CN113216121B - A stable support device for an offshore drilling platform and using method - Google Patents

Abstract

A stable supporting device of an offshore drilling platform and a using method thereof are provided, the device comprises a pile stabilizing platform, a pendulum system and an anti-toppling system; the pile stabilizing platform comprises a steel cofferdam and auxiliary supporting columns symmetrically arranged on the periphery of the steel cofferdam; the pendulum system comprises a supporting rod hinged with the auxiliary supporting column and a heavy hammer fixedly connected to the tail end of the supporting rod, and a jack used for driving the supporting rod to rotate around a hinged point is arranged between the auxiliary supporting column and the supporting rod; the anti-toppling system comprises a steel plate stress test probe, a wave force sensor and a controller, wherein the wave force sensor and the steel plate stress test probe are connected with the controller, the controller analyzes and processes data collected by the wave force sensor and the steel plate stress test probe and controls the movement of a telescopic rod of the jack, so that the swinging frequency and the swinging amplitude of the pendulum system are controlled, the pendulum system releases counter-acting force for offsetting wave force, and the problem that a supporting device of the offshore drilling platform cannot be adjusted in real time according to relevant weather conditions is solved.

Description

A stable support device for an offshore drilling platform and its use method

technical field

The invention relates to the field of stability of an offshore large-diameter pile foundation drilling platform, in particular to a stable support device for an offshore drilling platform and a method of using the same.

Background technique

With the development of the national economy, my country's traffic has gradually shifted from cross-river bridges to ultra-long sea-crossing bridges, and due to the development of new energy industries, my country's wind power generation base stations have gradually developed from offshore to deep seas. However, these projects generally need to be run through The pile foundation structure is the engineering foundation. Currently, the construction of large-diameter pile foundations in the deep sea area generally includes two types: the drilling and re-driving scheme and the implanted rock-socketing scheme. In the deep sea environment, since most of the piles are in the sea, not only the lower strata need to provide strong bearing capacity, but also the horizontal circulation of wind, waves, ocean currents and other disastrous loads in Changji, as well as earthquakes and turbidity currents on the seabed. Therefore, the pile foundation in the deep sea needs to consider not only the vertical bearing capacity, but also the horizontal bearing capacity and the verticality of the cofferdam. Therefore, the burial depth of the foundation and the embedded strength of the lower stratum are relatively high.

The above two construction schemes both require the establishment of a temporary piling drilling frame on the sea. Such frames are generally temporary supports and have a low embedded depth. Therefore, the casing of the steel cofferdam for well protection is placed on the seabed. The self-weight of the weir is large, so the cofferdam will be embedded in the softer soil layer or soft rock layer 2-3m above the seabed, and relevant support devices will be set around the steel cofferdam. , the cofferdam is easy to incline or needs to be hoisted and disassembled, so the wind and wave load resistance of the wellbore under the action of strong wind and waves is particularly important. In the past, most of the support forms were to set supporting members on the outer ring of the wellbore to reinforce the bottom of the wellbore obliquely or constrain it at the top. It is time-consuming and labor-intensive, and most of them are mechanical components, which cannot be adjusted in real time according to relevant climatic problems.

SUMMARY OF THE INVENTION

The present invention aims to provide a stable support device for an offshore drilling platform and a method for using it, so as to solve the problem that the support device of the offshore drilling platform cannot be adjusted in real time according to relevant climatic conditions.

In order to solve the above technical problems, the specific scheme adopted in the present invention is: a stable support device for an offshore drilling platform, including a pile stabilization platform, a pendulum system and an anti-dumping system; The auxiliary support column on the outer periphery, the steel cofferdam and the auxiliary support column are connected by a steel truss; the pendulum system includes a support rod hinged with the auxiliary support column and a weight fixedly connected to the end of the support rod. The jack is used to drive the support rod to rotate around the hinge point; the anti-tipping system includes a steel plate force test probe, a wave force sensor and a controller. The steel plate force test probe is set on the outer wall of the steel cofferdam, and the wave force sensor is set on the auxiliary support column. The outer side wall, the wave force sensor and the steel plate force test probe are all connected to the controller. The controller analyzes and processes the data collected by the wave force sensor and the steel plate force test probe. Movement, thereby controlling the oscillation frequency and the oscillation amplitude of the pendulum system, so that the pendulum system releases the reaction force for counteracting the wave force.

Preferably, the number of auxiliary support columns is four.

