JPH0144440B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for aligning metal structures such as ship hulls and bridges.

Conventionally, when building or modifying a ship, the general practice was to transport the hull blocks made on land to the dock or dock, and then join the blocks A together as shown in Figure 1. However, such a combination of blocks is performed using the following procedure.

(1) Load block A onto the platform.

(2) Make eye contact with Block A comrades. (See Figures 2 and 3) (a) Weld the alignment foot a to the part where the blocks A are to be joined together.

(b) Insert a metal arrow b between the eye alignment presser foot a and the eye alignment part, and align blocks A together.

(c) Perform tack welding c inside the groove.

(3) Perform final welding of the block joint.

Ships are built by repeating the above-mentioned steps, but this type of alignment work has the following problems.

(1) Weld the eye matching presser foot a to the eye matching part,
Since the alignment presser foot a is removed after tack welding c, scratches remain on the base material, which must be repaired by overlay welding or grinding work.

(2) Since tack welding c is performed inside the groove, when performing main welding, after one side welding is completed, it is necessary to remove the defective welding part of the tack welded area by gouging etc. on the back side. After this, the main welding is performed again from the back side, which increases the number of man-hours.

(3) Since welding is performed after forcibly aligning using presser foot a, the amount of distortion increases.

The present invention aims to solve the above-mentioned problems associated with the assembly of metal structures, and it is possible to deform plates locally by appropriately heating and cooling aggregate welded plates. The purpose is to provide a construction method that allows for alignment.

Therefore, in the construction method of the present invention, the blocks of a structure consisting of a metal plate and a plurality of aggregates welded to the same plate and intersecting each other are aligned before joining together at the edges of the plates. In this process, the plate material is heated in a direction substantially along the aggregate in the area where the blocks are to be connected, and then cooled to correct misalignment in the area, and to prevent the aggregates from crossing each other. A feature is that the direction of heating and cooling of the plate material is set to draw a circular arc in the vicinity of the portion.

Hereinafter, a method for aligning steel hull blocks as an embodiment of the present invention will be explained with reference to the drawings. FIG. 4 is a perspective view of the hull block, FIG. 5 is a plan view of the hull block, and FIG. FIG. 4 is a view taken along the arrow in FIG. 4;

As shown in FIGS. 4 to 6, a steel aggregate 2 is fixed to a steel upper deck plate 1 by welding 3 to form a hull block A as a steel structure.

Then, prior to joining the hull blocks A together, alignment is performed, and at that time, the following operations are performed at the portions where the hull blocks A are to be connected.

That is, the operation of heating the plate material 1 in a direction along its aggregate 2 and then cooling it is performed in the following procedure.

Assuming that P in Fig. 6 is the thickness center position of aggregate 2 when aggregate 2 is welded to plate 1, and Q is the weld line position when aggregate 2 is welded to plate 1, then The plate material 1 is heated and cooled linearly along the P position from position 4 to position 5 as shown in FIG.

Further, from the convex side of the distorted plate 1, it is heated and cooled from position 6 to position 7, as shown by the arrow, approximately along the Q position. In other words, a portion that is heated linearly along the aggregate 2 and a portion that is heated in an arc near the intersection of the aggregate 2 are:
It is heated continuously and then cooled.

In this way, the heating and cooling of the plate material 1 is performed in a direction substantially along the aggregate 2, and in particular near the intersection of the aggregates 2, the heating and cooling are performed smoothly in a circular arc, so that the hull block A The misalignment at the edge of the plate material 1, which serves as the joint portion, can be appropriately corrected.

If the misalignment of the parts to be connected cannot be sufficiently corrected even after these heating and cooling treatments, heat the parts further along the arrows 8 to 9 in Fig. 5, and then cool them. .

After the above-mentioned operation corrects the misalignment of the parts to be connected and completes the alignment work, the hull blocks A are joined together by one-sided semi-automatic welding or automatic welding.

In this way, according to the alignment method of the present invention, the following effects and advantages can be obtained.

(1) Since there is no tack welding within the groove, single-sided welding is possible, significantly reducing welding man-hours.

(2) Since there is no need to attach an alignment horse (see reference numeral a in Figures 2 and 3), there is no need to install an alignment horse, overlay welding, grinder work, etc. when removing it, reducing man-hours. can be measured.

(3) According to the construction method of the present invention, alignment work is particularly easier when the plate thickness is thick or when the plate bones of the aggregate are thick, compared to conventional construction methods.

(4) There is less strain relief work after the main welding, and the entire work is simplified.

(5) The plate material in the block is heated in a direction almost along the aggregate and then cooled. Especially near the parts where the aggregate intersects with each other, the direction of heating and cooling of the plate material is in a circular arc. Since the setting is made so that the above-mentioned blocks are connected, misalignment at the edge of the plate material serving as the connecting portion of the blocks can be appropriately corrected.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a ship's hull as a metal structure, FIGS. 2 and 3 are perspective views showing conventional alignment means, and FIGS. 4 to 6 are perspective views showing a conventional alignment means. 4 is a perspective view thereof, FIG. 5 is a plan view thereof, and FIG. 6 is a view taken in the direction of the arrow in FIG. 4. 1... Plate material as an upper deck, 2... Aggregate, 3...
...Welding location, 4 to 9... Heating position, A... Hull block, P... Aggregate plate thickness center position, Q... Welding line position.

Claims (1)

[Claims] 1 When aligning the blocks of a structure consisting of a metal plate and a plurality of aggregates welded to the same plate and intersecting each other at the edges of the plates, the blocks are connected. By heating the plate material in a direction substantially along the aggregate and then cooling it, the misalignment of the plate material is corrected. A method for aligning metal structures, characterized in that the heating and cooling directions are set to draw an arc.