JPH047771B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to an elevating device for a work barge, etc., and more specifically, the present invention relates to an elevating device for a work barge, etc., and more specifically, when carrying out offshore construction etc., the work barge, etc. is moved to a predetermined position at sea in order to ensure a stable working posture. This relates to a lifting device used to raise and fix the work barge to a position, and then lower the work barge and return it to the sea surface after the work is completed. [Prior art] In order to construct a sea berth, which serves as a distribution base for the purpose of storage management and receiving and receiving operations for LPG, petroleum, chemicals, etc., a work barge is used to construct a sea berth, for example, according to Foundation piles are driven under the seabed using a construction method such as 1982-213918. At that time, it is necessary to raise the work barge to a predetermined position above the sea surface or lower it to the sea surface depending on the work. In such cases, lifting devices for raising and lowering the work barge have conventionally been used that have legs that have been specially processed, such as a type with tooth-shaped legs, a type with rubber legs, etc. There were types that used materials with a high coefficient of friction, such as , and types that had wedges attached to the legs. The gripping devices corresponding to the legs have different types and shapes depending on the shape of the legs, and hold the legs using engagement force, frictional force, etc. [Problems to be Solved by the Invention] However, in the above-mentioned conventional lifting device, the legs are subjected to special processing, which results in high processing costs, and extra protrusions etc. cause the legs to descend suddenly. I couldn't. Grasping devices adapted to the legs are required to have various shapes and types corresponding to the shapes of the legs, and therefore cannot be standardized and uniformly mass-produced, which is also economically undesirable. Other conventional technologies include
The publication describes a technique for holding pillars using holding hardware on a floating work platform, and
Publication No. 18767 shows a self-lifting platform with a lifting device equipped with a load measuring device. However, in these conventional techniques, a locking mechanism is not provided on the column or the means for holding the legs. Further, the holding metal fitting disclosed in Japanese Patent Publication No. 55-35527 required operating a plurality of pistons to hold and move the column material, and was very complicated. Further, Japanese Patent Publication No. 51-49121 discloses an elevating device that moves a column up and down using a pair of upper and lower outer circumferential tapered rings. However, such known technology uses a plurality of inner circumferential wedges to secure the outer circumferential tapered ring to the column, which requires a plurality of sub-cylinders. Therefore, the hydraulic circuit inevitably becomes complicated, and the operation time becomes longer because a plurality of cylinders are operated. [Problems to be Solved] Therefore, the object of the present invention is to provide a device that can be gripped sufficiently with a relatively simple device without special processing on the legs, and can quickly raise and lower a work barge. It is to provide lifting equipment that can be used. [Means for Solving the Problems] According to the present invention, there are provided a tubular leg, an annular grasping device that grasps and holds the leg by tightening and deforming the leg, and preventing a decrease in the grasping force of the grasping device. and a load measuring device that measures the load applied to the legs. an annular holding frame and a working frame attached to the frame, the legs extending through the base frame, the holding frame and the working frame, and the holding frame and the working frame having a plurality of sectors; , a hinge-like hinge and a hinge pin that connect the sectors, and a catching cylinder that connects the sectors located at both ends. [Operation] Therefore, the working barge can be raised and lowered relative to the legs by relatively displacing the working frame and the holding frame in a known manner in a so-called inchworm manner. When gripping the working frame and holding frame, the catching cylinder is contracted and tightened. In this case, the plurality of hinged sectors can tighten the entire circumference of the leg with a substantially uniform force. In the case of a work barge, the legs must be held for a relatively long period of time to perform piling work and the like. However, in the hydraulic circuit, in order to apply a predetermined pressure for a long time due to leakage or the like, it is necessary to constantly supply pressurized fluid to the cylinder. Since this wastes energy, in order to prevent the piston rod of the catching cylinder from moving, it is also possible to engage the piston rod in the cylinder with a nut. Therefore,
The gripping device can obtain reliable gripping force over a long period of time. As described above, according to the present invention, since the gripping force of the legs is reliable, the legs can be made of standardized and mass-produced ordinary steel pipes or other tubular members. The cost and the processing cost of the grasping device for tightening the legs can be significantly reduced. Further, since the gripping device deforms by tightening the tubular leg, the leg can be reliably gripped by both the frictional force and the residual stress caused by the deformation. Further, after the work barge has risen to a predetermined position above the sea surface, the mechanical locking device prevents the gripping force of the gripping device from decreasing for a long period of time, so that work safety is guaranteed. In addition, load measuring devices measure the load on the legs, so preload loads are accurately recognized and changes in load on the platform are easily understood, improving work safety and efficiency. is achieved. In addition, in each of the grasping devices used in the invention, only one cylinder needs to be actuated for grasping and releasing the legs;
