CN116607489A - Pile leg replacement method for self-elevating wind power platform - Google Patents

Abstract

The invention relates to the field of wind power platform construction, and provides a method for replacing pile legs of a self-elevating wind power platform, which comprises the following steps: dividing old pile legs into a first old pile leg section, a second old pile leg section and a bottom old pile leg section; removing the old pile leg of the first section, and removing the old pile shoe and the old pile leg at the bottom; taking out the pile fixing chamber on the second old pile leg, and removing the second old pile leg; discharging a docking block, and placing the new pile shoe on the temporary docking block; the novel pile leg at the bottom is lowered and locked through the locking device of the pile leg bolt oil cylinder of the platform; and hoisting the first section of new pile leg and the second section of new pile leg through the floating crane. According to the pile leg replacement method for the self-elevating wind power platform, provided by the invention, old pile legs are removed in sections, new pile legs are installed in sections, and the requirement on a crane is reduced; different parts of the old pile leg are removed in different modes, so that the removal efficiency of the old pile leg is improved; after the old pile leg of the first section is removed, the old pile shoe is removed and transferred in the dock, so that safety is ensured.

Description

Pile leg replacement method for self-elevating wind power platform

Technical Field

The invention relates to the field of wind power platform construction, in particular to a pile leg replacement method for a self-elevating wind power platform.

Background

With the shortage of global energy and the increasing severity of environmental pollution, wind power generation is rapidly developed as pollution-free renewable energy, and the development of offshore wind energy is increasingly emphasized due to limited land space and high offshore wind energy density. The self-elevating offshore wind power installation platform lifts the platform to a certain height through the cooperation of the spud legs and the lifting system so as to adapt to different water depths and operation heights.

In recent years, the scale of the wind power generator is larger and larger, so that the traditional wind power installation platform cannot meet the requirements, and the pile legs of the wind power installation platform need to be replaced. If the pile leg is removed only according to the length and the weight of the pile leg, the problem of low efficiency exists, and the possibility that the pile shoe falls off when the pile leg at the bottom is lifted exists, so that unnecessary and great economic loss, even casualties, are caused.

Disclosure of Invention

The invention provides a pile leg replacing method and system for a self-elevating wind power platform, and aims to provide a high-efficiency pile leg replacing method.

In a first aspect, the invention provides a method for replacing pile legs of a self-elevating wind power platform, comprising the following steps:

dividing old pile legs into a first old pile leg section, a second old pile leg section and a bottom old pile leg section in sequence according to a preset rule; the bottom old pile leg is a part of the old pile leg connected with the old pile shoe;

removing the first old pile leg;

docking the ship, and removing the old pile shoe and the old pile leg at the bottom;

the ship is driven to undock, a pile fixing chamber on the second old pile leg is taken out, and the second old pile leg is removed;

docking a driving ship, discharging a docking block according to a preset drawing, placing a new pile shoe on the temporary docking block, and installing a crescent plate and a panel on the new pile shoe;

the novel pile shoe is aligned with the positioning cross mark of the novel pile leg at the bottom by the locking device of the bolt oil cylinder of the pile leg of the platform, and the novel pile shoe is subjected to position adjustment;

and (3) the ship is driven to be undocked, the first section of new pile leg and the second section of new pile leg are hoisted through a floating crane, and the folding ports between the pile legs are welded.

In one embodiment, said removing said old shoe and said bottom old leg comprises:

lowering the rest part of the old pile leg by a first preset distance through a lifting mechanism, and filling wood between the old pile shoe bottom plate and the dock floor;

fixing the rest part of the old pile leg through a bolt of the lifting mechanism, and cutting the old pile leg and the cylinder wall of the old pile shoe to enable the old pile shoe to fall off;

removing the pile leg with the first preset length below the old pile leg at the bottom, and lowering the rest part of the old pile leg by a second preset distance through the lifting mechanism;

dismantling a second pile leg with a preset length below the old pile leg at the bottom, and lifting the old pile leg by a third preset distance through the lifting mechanism to finish the dismantling of the old pile leg at the bottom;

draining the water in the dock, and moving the old pile shoe to a dock entrance to finish the dismantling of the old pile shoe.

