JP4975300B2 - Lifting method using a plurality of cranes and lifting jig used therefor - Google Patents

Description

  The present invention relates to a method for lifting a load, a structure, or the like using a plurality of cranes, and a lifting jig, and more particularly, to a method and a jig suitable for lifting a large and heavy structure.

  A crane is usually used for loading and unloading cargo at a cargo port. In addition, cranes are also used to lift structures in large-scale structure manufacturing sites, such as shipyards. There are various types of cranes, such as jib cranes, portal cranes, bridge cranes, overhead cranes, etc., and their lifting capacities vary from several tons to over 1,000 tons.

  A crane is usually used to lift one object by one. However, depending on the lifting site such as a manufacturing site, it may be required to lift a structure having a weight that exceeds the capacity of the installed crane. In response to such a request, if two cranes are installed at the lifting site, it is conceivable to lift the crane while sharing the load with these two cranes.

  For example, in theory, a structure having a weight of 1,000 tons can be lifted by two cranes having a capacity of 500 tons. However, since the two cranes are operated by different operators, when lifting one structure with two cranes, care must be taken so that there is no difference between the lifting speeds of the two cranes. This means that in the case of lifting in the above example, the load of twice the capacity will be applied to the one with the higher lifting speed, and in the case of hanging, the load twice the capacity to the one with the lower suspension speed. This is because a burden is required. For this reason, there is a work instructor who monitors the lifting state, and the operators of the two cranes each operate the crane under the instructions of the work instructor. In addition, the lifting / hanging speed or load is limited by using a signal from a lifting / hanging speed meter or a load meter installed in the crane. That is, when the lifting / hanging speed or load exceeds the limit, the crane operation is automatically stopped.

  However, in recent shipyards targeting large ships, there are cases where two or more large cranes, for example, three, are provided, but one crane is used to lift one structure. Absent. This is due to the following reason. In the following description, only the expression “lifting” is used, but the same applies to the case of hanging. In the following description, “lifting” includes the meaning of hanging.

  If one structure having a weight of 2000 tons is to be lifted by three cranes having a capacity of 700 tons, it is conceivable to adopt a lifting form as shown in FIG. In FIG. 8, two hooks 220, 320, 420 are provided on balances 210, 310, 410 connected to wires 200, 300, 400 connected to three cranes (not shown), respectively. Corresponding to these six hooks in total, the structure 100 is provided with pieces 110 at six locations, and the corresponding hooks and pieces are connected by wires. At that time, the installation location of the piece 110 needs to be determined in consideration of the shape, the center of gravity, and the like of the structure 100. However, the shape of the structure 100 is not necessarily a rectangular parallelepiped shape as shown in the figure, and usually has a complicated shape. When the shape of the structure 100 is complicated, the calculation of the center of gravity is also complicated, and the design of the installation location of the piece 110 becomes difficult.

  Now, the operators of the three cranes each operate the crane based on an instruction from a work instructor who gives an instruction while monitoring the lifting state of the structure 100. Here, during operation, for example, when the lifting speed of the central crane becomes faster than the lifting speed of the adjacent cranes, a load of 2000 tons of the structure 100 acts on the central crane (wire 300) as it is. Become. That is, a load close to three times the capacity acts on the central crane (wire 300). This value is much larger than twice that of the above two examples, and the limit cannot be dealt with, and there is a possibility that a very dangerous state such as a crane failure or wire cutting may occur.

  From this point of view, it is necessary to install a crane with a large capacity when considering large-scale shipbuilding. However, if a crane with a capacity of 2000 tons can be lifted by three cranes with a capacity of 700 tons, three cranes with a capacity of 700 tons are installed rather than a crane with a capacity of 2000 tons. This is desirable in terms of improving production efficiency. This means that even if a crane with a capacity of 2000 tons is used, the amount of time it takes to reach a full capacity is small. This is because the form that can be engaged in parallel work is far superior in terms of production efficiency.

  Then, the subject of this invention is providing the lifting method and jig | tool for it which can lift one to-be-lifted body safely with several cranes of 3 or more units | sets.

