JPS6218475B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a crane girder constructed by assembling pipes in a truss shape.

Conventionally, a truss structure composed of members having a circular cross section is generally constructed by directly welding a main pipe and a branch pipe. For example, a main pipe 1 as shown in FIG.
In a simple plane truss structure consisting of branch pipes 2a and 2b, the main pipe 1, branch pipe 2a, and branch pipe 2b in section A in the figure are connected by directly welding the branch pipes 2a and 2b to the main pipe 1, as shown in Fig. 2. 3 and are combined. In such a welded truss structure, when a load P ₀ in the direction of the arrow is applied to the tip of the non-fixed side in Fig. 1, a load P in the direction of the arrow is applied to the branch pipe 2a in Fig. 2, and the joint of the branch pipe 2a The main pipe 1 is locally deformed as shown in FIG. 3, and a large local stress is generated.

The fourth method for reducing such local stress is
As shown in Fig. 5, a reinforcing plate 4 is attached to the joint of the main pipe 1 and branch pipes 2a and 2b by welding 6, and then the branch pipe 2a and branch pipe 2b are attached to the reinforcing plate 4 by welding 6a and 6b. has been adopted. In this way, by increasing the thickness of the main pipe at the joint by welding the reinforcing plate, local stress can be alleviated. However, in a truss structure composed of a member having a circular cross section in which a branch pipe is directly welded to a main pipe, there are additional problems as described below. In other words, (1) Welding a branch pipe to the main pipe causes welding deformation in the main pipe. For example, by welding the branch pipes 2a and 2b to the main pipe 1 as shown in Figure 6, the main pipe 1 will be deformed as shown by the dotted line in the figure, so the accuracy of straightness and horizontality will be affected. Production management is difficult for items with high requirements.

(2) In general, a truss structure consisting of members with a circular cross section as a structure requires several branch pipes to be connected to the main pipe as shown in Figure 6, making it difficult to manufacture. It takes time and the quality of welding is lower than that of welding plate materials.

(3) In addition, both ends of the branch pipe must be processed to ensure close contact with the main pipe, while taking into account dimensional tolerances to prevent large positional deviations when attached to the main pipe.

(4) Strength reliability is also significantly reduced due to welding deformation and deterioration of welding quality.

It has many problems such as

An object of the present invention is to provide a girder constructed by assembling a main pipe and a branch pipe having a circular cross section in a truss shape through joint pieces, which is suitable for moving a trolley, has less deformation, and is easy to assemble. The goal is to have a structure that is good, lightweight, and has high strength.

In the present invention, the cross section of the girder is triangular, one side of which is located in the horizontal direction, and the apex is located at the top of the center of this one side, and main pipes are arranged in each part of the triangle. A rail receiver with a T-shaped cross section is installed so that the three main pipes, three joint pieces, and three branch pipes are located in the cross section of the girder at the joint piece. A seat is provided along the main pipe at a position diagonally above and outside the center of each lower main pipe.

Hereinafter, the present invention will be explained in detail using the figures.

First, the joint piece will be explained.

Figures 7 to 10 show an example of a joint piece, and Figure 7 is a cross-sectional view of a joint piece manufactured by welding that has two branches.
5a is a right-angle branch pipe, 5b is an oblique branch pipe, 5 is a joint piece body, 7a is a welding part that connects the joint piece body 5 and the right-angle branch pipe 5a, and 7b is a joint piece body 5 and the diagonal branch pipe 5b. The joint piece connects the right-angled branch pipe 5a and the diagonal branch pipe 5b to the joint piece main body 5.
are connected to each other by welding 7a and 7b.

Moreover, FIGS. 8 to 10 are explanatory diagrams of a method for connecting the main pipe and branch pipe using the joint piece.

In Figures 8 to 10, 1 is the main pipe, 2a, 2b
50 is a joint piece in which the branch pipes 5a and 5b are joined to the joint piece main body shown in FIG. 9b
is a welded portion between the branch pipes 2a, 2b and the branch pipes 5a, 5b. The connection between the main pipe 1 and branch pipes 2a and 2b is as follows:
According to the following steps. That is, (i) In FIG. 8, first, the main pipe 1 is passed through the joint piece 50, and the joint piece 50
is placed at a predetermined position on the main pipe 1.