Preferably, the steel truss includes a first steel truss and a second steel truss, the number of the first steel truss and the second steel truss is four, all the first steel trusses are arranged symmetrically and radially relative to the steel cofferdam, and the One end is welded to the guide sleeve of the steel cofferdam outside the steel cofferdam, the other end of the first steel truss is welded to the middle position of the second steel truss, and the two ends of the second steel truss are welded to the adjacent two sleeves set in the auxiliary On the auxiliary support column guide sleeve on the support column, the auxiliary support column and the upper part of the inner hole of the auxiliary support column guide sleeve are clearance fit, and the lower part of the auxiliary support column and the inner hole of the auxiliary support column guide sleeve are connected by a clip key, and the clip key is connected. The axial clearance is adjusted by the screw, and all the second steel trusses are connected into a square, making the whole drilling platform a large-strength space structure.

Preferably, the number of wave force sensors is multiple and distributed on the outer side wall of the auxiliary support column along the height direction of the auxiliary support column, the distance between adjacent wave force sensors is 0.25m, and the number of steel plate force testing probes is multiple It is distributed on the outer side wall of the steel cofferdam along the height direction of the steel cofferdam, and the distance between the adjacent steel plate force test probes is 0.25m.

Preferably, the mass of each weight is 25% of the mass of the steel cofferdam.

Preferably, the length of the support rod is 1/2 of the height of the steel cofferdam.

Preferably, the shell of the jack is welded on the auxiliary support column, and the telescopic rod of the jack is slidably supported with the support rod.

A method for using a stable support device for an offshore drilling platform, comprising the following steps:

S1, wave force data collection

The wave force sensor tests the frequency and amplitude of wave force strikes in all directions and transmits the data to the controller;

S2, the anti-dumping system controls the swing of the heavy hammer

The controller analyzes and processes the received data. As the wave force sensor measures the surrounding wave force, it analyzes the wave force in each direction and the cycle period. The controller drives the telescopic rod of the jack to move the four pendulum weights against each other The wave force swings in the opposite direction, exerting a reaction force on the wave force, thereby offsetting the force of the wave force;

S3. Force data collection of steel cofferdam

After applying the reaction force to the wave force, test the stress distribution on the steel cofferdam through the steel plate force test probe, and transmit the stress distribution data to the controller;

S4, the formation of the pendulum effect

By analyzing the wave force and the stress distribution of the steel cofferdam, the controller adjusts the swing amplitude and the swing frequency of the pendulum body in different directions of the pendulum system in real time to form a pendulum effect and offset the impact of the wave force on the steel cofferdam. The steel cofferdam remains vertical.

Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This scheme is improved on the basis of the original offshore drilling support project, and skillfully uses the interactive swing of the double pendulums in the same direction, thereby realizing the small-amplitude swing of the heavy hammer. The entire pendulum effect is formed, the stability of the drilling is improved, the supporting structure is relatively simple to erect, and a large amount of waste of supporting steel is reduced. 2. This scheme utilizes the semi-swing of the left and right heavy hammers to form a full pendulum cycle of the drilling platform. The frequency of the pendulum is adjusted by the anti-dumping system to offset the wave cyclic load, effectively reducing the horizontal force on the steel cofferdam. The stability of the platform is improved, and the swing frequency can be corrected in real time according to the size of the wind and waves at sea, which can maintain the stable period of the platform, help reduce the impact of strong wind and waves on the steel cofferdam, and effectively prolong the effective construction time. 3. This scheme has changed the previous construction scheme of rigid support for offshore platforms. Since most of the structures of offshore platforms are above the seabed, this scheme uses seawater space to establish a pendulum system, and uses the flexible pendulum effect to counteract the effect of wave loads. , so that the verticality of the offshore platform can be effectively guaranteed. For the long-term complex and changeable cyclic loads on the sea, the temporary or even long-term stable support platform is built, which improves the strength of its resistance to horizontal loads, and has the advantages of fast construction speed and low cost.

Description of drawings

Fig. 1 is the side sectional view of the overall structure of the present invention;

2 is a top view of the overall structure of the present invention;

Fig. 3 is the schematic diagram of the force condition of the present invention in a certain period of time;

Reference numerals: 1, support rod, 2, heavy hammer, 3, jack, 4, wave force sensor, 5, auxiliary support column, 6, steel plate force test probe, 7, steel cofferdam, 8, steel cofferdam guide Sleeve, 9. First steel truss, 10. Second steel truss, 11. Guide sleeve for auxiliary support column.

Detailed ways

As shown in Figure 1, a stable support device for an offshore drilling platform includes a pile stabilization platform, a pendulum system and an anti-dumping system.