  Another object of the present invention is to enable the above-mentioned problems to be realized without using a complicated control device.

  According to the present invention, there is provided a method for lifting a body to be lifted using at least three cranes, wherein each of the at least three cranes has a body installed at each of the lifted bodies at at least two locations. Lifting with at least two wires through the hook portion, and dividing the at least three cranes into two sets so that at least one set has at least one combination of two cranes, In the combination of the two cranes, one wire of one crane and one wire of the other crane are connected via the corresponding hooked portions, respectively, and Connect the other wire and the other wire of the other crane after passing through the corresponding hooked portions. Thus, when lifting, the load received by one wire of the one crane and the load received by one wire of the other crane, the load received by the other wire of the one crane, and the other wire of the other crane There is provided a lifting method characterized in that the load received by is equivalent.

  In the present lifting method, it is preferable that the hooked portion includes a pulley on which the corresponding wire is wound.

  In the lifting method according to the present invention, each of the at least three cranes includes at least two hooks for lifting, and a plurality of wires are hung on each hook. When a plurality of sets of wire hanging pieces corresponding to the plurality of wires are respectively installed at locations corresponding to the plurality of wires, a plurality of pulleys are provided between the plurality of wires and the plurality of sets of wire hanging pieces. You may make it perform equal suspension for every said to-be-engaged part by interposing a block and hanging the wire from one pulley block around the said pulley.

  In the lifting method according to the present invention, further, between the engaged portion corresponding to one wire of the one crane and the engaged portion corresponding to one wire of the other crane, or of the one crane. If there is an obstacle that prevents the wire from extending between the hooked part corresponding to the other wire and the hooked part corresponding to the other wire of the other crane, a through hole is formed in the obstacle. It is made to pass through the wire.

  According to the present invention, there is also a lifting jig provided between the crane and the lifted body when the lifted body is lifted using at least three cranes, and each of the at least three cranes is The lifted body is lifted through hooked portions installed at each of at least two places, and at least one of the three cranes is at least one combination of two cranes. A lifting jig provided between the combination of the two cranes and the body to be lifted in a form divided into two sets so as to have, the hooked portion and the two cranes Including at least two wires per crane connected to each crane in combination and hung on the at least two hooked portions, One wire of one crane and one wire of the other crane in the combination of lanes are connected after passing through the corresponding hooked portions, and the other wire of the one crane The other wire of the other crane is connected to each other through the corresponding hooked portions, whereby the load received by one wire of the one crane and the other The lifting jig characterized in that the load received by one wire of the crane, the load received by the other wire of the one crane, and the load received by the other wire of the other crane are equivalent. Is provided.

  In the lifting jig according to the present invention, it is preferable that the hooked portion includes a pulley on which the corresponding wire is wound.

  In the lifting jig according to the present invention, each of the at least three cranes is provided with at least two lifting hooks, and a plurality of sets of wire hooks are provided at positions corresponding to the hooked portions on the lifting body. When the piece piece is installed, the lifting jig includes a plurality of wires hung on each hook so as to correspond to the plurality of sets of wire hanging pieces, the plurality of wires, and the plurality of sets. A plurality of pulley blocks provided so as to be interposed between the wire-hanging pieces of the wire and the wire from one pulley block is hung around the pulley so that the hooks are evenly suspended. Anyway.

  The lifting jig according to the present invention further comprises a pulley of the hooked portion corresponding to one wire of the one crane and a pulley of the hooked portion corresponding to one wire of the other crane. And a bar-shaped body provided with a pulley of the hooked portion corresponding to the other wire of the one crane and a pulley of the hooked portion corresponding to the other wire of the other crane. May be.

  According to the present invention, it is possible to safely lift a structure having a weight close to the sum of the respective capacities of three or more cranes without requiring improvement on the crane side including the control device. Further, when lifting, there is no influence of the shape of the structure or the position of the center of gravity.

