JP2005060787A - Post-heating apparatus for welded part of steel sheets - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a post-heating apparatus for a welded part of steel sheets which performs the post-heating to the welded portion of the steel sheets after welding both steel sheets. <P>SOLUTION: This apparatus is provided with one or more burners 3 for heating the welding part 2, a copying mechanism 4 for holding the distance between the burner 3 and the welding part 2 according to the ruggedness of the steel sheets 1 so as to become constant, a height following means 8 for freely following the copying mechanism 4 in the height direction and a traversing means 10 for traversing the copying mechanism 4 in the direction in which the welding part 2 is extending. Further, it is suitable that the above copying mechanism 4 is the mechanism for copying the ruggedness of the steel sheets 1 by bringing the plurality of rollers 4a into contact with the steel sheets 1. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to a steel plate welded portion post-heating device that performs post-heating to remove a thermal effect during welding after welding steel plates.

  For example, when pickling steel plates in pickling equipment, the steel plates are welded and joined continuously to increase efficiency.

  In this case, as illustrated in FIG. 3, the front end of the steel plate 1 unwound from the uncoiler 31 and the tail end of the preceding steel plate are welded and joined with a flash butt welder 32 to make the steel plate continuous. Then, the continuous steel plate is sent to pickling equipment (not shown), which is a subsequent process of the bridle roll 33, and a predetermined treatment is performed.

  By the way, the portion welded in this way may become brittle and easily break due to the influence of heat, so that post-heating (also referred to as annealing) may be performed by the steel plate welded portion post-heating device 11.

  Conventionally, when post-heating is performed after welding steel plates, it is common to use an induction heating type post-heating device as disclosed in Patent Document 1.

  A conventional weld post-heating apparatus disclosed in Patent Document 1 will be described with reference to FIG.

  In the welding part post-heating device disclosed in Patent Document 1, first, the steel plate 1 is sandwiched and fixed between the upper clamps 14 and 15 and the clamp backing parts 16 and 17, and induction heating including the heating coil part 21 and the core part 22 is performed. The welding part 2 of the steel plate 1 is post-heated with the apparatus 20.

  Here, in Patent Document 1, deformation of the steel plate 1 caused by thermal stress is suppressed by a heat-resistant insulating spacer 23 arranged in the gap between the core portion 22 that performs induction heating and the steel plate 1 in the vicinity of the welded portion 2. It is characterized by this.

  The spacer 23 is a rod made of a heat-resistant insulating member such as ceramic that extends in the plate width direction of the steel plate 1, and is molded integrally with the core portion 22 while one side end thereof is in contact with the coil portion 21. While making the surface part of a side edge part oppose the steel plate 1, it is comprised so that the surface part and the backing surface of the backing parts 16 and 17 may be contained in the same plane. Further, a protective groove 24 is formed on the surface portion along the welded portion 2 to prevent contact with the welded portion 2. Furthermore, when the plate | board thickness of the steel plate 1 is thin, the some groove | channel 25 is formed in this surface part, and a contact area with the steel plate 1 is made small.

  In the apparatus of Patent Document 1, since the gap is always kept substantially constant as described above, temperature unevenness of the welded portion 2 can be prevented and annealing can be appropriately performed.

  In the case of the induction heating type, not only can the post-heating of the steel plate welded portion be performed in a short time, the temperature can be quickly raised to the target temperature, but temperature control can also be performed relatively easily.

  On the other hand, as a method of applying heat to the steel plate, a direct fire method using a burner is also possible.

Patent Document 2 discloses a device devised as an apparatus for annealing a steel plate welded portion, which includes first and second burners for heating the welded portion from both sides of the steel plate.
JP-A-5-69178 Japanese Utility Model Publication No. 62-175065

  Since the apparatus of Patent Document 1 clamps a steel plate and performs induction heating of a welded portion, there is a problem that the apparatus becomes complicated and the equipment cost increases.

  Moreover, since the apparatus of Patent Document 2 uses a burner, the equipment configuration can be simplified and the equipment can be made inexpensively. In order to prevent the deformation, in the first burner of Patent Document 2, the closest approach interval is regulated by inserting a steel plate pressing member between the steel plate and the steel plate. However, this steel plate pressing member also has a problem that it is thermally deformed by heating with a burner.