The pile stabilization platform includes a steel cofferdam 7 and an auxiliary support column 5 symmetrically arranged on the outer periphery of the steel cofferdam 7. The number of the auxiliary support columns 5 is four, which are evenly distributed in the four directions of the front, rear, left and right of the steel cofferdam 7. 7 and the auxiliary support column 5 are connected by a steel truss, the steel truss includes a first steel truss 9 and a second steel truss 10, the number of the first steel truss 9 and the second steel truss 10 is four, all the first steel truss 9 Relative to the steel cofferdam 7 in a symmetrical radial arrangement, one end of the first steel truss 9 is welded to the steel cofferdam guide sleeve 8 outside the steel cofferdam 7 , and the other end of the first steel truss 9 is welded to the middle position of the second steel truss 10 , the two ends of the second steel truss 10 are respectively welded on two adjacent auxiliary support column guide sleeves 11, the auxiliary support column guide sleeve 11 is sleeved on the auxiliary support column 5, and the auxiliary support column 5 and the auxiliary support column guide sleeve The upper section of the inner hole of 11 is a relatively precise clearance fit. The gap between the auxiliary support column 5 and the lower section of the inner hole of the auxiliary support column guide sleeve 11 is slightly larger and is connected by a card key. The axial gap of the card key connection is adjusted by the screw. The two steel trusses 10 are connected to form a square, making the entire drilling platform a high-strength spatial structure.

The pendulum system includes a support rod 1 hinged with an auxiliary support column 5 and a weight 2 fixedly connected to the end of the support rod 1. The support rod 1 is hinged on the side of the auxiliary support column 5 that is opposite to the steel cofferdam 7. The auxiliary support column 5 A jack 3 for driving the support rod 1 to rotate around the hinge point is arranged between the support rod 1 and the support rod 1. The shell of the jack 3 is welded on the auxiliary support column 5, and the telescopic rod of the jack 3 is slidingly supported with the support rod 1. The position where the telescopic rod and the support rod 1 are slidably supported and matched is set in the upper middle part of the support rod 1 . The length of the support rod 1 is 1/2 of the height of the steel cofferdam 7 , and the mass of each weight 2 is 25% of the mass of the steel cofferdam 7 .

The anti-dumping system includes a steel plate force test probe 6, a wave force sensor 4 and a controller. The number of steel plate force test probes 6 is multiple and arranged on the outer side wall of the steel cofferdam 7 along the height direction of the steel cofferdam 7. , the distance between the adjacent steel plate force test probes 6 is 0.25m, the number of wave force sensors 4 is multiple and distributed along the height direction of the auxiliary support column 5 on the outer side wall of the auxiliary support column 5, adjacent wave force sensors 4 The distance is 0.25m, and the wave force sensor 4 and the steel plate force test probe 6 are both connected to the controller. The controller analyzes and processes the data collected by the wave force sensor 4 and the steel plate force test probe 6. The data controls the movement frequency and amplitude of the telescopic rod of the jack 3, thereby controlling the swing frequency and the swing amplitude of the pendulum system, so that the pendulum system releases the reaction force for counteracting the wave force.

In addition, the axial clearance of the card key connection can also be adjusted by screws; the telescopic rod of the jack and the support rod can also be hinged through the hinge seat, and the distance between the hinge point and the hinge point of the support rod and the auxiliary support column is the length of the support rod. 1/4.

In order to facilitate the understanding of the above technical solutions of the present invention, the working principle or operation mode of the present invention in the actual process will be described in detail below.

Taking the use of the stable support device of the offshore drilling platform to drill the installation holes of the wind power foundation pile foundation as an example, the specific operation steps are as follows:

1) Installation of stable support device for offshore drilling platform

① Assemble the stable support device of the offshore drilling platform composed of the stabilized pile platform, the pendulum system and the anti-dumping system, and then lift the whole to sink into the water. Under the action of its own weight, the steel cofferdam 7 and the auxiliary support column 5 sink into the seabed for a certain amount The depth of the steel cofferdam 7 and the auxiliary support column 5 submerged into the seabed is calculated to meet the stability requirements.

②Selectively apply certain vibration to the top of the auxiliary support column 5 and the steel cofferdam 7 to level the platform.

3. Disassemble the key of an auxiliary support column 5, drive the auxiliary support column 5 into the rock surface with a vibrating hammer, and after it is in place, connect and install the key of the auxiliary support column 5 again, and repeat the above process one by one. The auxiliary support column 5 is driven in. Since the platform is symmetrically supported by four auxiliary support columns 5, the platform remains stable and level even when only one auxiliary support column 5 is removed at a time.