  The principle of the lifting method according to the present invention will be described with reference to FIGS. In the lifting method according to the present invention, one structure or the like is lifted using three or more cranes, but each crane can be a normal crane that can be operated independently. That is, the feature of the lifting method according to the present invention is not on the crane side but on the lifting site side. The type of crane is not particularly limited, but a case of a portal crane will be described below. In simple terms, a portal crane can run on a rail with a gate-shaped structure, and the part to be lifted can run in a direction perpendicular to the above-mentioned traveling direction along the ceiling of the portal. It is a crane.

  In FIG. 1, three cranes (not shown) are used here, and hooks (not shown) are respectively attached to both ends of the balances 11, 21, and 31 connected to the wires 10, 20, and 30 connected to the cranes. ). That is, two places of the structure are lifted by one crane.

  Hereinafter, for convenience, the cranes for the balances 11, 21, and 31 will be referred to as a No. 1 crane, a No. 2 crane, and a No. 3 crane, respectively. Corresponding to a total of six hooks in the balances 11, 21, 31, the structure 40 is provided with pieces 40-1 to 40-6 as hooked portions at six locations, and the wires 11-1, 11-are connected from the hooks. 2, 21-1, 21-2, 31-1, 31-2 are extended and hung on the corresponding pieces. The piece is for connecting and fixing the wire and hooking, but has a hole for the wire to pass through. In this example, as in FIG. 8, three pieces 40-1 to 40-6 are provided at intervals of three pieces at positions close to the side edge along the longitudinal direction of the structure 40. The installation location and number of pieces are designed according to the shape, weight, etc. of the structure 40, but a complicated design that particularly takes the center of gravity into consideration is not necessary.

  In this example, two of the three cranes, here, the No. 2 crane and the No. 3 crane for the balance 21 and the balance 31 complement each other (load). This is realized as follows. The wires 11-1 and 11-2 from the balance 11 are fixed to the pieces 40-1 and 40-2, respectively. However, the wire 21-1 from the balance 21 is not fixed to the piece 40-3 and passes through the holes. The wire 31-1 from the balance 31 is also not connected to the piece 40-5 but connected to each other through the hole. Similarly, the wire 21-2 from the balance 21 passes through the hole without being fixed to the piece 40-4, and the wire 31-2 from the balance 31 is also connected to each other through the hole without being fixed to the piece 40-6. I am doing so. In other words, one end side of the balance 21 and the balance 31 is connected by a single wire W1 through the hole of the piece 40-3 and the hole of the piece 40-5, and the other end side of the balance 21 and the balance 31 is connected to the piece 40. -4 and the hole of the piece 40-6 are connected by another wire W2.

  According to such a lifting configuration, for example, if the No. 1 crane, the No. 2 crane, and the No. 3 crane for the balances 11, 21, and 31 each have a capacity of 800 tons (a lifting load of 700 tons), the maximum weight is 2000 tons. The structure 40 can be lifted up evenly with one third of the load. This means that between the balance 21 and the balance 31, the wire 21-1 and the wire 31-1, that is, the wire W1, can freely move through the holes of the piece 40-3 and the piece 40-5, and the wire 21-2 And the wire 31-2, that is, the wire W2 is freely movable through the holes of the piece 40-4 and the piece 40-6. That is, the combination of the piece 40-3, the piece 40-5, and the wire W1 is such that the loads acting on the wire 21-1 and the wire 31-1 are equivalent, and the piece 40-4, the piece 40-6, and the wire This is because the combination with W2 serves as an equalizer so that the loads acting on the wire 21-2 and the wire 31-2 are equivalent. Of course, the loads acting on the four wires 21-1, 21-2, 31-1, 31-2 are also equivalent.

  Due to the action of such an equalizer, even if the shape of the structure 40 is complicated or the position of the center of gravity is decentered in this lifting form, it is not significantly affected.

