JPH0220495Y2 - - Google Patents

Description

[Detailed explanation of the idea]

(Field of Industrial Application) This invention relates to a partially non-welded composite roller, and its purpose is to create a composite roller consisting of an outer layer and an inner layer, and the contact surface between the outer layer and the inner layer is not entirely welded. To provide a partially unwelded composite roller which is simple to manufacture and has high durability, in which only the boundary part between a shaft part and a shaft part is unwelded, and the other parts are welded. It is in. (Prior Art) Generally, a composite roller is formed by using different materials for the outer layer portion and the inner layer portion, respectively, and is used for various purposes. For example, composite rollers are often used as transport rollers, rolling rollers for non-metallic materials, rolling rollers for paper manufacturing, rolling rollers for rubber, rollers for rolling steel plates, and rollers for pipe manufacturing. The reason for this is that if a composite roller uses a solid or hollow tube core with high toughness and mechanical strength for the inner layer, and cast iron with a large heat capacity and strong wear resistance for the outer layer, This is because it is possible to recast the outer layer portion, which is easily subjected to thermal shock and suffers significant damage such as wear, in accordance with the damage to the outer layer portion. As such a composite roller or its manufacturing method, there is a method for manufacturing a cast iron roll having a cavity in the core disclosed in Japanese Patent Application Laid-open No. 51-98630, or a method for manufacturing a cast iron roll having a hollow core, or a method for manufacturing a cast iron roll disclosed in Japanese Patent Application Laid-Open No. 51-98630. 58−154449
``Method for manufacturing a cast iron roller having a steel core shaft'' disclosed in the above publication is well known. Furthermore, as a conventional technology for composite rollers made of cast iron, the bearing part of the roll shaft is made of the same material as the support at the end of the roll, and a composite roll of an annular body is formed integrally with the support. 50−
The technique disclosed in Japanese Utility Model Publication No. 37282 is known, and the technique disclosed in Japanese Utility Model Publication No. 4-2205 is known as a roller in which the entire outer layer is coated from both ends of the roll shaft. (Disadvantages of Prior Art) However, these disclosed techniques have various drawbacks. The roller disclosed in Japanese Utility Model Publication No. 4-2205 cannot be used in places where high heat is applied to the roller, such as in steel plants, because the outer layer is made of ebonite.
Since the roller disclosed in Japanese Patent No. 37282 has an outer layer made of a natural material, it is not only difficult to repair when worn, but also has the disadvantage that the roller itself is not easy to manufacture. These belong to the further prior art of cast iron composite rollers, as mentioned above. In addition, regarding these improved technologies for cast-in composite rollers, there is also the ``Manufacturing method for cast iron rolls having a hollow core'' disclosed in Japanese Patent Application Laid-open No. 51-98630, and the patent publication published by the inventors of this patent. Further research by the inventors revealed that the composite roller manufactured by the ``Method for manufacturing a cast iron roller with a steel core shaft'' disclosed in Publication No. 58-154449 had a serious drawback. Ta. This serious drawback is that carbon is transferred from the cast iron outer layer to the steel material that is the cast core shaft of such composite rollers through the welded part due to external heating (so-called carburization phenomenon), and as a result, the core The shaft becomes brittle,
Often, during use, the entire composite roller becomes unusable due to internal cracks and damage such as abrasion of the cast iron on the outer layer. The drawback is that it is not possible to reuse the composite roller by recasting it in response to damage. However, in order to avoid this carburization of the carbon steel core shaft, as in the past, the carbon steel core shaft is made into an irregular cross section to form protrusions, and the carbon steel core shaft and the outer layer of cast iron are fitted and integrated. In the case of composite rollers using a completely non-welded fitting method, the core shaft and outer cast iron separate during use, and only the outer layer cast iron rotates idle, making it impossible to achieve the purpose of the roller.Measures to solve the problem of carburization