(ii) Next, branch pipes 2a, 2b and joint piece 50
For connection, the branch pipe 2a is inserted into the branch pipe 5a of the joint piece 50 in the direction of the arrow in FIG. 9, as shown in FIGS. 9 and 10 as an example of the connection with the branch pipe 2a. In this case, the length of the branch pipe 2a is pre-processed so that there is a slight gap between the tip of the branch pipe 5a of the joint piece 50 at the bottom of the figure and the lower part of the branch pipe 2a.

(iii) Next, as shown in FIG. 10, move the branch pipe 2a in the direction of the arrow and insert the branch pipe 2a into the branch pipe 5a of the joint piece 50.

(iv) After the branch pipes 2a, 2b are inserted into the branch pipes 5a, 5b of the joint piece 50 as described above, the branch pipes 2a, 2b and the main pipe 1 are welded together via the joint piece 50. 9a, 9
They are bonded to each other at b.

The effects of this embodiment in which the branch pipes 2a and 2b and the main pipe 1 are connected using the joint pieces 5 and 50 are as follows.

(1) The thickness of the main pipe at the branch pipe joint is increased by the joint piece, and local stress is alleviated.

(2) Since the branch pipe is connected to the joint piece,
Welding deformation of the main pipe is less likely to occur.

(3) Branch pipe dimensions and management are easy.

(4) By manufacturing the joint piece separately, the welding quality of the branch pipe attachment area is good.

(5) It is easy to weld the joint piece to the main pipe and branch pipes, making it easy to assemble.

(6) Since joint pieces are used to connect the main pipe and branch pipes, the rigidity is higher than that of conventional truss structures.

(7) The allowable stress increases due to stable welding quality, prevention of welding deformation, and the reinforcing effect of the joint piece at the joint between the main pipe and branch pipe, and furthermore, the strength reliability increases significantly.

Figures 11 and 12 show joint pieces that are other embodiments of the present invention. Figure 11 shows a joint piece 10 having a branch pipe formed by plastic working, and Figure 12 shows a joint piece 10 having a branch pipe formed by plastic working. This figure shows a joint piece 11 having a branch pipe made of cast steel.

Such joint pieces 10 and 11 are replaced with joint piece 5 shown in FIG.
By using it as a joint piece for the main pipe 1 and branch pipe 2 shown in Figures 1 to 10, the following effects can be obtained. The plastic processed product of joint piece 10 is
Compared to the joint piece 5 described above, there is no welding at the branch pipe attachment part, so there is no notch effect at the welded part.Moreover, the material strength is increased by plastic working, the quality is stable, and the manufacturing cost is lower than that of welded products. cheap.

Next, compared to the joint pieces 5 and 10, the cast steel joint piece 11 has the advantage that the shape and wall thickness of the branch pipe attachment part can be freely selected, and stress concentration and local stress can be alleviated to a large extent. It is.

Figures 13 to 15 also show joint pieces that are other embodiments of the present invention. Figure 13 shows a joint piece, and Figures 14 and 15 show a truss structure using the joint piece. They are a plan view and a sectional view. What is different from the embodiment shown in FIGS. 7 to 10 above is that the joint piece 12 that connects the main pipe 1 and branch pipes 2a and 2b is a joint piece main body that has branch pipes 12a and 12b that are connected to the main pipe 1. 1
As shown in the figure, a joint piece 12 is attached by welding 14 to the main pipe 1 reinforced with a reinforcing member 13 to connect it to the branch pipes 2a and 2b.

According to this embodiment, there is an effect that the main pipe and the branch pipe can be connected using the joint piece even in a portion where the main pipe cannot pass through the joint piece.

Next, one embodiment of the girder of the present invention will be described in detail.

Figure 16 shows the most common container crane installed in ports. In Figure 16, 3
1 and 32 are girders, 33 are trolleys, 34 are hanging tools, 35 are containers, 36 and 37 are portals, 3
8 is a tension bar.

As is clear from the figure, in the container crane, a trolley 33 with a container 35 hoisted by a hoist 34 moves across girders 31 and 32 supported by portals 36 and 37 and a tension bar 38. As the girders 31 and 32, FIGS. 17 to 19 show an example of a container crane girder having a steel pipe truss structure having a circular cross section to which the present invention is applied.

In the figure, 1a is an upper main pipe, 1b is a lower main pipe, 2a to 2d are branch pipes for connecting the main pipes 1a and 1b, and the branch pipes 2a to 2d are all connected to the main pipes 1a and 1b by a joint piece 50. . Moreover, the rail 20 for trolley traverse is installed on a T-shaped rail receiver 27 attached by welding to the lower main pipe 1b. As is clear from the figure, the end of the vertical piece of the rail receiver 27 is connected to the lower main pipe 1.
6, and one end of the horizontal piece is welded and fixed at a tangential position on the upper surface of the lower main pipe 1b.