The second section of new pile leg is hoisted by a floating crane, and the method comprises the following steps:

after a second new pile leg is lifted for a fourth preset distance through the floating crane, checking a lifting hook, a signal and a control device of the floating crane, and checking lifting lugs and structures of the second new pile leg;

after the second section of new pile leg is erected, removing hanging rings at the lower end of the second section of new pile leg;

lifting the second section of new pile leg through a floating crane, and moving the second section of new pile leg to a platform lifting position;

and adjusting the front-back left-right direction of the second section of new pile leg and the direction of the sectional positioning tool, and lowering the second section of new pile leg into the pile leg total section positioning tool.

After welding the folding ports between the pile legs, the welding device further comprises:

flaw detection is carried out on the welding part;

and performing platform pile insertion.

Before dividing the old pile leg into the first old pile leg, the second old pile leg and the bottom old pile leg in sequence according to a preset rule, the method further comprises:

prefabricating new pile legs in sections to obtain a first section of new pile legs and a second section of new pile legs;

and integrally prefabricating the new pile shoe and the bottom pile leg.

The segmented prefabricated new leg comprises:

manufacturing a single-section pile leg;

and (5) lengthening the two single-section pile legs, and then assembling the multi-section cylinder.

The process for assembling the multi-section cylinder comprises the following steps: positioning a reference cylinder upper tire, positioning the cylinder in a sectional butt joint mode, assembling a barrel sectional annular seam, welding the annular seam, detecting the annular seam, measuring the precision after welding, installing an outfitting piece and coating the pile leg in a sectional mode.

The prefabricated new pile shoe comprises:

and synchronously installing a sacrificial anode, a pile punching system and an outfitting piece when the new pile shoe is prefabricated.

According to the pile leg replacement method for the self-elevating wind power platform, old pile legs are divided into a first old pile leg, a second old pile leg and a bottom old pile leg; removing the first old pile leg; driving the ship to dock, and removing old pile shoes and old pile legs at the bottom; the ship is driven to undock, a pile fixing chamber on the second old pile leg is taken out, and the second old pile leg is removed; docking a driving ship, discharging a docking block according to a preset drawing, placing a new pile shoe on the temporary docking block, and installing a crescent plate and a panel on the new pile shoe; the novel pile shoe is subjected to position adjustment by a platform pile leg bolt oil cylinder locking device, and the novel pile leg at the bottom is lowered and locked; and (3) the ship is driven to be undocked, the first section of new pile leg and the second section of new pile leg are hoisted through a floating crane, and the folding ports between the pile legs are welded.

The pile leg replacement method for the self-elevating wind power platform has the following advantages: the old pile leg is removed in a segmented mode, and the new pile leg is installed in a segmented mode, so that requirements on a crane are reduced; different parts of the old pile leg are removed in different modes, so that the removal efficiency of the old pile leg is improved; the novel pile leg at the bottom is locked by the locking device of the pile leg bolt oil cylinder of the platform, so that the installation precision is improved; after the old pile leg of the first section is removed, namely the old pile shoe is removed and transferred in the dock, and finally the old pile leg of the second section is removed, so that the safety is ensured.

Drawings

In order to more clearly illustrate the technical solutions of the present invention, the following description will be given with a brief introduction to the drawings used in the embodiments or the description of the prior art, it being obvious that the drawings in the following description are some embodiments of the present invention, and that other drawings can be obtained from these drawings without the inventive effort of a person skilled in the art.

FIG. 1 is a schematic flow chart of a pile leg replacement method for a self-elevating wind power platform provided by the invention;

FIG. 2 is a schematic diagram of an old pile leg structure provided by the invention;

FIG. 3 is a schematic diagram of a new leg segment prefabrication step provided by the invention;

fig. 4 is a schematic view of a new pile leg structure provided by the invention.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The embodiments of the present invention provide embodiments of a method for replacing spud legs of a self-elevating wind power platform, and it should be noted that although a logic sequence is shown in the flowchart, the steps shown or described may be accomplished in a different sequence than that shown or described herein under certain data.