Furthermore, since locking is easily performed, the work is greatly simplified. [Embodiment] An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, a plurality of lifting devices 2-5 are provided on the upper surface of the work barge 1 floating on the sea surface 47, and the lifting devices 2-5 are placed at well-balanced positions suitable for work. It is installed in In addition, 6 in FIG. 1 is a leg, and 48 shows the seabed. The lifting device, shown in detail in FIGS. 2A and 2B, first lowers the legs 6 to the seabed 48 (FIG. 1). After the landing gear 6 has descended to the seabed 48, if the lifting device continues to lower the landing gear 6, the work barge 1 will
rises above sea level 47. The work barge 1 that has risen to a certain level above the sea level 47 is fixed and maintained at that level. After the work is completed, to return the work barge 1 to its initial state, that is, to the state where it floats above the sea surface 47, the lift device 2-5 is operated in the opposite manner to lowering the legs 6, and the work platform is What is necessary is to return the ship 1 to the sea surface 47 and then lift the legs 6 from the seabed 48. In the lifting device shown in FIGS. 2A and 2B, a bracket 7 provided on the upper surface of the work barge 1
A column 11 is attached to the column by a joint pin 8. A base frame 16 is attached to the upper end of this column by nuts 15 and 17, and a holding frame 20 is attached to the base frame 16 by tie rods 19. A working frame 21 is attached by a working cylinder 12. The holding frame 20 and the working frame 21 together constitute an annular grasping device,
The grasping device includes catching cylinders 13, 10.
(The grasping mechanism of the grasping device will be described later). The legs 6 extend through the base frame 16, the holding frame 20, and the working frame 21, and are structured to be able to move up and down by passing through them from the upper part of the lifting device 2-5 to the lower part of the work barge 1. . The sequence of operations for lowering or raising the legs 6 will be explained below. Here, the working frame 21 and the holding frame 20 each tighten and grip the legs 6 by the tightening operation (contraction stroke) of the catching cylinders 10, 13, and the loosening operation (extension stroke) of the catching cylinders 10, 13. ) to open the legs 6. (1) The state in which the working frame 21 is pulled upward by the working cylinder 12 (third
In Fig. A), the working frame 21 and the holding frame 20 are gripping the legs 6 because the catching cylinders 13 and 10 provided thereon are contracting, that is, performing a tightening operation. . (2) Extend the catching cylinder 13 of the holding frame 20 to release the holding frame 20 from grasping the leg 6, and move the working cylinder 12 downward to move the working frame 21 (while grasping the leg 6) move downward. Then, the legs 6 grasped by the working frame 21 are lowered downward, and the working frame 21 is lowered until the stroke of the working cylinder 12 reaches its lowest position, that is, until the cylinder 12 is fully extended.
Figure B). (3) When the working cylinder 12 is extended and the working frame 21 is completely lowered, the extension operation of the working cylinder is stopped. Then, the catching cylinder 13 of the holding frame 20 is contracted to a tightened state, and the leg 6 is gripped by the holding frame 20. (4) While holding the leg 6 with the holding frame 20, extend and loosen the catching cylinder 10 of the working frame 21 to release the portion of the leg 6 that was held by the working frame 21. Then, the working cylinder 12 is contracted and moved upward, the working frame 21 is moved upward, and the working frame 21 is pulled up until the working cylinder 12 is completely contracted and its stroke reaches its highest position. (5) When the working frame 21 is raised to the highest position, the contraction operation of the working cylinder 12 is stopped. Next, the catching cylinder 10 of the working frame 21 is contracted to tighten the leg 6, so that the working frame 21 grasps the leg 6. Thereafter, the operations from (1) to (5) are repeated, and the legs 6 are successively lowered into the sea until the legs 6 reach the seabed. (6) After the landing gear 6 reaches the seabed 48, perform the operations (1) to
When (5) is repeated, the work barge 1 rises from the sea surface 47 due to the reaction force (reaction) applied from the sea bed 48 to the leg 6. When the work barge 1 rises above sea level 47,
The direction of the force applied to each part of the leg 6 and the lifting device 2-5 is opposite to that during the operation of lowering the leg 6 to the seabed 48. In the case of lowering the legs, the direction of the force is in the direction of arrow
This is the direction of arrow Y in the figure. (7) In the process of transmitting force in the direction of arrow Y in FIG. acting on the base frame 16
In other words, the force applied to the support column 11 can be measured. By integrating the forces applied to each of the four columns 11, 11, 11, 11, the load on one of the legs 6 can be determined, so it is also possible to know the force applied to each leg 6 or the entire lifting device 2-5. This allows important data to be obtained in order to proceed with the work safely and quickly (the mechanism of the load measuring jack will be described later). (8) The above-mentioned operation (1) of lifting work of work barge 1
- Repeat steps (5) several times to bring the work barge 1 to sea level 47.