  Although the lifting method according to the present invention does not require that all the cranes have the same capacity, it is preferable that the two cranes used in the combination of the two have the same capacity. FIG. 2 shows another form of the lifting method according to the present invention. Here, the case where three cranes are used as described above is shown, but a lifting wire as shown in FIG. 1 is not used, and a lifting wire is directly hung on the crane hook. That is, the two wires 11-1 and 11-2 hung on the hook 13 of the No. 1 crane are connected and fixed to the pieces 40-1 and 40-2 of the structure 40. On the other hand, one of the two wires 21-1 hung on the hook 23 of the No. 2 crane passes through the hole without being fixed to the piece 40-3, and the two wires hung on the hook 33 of the No. 3 crane One of the wires 31-1 is also not connected to the piece 40-5 but connected to each other through the hole. Similarly, the other wire 21-2 of the two wires hung on the hook 23 passes through the hole without being fixed to the piece 40-4, and the other of the two wires hung on the hook 33 The wire 31-2 is not fixed to the piece 40-6 but is connected to each other through the hole. In other words, the hook 23 and the hook 33 are connected by a single wire W1 through the hole of the piece 40-3 and the hole of the piece 40-5, and the hole of the piece 40-4 and the piece 40- Connection is made with another wire W2 that passes through the six holes.

  Even with such a lifting configuration, for example, the No. 1 crane, the No. 2 crane, and the No. 3 crane can be used with different combinations of capacities such as 100 tons, 50 tons, and 50 tons, respectively. A 200-ton structure 40 can be lifted.

  1 and 2, the three cranes are divided into two sets, one set and two sets, and the two cranes in the two sets complement each other with a load (load). Used to fit. When using four or more cranes, for example, four cranes, divide them into two sets of two, and use two of each set in relation to the second and third cranes described in FIGS. Needless to say, it's okay. In this case, it is possible to lift a heavy object corresponding to the total capacity of the four cranes. In the case of 5 units, the operation of the equalizer may be realized between the 2 cranes and the 3 cranes by dividing into 2 groups and 3 groups. .

  1 and 2, it is preferable to use a pulley as a hooked portion as shown in FIG. 3 for a portion that acts as an equalizer. In FIG. 3, each of the pieces 40-3 to 40-6 is provided with pulleys P3 to P6 via support devices 41-3 to 41-6, and the wire W1 is hung around the pulley P3 and the pulley P5 on one side. Another wire W2 is hung around the pulley P4 and the pulley P6 on the other side.

  In the above-mentioned form, the wires 21-1 and 31-1 provided between the balances 21 and 31 and the pieces 40-3 to 40-6 of the structure 40, that is, the wires W1 and the pulleys P3 and P5 are provided. The combination and the combination of the wires 21-2 and 31-2, that is, the wire W 2 and the pulleys P 4 and P 6 can be collectively referred to as a lifting jig.

  FIG. 4 shows an example of a support device 41-3 provided in the piece 40-3 here as a specific example of the support device. In FIG. 4, the support device 41-3 includes two pulleys 41-34 connected via a U-shaped shackle 41-31, wires 41-32, and two support pieces 41-33 (only one is shown). , 41-35, etc. One end of the shackle 41-31 is rotatably connected to the piece 40-3, and the other end is hooked with a wire 41-32 that is hung around the pulley 41-34. A wire W1 is hung on the pulley 41-35. According to such a configuration, the height position of the pulley 41-35 is freely changed according to the pulling force of the wire W1. The other support devices 41-4 to 41-6 are exactly the same.

  The use of the support device as described above is suitable when there is an obstacle that prevents the presence of the wire in the region between two adjacent pieces in the structure, and the reason will be described with reference to FIG. .

  FIG. 5 shows a preferred specific example of the combination of the wire 21-1 and the wire 31-1 shown in FIG. 3, and in particular, the region between the piece 40-3 and the piece 40-5 in the structure 40. FIG. 2 shows a case where an obstacle BHD that prevents the presence of the wire W1 exists. In addition, for each wire, so-called uniform suspension is performed by using a total of 8 sets of pulley blocks of 4 sets on the upper side and 4 sets on the lower side. Each upper pulley block and each lower pulley block have two pulleys, an upper side and a lower side.