In such a crane girder, the side branch pipes mainly share the load in the vertical direction, and the lower face branch pipes mainly share the bending load.

By configuring the girder in this way, the following effects can be obtained.

(1) Good workability and can greatly reduce manufacturing man-hours.

(2) Since the main pipe passes through the joint piece continuously, the levelness and straightness of the girder can be controlled reliably and accurately. This is because the rail receiving seat is installed on this main pipe, so that the levelness and straightness of the rail can be accurately and easily achieved.

(3) Local stress can be greatly alleviated, greatly increasing the strength and reliability of cranes that handle large loads.

(4) The joint piece increases the rigidity of the joint between the main pipe and the branch pipe, reducing deformation of the girder when a load is applied.

(5) Since the girder has a truss structure with a triangular cross section on the plane where the main pipes intersect perpendicularly, it has extremely high strength due to its triangular nature, and is also lightweight compared to other truss structures with a polygonal cross section. .

(6) The load from the trolley passing through the rail is transmitted from each piece of the rail receiving seat to the main pipe in the tangential direction of the main pipe, so the load acting on out-of-plane bending of the main pipe is small and no stress is applied to the main pipe, and the thickness and thickness of the main pipe are reduced. Can withstand large loads without increasing diameter.

In addition, the load from the trolley is applied to the main pipe in a way that twists it, but since the main pipe is a pipe, it has the property of exhibiting strong resistance to twisting force. He has an excellent ability to convey information. Therefore, the main pipe which receives the load from the trolley as a torsional force disperses the torsional force over a wide range along the main pipe. Therefore, the torsional force, that is, the load from the trolley, can be supported even by branch pipes that are far from the point of load application, and the load per branch pipe is reduced, making it possible to provide a girder that is even lighter and has higher strength and reliability. It is.

As described above, according to the present invention, the rail receiving device is particularly T-shaped, and one end of the vertical piece and one end of the horizontal piece are arranged in the tangential direction of the side surface and the top surface of the main pipe, respectively.
Since the trolley is located at or near the rail receiving seat, the load from the trolley is easily transmitted to the main pipe via the rail receiving seat. Therefore, it is possible to provide a girder that can withstand large loads.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a general truss structure, Figs. 2 and 4 are side views of the joint between the main pipe and branch pipe, Figs. 3 and 5 are cross-sectional views of Figs. 2 and 4, respectively; FIG. 6 is an explanatory diagram of welding deformation in a truss structure, and FIGS. 7, 11, and 12 are sectional views showing joint pieces according to the present invention, respectively.
FIGS. 8 to 10 are explanatory diagrams of a method for connecting main pipes and branch pipes constituting a truss structure according to an embodiment of the present invention;
Figures 13 to 15 are explanatory diagrams of modified examples of the present invention, in which Figure 13 is a joint piece diagram, Figure 14 is a truss structure diagram using the joint piece, and Figure 15 is a cross section of the truss structure. Figure 16 is an overall view of the container crane, Figure 17 is a plan view of an embodiment of the present invention of a steel pipe truss girder used in a container crane, Figure 18 is a side view of the steel pipe truss girder shown in Figure 17, and Figure 19. 17 is a sectional view of the steel pipe truss girder of FIG. 17. 1... Main pipe, 2a... Branch pipe, 2b... Branch pipe, 5... Joint piece, 5a... Right angle branch pipe, 5b... Oblique branch pipe, 7a, 7b... Welded part, 8... Welded part, 9a,
9b...Welding part, 10...Joint piece, 11...
Joint piece, 50...Joint piece.

Claims (1)

[Claims] 1 The shape of the girder in a cross section perpendicular to the longitudinal direction of the girder is triangular, one side of the triangle is located in the horizontal direction, and the apex of the triangle is located at the upper center of the side. A main pipe is located at each corner of the triangle, and the main pipe has a circular cross section and is continuous along the girder, and joint pieces are fixed to each main pipe at predetermined intervals. A branch pipe with a circular cross section is fixed between the joint pieces, and three main pipes, three joint pieces, and three branch pipes are located in the cross section of the girder in the joint piece part, A girder for cranes in which rail receivers that are continuous along the main pipe are fixed at positions outside the center of each lower main pipe, and the rails are installed on the rail receivers.