When the lifting to the upper predetermined position is completed, the catching cylinders 13 and 10 of the holding frame 20 and the working frame 21 are contracted and tightened, and the legs 6 are completely moved by the holding frame 20 and the working frame 21. grasp. After that, when carrying out the required work for a long time with the work barge 1 lifted above the sea surface 47, oil leakage occurs in the catching cylinders 10 and 13, and it is necessary to tighten and grasp the legs 6. It is expected that a drop in hydraulic pressure will occur, making it impossible to secure gripping force. To prevent this, the catching cylinders 10 and 13
Lock nuts 9 and 14 (second
Figure A: The details of the structure and mechanism will be described later) are tightened to ensure the gripping force of the gripping device (frames 20, 21) by the mechanical structure. (9) The required work is completed with the work barge 1 lifted above the sea level 47, and the work barge 1 is raised to the sea level 47.
When performing restoration work to return to 7, lock nuts 9 and 1 of catching cylinders 10 and 13.
4, and repeat the operations (1) to (5) in reverse to lower the work barge 1 to the sea level 47. (10) After lowering the work barge 1 to the sea level 47, the next step is to pull up the legs 6 from the sea bed 48. This is also done by repeating the reverse operations of the above (1) to (5), and when the leg 6 is pulled up to the specified position, the lock nuts 9 and 14 of the catching cylinders 10 and 13 are tightened. Tighten it to ensure gripping force for a long time. Next, the tubular legs 6 made of steel pipes or the like, the annular gripping devices 20, 21, the gripping force holding mechanisms 9, 14, and the load measuring device 17, which are characteristics of the present invention and the above embodiments, will be described in detail. (a) Legs made of steel pipes 6 In the conventional method, most of the legs for fixing the work barge 1 etc. on the sea surface 47 are made by applying special processing to the legs, and the processing cost is expensive. It is something. The lifting device of the present invention has a structure in which the legs 6 can be made of standard steel pipes or similar materials, so the processing cost of the legs 6 is low and very economical. . (b) Annular grasping device (frames 20, 21) As shown in FIGS. 6A and 6B, a plurality of sectors 22 to 25 are connected to hinges 26 to 2.
8 and hinge pins 29 to 31, and the hinges 22 and 25 are connected by a catching cylinder 33 to form an annular grasping device (indicated by arrow B in FIG. 6). When the catching cylinder 33 is operated in this state, when the piston rod 34 of the capturing cylinder 33 is operated in the extension direction (arrow α), the sector 2
The overall circumferential length of 2 to 25 increases and the diameter D of the grasping device B increases. Next, piston rod 34
When actuated in the retracting direction (arrow β), the diameter D of the gripping device B becomes smaller. A steel pipe C having an outer diameter of a diameter midway between the large and small values of the diameter D caused by the expansion and contraction of the piston rod 34 of the catching cylinder 33 is inserted into the inner diameter of the grasping device B, and the catching is carried out. When the cylinder 33 is actuated to cause the piston rod 34 to expand and contract, it is possible to grasp or release the steel pipe. With this method, the steel pipe can be grasped and opened easily, quickly, and reliably, so that the speed of the series of operations described in (1) to (5) above can be accelerated. Here, in order to strengthen the gripping force of the gripping device B on the steel pipe C, the inner diameter (inner surface) of the gripping device B is
That is, a special tooth profile may be machined on the portion that contacts the outer periphery of the steel pipe C to improve the gripping ability and obtain a stable gripping force. (c) Grasping force retention mechanism (locking device) The device disclosed in this application is capable of gripping and releasing the steel pipe (leg) by the gripping device, and thereby (alternately) pulling up and lowering the gripping device. The work is repeated. and steel pipe (legs)
An important point is to have a clear understanding of the The gripping force of the annular gripping device B (shown in Fig. 6) is generated by the tightening force of the catching cylinder 33, so in order to maintain the gripping force, the hydraulic pressure of the catching cylinder 33 must be maintained. Is required. In order to maintain the hydraulic pressure, the hydraulic chamber A (7th
In order to maintain the oil pressure shown in the figure at a constant pressure, it is necessary that oil pressure is constantly sent from the pump. In the unlikely event that the pump or the like stops, the oil pressure in the hydraulic chamber A will immediately drop, making it impossible to secure enough gripping force to reliably grip the legs. In order to prevent this, in the prior art, a check valve is disposed in the hydraulic circuit to prevent the oil pressure from dropping. However, since check valves generally leak a small amount of oil, they cannot maintain hydraulic pressure for a long period of time. Therefore, the present invention is devised so that the gripping force does not decrease even if the oil pressure decreases over a long period of time. The catching cylinder 33 is the seventh
It has a structure as shown in the figure, and gripping force is ensured by a clevis 36 at the bottom of the cylinder and a clevis 35 at the tip of the piston rod. When the pressure in the hydraulic chamber A of the cylinder 33 decreases, the piston rod 34 moves in the direction of arrow E in FIG. 7, and the gripping force decreases. To prevent this, a nut 37 is screwed into the thread of the piston rod 34-2, and the nut 37 prevents the piston rod 34 from moving in the direction of arrow E. Even if the pressure in hydraulic chamber A drops,
It provides a structure that does not reduce gripping power. (d) Load measuring device When raising and lowering the work barge 1 or performing prescribed work on the barge 1, it is necessary to know the load applied to each of the plurality of legs 6 (first figure). Therefore, in the present invention, as a method of measuring the load applied to each leg 6,
A device is provided for measuring the load on the support 11 of the lifting device 2-5, which serves to transmit the load on the legs 6 to the barge 1. This will be explained below with reference to FIG. Connect the support 11 to the bracket 7 on the top of the barge 1 at the bottom.
