Method for laying large diameter marine anchor chain using a tensioner

Abstract

The application discloses a method for laying large-diameter marine anchor chains by using a tensioner, and relates to the technical field of marine engineering anchor chain laying construction, and comprises the following steps: integrally hoisting a large-diameter marine anchor chain from a transport ship to the deck surface of a laying ship, clamping the anchor chain ring by using a first pawl wheel and a second pawl wheel, and simultaneously placing the anchor chain ring into a chain guide groove; during the laying process, the clamping force of the tensioner and the driving force of the pawl wheel are set according to the required tension of the catenary line type of the anchor chain in water; when the whole anchor chain is laid to the end, the tensioner and a crane are used for auxiliary construction at this time, after the crane is hung with a lifting rig, the telescopic oil cylinder of the tensioner simultaneously acts to move the moving box upwards. The application realizes a construction method for laying the whole large-diameter marine anchor chain, the design form of the pawl wheel and the adjustable chain guide groove can meet the marine anchor chains of different specifications and sizes within a certain range, the untwisting process before the anchor chain laying is optimized, the construction efficiency is improved, and the construction cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of marine engineering anchor chain laying technology, specifically to a method for laying large-diameter marine engineering anchor chains using a tensioner. Background Technology

[0002] Large-diameter marine anchor chains are primarily used in semi-submersible work platforms and FPSO mooring systems in marine engineering. Similarly, large-diameter marine anchor chains are also used in floating wind turbine platform mooring systems in the offshore wind power sector. Because the marine anchor chains used in these facilities are large in size and weight, with single chains ranging from hundreds to thousands of meters in length, they typically need to be cut into several sections, each laid and then connected using shackles. Currently, anchor chain laying is mainly carried out using multi-purpose workboats equipped with DP (Dependency Positioning) and double shark tongs. However, these multi-purpose workboats with DP are expensive and scarce. Furthermore, the use of these workboats for anchor chain laying during construction requires DP positioning, resulting in high fuel consumption and drastically increasing the cost of anchor chain laying. Currently, there are no other alternative construction methods. Summary of the Invention

[0003] The purpose of this invention is to provide a method for laying large-diameter marine anchor chains using a tensioner, thereby solving the aforementioned technical problems.

[0004] The objective of this invention can be achieved through the following technical solutions:

[0005] A method for laying large-diameter marine anchor chains using tensioners.

[0006] Includes the following steps:

[0007] The first step is to lift the large-diameter marine anchor chain from the transport ship to the deck surface of the ship to be laid, and use the first and second pawl wheels to hold the chain links while placing the chain links into the guide groove.

[0008] The second step is to set the clamping force of the tensioner and the driving force of the ratchet wheel according to the required tension of the catenary line shape of the anchor chain in the water during the laying process.

[0009] Third step: When the entire anchor chain is laid to the end, the tensioner and crane are used to assist in the construction. After the crane is equipped with the lifting slings, the tensioner telescopic cylinder 3 is activated at the same time to move the moving box upward.

[0010] Preferably, in the first step, the material strength and stiffness of the first and second ratchet wheels are greater than the strength and stiffness of the anchor chain, and the shaft holes of the first and second ratchet wheels are connected to the pinion shaft and the gear shaft.

[0011] Preferably, in the second step, the entry chain end and the exit chain end of the tensioner are fixedly provided with adjustable chain guide grooves, the surface of the adjustable chain guide grooves is slidably connected with first clamping blocks, the surface of the adjustable chain guide grooves at the opposite position of the first clamping blocks is slidably connected with second clamping blocks, and the surface of the first clamping blocks and the second clamping blocks is screw-connected with threaded rods.

[0012] Preferably, in the second step, the entry chain end and the exit chain end of the tensioner are fixedly provided with symmetrical chain stopping gates, the entry chain end and the exit chain end of the tensioner are fixedly provided with telescopic oil cylinders at the chain stopping gates, the output end of the telescopic oil cylinders is fixedly connected with the chain stopping gates, and the number of the telescopic oil cylinders and the chain stopping gates is four.

[0013] Preferably, in the second step, the tensioner comprises a fixed box body, the bottom end surface of the fixed box body is fixedly provided with a base, the top end surface of the base is fixedly provided with two symmetrical vertical columns, the upper end of the opposite surfaces of the two vertical columns is slidably connected with a moving box body, the upper end of the opposite surfaces of the two vertical columns is fixedly provided with a cross beam, the surface of the fixed box body is fixedly provided with a hydraulic motor, the output end of the hydraulic motor is fixedly connected with a pinion shaft, and the pinion shaft is meshingly connected with a large gear shaft.