  By the way, even if induction heating or a burner is adopted as a post-heating method, there is no change in applying heat until a high temperature in the vicinity of the transformation point of the steel plate, and the steel plate easily undergoes thermal deformation. Therefore, the heat input is not stable, and the steel sheet is melted, or conversely, it is easy to cause breakage after passing the plate due to insufficient heat input.

  In order to solve this problem, no matter which method is adopted, as disclosed in Patent Document 1 and Patent Document 2, a clamping device that clamps a steel plate and suppresses thermal deformation is essential.

  However, when the shape change of the plate is large, a sufficient clamping force is often not obtained and the steel plate cannot be sufficiently restrained, so that the heat input necessary for post-heating cannot be performed.

  In particular, when a burner is used, heat is applied to the clamping device and the clamping device itself is thermally deformed, so that there is a problem that the life is shortened and the clamping accuracy is also deteriorated.

  The present invention solves the above problems, and provides a simple and inexpensive post-heating device that employs a direct heating method of a burner and that does not require a clamping device.

  The present inventor does not forcibly suppress the deformation of the steel plate, which is a problem when adopting the direct heating method of the burner as a post-heating device, but is stable by moving the burner according to the deformation. The inventor has conceived that heat can be input, and has reached the present invention.

  That is, the present invention is a steel plate welded portion post-heating device that performs post-heating of the welded portions of the steel plates after welding the steel plates, and includes at least one burner for heating the welded portions, and the burner. A scanning mechanism that keeps the distance from the welded portion constant according to the unevenness of the surface, a height follower that freely follows the scanning mechanism in the height direction, and a direction in which the welded portion extends. The above-mentioned problem has been solved by a steel plate welded portion post-heating device characterized by comprising a traversing means for traversing the copying mechanism.

  In the present invention, it is preferable that the copying mechanism is a mechanism that makes a plurality of rollers come into contact with a steel plate to copy the unevenness of the steel plate.

  According to the present invention, a steel plate welded portion can be stably post-heated using a burner, and a simple and inexpensive steel plate welded portion post-heating device can be provided.

  The best mode of the steel plate welded portion post-heating device of the present invention will be described with reference to FIG.

  Fig.1 (a) is the schematic diagram which looked at the steel plate welding part post-heating apparatus 11 of this invention from the front.

  The apparatus 11 according to the present invention includes a traversing apparatus 10 that can traverse freely in a direction in which a welded portion of the steel plate 1 (not shown here, see FIG. 1B) extends. The traversing method of the traversing device 10 is not particularly limited, and a method such as hanging the ceiling plate 9 of the device on a gate-shaped frame on the line and traversing by motor drive can be used.

  A pedestal 7 is attached to the ceiling plate 9 of the apparatus via a height following means 8, and one or more required number of burners 3 and the copying apparatus 4 are integrally connected to the pedestal 7.

  Here, each of the burners 3 is arranged so that the height of the end opening of the burner is constant toward the steel plate, and follows the welded portion of the steel plate 1 with a copying device 4 as a copying mechanism with a constant height. Has been. In addition, although the case where the number of the burners 3 is two is shown in FIG. 1, it is not limited to this, What is necessary is just to provide one or more burners. The number of burners may be set as appropriate according to the heating capacity of the burner and the amount of heat input required. When a plurality of burners are provided, the welded portion extends in the direction as shown in FIG. It is preferable to arrange them side by side.

  The copying device 4 is configured to contact the steel plate 1 with a plurality of rollers 4a, and freely follows the unevenness of the steel plate using the shaft 4c as a fulcrum. In the present invention, the copying apparatus 4 shown in the figure is adopted mainly for the purpose of inexpensively configuring the apparatus, but the copying apparatus 4 is not limited to this. For example, as shown in FIG. 1, in order to stably travel on a steel plate by a traversing device, it is preferable to contact the steel plate with a plurality of rollers, but with one roller, the direction in which the weld extends The copying apparatus may be arranged so as to be aligned with the burner in the orthogonal direction. Moreover, it can also be set as the apparatus which copies and controls so that height may become fixed, measuring the distance with a steel plate with a non-contact-type distance sensor.

