.

As shown in Figure 1, the basic units are set in series on the outer surface of the riser, and the W-shape of the upper and lower basic units must be aligned so that the line connecting the convex or concave parts of the upper and lower spoilers is parallel to the axis of the riser . The distance between the basic units is usually 0.2L~1.5L, and it can also be adjusted appropriately according to the actual situation to achieve the best suppression effect.

Claims (4)

1. the utility model relates to a kind of W font ocean marine riser vortex-induced vibration suppression device, it is characterized in that: combine along marine riser axial direction tandem by a plurality of elementary cells, elementary cell be air guide sleeve and on the integral body that constitutes of single W font spoiler; Air guide sleeve is the cylindrical structure that internal diameter equals the marine riser D outer diameter; Spoiler becomes the W font along circumferentially deploying, and it highly is H, and section is an isosceles triangle, and angle is θ to spoiler in the turning point behind circumferentially deploying, and the turnover transition position is that radius is the circular arc of R; Spoiler is arranged in the middle part of air guide sleeve, is T apart from the Edge Distance up and down of air guide sleeve.

2. W font as claimed in claim 1 ocean marine riser vortex-induced vibration suppression device, it is characterized in that: the thickness of air guide sleeve is 0.025D ~ 0.035D, the axial length L of air guide sleeve is 1.5H ~ 2H.

3. W font as claimed in claim 1 ocean marine riser vortex-induced vibration suppression device is characterized in that: the W font height H of spoiler behind the circumferentially deploying is 1.2D ~ 2.4D; The cross section of spoiler is an isosceles triangle, and bottom side length s is 0.05D ~ 0.12D, and high h degree is 0.15D ~ 0.35D; Spoiler angle theta of turning point behind the circumferentially deploying is 60o ~ 120o; The turning point is that radius R is the circular arc of 0.08D ~ 0.15D; Spoiler is arranged in the middle part of air guide sleeve, is 0.25L ~ 0.5L apart from the T of Edge Distance up and down of air guide sleeve.

4. W font as claimed in claim 1 ocean marine riser vortex-induced vibration suppression device, it is characterized in that: spoiler and air guide sleeve are an integral body, by the moulding of plastic mould time processing.

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