[0014] The beneficial effects of the present application are as follows:

[0015] (1) The construction method for whole laying of large-diameter marine anchor chains is realized, and the design forms of the pawl wheels and the adjustable chain guide grooves can meet the laying of marine anchor chains of different specifications and sizes within a certain range;

[0016] (2) The untwisting process before the laying of the anchor chains is optimized, and the untwisting of the anchor chains is realized while the anchor chains enter the tensioner for laying;

[0017] (3) The technical method effectively improves the construction efficiency of the laying of the anchor chains and reduces the construction cost. Meanwhile, the hydraulic control system of the tensioner ensures the safety and reliability of the laying of the anchor chains. BRIEF DESCRIPTION OF DRAWINGS

[0018] The present application will be further described below in combination with the drawings.

[0019] Figure 1 is a whole structure schematic diagram of the present application;

[0020] Figure 2 is a first pawl wheel and a second pawl wheel structure schematic diagram of the present application;

[0021] Figure 3 is a front view and a top view structure schematic diagram of the telescopic oil cylinder and the chain stopping gate of the present application;

[0022] Figure 4is a top view and front view structural schematic diagram of the adjustable chain guide groove of the present application.

[0023] In the figure: 1, first pawl wheel; 2, second pawl wheel; 3, telescopic oil cylinder; 4, chain stopping guillotine; 5, adjustable chain guide groove; 6, first clamping block; 7, second clamping block; 8, threaded rod; 9, fixed box body; 10, base; 11, stand column; 12, moving box body; 13, cross beam; 14, anchor chain; 15, hydraulic motor; 16, pinion shaft; 17, gear shaft. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0025] Please refer to Figures 1-4 As shown in the figure, the present application is a method for laying large-diameter marine anchor chain by using a tensioner, including the following steps:

[0026] First step, the whole large-diameter marine anchor chain 14 is hoisted from the transport ship to the deck surface of the laying ship, the chain ring is clamped by the first pawl wheel 1 and the second pawl wheel 2, and at the same time, the chain ring is put into the chain guide groove. For the delivery of the anchor chain 14 at this time, the end of the anchor chain 14 can be hoisted to the side of the tensioner by the crane;

[0027] Second step, during the laying process, the clamping force of the tensioner and the driving force of the pawl wheel are set according to the required tension of the catenary line profile of the anchor chain 14 in the water. If the tension of the anchor chain 14 exceeds the limit range of the set value, the chain entry end and the chain exit end of the chain stopping device system will simultaneously open the chain stopping guillotine to fix the anchor chain, so as to prevent the anchor chain from directly sliding into the sea;

[0028] Third step, when the whole anchor chain 14 is laid to the end, the tensioner and the crane are used for auxiliary construction at this time. After the hoisting rigging is set by the crane, the telescopic oil cylinder 3 of the tensioner simultaneously moves the moving box body 12 upward. At this time, the crane must be under stress, and the anchor chain segment from the anchor chain 14 at the chain exit end position to the lifting point is not under stress. Only under this condition, the chain stopping guillotine 4 can be retracted. Then, the end of the anchor chain is put into the sea by the crane, and the whole anchor chain laying construction is completed;

[0029] In the first step, the material strength and rigidity of the first pawl wheel 1 and the second pawl wheel 2 are greater than the strength and rigidity of the anchor chain 14, the shaft holes of the first pawl wheel 1 and the second pawl wheel 2 are connected with the pinion shaft 16 and the gear shaft 17, the first pawl wheel 1 is installed in the tensioner main frame moving box, the second pawl wheel 2 is installed in the tensioner main frame fixed box, and the installation positions of the pawl wheels in the upper and lower boxes are required to be matched with each chain ring and symmetrical, and the principle of mutual meshing between similar gears is similar;

[0030] In the second step, the adjustable chain guide groove 5 is fixedly installed at the chain inlet end and the chain outlet end of the tensioner, the first clamping block 6 is slidably connected to the surface of the adjustable chain guide groove 5, the second clamping block 7 is slidably connected to the surface of the adjustable chain guide groove 5 at the opposite position of the first clamping block 6, and the threaded rods 8 are screw-connected to the surfaces of the first clamping block 6 and the second clamping block 7, so that the positions of the first clamping block 6 and the second clamping block 7 can be adjusted after the two threaded rods 8 are rotated, thereby limiting the surface of the adjustable chain guide groove 5.

