JPS5865590A - Production of clad steel - Google Patents

Abstract

PURPOSE:To form metallurgical bonds thoroughly and to produce a superior clad steel plate at a low cost, by feeding two sheets of dissimilar metallic plates superposedly, and heat-melting the joining line of the meeting parts of both plates, then feeding the plates superposedly with superposing rolls. CONSTITUTION:Two sheets of dissimilar metallic plates 1, 2, for example, a stainless steel plate and a carbon steel plate are brought closer to each other from different directions with guiding rolls 3, 4, and are sandwiched under pressure by superposing rolls 5, 5' and 6, 6'. In this state, a geometrical joining line 8 is formed in the parts 7 where both plates 1, 2 are met by the first rolls 5, 5'. The line 8 is swept back and forth with the laser beam 11 from the gun 10 of a laser beam device 9. If the superposed feed speeds of both plates 1, 2 and the sweeping speed of the beam 11 are controlled, the line 8 is heated uniformly over the entire line, whereby a molten part 12 is formed. Said part is sandwiched and tightly stuck under pressure immediately by the rolls 5, 5', whereby both metallic plates are bound metallurgically.

Description

DETAILED DESCRIPTION OF THE INVENTION The disclosed technology belongs to the field of manufacturing technology from dissimilar metal plates of clad steel for corrosion-resistant double pipe materials and the like.

Therefore, the present invention relates to a method for manufacturing clad steel in which dissimilar metal plates such as a carbon steel plate and a stainless steel plate are metallurgically bonded at their joint surfaces and polymerized. Dissimilar metal plates are brought close to each other from different directions in a Japanese writing pattern and polymerized using a polymerization roll, and then the joined part of both metal plates at the meeting point by the first polymerization roll is heated and melted using a radish or the like to achieve a metallurgical bond. This invention relates to a method for manufacturing clad steel made of aluminum.

As is well known, multi-layered metal plates are used as materials for storage containers for corrosion-resistant fluids or transportation piping, which have corrosion resistance in addition to pressure resistance and heat resistance.
It is desired that the metal plates be strongly bonded to each other to prevent cracking and the like.

In particular, when the lining material is a corrosion-resistant material and is designed to have a curved surface, compressive residual stress is required to prevent stress corrosion cracking.

Therefore, in order to meet this demand, it is optimal to use metal plates to make clad steel, but for example, the rolling method, which is the cladding method that has been used so far, requires a large rolling ratio.
Therefore, it requires a large amount of power and has the disadvantages of high cost, as well as poor accuracy. The problem was that it was extremely difficult to understand.

There is also an explosive bonding method in which cladding is achieved by instantaneously obtaining a large amount of energy, but it has the drawback that complete bonding cannot be guaranteed, and there are other problems such as the portion where the explosive bonding area is uniform is narrow.

There is also a build-up method, but it has disadvantages such as poor workability, easy surface misalignment, and fusion welding, which creates tensile residual stress due to welding heat and causes stress corrosion cracking.

The purpose of this invention is to solve the problems of the manufacturing method of clad steel sheets based on the above-mentioned conventional technology, and to solve the problem by heating and melting the linear parts of the joined parts in the process of bringing dissimilar metal sheets together and rolling polymerizing them in close proximity. It is an object of the present invention to provide an excellent method for producing clad steel, which allows cladding to be performed from the entire surface to a partial area in the cold using dwarf heat, and allows the thickness of the metal plate to be selected.

In accordance with the above-mentioned object, the structure of the present invention is such that dissimilar metal plates are sandwiched between opposing rolls from different directions and fed in a superimposed manner, and when they are closely joined by the first roll, Cold heating using a laser beam or the like is applied accurately over the whole line or in a partial line to melt the opposing metal plate surfaces, which are immediately joined and crimped with rolls and then transported forward to ensure a secure process. The gist is to obtain clad steel.

Next, embodiments of the present invention will be described below with reference to the drawings.

In the embodiment shown in Figures 1 and 2, 1 and 2 are stainless steel plates and carbon steel plates, respectively, which are dissimilar metal plates, and although they are deformed for the sake of illustration, the set thickness and width of each can be determined. It is unwound from a winding coil (not shown), approaches the guide rolls 3 and 4G from a different direction (in the illustrated embodiment, from a direction opened by 90 degrees), is wrapped around the first polymerization rolls 5 and 5', and is then rolled onto the rolls 5 and 5' for the next stage. The roll 6.6' is also Akita-fed so as to be forward-feeded.