Referring to fig. 1, fig. 1 is a schematic flow chart of a pile leg replacement method for a self-elevating wind power platform provided by the invention. The pile leg replacement method for the self-elevating wind power platform provided by the embodiment of the invention comprises the following steps:

step 101, dividing old pile legs into a first old pile leg, a second old pile leg and a bottom old pile leg in sequence according to a preset rule; the bottom old pile leg is a part of the old pile leg connected with the old pile shoe;

102, dismantling the first old pile leg;

step 103, driving the ship to dock, and removing the old pile shoe and the old pile leg at the bottom;

step 104, driving the ship to undock, taking out a pile fixing chamber on the second old pile leg, and removing the second old pile leg;

step 105, driving a ship to dock, discharging a docking block according to a preset drawing, placing a new pile shoe on the temporary docking block, and installing a crescent plate and a panel on the new pile shoe;

step 106, a new pile leg at the bottom is lowered and locked through a pile leg bolt oil cylinder locking device of the platform, and position adjustment is carried out on the new pile shoe, so that the new pile shoe is aligned with a positioning cross mark of the new pile leg at the bottom;

and 107, driving the ship to undock, hoisting the first section of new pile leg and the second section of new pile leg through a floating crane, and welding the folding ports between the pile legs.

Specifically, the old pile leg may be sequentially divided into a first old pile leg, a second old pile leg and a bottom old pile leg according to a preset rule, where the second old pile leg is connected to the bottom old pile leg, and the bottom old pile leg is a portion of the old pile leg connected to the old pile shoe.

It should be noted that the first old leg is not a specific leg, but any leg that is not connected to the bottom old leg. That is, the worker may divide the old leg into several sections of old leg according to actual needs, not just into three sections.

It should be further noted that, the preset rule is generally: the maximum height of each old pile leg is 21.55 m, and the maximum weight of each old pile leg is 240 tons.

The embodiment of the invention takes 'Hua Xianglong' as an example of wind power platform modification, and describes a pile leg replacement method of a self-elevating wind power platform. In this embodiment, four old legs are replaced, wherein the diameter of the old leg is 4.8 meters, and the total height of the old leg is 90m. In this embodiment, each old pile leg is divided into 5 segments, a first old pile leg, a second old pile leg, a third old pile leg, a fourth old pile leg and a bottom old pile leg are sequentially arranged from top to bottom, the heights of the old pile legs are sequentially 18.54 meters, 21.55 meters, 20.9 meters and 7.46 meters, old pile shoes are sleeved on the bottom old pile legs, and the heights of the old pile shoes are 3.6 meters. As shown in fig. 2, fig. 2 is a schematic view of the old pile leg structure provided by the invention.

Further, the first old pile leg is removed, and the second old pile leg and the bottom old pile leg are reserved.

In the embodiment, the first section of old pile leg, the second section of old pile leg and the third section of old pile leg are cut in sequence from top to bottom in the wharf, and the old pile legs are respectively lifted off the wharf in sections by using a 600-ton floating crane, a 350-ton crane on a ship and a 1200-ton crane. At this time, the old leg leaves the fourth old leg and the bottom old leg.

Further, the steering vessel is docked and the old shoe and the old leg at the bottom are removed. Specifically, the rest part of the old pile leg is lowered by a first preset distance through a lifting mechanism, and wood is padded between the old pile shoe bottom plate and the dock floor; fixing the rest part of the old pile leg through a bolt of the lifting mechanism, and cutting the walls of the old pile leg and the old pile shoe to enable the old pile shoe to fall off; dismantling a pile leg with a first preset length below the old pile leg at the bottom, and descending the rest part of the old pile leg by a second preset distance through a lifting mechanism; dismantling the second pile leg with preset length below the old pile leg at the bottom, and lifting the old pile leg by a third preset distance through a lifting mechanism to finish the dismantling of the old pile leg at the bottom; draining the water in the dock, and moving the old pile shoe to the dock entrance to finish the dismantling of the old pile shoe. The first preset distance, the first preset length, the second preset distance, the second preset length and the third preset distance can be determined according to practical conditions.

In the above embodiment, after the driving ship enters the dock for the first time, the old pile leg is lowered by about 1.78 meters by using the lifting mechanism, then wood is padded between the bottom plate of the old pile shoe and the dock bottom, meanwhile, the old pile leg is temporarily fixed by using the bolt of the lifting mechanism, finally, the cylinder walls of the old pile leg and the old pile shoe are cut, and the old pile shoe is directly dropped on the wood of the dock bottom after being cut. Further, the old pile leg of 1.3 meters above the old pile shoe is destructively removed by means of shredding and the like, and then the old pile leg is lowered by about 1.3 meters by utilizing a lifting mechanism; the old pile leg of 1.3 meters above the old pile shoe is destructively removed by means of shredding and the like, and then the old pile leg is lowered by about 1.3 meters by utilizing a lifting mechanism; the old pile leg of 1.26 meters above the old pile shoe is destructively removed by means of shredding and the like, the old pile leg is lifted by about 3 meters by utilizing a lifting mechanism, and the lower guide block is detected after the lower guide block is completely exposed. Further, after the dock drains, the old pile shoe is moved to the dock entrance by using a modular car in the dock, and then the old pile shoe is hoisted to the dock or the barge by using a 600 ton floating crane in sequence. At this time, the old leg leaves the fourth old leg.

