KR20020051257A - Method for extending the length of the crane girder - Google Patents

Abstract

PURPOSE: A method for extending a crane girder is provided to reduce constructing time by decreasing or extending a crane span and to reduce a repair cost by supplying a crane. CONSTITUTION: A device for extending a crane girder comprises a trolley having a winder; a hook beam installed on the winder of the trolley; a driver's room girder mounted on an inner portion of driver's seat; a curtain girder having a curtain cable; a connecting beam engaging the girders; a traveling device; upper and lower plates(21,22) fixing cutting portion member of the crane girder; side plate controlling plates(23,24); side face extending plates(26,27,28) inserted to an extended portion; an extending plate(31) reinforcing a middle portion; and an extension plate(32) reinforcing an inner portion. The cutting portion of the girder is applied to minimum bending moment. Thereby, the device for extending the crane girder reduces constructing time by decreasing or extending a crane span. Moreover, the device for extending the crane girder reduces a repair cost by supplying the crane.

Description

Method for extending the length of the crane girder}

The present invention relates to a crane girder extension method for easily performing the relocation of the ceiling crane, and more specifically to compensate for the difference in the strength or deflection of the girder due to the difference in the crane runway of the factory to install the existing overhead crane. It relates to a method for extending the crane girder.

In general, a ceiling crane is used to carry a heavy object, and the overhead crane travels along a girder.

When relocating the existing crane to another factory, if there is a difference in the girder length, especially when the length of the crane girder to be relocated is relatively short compared to the installation length of the factory to be relocated, Extend the length of the crane girder.

Since the method of extending the length of the crane girder involves the risk of safety accident due to thermal deformation or unstable coupling of the girder during the cutting extension work, a new crane girder is usually manufactured and used.

Therefore, since the existing crane girder must be disposed of, the resources are not effectively utilized, and the operation of the plant to be relocated as much as the time required to manufacture a new crane girder is stopped, which is inefficient for product production.

The present invention has been made to solve the conventional problems as described above, if there is a difference between the span of the crane and the runway girder, instead of a new production by replacing the shortened or extended by the difference in the air in the production plant The purpose is to provide a crane girder extension method that can use the crane in a short time and minimize the cost of retrofitting.

1 is a plan view showing a ceiling crane device.

Figure 2 is a side view of the overhead crane device.

Figure 3 is an explanatory view showing a working method for cutting and extending the girder according to the present invention, (a) is a side view, (b) is a sectional view.

Figure 4 is a view showing a cut portion of the crane girder according to the present invention.

5 is a view showing the amount of camber along the longitudinal direction of the crane girder.

Figure 6 is a view showing an extended state of the cutting section of the crane girder, (a) is the outer side view, (b) is the inner side view.

<Description of Symbols for Major Parts of Drawings>

12, 13: girder

21, 22, 23, 24: template for adjustment

26, 27, 28, 29, 30: extension

31, 32: stiffener extension plate

In order to achieve the above object, according to the present invention, a method of extending the crane girder of a pair of frame-structured structure is installed parallel to each other to support the movement of the overhead crane carrying a heavy object is that the bending stress of the crane girder is Cutting diagonal points of parallel girders so as to minimize the amount of remodeling; and setting a girder camber amount adjustment reference point after cutting by drawing a horizontal line with a transit sheet at each cutting part of the girder and marking an intermediate reinforcement insertion section; , Welding both ends of the adjusting bolts and nuts of the upper and lower plate adjusting template to the upper and lower plates, and then tightening the bolts to close contact with each other, and welding the nuts of the adjusting bolt in the middle to the upper and lower plates, and then tightening the bolts to closely contact them. .

Hereinafter, with reference to the accompanying drawings will be described a preferred embodiment of the present invention.

The ceiling crane has a trolley 11 with a hoist with a hook beam 1, a cab girder 12 with an electric compartment inside the cab 2, and a curtain with a curtain cable for power supply to the trolley 11 The side girders 13, the connecting beams 14 which connect the girders 12 and 13, and the traveling device 15, and the girders 12 and 13 have a frame structure.

According to the present invention, the work tool applied to extend the crane girder (12, 13) and the upper and lower plate adjustment template (21, 22) for aligning and fixing the members of the cut portion, the side plate adjustment template (23, 24) and , Side extension plates 26, 27, and 28 inserted into the extended portion, upper and lower extension plates 29 and 30, intermediate reinforcement extension plates 31, inner reinforcement extension plates 32, and a girder body It consists of an adjustment bolt mounted on the adjustment template welded to the fitting to fit the connection of the cutting member.

In addition, the extension method of the crane girder is divided into suspension work, cutting work and connection work.

First, the suspension operation will be described.

The cut extension portions of the girders 12 and 13 are exerted with a minimum bending moment on the same cross section. That is, in the girder (12, 13), the cut extension portion does not require the movement of the electric chamber panel (cable replacement and relocation), and the interference such as the point that is easily shifted to one side, the walkway, the handrail, etc. Consider a few places. Therefore, the cut extension portion in the cab girders 12 is the first point 12a after the last panel arrangement against the cab, and the cut extension portion in the curtain side girder 13 is the first point 12a. It is assumed that the second point 13a corresponding to the diagonal position of.

With the girders 12 and 13 seated on the stand before the modification, the camber suspend d is measured using a transit for each intermediate reinforcement section to compare with the design value and to the upper part of the side girders to extend. Draw a horizontal line on both sides of the girder with a transit at the point and mark the reference point (e).