[0031] In the second step, the chain stopping gate 4 is symmetrically fixedly installed at the chain inlet end and the chain outlet end of the tensioner, the telescopic oil cylinder 3 is fixedly installed at the chain inlet end and the chain outlet end of the tensioner, the output end of the telescopic oil cylinder 3 is fixedly connected with the chain stopping gate 4, the number of the telescopic oil cylinder 3 and the chain stopping gate 4 is four, the adjustable chain guide groove and the chain stopping device system are synchronously installed at the chain inlet end and the chain outlet end of the tensioner, the moving box and the fixed box of the tensioner main frame are connected through the four telescopic oil cylinders 3, the cylinder body part of the oil cylinder is connected with the fixed box, and the piston rod end is connected with the moving box, so that the up and down movement of the moving box is realized and synchronous control is achieved, and the clamping force of the anchor chain during the laying of the anchor chain is achieved.

[0032] In the second step, the tensioner comprises a fixed box 9, the bottom end surface of the fixed box 9 is fixedly installed with a base 10, the top end surface of the base 10 is symmetrically fixedly installed with two vertical columns 11, the opposite faces of the two vertical columns 11 are slidably connected with a moving box 12 at the upper end of the fixed box 9, the opposite faces of the two vertical columns 11 are fixedly installed with a cross beam 13 at the upper end of the moving box 12, the surface of the fixed box 9 is fixedly installed with a hydraulic motor 15, the output end of the hydraulic motor 15 is fixedly connected with the pinion shaft 16, and the pinion shaft 16 and the gear shaft 17 are meshingly connected.

[0033] The above describes one embodiment of the present application in detail, but the content described is only the preferred embodiment of the present application, and cannot be considered as limiting the scope of the present application. Any equivalent changes and improvements made within the scope of the present application should still belong to the patent scope of the present application.

Claims

1. A method for laying large diameter marine anchor chain by using a tensioner, characterized in that, It comprises the following steps: Step 1: The large diameter marine anchor chain (14) is lifted from the transport ship to the deck surface of the laying ship as a whole, the chain ring is clamped by the first pawl wheel (1) and the second pawl wheel (2), and the chain ring is placed in the chain guide groove; Step 2: During the laying process, the clamping force of the tensioner and the driving force of the pawl wheel are set according to the required tension of the catenary line profile of the anchor chain (14) in the water; Step 3: When the whole anchor chain (14) is laid to the end, the tensioner and the crane are used to assist the construction, after the hoist is hung, the telescopic oil cylinder (3) of the tensioner is actuated to make the moving box (12) move up; The tensioner comprises a fixed box (9), a base (10) is fixedly installed on the bottom end surface of the fixed box (9), a stand (11) is fixedly installed on the top end surface of the base (10) in a symmetrical manner, a moving box (12) is slidably connected to the upper end of the fixed box (9) on the opposite faces of the two stands (11), a cross beam (13) is fixedly installed on the upper end of the moving box (12) on the opposite faces of the two stands (11), a hydraulic motor (15) is fixedly installed on the surface of the fixed box (9), the output end of the hydraulic motor (15) is fixedly connected with a pinion shaft (16), and the pinion shaft (16) is meshingly connected with a large gear shaft (17); The shaft holes of the first pawl wheel (1) and the second pawl wheel (2) are connected with the pinion shaft (16) and the large gear shaft (17); The entry end and the exit end of the tensioner are fixedly installed with adjustable chain guide grooves (5).

2. A method of laying a large diameter marine anchor chain using a tensioner as claimed in claim 1, wherein, The material strength and rigidity of the first pawl wheel (1) and the second pawl wheel (2) are greater than the strength and rigidity of the anchor chain (14).

3. A method of laying a large diameter marine anchor chain using a tensioner as claimed in claim 1, wherein, A first clamping block (6) is slidably connected to the surface of the adjustable chain guide groove (5), a second clamping block (7) is slidably connected to the surface of the adjustable chain guide groove (5) at a position opposite to the first clamping block (6), and a threaded rod (8) is screwedly connected to the surface of the first clamping block (6) and the second clamping block (7).

4. A method of laying a large diameter marine anchor chain using a tensioner as claimed in claim 1, wherein, The entry end and the exit end of the tensioner are fixedly installed with chain stopping gates (4) in a symmetrical manner, telescopic oil cylinders (3) are fixedly installed at the entry end and the exit end of the tensioner at the chain stopping gates (4), the output end of the telescopic oil cylinder (3) is fixedly connected with the chain stopping gate (4), and the number of the telescopic oil cylinders (3) and the chain stopping gates (4) is four.

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