of the core shaft. I didn't like it as such. There was also a trial example in which a carbon steel core shaft with an irregular cross section was used, and only this irregular cross section was welded to each other at the contact surface with the outer cast iron layer. When using a carbon steel core shaft with this irregular cross section, it is necessary to set the welded part in a place where no concentrated stress is applied, and adjustment of the core shaft with an irregular cross section is difficult in manufacturing. In addition, even if the initial design is such that the welded part is located in a location where no concentrated stress is applied, it is difficult to control this during actual manufacturing, and the welded part is often located in a location where concentrated stress is applied. There were drawbacks associated with manufacturing difficulties. (Solution of the invention) This invention was completed in the process of elucidating the drawbacks of such various composite rollers.In other words, this invention consists of a carbon steel core shaft and an outer layer that covers the entire outer layer from both ends of this core shaft. The coated cast iron has a shaft part and a roller part that are integrated, and the inner roller part and the shaft part of the contact surface between the coated cast iron and the carbon steel core shaft. This relates to a partially non-welded composite roller in which only the boundary portion between the two is a non-welded portion in the form of a metal touch, and the other contact surfaces are welded. (Example) Hereinafter, an example of this invention will be described based on the drawings. In Figures 1A and B, 1 is a carbon steel core shaft,
This core shaft 1 may be a hollow tube or a solid tube,
Any material made of carbon steel with high toughness and strong mechanical strength can be suitably used. Reference numeral 2 denotes cast iron that covers the entire outer periphery of the carbon steel core shaft 1 from both ends 3 and 4. In this cast iron, the shaft portion A and the roller portion R are integrated. Reference numeral 5 denotes a contact surface between the carbon steel core shaft 1 and the cast iron 2 surrounding the outer periphery, and within this contact surface 5, at least the boundary portion between the roller portion R and the shaft portion A, that is, the contact ends 6, 7, 8 of the bearing portion, Parts such as 9, which are easily subjected to loads, are mutually unwelded in a metal touch shape, and the other contact surfaces are welded. In this invention, metal touch refers to a state in which the characteristics of the raw materials are mutually maintained as they are, that is, there is no material change, and the two are in close contact (tight). A state in which the material is in close contact with the material in a non-welded manner. The embodiment shown in FIG. 1 shows an embodiment in which the following specific method was adopted during production to form the non-welded portion. In this specific method, after degreasing the surface of the carbon steel core shaft 1, a specific surface treatment agent made of specific components is applied to
This method involves coating the non-welded area as many times as required to obtain a film thickness of 0.4 to 0.5 mm, then heating and drying this film, and then casting the outer layer to make the non-welded area into a metal touch. In this way, with this invention, among the contact surfaces 5 of the carbon steel core shaft 1 and the cast iron 2 enclosing its outer periphery, the load area where concentrated stress is likely to be applied, that is, the boundary between the roller part R and the shaft part A, is mutually The reason for choosing Metal Touch is that the core shaft of the composite roller often cracks internally during use, causing the mechanical strength of the entire composite roller to deteriorate, or that the core material of the composite roller often cracks during use. We clarified the reason why the entire composite roller becomes unusable due to cracks in the core material, even if you try to re-cast it and reuse it due to damage such as wear of the cast iron on the outer layer without realizing it. This is the result. That is, the initial purpose of the composite roller, which was to increase the mechanical strength of the entire roller, and to make the composite roller reusable by being recast in response to damage to the outer layer, was often not achieved. It consists of a carbon steel core shaft 1 and a cast iron 2 covering the outer periphery.