④ Pre-tighten the locking screws on the guide sleeve of the steel cofferdam 7 to connect the upper port of the steel cofferdam 7 with the platform. When the stable support device of the offshore drilling platform is used for offshore thin soft formations, the steel cofferdam 7 and the auxiliary support column 5 must be driven to the rock surface when driving.

When the drilling platform is used for the construction with thin overburden layer, especially in a few areas where the overburden layer is only 2-3m thick, since the steel cofferdam 7 is driven into the stratum shallowly, the stratum around the steel cofferdam 7 is easily damaged by the steel cofferdam 7. The pressure of the liquid column in 7 breaks down, which leads to the increase of the gas lift and directly affects the drilling efficiency. In order to improve the drilling efficiency, in addition to reducing the height of the drilling platform from the sea level as much as possible, the overall sand bag box scheme will be adopted in this plan: the annular overall sand bag box is suspended at the lower end of the platform with a steel wire rope, and the water enters the platform along with the sand bag box. The bottom of the bag box and the lower opening of the auxiliary support column 5 contact the seabed surface at the same time, and as the auxiliary support column 5 is pressed into the seabed by the weight of the offshore drilling platform, it is completely pressed on the seabed surface around the steel cofferdam 7 to reinforce The soft foundation around the steel cofferdam 7 improves the ability of the formation around the steel cofferdam 7 to be broken down by the pressure in the hole when drilling.

2) Work through the stable support device of the offshore drilling platform to maintain the stability of the offshore drilling platform

S1, wave force data collection

The wave force sensor 4 tests the frequency and amplitude of wave force strikes in all directions and transmits the data to the controller;

S2, the anti-dumping system controls the swing of the heavy hammer 2

The controller analyzes and processes the received data, and adjusts the vibration frequency of the pendulum according to the force of the sensor force. The situation of the force, analyze the wave force in each direction and the cycle period, the controller drives the movement of the telescopic rod of the jack 3 to make the four pendulum weights 2 swing in the opposite direction to the wave force, exerting a reaction force on the wave force, thereby offsetting the wave force of force;

S3, steel cofferdam 7 force data collection

After applying the reaction force to the wave force, test the stress distribution on the steel cofferdam 7 through the steel plate force test probe 6, and transmit the stress distribution data to the controller;

S4, the formation of the pendulum effect

By analyzing the wave force and the stress distribution of the steel cofferdam 7, the controller adjusts the swing amplitude and the swing frequency of the pendulum body in different directions of the pendulum system in real time to form a pendulum effect and offset the impact of the wave force on the steel cofferdam 7, and then The steel cofferdam 7 is kept vertical continuously.

3) Maintain verticality during drilling

The drilling rig is hoisted to the drilling platform, and a hole with a diameter larger than the outer diameter of the wind power foundation pile is drilled in the seabed stratum. During the drilling process, considering the long drilling time, wind and wave current and the vibration of the drilling rig during the drilling process, the drilling platform will be tilted to a certain extent, resulting in the verticality of the drilling hole being out of tolerance. The verticality of the platform needs to be detected. When tilting occurs, the levelness of the platform can be adjusted by adjusting the keys on each auxiliary support column 5 . For situations where the borehole has fully entered the stable rock formation, the drilling rig can circulate clean water. When the drilling depth reaches the design bottom elevation of the wind power foundation pile foundation, stop drilling and move the drilling rig away.

The following is the data monitored during a certain period of time when the stable support device of the offshore drilling platform works to maintain the stability of the platform, as shown in Figure 3:

The wave force sensor 4 detects a wave cyclic load with a maximum wave force of 500kn in one direction and a period t of 7s. After 30s, the wave force gradually becomes 400kn and the period is 7s.

The wave force sensor 4 receives the signal at the initial stage and transmits it to the controller. After the controller calculates and analyzes the data, it controls the jack 3 of the pendulum system for the two pendulums in the direction, so that the weight 2 gradually generates a 500kn cycle with an opposite period. load, which further counteracts the wave cyclic load. From the analysis of the stress sensor of the steel cofferdam 7, it can be seen that the lateral cyclic load in this direction decreases from the maximum 500kn to the low-amplitude vibration of 50kn, and the wave force decreases after 30s. After the wave force decreases, the wave sensor will change the information of the wave. It is transmitted to the controller, and the swing amplitude of the pendulum system is changed after analysis by the controller, thereby changing the force and frequency of the pendulum, thereby reducing the lateral force of the steel cofferdam 7 .