Thus, both metal plates 1.2 by the first rolls 5, 5'
One geometric joining line 8 is formed as a joining part at the meeting part 7 of.

In this invention, the gun 10 of the Lede beam device t9 is provided facing the joining line 8, and can pump liquid back and forth between both ends of the joining line 8 by appropriate control. It is treated like this.

Therefore, by adjusting the superposition feeding speed of both metal plates 1 and 2 and the pumping speed of the Radhebeam 11 irradiated from the gun 10, the joining line 8 is heated throughout the entire line, forming a molten part 12. and immediately the first polymerization rollers 5, 5
', they are clamped together and metallurgically bonded.

In this case, since the laser beam 11 can be made extremely thin, it is possible to form the fused portion 12 even if one of the metal plates, for example, the stainless steel plate 1, is made considerably thinner.

Therefore, both metal plates 1 and 2 are metallurgically fused over the entire width and length, and are made into a clad steel 13 and manufactured as a product.

As for the clad steel 13 manufactured in this way, the edges 14, 14 are welded and sealed.
Even when stocked, rust and corrosion will not enter the interior from the edges, and for example, when manufacturing double pipes by cutting them to a specified size and roll forming them as shown in Figure 2. Since the metal plates 1 and 2 are clad bonded, no displacement occurs, and compressive stress remains on the stainless steel plate 1 side, which prevents stress corrosion cracking during operation and provides a complete metallurgical bond. Therefore, the occurrence of cracking, insolation, etc. can be avoided.

In this case, since the fusion bond between the two metal plates 1 and 2 is cold low heat input welding, there is no tensile residual stress, which together helps prevent stress corrosion cracking.

It is also possible to form four pressure vessels by predetermined sizing.

In the above-mentioned embodiment, heating and melting is performed over the entire joining line 8 of the meeting portion 7 formed by the two dissimilar metal plates 1 and 2, so that the entire surface is clad. As shown, heating melting parts 12', 12'.

12' may be applied only to both end edges and the center part. Note that the embodiments of the present invention are of course not limited to the above-mentioned embodiments; for example, in place of the Lede beam, '
Various methods can be adopted, such as welding using a beam beam or gas burner scanning.

As described above, according to the present invention, in the Clara P steel manufacturing method in which two metal plates are welded and polymerized, the two metal plates of different types are brought close to each other from different directions, and the bond formed by the first polymerization roll is By applying cold heating and melting to the joining line part at the part and immediately polymerizing and sandwiching it,
Basically, the metallurgical bond formed between the two metal plates is completely formed without any change in the surface of the two metal plates, which has an excellent effect, and can be performed regardless of the wall thickness of the two metal plates. This has the effect of making expensive plates such as stainless steel plates thinner and reducing costs.

In addition, since cold melting is performed, no tensile residual stress is formed in the thick wall parts other than the fused parts, which has the excellent effect of preventing stress corrosion cracking from occurring in double pipes and containers made of product clad steel sheets. is played.

Furthermore, since melting is carried out at the joining part, that is, in an open state, it is possible to cause melting to occur both over the entire joint line as well as in parts, making it possible to fully metallurgically join the entire surface of clad steel or to partially join. Another advantage is that the metallurgical bond is perfect, so when a product is made of clad steel and bent into a double pipe, there will be no misalignment between one metal plate and the other. Therefore, compressive residual stress is formed, which, together with the absence of tensile residual stress, has the effect of preventing stress corrosion cracking from occurring.

[Brief explanation of drawings]

The drawings show an embodiment of the invention, and FIG.
FIG. 2 is a schematic explanatory diagram of an embodiment, FIG. 2 is an explanatory diagram of manufacturing a double pipe made of clad steel, and FIG. 6 is a partial schematic explanatory diagram of another embodiment.

Claims (1)

[Claims] In a method for manufacturing clad steel in which two dissimilar metal plates are polymerized through metallurgical bonding, when the two dissimilar metal plates are brought close to each other and fed for polymerization by a polymerization roll, the first straight meeting point of the polymerization roll is A method for manufacturing clad steel, characterized in that the joined portion of both metal plates is heated and melted to form a metallurgical bond and then polymerized and fed.