  In FIG. 5, four sets of upper pulley blocks UB1 to UB4 are connected to a hook 25 provided on one end side of a balance 21 (FIG. 3) of a No. 2 crane. Specifically, wires UW1 to UW4 are respectively wound around the upper pulleys in the upper pulley blocks UB1 to UB4, and these four wires UW1 to UW4 are hung on the hooks 25. On the other hand, on the structure 40 side, the piece 40-3 shown in FIG. 3 is realized by four sets, each including two sets, and a total of eight piece portions. Then, wires LW1 to LW4 are respectively wound around the lower pulleys in the four sets of lower pulley blocks LB1 to LB4, and both ends of each of the four wires are fixedly connected to the corresponding two piece parts on the lower side. Yes. However, one end (the one closer to the obstacle BHD) of the wire LW4 hung on the lower pulley in the lower pulley block LB4 closest to the obstacle BHD is not a piece part closest to the obstacle BHD, but a support device. It is hung on the pulley P3 supported by 41-3. And the support apparatus 41-3 (shackle 41-31 of FIG. 4) is connected with the piece part nearest to the obstruction BHD. Thereby, the wire LW4 hung on the pulley P3 can be regarded as the wire W1 described in FIG. Further, the obstacle BHD is provided with a through hole for passing the wire W1, and the wire W1 is passed therethrough. The height position of the through hole is matched with the height position of the wire W1 assumed when the structure 40 is lifted.

  Furthermore, one wire MW is spanned between the lower four pulleys in the upper pulley blocks UB1 to UB4 and the upper four pulleys in the lower pulley blocks LB1 to LB4. The relationship between the wire MW and each pulley of the upper pulley block and the lower pulley block will be described in detail as follows. As indicated by arrows in FIG. 5, the wire MW is connected to the upper pulley of the lower pulley block LB1—the lower pulley of the upper pulley block UB1—the upper pulley of the lower pulley block LB4—under the upper pulley block UB4. Side pulley-Upper pulley block LB3 upper pulley-Upper pulley block UB3 lower pulley-Lower pulley block LB2 upper pulley-Lower pulley block UB2 lower pulley-Lower pulley block LB1 Endless because of the relationship of the upper pulley.

  The above configuration is exactly the same in the hook 35 provided on one end of the balance 31 (FIG. 3) of the No. 3 crane. That is, one end of the wire LW4 ′ closest to the obstacle BHD is hung on the pulley P5 of the support device 41-5 and is passed through the through hole of the obstacle BHD, so that a plurality of lines from the hook 25 to the hook 35 are obtained. The wires can be collectively considered as one wire W1. And the other side of the balance 21 of the No. 2 crane and the opposite side of the balance 31 of the No. 3 crane are exactly the same as the configuration shown in FIG.

  Considering the above configuration, the upper four wires UW1 to UW4 and the lower four wires LW1 to LW4 can be regarded as one wire in one bundle of four, and the upper four pulleys It can be considered that the block and the lower four pulley blocks are also connected by one wire MW. Therefore, it can be considered that the hook 25 is connected to the lower wire LW4 by one wire (one lifting member), and it can be regarded as a lifting jig together with the hook 35 side. Moreover, the black part CN shown in the intermediate part and piece part vicinity of each wire is a connector. With these connectors CN, the lifting jig can be easily disassembled. This takes into account that it is more convenient to disassemble and carry the lifting jigs after the lifting operation is completed, and to store them. In addition, in order to pass the wire W1 through the through hole of the obstacle BHD, the wire needs to be disassembled. In any case, the materials, mechanical strength, etc. of each wire, connector, and pulley block are designed in consideration of the lifting load.

  FIG. 6 shows a modification of the configuration of FIG. This example is applied when a through hole for passing the wire W1 cannot be provided in the obstacle BHD. In FIG. 6, a pulley P3 and a pulley P5 are provided on the bar-like body 50, and the bar-like body 50 is positioned above the obstacle BHD, so that the pulley P3 and the pulley P5 and the wire W1 between them are connected. It is arranged above the obstacle BHD. Of course, without the bar-like body 50, the pulley P3 and the pulley P5 shown in FIG. 5 and the wire W1 between them may be arranged directly above the obstacle BHD.