Further, the ship is driven to undock, the pile fixing chamber on the second old pile leg is taken out, and the second old pile leg is removed.

In the above embodiment, after the first undocking of the pilot vessel, the pile fixing room on the old leg is lifted out using a 1200 ton crane on the vessel and then laid flat on the quay floor or barge. Further, the wire rope, hook, pin and attachments of the old boom of the 1200 ton crane are removed and then the old boom is lifted on the starboard side using a 500 ton floating crane and a 600 ton floating crane. And further, dismantling the 4 th old pile leg by adopting a 600-ton floating crane, namely, dismantling the old pile leg.

Further, the driving ship is docked, docking blocks are arranged according to a preset drawing, new pile shoes are placed on the temporary docking blocks, and crescent plates and panels on the new pile shoes are installed.

In the above embodiment, when the ship is driven to dock for the second time, the combined pier with the height of 2.45 meters is adopted at the bottom of the ship, the dock blocks are not arranged below the new pile shoe, and the periphery of the new pile shoe and the region of the ship bow are strictly arranged according to the position and the height required by the pier arranging drawing. After the piers are discharged, quality inspection QC and shipwreck are required to be checked. When the ship is docked and the piers are arranged, the new pile shoe displacement route area is not arranged with the docking blocks, and the piers are arranged after the new pile shoe is moved in place; each new pile shoe needs to be placed at the dock bottom in a way of being offset to the broadside by 0.9 m. The pier arranging drawing and the new pile shoe shifting route can be determined according to specific conditions in the dock. Further, 4 new pile shoes are hoisted to the bottom of a dock by using a 600-ton floating crane, then the 4 new pile shoes are moved to the lower part (0.6 m on the side of the starboard) of the leg circumference of the bottom of the ship by using a module car, and then the new pile shoes are placed on temporary dock blocks by using a hydraulic positioning machine. Specifically, when the ship is docked, the draft is about 5.0 meters, the highest point at the top of the new pile shoe is 4.912m away from the dock bottom, the stern is advanced, the bow is about 10.725 meters away from the dock gate, the port is about 7 meters away from the dock wall, the starboard is about 16 meters away from the dock wall, the new pile shoe protrudes from the dock bottom by 2.1m after being retracted, and the protruding broadside is 1.35m. Further, after the ship is docked in the docking station, a crescent plate and a panel on the pile shoe are installed, flaw detection is performed after welding, and if the flaw detection is correct, a positioning guide wharf is installed at the rice-shaped position of the pile leg.

Further, the novel pile shoe is aligned with the positioning cross mark of the novel pile leg at the bottom by the locking device of the bolt oil cylinder of the pile leg of the platform, lowering and locking the novel pile leg at the bottom and adjusting the position of the novel pile shoe.

In the above embodiment, after the bottom new leg 1375 mm (i.e., 3 cm from the closing opening) is slowly lowered by the platform leg latch cylinder locking device, the lowering is stopped and the bottom new leg is locked again by the platform leg latch cylinder locking device. Further, the bottom new pile leg is locked on the locking device of the pile leg bolt cylinder of the platform, the fifth section of new pile leg is used for positioning a pile shoe segment by a foundation section, four positioning machine devices are arranged on the new pile shoe segment, the new pile shoe is aligned with a pile leg positioning cross mark by moving and adjusting the new pile shoe left and right, and then the positioning machine devices are used for adjusting up and down, so that the requirement of 200 mm of a new pile shoe and new pile leg two-folding inspection line is met, the distance between a detected quantity of a new pile shoe surrounding well structure and the new pile shoe is 150 mm, the distance between the detected quantity of the new pile shoe surrounding well structure and the new pile shoe is 2100 mm from a ship bottom baseline and 1350 mm from a shipside. Further, quality inspection QC, shipper and ship inspection are carried out on the precision positioning report, welding is carried out according to the 'new pile shoe installation welding process' after the precision positioning report is qualified, and flaw detection is carried out after welding. The new pile leg comprises a first section of new pile leg, a second section of new pile leg, a third section of new pile leg, a fourth section of new pile leg, a fifth section of new pile leg and a bottom new pile leg.