The side extension plates 26, 27, and 28 subjected to the bending stress form a cutting line f, not a straight line, in order to reduce the strain restriction due to the concentration of the weld line, and to prevent stress concentration at the cutting edge edge. In addition to the length is further cut to have a curvature (c).

The upper plate 29 subjected to the compressive stress and the lower plate 30 subjected to the tensile stress are in a straight line so that the cutting line does not overlap the side extension plates 26, 27, 28.

Hereinafter, the cutting operation will be described.

The torch is preheated (50 to 70 ° C) and gas cut with a torch. After moving the cutting side girders, the cutting edges are removed and bevelling for V welding with a grinder.

Fine-adjust the cutting side girder to adjust the horizontality of the fixed side girder marking point (e) with a transit while adjusting the spacing of the intermediate reinforcement extension plate 11 and the straightness of the side extension plates 26, 27, 28. While reconfirming, the lower part of both girders on the cutting side is adjusted by the oil jack of the stand, and the level is adjusted by the transit.

Hereinafter, the welding operation will be described.

Weld the nuts of the adjustment bolts at both ends of the upper and lower plate adjustment plates 21 and 22 to the upper and lower plates, and then tighten the bolts to tightly contact each other. The plate is inserted, and the close contact portions of the upper and lower plate adjustment templates 21 and 22 and the side plate adjustment templates 23 and 24 are welded to the upper and lower plates.

In order to eliminate the bending part of an extension part, the welding part of the side extension plates 26, 27 and 28 and the upper and lower extension plates 29 and 30 is gouged.

The reinforcement plate is processed in consideration of the weld shrinkage and camber amount in consideration of the bending of the cutting line, the margin of beveling and the spacing of the welding root during the actual cutting work.

In order to disperse the stress in the welded portion of the intermediate reinforcement extension plate 31, the welded portions of the side extension plates 26, 27 and 28 and the upper and lower extension plates 29 and 30 are further welded to the intermediate reinforcement side.

The girder 12 and 13 and the connecting beam 14 are assembled in the template and reinforcement plate welding state, thereby correcting the assembly state of the flange. The flange plate is fastened with a reamer bolt, and the toe-in is generated in the connecting beam as the length of the girders 12 and 13 extends, but it returns from the load state and becomes vertical.

However, if the reamer holes do not match due to the difference in welding deformation between both girders when assembling the girders 12, bolt the connecting beam flange with camber suspend to support the girders' span and the right angle of the girder span. After adjusting the degree, the flange of the girder extension and the connecting beam 14 are welded together.

One side fabrication of both beams is re-adjusted to the girders to confirm attachment, and the existing flanges of the beam are cut and welded.

In the case of advanced skill, it is possible to calibrate the connection of the girder with a torch without making a correction of the flange.

The girder connection welding operation is performed after preheating to 50 to 70 ° C. in the state where the girder 12 and 13 and the connecting beam 14 are assembled, and then the lower plate 30, the side extension plates 26, 27 and 28, and the upper plate ( In the order of 29), three or more layers are welded in a V-type without a back plate, and the back surface is welded and grindered after gauging the back bead part.

The welding rod is used as an electric welder gouge by using a low hydrogen system in a drying furnace at 300 to 350 ° C. for 1 to 2 hours, and inspecting the weld defects by inspecting all welded joints.

The coating film near the welding line is removed, the water and oil at the welding part are completely removed, the coating is performed after welding, and the welding layer is thick, so that multilayer welding is performed without wearing. At this time, the bead thickness per layer is within 3mm, the temperature between each layer is within 150 ℃.

After connecting welding, the intermediate reinforcing material 31 and the inner reinforcing material 32 are welded, and if necessary, reinforcing material is added between the intermediate reinforcing members of the connecting welding section, and the intermediate reinforcing material 31 is carried into the girder before connecting welding, and the upper and lower plates Weld edge of chamfering process.

After the corrective work, the camber amount is measured by the transit for each section of intermediate reinforcement with the girders 12 and 13 seated on the stand and compared with the design value.

The left and right high and low deviations of the transverse rails of the trolley 11, in which the cutting extension positions of the girders 12 and 13 are different, are corrected with a taper liner at the bottom of the rail, and the taper liner is not separated during operation. Weld on).

By shortening or extending the crane span, it is possible to provide a crane in a timely manner by shortening the air in the production plant and to minimize the modification cost.

The foregoing is merely illustrative of the preferred embodiments of the present invention and those skilled in the art to which the present invention pertains may make modifications and changes to the present invention without departing from the spirit and gist of the invention as set forth in the appended claims. It should be recognized.

Claims (3)

In the method of extending the crane girders of a pair of framed structure is installed in parallel with each other to support the movement of the overhead crane carrying a heavy object, Cutting diagonal points of the parallel girders so that the bending stress of the crane girders is small and the amount of modifications is minimized; Setting a girder camber amount adjustment reference point after cutting by cutting a horizontal line with a transit sheet on each cutting part of the girder and marking an intermediate reinforcement insertion section; A crane comprising the steps of welding the bolts and nuts for adjusting the upper and lower plates of the upper and lower plates to the upper and lower plates and then tightening the bolts to close contact with each other. How to extend the girder. The method of claim 1, A method for extending a crane girder, characterized in that the side extension plate subjected to bending stress is cut along a cutting line of a bent shape rather than a straight line in order to reduce the amount of deformation caused by the welding line concentration. The method of claim 1, Crane girder extension method characterized in that to give a curvature to the edge by further cutting to the extension length to prevent stress concentration of the cutting edge edge.