Claims (6)

1. A stable support device for an offshore drilling platform, characterized in that it comprises a pile-stabilizing platform, a pendulum system and an anti-dumping system; the pile-stabilizing platform comprises a steel cofferdam (7) and a The auxiliary support column (5), the steel cofferdam (7) and the auxiliary support column (5) are connected by a steel truss; the pendulum system includes a support rod (1) hinged with the auxiliary support column (5) and a support rod (1) fixedly connected to the support rod (1). ) at the end of the weight (2), between the auxiliary support column (5) and the support rod (1), a jack (3) for driving the support rod (1) to rotate around the hinge point is provided. The mass is 25% of the mass of the steel cofferdam (7), and the length of the support rod (1) is 1/2 of the height of the steel cofferdam (7). 4) and the controller, the steel plate force test probe (6) is arranged on the outer wall of the steel cofferdam (7), the wave force sensor (4) is arranged on the outer wall of the auxiliary support column (5), and the wave force sensor (4) and the steel plate force test probe (6) are connected to the controller, the controller analyzes and processes the data collected by the wave force sensor (4) and the steel plate force test probe (6), and the controller controls the jack ( 3) The movement of the telescopic rod, thereby controlling the swing frequency and the swing amplitude of the pendulum system, so that the pendulum system releases the reaction force used to counteract the wave force. 2 . The stable support device for an offshore drilling platform according to claim 1 , wherein the number of auxiliary support columns ( 5 ) is four. 3 . 3. A stable support device for an offshore drilling platform according to claim 2, characterized in that the steel truss comprises a first steel truss (9) and a second steel truss (10), the first steel truss (9) and The number of the second steel trusses (10) is four, all the first steel trusses (9) are arranged symmetrically and radially relative to the steel cofferdam (7), and one end of the first steel truss (9) is welded to the steel cofferdam (7) On the outer steel cofferdam guide sleeve (8), the other end of the first steel truss (9) is welded to the middle position of the second steel truss (10), and the two ends of the second steel truss (10) are welded to the adjacent ones. Two auxiliary support column guide sleeves (11) sleeved on the auxiliary support column (5), the auxiliary support column (5) and the upper section of the inner hole of the auxiliary support column guide sleeve (11) are in clearance fit, and the auxiliary support column ( 5) The lower part of the inner hole of the guide sleeve (11) of the auxiliary support column is connected by a key, and the axial clearance of the key connection is adjusted by the screw, and all the second steel trusses (10) are connected into a square, so that the whole drilling platform become a large-strength spatial structure. 4. A stable support device for an offshore drilling platform according to claim 1, characterized in that the number of wave force sensors (4) is multiple and arranged on the auxiliary support column along the height direction of the auxiliary support column (5). On the outer side wall of (5), the distance between adjacent wave force sensors (4) is 0.25m, and the number of steel plate force test probes (6) is multiple and distributed along the height direction of the steel cofferdam (7). On the outer side wall of the cofferdam (7), the distance between the adjacent steel plate force test probes (6) is 0.25m. 5. A stable support device for an offshore drilling platform according to claim 1, characterized in that the shell of the jack (3) is welded on the auxiliary support column (5), and the telescopic rod of the jack (3) and the support rod (1) Sliding support fit. 6. the using method of the stable support device of a kind of offshore drilling platform according to claim 1, is characterized in that: comprise the following steps: S1, wave force data collection The wave force sensor (4) tests the frequency and amplitude of wave force strikes in all directions and transmits the data to the controller; S2, the anti-dumping system controls the swing of the heavy hammer The controller analyzes and processes the received data, analyzes the wave force in each direction and the cycle period as the wave force sensor (4) measures the surrounding wave force, and the controller drives the telescopic rod movement of the jack (3) to make The four pendulum weights oscillate in the opposite direction to the wave force, exerting a reaction force on the wave force, thereby counteracting the force of the wave force; S3. Force data collection of steel cofferdam After applying the reaction force to the wave force, test the stress distribution on the steel cofferdam (7) through the steel plate force test probe (6), and transmit the stress distribution data to the controller; S4, the formation of the pendulum effect By analyzing the wave force and the stress distribution of the steel cofferdam (7), the controller adjusts the swing amplitude and the swing frequency of the pendulum body in different directions of the pendulum system in real time to form a pendulum effect and offset the impact of the wave force on the steel cofferdam (7). ), so that the steel cofferdam (7) remains vertical.

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