Further, the ship is driven to undock, the first section of new pile leg and the second section of new pile leg are hoisted through the floating crane, and the folding openings between the pile legs are welded. Specifically, after a second section of new pile leg is lifted by a floating crane for a fourth preset distance, checking a lifting hook, a signal and a control device of the floating crane, and checking lifting lugs and structures of the second section of new pile leg; after the second section of new pile leg is erected, removing hanging rings at the lower end of the second section of new pile leg; lifting the second new pile leg by the floating crane, and moving the second new pile leg to a platform lifting position; and adjusting the front-back left-right direction of the second section of new pile leg and the direction of the sectional positioning tool, and putting the second section of new pile leg into the pile leg total section positioning tool. Further, flaw detection work is carried out on the welding part, and platform pile insertion is carried out after the welding part is qualified.

In the above embodiment, after the second docking of the ship, the fifth section of new pile leg is vertically placed at the dock, after the fifth section of new pile leg is lifted by a 1200-ton floating crane to a height of 200 mm, the ship is stationary for 5 minutes, whether abnormal conditions exist in a lifting hook, a signal, a control device and the like of the floating crane are checked, whether obvious deformation conditions exist in lifting lugs and structures of the fifth section of new pile leg are checked, and after the checking conditions meet the requirements, the fifth section of new pile leg is erected by utilizing the cooperation of a large hook and a small hook of the floating crane. Further, after the fifth section of new pile leg is erected, the lower end hanging ring of the fifth section of new pile leg is removed, the fifth section of new pile leg is lifted after the hanging ring is removed, the floating crane lifts the fifth section of new pile leg to a platform lifting position, and when the upper end of the fifth section of new pile leg is arranged, the front-back left-right direction of the pile leg, the direction of the sectional positioning tool and the direction of the pile leg are adjusted, and then the pile leg is slowly lowered into the pile leg total section positioning tool. Further, welding the folding openings of the fifth section of new pile leg and the bottom new pile leg, and performing flaw detection; and installing the first section of new pile leg, the second section of new pile leg, the third section of new pile leg and the fourth section of new pile leg through the same steps. Further, the port side of the platform is close to a wharf pile, the pile is inserted into the mud at 6 meters, the draft is 9 meters, and the pile leg below the water surface is 15 meters.

Because the hanging ring is arranged on the outer side of the pile leg, the possibility of collision with the clindamycin hanging platform exists, and therefore, the hanging ring can be removed after being erected, and collision can be avoided.

Further, before dividing the old pile leg into the first old pile leg, the second old pile leg and the bottom old pile leg according to a preset rule, the method further comprises: prefabricating new pile legs in sections to obtain a first section of new pile legs and a second section of new pile legs; and integrally prefabricating the new pile shoe and the bottom pile leg. Specifically, the segmented prefabricated new leg comprises: manufacturing a single-section pile leg; and (5) lengthening the two single-section pile legs, and then assembling the multi-section cylinder. The process of assembling the multi-section cylinder body comprises the following steps: positioning a reference cylinder upper tire, positioning the cylinder in a sectional butt joint mode, assembling a barrel sectional annular seam, welding the annular seam, detecting the annular seam, measuring the precision after welding, installing an outfitting piece and coating the pile leg in a sectional mode. Prefabricating a new pile shoe comprising: carrying out integral prefabrication on the new pile shoe according to the bottom of the new pile leg; and synchronously installing a sacrificial anode, a pile punching system and outfitting pieces when a new pile shoe is prefabricated.

As shown in fig. 3, fig. 3 is a schematic diagram of a new pile leg segment prefabrication step provided by the invention. In the above embodiment, the prefabricated 4 new piles have a diameter of 4.8 meters, each new pile has a total height of 105.38 meters, the 100.88 meters of the upper portion of the new pile is divided into 5 segments, which are respectively a first new pile leg, a second new pile leg, a third new pile leg, a fourth new pile leg and a fifth new pile leg from top to bottom, and the heights are respectively 15.67 meters, 22 meters, 20 meters and 23.21 meters. The second section of new pile leg, the third section of new pile leg, the fourth section of new pile leg and the fifth section of new pile leg are obtained through prefabrication, and the first section of new pile leg is used repeatedly. Typically, the maximum height of a single segmented leg is about 28 meters and the maximum weight of a single segmented leg is about 322.4 tons. The height of the new pile leg at the bottom is 4.5 meters, the new pile leg at the bottom and the new pile shoe are integrally prefabricated, the new pile leg at the bottom is hoisted at a wharf, and the new pile shoe is installed in a dock. As shown in fig. 4, fig. 4 is a schematic view of a new pile leg structure provided by the invention.