When the mutual contact surface 5 is fused, a so-called carburizing phenomenon occurs in which carbon components in the cast iron migrate into the carbon steel core shaft 1 due to heating during casting and during use, and this carburizing phenomenon occurs. The carbon steel core shaft 1 has significantly deteriorated mechanical strength such as a decrease in impact resistance and elongation, and as a result, the mechanical strength of the entire composite roll has decreased.
The inventors were the first to elucidate the cause of the adverse effects such as inhibiting the reuse of the composite roller, and completed this invention. (Effects of the invention) As detailed above, this invention consists of a carbon steel core shaft and coated cast iron of a desired shape that is rotatable and covers the entire outer layer from both ends of the core shaft. The roller part is integrated, and only the boundary between the inner roller part and the shaft part, which is the contact surface between the coated cast iron and the carbon steel core shaft, is a non-welded part in the shape of a metal touch. Since the contact surface of is related to a non-welded composite roller, the contact surface of the composite roller is in a non-welded state, that is, a metal touch, since the boundary between the roller part and the shaft part, where the load is mainly applied, is in a non-welded state. There is no carburization phenomenon from the outer layer on the core shaft, and therefore there are no drawbacks such as a drop in impact resistance or elongation of the core shaft, or damage during use, so it can be used for a long time as a composite roller. Furthermore, this non-welded part of the joint surface between the outer layer and the inner layer can be easily processed when forming the outer layer with cast walnut, and this part can be reliably made into a non-welded state, making it an extremely easy part to manufacture. It has the effect of being a non-welding type composite roller. The effects of this invention will be made clearer by describing Examples, Comparative Examples, and Test Examples below. Examples 1 to 3 and test examples Using a carbon steel solid rod with a diameter of 30 mm and a length of 500 mm as a core, the following surface treatment agent was applied three times to a thickness of
It was applied to a thickness of 0.4 to 0.5 mm. Incidentally, the surface treatment agent was applied to the entire circumference of the load portion of the core shaft. Example 1 Mixture of 50wt.% Pb ₃ O ₄ (powder) and 50wt.% LSS-35 (trade name, liquid properties, manufactured by Nissan Chemical Co., Ltd.) Example 2 50wt.% SiO ₂ (powder). Example 3 Mixture of 50wt.% LSS-35 (trade name: liquid, made by Nissan Chemical Co., Ltd.) 3 Pb ₃ O ₄ (powder) 40wt.% and LSS-35 (trade name, liquid: liquid) ．Manufactured by Nissan Chemical Co., Ltd.) 50wt.% and SiO (powder)
Comparative example of a mixture with 10wt.% No treatment After this surface treatment, it was dried in a heating drying oven at 200℃, and the outer layer was cast using the push-up method using two CO ₂ type upper-type feeders. . The casting temperature was 1200° to 1300°C, and after 24 hours, the mold was taken out when the surface temperature was 100°C. In addition, the maximum diameter of the composite roller for outer layer cast iron is 600mm.
It was cast to become. When these Examples 1 to 3 were divided after cooling, there was no carburized layer on the core shaft, and the boundary between the roller portion and the shaft portion was in the shape of a metal touch. In the comparative example, the hollow pipe and the cast layer were fused together, and a carburized layer was observed all around the circumference. Tests were conducted using the composite rolls of Examples 1 to 3 and Comparative Example. The results are shown in Table 1.

[Table] In addition, the test was performed by rotating 200 times and applying a load of 600 kg.
This is the result of repeating the load 140 times in one hour. As can be seen from the above results, it can be seen that the composite roller according to this invention has excellent effects.

[Brief explanation of the drawing]

FIG. 1A is an external view of a partially non-welded composite roller according to an embodiment of this invention, and FIG. 1B is a vertical sectional view of a partially non-welded composite roller according to an embodiment of this invention. . 3, 4... end, 5... contact surface, 6, 7, 8,
9... Load part, R... Roller part, A... Shaft part.

Claims (1)

[Scope of utility model registration request] It consists of a carbon steel core shaft and a rotatable coated cast iron having a desired shape that covers all the outer layers from both ends of the core shaft. Of the contact surfaces with the carbon steel core shaft, only the boundary portion between the roller portion and the shaft portion is a metal touch-like non-welded portion, and the other contact surfaces are welded. Molded composite roller.