  A lifting jig using a pulley block formed by a combination of a plurality of pulleys as shown in FIGS. 5 and 6 can also be called an equalizer, and this type of equalizer itself is provided in various types. Yes. That is, the jig | tool shown by FIG. 5, FIG. 6 is only an example of the jig | tool used for the lifting method by this invention, A various jig | tool can be used for the lifting method by this invention.

  Moreover, since each said form assumes the three portal cranes which drive | work on the same rail, the three balances 11, 21, and 31 are located in a straight line. However, when a crane other than the portal crane is used, the three balances can be arranged as shown in FIG. 7, for example. In FIG. 7, the three cranes are divided into two sets, one set and two sets, and the balances 21 ′ and 31 ′ connected to the two cranes in the two sets are connected to the structure 40. Are arranged in a direction perpendicular to the longitudinal direction. The wires 11-1 'and 11-2' from the balance 11 'are fixed to the pieces 40-1 and 40-2, respectively, but the wire 21-1' from the balance 21 'is not fixed to the piece 40-3. Through the hole, the wire 31-1 ′ from the balance 31 ′ is not fixed to the piece 40-4 and is connected to each other through the hole. Similarly, the wire 21-2 'from the balance 21' passes through the hole without being fixed to the piece 40-5, and the wire 31-2 'from the balance 31' is also not fixed to the piece 40-6. To connect with each other. That is, one end side of the balance 21 'and the balance 31' is connected by one wire W1 passing through the hole of the piece 40-3 and the hole of the piece 40-4, and the other end side of the balance 21 'and the balance 31'. Are connected by another wire W2 through the hole of the piece 40-5 and the hole of the piece 40-6.

  In any case, when one structure is lifted using three cranes, it is operated as follows. Each crane is provided with a speed meter for detecting the lifting / hanging speed and a load meter for detecting a load acting on the wire. Depending on the weight of the structure from the work instructor, the burden load of each crane is instructed. The operator of each crane operates so that the instructed burden load is obtained while looking at the load meter. Of course, the lifting / suspending speed or load is limited using a signal from a speedometer or load meter installed in the crane. When the lifting / hanging speed or load exceeds the limit, the crane operation is automatically stopped. Here, even if the lifting / hanging speed or load of one crane may exceed the limit, the load acting on this crane is the same as when two units are operated in parallel. There is no danger like the parallel operation with three units explained in the technology.

  Although the present invention has been described with respect to several preferred embodiments, the present invention is not limited to the above-described embodiments. For example, depending on the type of the body to be lifted, a lifting piece may not be provided. In such a case, for example, a wire may be hung on the suspended body, and a hook from a crane may be hung on this wire. Further, for example, the present invention can be applied even when three cranes each lift the object to be lifted at one place. That is, the load may be complemented with a single wire for two of the two sets.

  As is apparent from the above description, according to the lifting method and lifting jig of the present invention, three or more cranes can be used in cooperation to safely lift one structure. Of course, by using a normal lifting jig instead of the lifting jig according to the present invention, it is possible to engage in another work alone.

  The case where the preferred embodiment of the present invention is applied to a portal crane installed in a shipyard has been described. However, the scope of the present invention is not limited to a shipyard, and therefore the crane is also limited to a portal crane. It is not a thing. Moreover, what is lifted is not limited to a structure, and may be anything as long as it can be lifted with a wire. Furthermore, it can be applied not only to lifting a heavy structure with a large crane, but also to lifting one structure with three or more small cranes.

It is a figure for demonstrating the principle of the lifting method by this invention. It is a figure for demonstrating the modification of the lifting form of FIG. It is a figure for demonstrating preferable embodiment of the example of FIG. It is the figure which showed the specific example of the support apparatus for supporting the pulley shown by FIG. It is the figure which showed the specific example for implementing equal suspension in this invention. It is the figure which showed the modification of the example of FIG. It is a figure for demonstrating the other modification of the lifting form of FIG. It is a figure for demonstrating the lifting method considered when lifting one structure with three cranes.