In the embodiment, when a new pile leg is prefabricated, a single cylindrical section is firstly manufactured, and a sleeve is laid out according to the circumferential length (pitch diameter) of the cylindrical body and a theoretical length is expanded, and 3.1416 is obtained in pi mode. Further, drawing a processing datum line, cutting lines, checking lines (100 mm from a clean line), spraying and drawing rolling edge lines (rolling radius and radian) at two ends on a structural surface (inner side) of the steel plate, drawing 100MARK checking lines and sample punching point MARKs on upper and lower openings of an outer skin of the steel plate, marking information such as upper/lower openings of a cylinder body, pile leg numbers and the like, and meanwhile, marking the form of a bevel on the plate edge clearly. Further, the part adopts semi-automatic blanking, and blanking precision is required to be within +/-2 mm in length deviation and +/-1 mm in width deviation and +/-2 mm in diagonal deviation.

Further, the preheating temperature is confirmed by an inspector to be capable of cutting at the rear, rust spots, greasy dirt and other impurities in the range of 50 mm of the cutting edge are removed before the steel plate is cut, and slag, splashes and the like are removed after the steel plate is cut; when cutting, a semi-automatic cutting machine is selected, and neutral flame cutting is adopted; after the groove is formed, checking that the roughness of the gas cutting surface is not more than 25 microns, and no defects such as burrs, tearing, cracks and the like affecting the quality and strength of the welding seam are generated.

Further, the end is rolled, and a pressure head bisector is drawn: the bisector spacing ranges from 100 to 120 millimeters; the length of the pressing head is not less than 1000 mm. Further, checking and aligning the upper die and the lower die, wherein the longitudinal parallelism error of the upper die and the lower die is less than or equal to 1.0 millimeter; the roughness Ra of the working surface of the lower die is less than or equal to 3.2; the pressing head is carried out on a 10000 ton press, the R shape is checked by using a pressing template at any time in the pressing head process, and the control gap is not more than 1.0 mm; and if the pressure test detection indentation depth is not more than 0.8 mm, a softer material is padded on the upper die and the lower die so as to reduce the indentation depth. Further, the indenter margin is cut off: after the two ends of 10000 tons of oil press are rolled, the allowance of the two ends is cut off after the outer skin is 100 mm away from the upper end and the lower end, and a butt submerged arc welding groove of a longitudinal seam and a circular seam is formed.

Further, the steel plate is rolled into a circle, the steel plate is centered and fed into a three-roller plate bending machine, and two ends in the length direction are respectively and accurately positioned on a roller bed. The precision requirement after processing is as follows: a) Diameter (outer diameter) tolerance of 4800+2/-3 millimeters; b) The ovality tolerance is less than or equal to 6 millimeters; c) The straightness tolerance is less than or equal to 1 millimeter; d) The end part coplanarity tolerance is less than or equal to 1 millimeter; and measuring the circumference of the upper opening and the lower opening of the outer skin of the cylinder body after the rolling circle, and controlling the error by L+/-5 millimeters, wherein L is a standard value of the circumference of the outer skin uniformly regulated after the rolling circle and welding trial production. And further, positioning, assembling and welding the longitudinal joints according to a spud leg positioning and welding process.

Further, longitudinal seam welding, namely hoisting a single-section cylinder body to a simple jig frame through a hoisting belt to perform (cylinder longitudinal seam) welding, adopting carbon dioxide welding and submerged arc automatic welding for the longitudinal seam of the cylinder body, reversely buckling the back of the welding seam, hoisting the cylinder body to a roller jig frame, and performing construction according to a pile leg welding process.

Further, two sections of cylinders are lengthened, then the whole assembly of the multi-section cylinders is carried out, and finally 4 new pile leg sections with the length of 10 meters are manufactured.