The upper part is fixed to the upper surface of the base frame 44 of the lifting device (FIG. 8) with a nut 39, and the load is transmitted to the base frame 44 by this nut 39. ing. Therefore, a special type jack 40 for load measurement is installed between the base frame 44 and the nut 39.
Measure the load on each support and use it as data during work. The load measuring jack 40 inserts a piston 41 also having a through hole into a cylinder tube 42 having a through hole to create a hydraulic chamber F, and injects oil into the hydraulic chamber F to seal it. Next, the base frame 44
At the top, a load measuring jack 40 is mounted in a manner penetrated by the support column 11, and the piston 4
Screw the nut 39 into the upper part of the support 11 to fix it. When an upward load is applied to the base frame 44 in this state, the cylinder tube 42 is pushed upward, but since the piston 41 is fixed with the nut 39 and cannot move upward, the oil in the hydraulic chamber F is compressed. This will cause the oil pressure to rise. This oil pressure value is the cylinder tube 4
It is clear that 2 is generated by the force pushed up by the base frame 44, that is, the load applied to the column. By taking out the hydraulic pressure in the hydraulic chamber F from one end 43 of the cylinder tube and measuring it with the meter 46, the load on the support column 11, that is, the load on the legs can be measured. In addition, 45 in FIG. 8 is a fixing nut attached to the lower part of the base frame 44. [Effects of the Invention] As described above, the present invention has the following excellent effects. (1) Since the gripping force is reliable, the legs can be made of standardized steel pipes and are inexpensive. (2) Since the gripping device uses hinged sectors, one cylinder can grip the entire circumference of the leg with almost uniform force. Therefore, the structure is also simple. (3) Since the piston of the catching cylinder can be locked with a nut, the gripping force can be maintained for a long time, and there is no need to apply hydraulic pressure, which is energy-saving. (4) The load measuring device allows you to quickly obtain the data you need during work, resulting in high work safety.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the location of the elevating device of the present invention installed on a work barge, etc., Figs. 2A and 2B are detailed views of the elevating device, and Fig. 3A shows the elevating device moving the working frame upwards. Figure 3B is a front view showing the working frame in a lowered state, Figure 4 is a diagram showing the direction of force when lowering the legs, and Figure 5 is a diagram showing the force when lifting. 6A is a sectional view of the annular gripping device, FIG. 6B is a bottom view thereof, FIG. 7 is a sectional view of the locking device, and FIG. 8 is a sectional view of the load measuring device. 1... Work barge, 2-5... Lifting device, 6...
Legs, 9, 14, 37... Locknut, 17, 4
0...Load measurement jack, 47...Sea level, 48...
... Seabed surface, A ... Hydraulic chamber, B ... Annular gripping device, C ... Diameter of steel pipe, D ... Diameter of gripping device,
E...Movement direction of piston rod, F...Hydraulic chamber.

Claims (1)

[Claims] 1 a tubular leg, an annular grasping device that grasps and holds the leg by tightening and deforming the leg;
The gripping device is equipped with a locking device that prevents the gripping force from decreasing, and a load measuring device that measures the load applied to the legs, and the gripping device is supported by a support that is attached to the upper surface of the work barge that is to be raised and lowered. an annular base frame, an annular holding frame and a working frame attached to the base frame, the legs extending through the base frame, the holding frame and the working frame; A work barge, etc., characterized in that the frame and working frame are equipped with a plurality of sectors, a hinge-like hinge and hinge pin that connect the sectors, and a catch cylinder that connects the sectors located at both ends. Lifting device.