  In the present invention, in order to enable the copying apparatus 4 to smoothly copy the steel plate 1, the height follower 8 is provided. Specifically, the height tracking means 8 can be configured to press and follow the copying apparatus 4 with a simple spring. Further, a damper such as air or hydraulic pressure may be employed. Furthermore, a control cylinder such as an air cylinder or a hydraulic cylinder can be employed to automatically follow the height according to the copying by the copying apparatus.

  In order to make the understanding of the present invention easier, a schematic view of the post-heating device of the present invention viewed from the side is shown in FIG.

  Needless to say, although the equipment cost increases, it is possible to use an induction heating coil to perform post-heating of the welded portion instead of the burner of the post-heating device of the present invention. At this time, in particular, in order to dispose the copying mechanism and the induction heating coil close to each other, it is preferable that the copying mechanism is made of an insulating ceramic that is not affected by the induced current. Further, the heating means can be an electric heater.

  Here, with respect to the steel plate subjected to the pickling treatment in the pickling line, verification was performed for the upper and lower scanning ranges when copying the unevenness with the steel plate welded portion post-heating device of the present invention.

  The verification is performed by setting the reference distance between the tip opening of the burner 3 and the upper surface of the steel plate (upper surface of the welded portion) to 23 mm and simply moving the burner 3 in the horizontal direction without using the copying apparatus. It was carried out by actually measuring the distance between the top surface of the steel plate and the steel plate. The result is schematically shown in FIG.

  As shown to Fig.2 (a), when the steel plate 1 is warped shape, the distance of the front-end | tip opening part of the burner 3 and a steel plate upper surface approaches 0-5 mm at the shortest. On the other hand, when the steel plate 1 has a downward warping shape, as shown in FIG. From the above knowledge, the amount of copying in the post-heating apparatus for steel plate welds of the present invention needs to be at least in the range of 40 mm.

  Based on the above knowledge, a post-heating apparatus for steel plate welding according to the present invention was manufactured.

  The height follower employs a spring mechanism, and the spring can be adjusted to freely follow more than 40mm vertically. The copying apparatus was configured to copy with four rollers, and two post-heating burners were arranged.

  As a result of post-heating after welding the steel plate to be pickled in the pickling line with a flash butt welder using the steel plate welded part post-heating device of the present invention shown above, the steel plate was broken during line conveyance. Did not occur. It has been verified by the present invention that sufficient post-heating can be performed with simple and inexpensive equipment.

It is a schematic diagram of the steel plate welded part post-heating device of the present invention. It is the schematic which put together the result which verified the curvature amount of the steel plate center part. It is a schematic diagram which shows an example of the welding joining line of the steel plate to which this invention is applied. It is a schematic diagram which shows an example of the conventional welding part post-heating apparatus.

Explanation of symbols

1, 1a, 1b Steel plate 2 Welded part 3 Burner 4 Copying device
4a roller
4b bracket
4c Axis 7 Base 8 Height follower 9 Ceiling plate
10 Traversing means
11 Steel plate post-heating device
14,15 Upper clamp
16, 17 Clamp backing
20 Induction heating device
21 Heating coil section
22 Core part
23 Spacer
24 Protective groove
25 groove
31 Uncoiler
32 flash butt welder
33 Bridle Roll

Claims (2)

A steel plate welded portion post-heating device that performs post-heating of the welded portions of the steel plates after welding the steel plates,
One or more burners for heating the weld;
A copying mechanism that holds the burner so that the distance from the welded portion is constant following the unevenness of the steel sheet;
Height following means for freely following the copying mechanism in the height direction;
Traversing means for traversing the copying mechanism in the direction in which the weld extends;
A post-heating apparatus for steel plate welds, comprising: The steel plate welded part post-heating device according to claim 1, wherein the copying mechanism is a mechanism that makes a plurality of rollers come into contact with a steel plate to copy the unevenness of the steel plate.

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