Wherein, two sections barrel extension assembly requirement is: and positioning the joint line on the outer skin of the cylinder, and measuring the length of the two cylinders after lengthening, wherein the assembly length is the theoretical length. And then the annular seam is assembled and fixed, and the longitudinal seam of the adjacent cylinder is staggered by 180 degrees when the cylinder is lengthened.

Further, the lengthening of the two cylinder sections is carried out on the roller tire frame, the positioning reference is that the center line through straightness deviation of the two cylinder sections is smaller than 1 millimeter (reflected by the straightness of the four bisectors of the outer skin), and the distance between 100 lines is 200+/-1 millimeter. Checking the lengthening precision according to the meter template, and carrying out order-switching welding after confirming and submitting the lengthening precision to the shipper for recording.

Further, the requirements of the cylinder lengthening welding process are as follows: carbon dioxide gas shielded welding or submerged arc welding is adopted for bottoming the inner side of the girth weld with the extension of the cylinder; the other welding seams are filled with covers by submerged arc welding, the covers are manufactured on the roller tire frames, the two sides of the welding seams are required to be heated before welding, and the preheating temperature is 110-150 ℃; before formal welding, the performance of the welding machine is tested under the roller tire frame and the technological parameters are adjusted. And (3) prohibiting the test plate from being placed on the cylinder, adjusting parameters well, adjusting the rotating speed of the roller jig frame according to the welding speed, and adjusting the test plate and the roller jig frame to be matched and then formally welding.

Further, the multi-section barrel assembly process is as follows: positioning a reference cylinder upper tire, positioning the cylinder in a sectional butt joint mode, assembling a barrel sectional annular seam, welding the annular seam, detecting the annular seam, measuring the precision after welding, installing an outfitting piece and coating the pile leg in a sectional mode.

And further, transferring the two sections of cylinders which are finished to be lengthened to a tire frame or a roller tire frame manufactured by the outer field pile leg in a segmented mode.

Further, the pile leg cylinder body is assembled, the positioning standard is that the through straightness deviation of the center lines of the two cylinder sections is less than 1 millimeter (reflected by the straightness of the four bisectors of the outer skins), the distance between 100 lines is 200+/-1 millimeter, and the height error of the outer skins (single sides) of the adjacent cylinder bodies is less than or equal to 1 millimeter. Further, the inter-segment circular seam is constructed according to the welding process of the cylinder body (1+1/2+1), and after the circular seam flaw detection is qualified, the remainder Gao Moping and Yu Gaoxiao of the outer skin is equal to or less than 1 millimeter. Wherein, the post-welding precision requirement is: diameter tolerance 4800+2/-3 millimeters; the straightness error in the range of 19.5 meters of any pile length should not exceed 5 millimeters.

Further, 4 new pile shoes are prefabricated, the length, width and height of each new pile shoe are 14.65 meters, 12.45 meters and 4.8 meters respectively, and the weight of each new pile shoe is about 404 tons. And synchronously installing a sacrificial anode, a pile punching system, outfitting parts and the like in the prefabrication stage of the new pile shoe. And after the prefabrication of the new pile shoe is completed, performing precision measurement, weld appearance inspection, flaw detection, cabin tightness test and the like. And (5) after the new pile shoe is prefabricated and tested, the whole pile shoe is coated.

According to the pile leg replacement method for the self-elevating wind power platform, old pile legs are divided into a first old pile leg, a second old pile leg and a bottom old pile leg; removing the first old pile leg; driving the ship to dock, and removing old pile shoes and old pile legs at the bottom; the ship is driven to undock, a pile fixing chamber on the second old pile leg is taken out, and the second old pile leg is removed; docking a driving ship, discharging a docking block according to a preset drawing, placing a new pile shoe on the temporary docking block, and installing a crescent plate and a panel on the new pile shoe; the novel pile shoe is subjected to position adjustment by a platform pile leg bolt oil cylinder locking device, and the novel pile leg at the bottom is lowered and locked; and (3) the ship is driven to be undocked, the first section of new pile leg and the second section of new pile leg are hoisted through a floating crane, and the folding ports between the pile legs are welded.