Explanation of symbols

10, 20, 30, 11-1, 11-2, 21-1, 21-2, 31-1, 31-2, W1, W2, MW wire 11, 21, 31 Balance 40 Structure 40-1-40 -6 piece 41-3 to 41-6 support device P3 to P6 pulley UB1 to UB4 upper pulley block LB1 to LB4 lower pulley block BHD obstacle CN connector

Claims (8)

A method of lifting a body to be lifted using at least three cranes,
The at least three cranes each lift the suspended body with at least two wires via the hooked portions installed at the respective positions in at least two places,
Dividing the at least three cranes into two groups so that at least one set has at least one combination of two cranes;
In the combination of the two cranes, one wire of one crane and one wire of the other crane are connected via the corresponding hooked portions, respectively, and By connecting the other wire and the other wire of the other crane via the corresponding hooked portions, respectively,
When lifting, the load received by one wire of the one crane and the load received by one wire of the other crane and the load received by the other wire of the one crane and the other wire of the other crane are received. A lifting method characterized in that the load is equivalent.   The lifting method according to claim 1, wherein the hooked portion includes a pulley on which the corresponding wire is wound. The at least three cranes each include at least two lifting hooks, and a plurality of wires are hung on each hook,
In the suspended body, a plurality of sets of wire hanging pieces corresponding to the plurality of wires are installed at locations corresponding to the hooked portions,
A plurality of pulley blocks are interposed between the plurality of wires and the plurality of sets of wire-hanging pieces, and the wires from one pulley block are wound around the pulleys to equalize each hooked portion. The lifting method according to claim 2, wherein the lifting method is performed.   Between the hooked portion corresponding to one wire of the one crane and the hooked portion corresponding to one wire of the other crane, or the hooked portion corresponding to the other wire of the one crane When there is an obstacle that prevents the wire from extending between the part and the hooked part corresponding to the other wire of the other crane, a through hole is provided in the obstacle to allow the wire to pass therethrough. The lifting method according to any one of claims 1 to 3. The lifting jig is provided between the crane and the lifted body when lifting the lifted body using at least three cranes, and each of the at least three cranes has at least two lifted bodies. The at least three cranes are also divided into two groups such that at least one group has at least one combination of two cranes. A lifting jig provided between the combination of the two cranes and the body to be lifted,
The hooked portion;
Including at least two wires per crane connected to each crane in the combination of the two cranes and hung on the at least two hooked portions;
In the combination of the two cranes, one wire of one crane and one wire of the other crane are connected to each other via the corresponding hooked portions, and The other wire and the other wire of the other crane are connected via the corresponding hooked portions, respectively,
Thus, when lifting, the load received by one wire of the one crane and the load received by one wire of the other crane, the load received by the other wire of the one crane, and the other load of the other crane A lifting jig characterized in that the load received by the wire is equivalent.   The lifting jig according to claim 5, wherein the hooked portion includes a pulley on which the wire corresponding to the hooked portion is wound. Each of the at least three cranes is provided with at least two hooks for lifting, and a plurality of sets of wire hooking piece portions are installed at locations corresponding to the hooked portions on the lifting body,
The lifting jig is interposed between a plurality of wires hung on each hook so as to correspond to the plurality of sets of wire hanging pieces, and between the plurality of wires and the plurality of sets of wire hanging pieces. A plurality of pulley blocks provided to
7. The lifting jig according to claim 6, wherein a wire from one pulley block is hung around the pulley so as to perform uniform suspension for each hooked portion. The lifting jig further includes a bar-like body provided with a pulley of the hooked portion corresponding to one wire of the one crane and a pulley of the hooked portion corresponding to one wire of the other crane. And a bar-like body provided with a pulley of the engaged portion corresponding to the other wire of the one crane and a pulley of the engaged portion corresponding to the other wire of the other crane. The lifting jig according to claim 6 or 7.

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