The pile leg replacement method for the self-elevating wind power platform has the following advantages: the old pile leg is removed in a segmented mode, and the new pile leg is installed in a segmented mode, so that requirements on a crane are reduced; different parts of the old pile leg are removed in different modes, so that the removal efficiency of the old pile leg is improved; the novel pile leg at the bottom is locked by the locking device of the pile leg bolt oil cylinder of the platform, so that the installation precision is improved; after the old pile leg of the first section is removed, namely the old pile shoe is removed and transferred in the dock, and finally the old pile leg of the second section is removed, so that the safety is ensured.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (8)

1. The method for replacing the pile leg of the self-elevating wind power platform is characterized by comprising the following steps of:

dividing old pile legs into a first old pile leg section, a second old pile leg section and a bottom old pile leg section in sequence according to a preset rule; the bottom old pile leg is a part of the old pile leg connected with the old pile shoe;

removing the first old pile leg;

docking the ship, and removing the old pile shoe and the old pile leg at the bottom;

the ship is driven to undock, a pile fixing chamber on the second old pile leg is taken out, and the second old pile leg is removed;

docking a driving ship, discharging a docking block according to a preset drawing, placing a new pile shoe on the temporary docking block, and installing a crescent plate and a panel on the new pile shoe;

the novel pile shoe is aligned with the positioning cross mark of the novel pile leg at the bottom by the locking device of the bolt oil cylinder of the pile leg of the platform, and the novel pile shoe is subjected to position adjustment;

and (3) the ship is driven to be undocked, the first section of new pile leg and the second section of new pile leg are hoisted through a floating crane, and the folding ports between the pile legs are welded.

2. The method of replacing a pile leg of a self-elevating wind power platform according to claim 1, wherein said removing said old pile shoe and said bottom old pile leg comprises:

lowering the rest part of the old pile leg by a first preset distance through a lifting mechanism, and filling wood between the old pile shoe bottom plate and the dock floor;

fixing the rest part of the old pile leg through a bolt of the lifting mechanism, and cutting the old pile leg and the cylinder wall of the old pile shoe to enable the old pile shoe to fall off;

removing the pile leg with the first preset length below the old pile leg at the bottom, and lowering the rest part of the old pile leg by a second preset distance through the lifting mechanism;

dismantling a second pile leg with a preset length below the old pile leg at the bottom, and lifting the old pile leg by a third preset distance through the lifting mechanism to finish the dismantling of the old pile leg at the bottom;

draining the water in the dock, and moving the old pile shoe to a dock entrance to finish the dismantling of the old pile shoe.

3. The method for replacing a pile leg of a self-elevating wind power platform according to claim 1, wherein the hoisting the second new pile leg by a floating crane comprises:

after a second new pile leg is lifted for a fourth preset distance through the floating crane, checking a lifting hook, a signal and a control device of the floating crane, and checking lifting lugs and structures of the second new pile leg;

after the second section of new pile leg is erected, removing hanging rings at the lower end of the second section of new pile leg;

lifting the second section of new pile leg through a floating crane, and moving the second section of new pile leg to a platform lifting position;

and adjusting the front-back left-right direction of the second section of new pile leg and the direction of the sectional positioning tool, and lowering the second section of new pile leg into the pile leg total section positioning tool.

4. The method for replacing pile legs of a self-elevating wind power platform according to claim 1, further comprising, after welding the folding openings between the pile legs:

flaw detection is carried out on the welding part;

and performing platform pile insertion.

5. The method for replacing pile legs of a self-elevating wind power platform according to claim 1, further comprising, before dividing old pile legs into a first old pile leg, a second old pile leg and a bottom old pile leg in order according to a preset rule:

prefabricating new pile legs in sections to obtain a first section of new pile legs and a second section of new pile legs;

and integrally prefabricating the new pile shoe and the bottom pile leg.

6. The method for replacing a pile leg of a self-elevating wind power platform according to claim 5, wherein the step of prefabricating a new pile leg in sections comprises:

manufacturing a single-section pile leg;

and (5) lengthening the two single-section pile legs, and then assembling the multi-section cylinder.

7. The method for replacing pile legs of a self-elevating wind power platform according to claim 6, wherein the process of assembling the multi-section cylinder comprises: positioning a reference cylinder upper tire, positioning the cylinder in a sectional butt joint mode, assembling a barrel sectional annular seam, welding the annular seam, detecting the annular seam, measuring the precision after welding, installing an outfitting piece and coating the pile leg in a sectional mode.

8. The method for replacing a pile leg of a self-elevating wind power platform according to claim 5, wherein the prefabricated new pile shoe comprises:

and synchronously installing a sacrificial anode, a pile punching system and an outfitting piece when the new pile shoe is prefabricated.