JPH022928B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a stainless steel strip with excellent stain resistance. No. 3, No. 3 polishing finish for stainless steel strips.
There are various conventional types such as No. 4 and No. 7, but those with a fine and uniform polished surface are considered good in terms of appearance. However, when such polished stainless steel strips are used for parts that require cleanliness, such as sink top materials, they can be easily removed even if various foods are attached to them, in addition to the appearance, and they can also be cleaned after removal. It is necessary that the marks be inconspicuous. However, when the conventional No. 3 or No. 4 finish is used for sink top materials, etc., the surface roughness is large, so if you wipe it with a cloth or detergent, the deposits will remain as dirt in the polished surface. It could not be easily removed. To solve this problem, you can use a material with a small surface roughness, such as No. 7 finish, but since No. 7 finish is glossy, even a small amount of deposits may remain. Then, there was a problem that dirt was easily noticeable. In view of the fact that conventional polished stainless steel strips have had various problems in terms of stain resistance, the present invention provides a method for manufacturing polished stainless steel strips that does not have these problems. Industrially, in the manufacturing method of the present invention, cold rolling is followed by polishing, and then bright annealing and temper rolling are sequentially performed. Conventionally, polishing was generally performed after skin-pass rolling, but in the case of the present invention, it is performed before skin-pass rolling. This is because the polished surface is temper-rolled to crush large polished convex portions and make the polished surface uniform. In addition, in the conventional production of polished stainless steel strips, annealing and pickling were performed after cold rolling.
In the case of the present invention, bright annealing is performed instead, and this bright annealing is performed after polishing. This is because when annealing and pickling are performed in the manufacturing method of the present invention, the polishing grains are fine and the polishing grains become distorted, resulting in an uneven appearance.
In addition, when polishing is performed after bright annealing, the polished grains become rough.
In other words, immediately after cold rolling, the surface is work hardened and becomes harder, resulting in finer grains when polished. Polishing in the present invention is performed by passing a steel strip through a polishing line equipped with a plurality of belt polishers. When polishing, the first step is #120.
~ Polishing with 2 to 4 sanders equipped with endless belts with #320 abrasive grains to condition the surface, then as a second step, polishing with endless cork belts with #320 to #400 abrasive grains Polish with two or more machines to form polished marks. As shown in the cross section of FIG. 1, an endless cork belt has cork grains 3 glued onto a belt base material 1 with an adhesive 2, and an abrasive material 4 is glued. In the case of the present invention, as mentioned above, in the first stage, an endless belt with abrasive grains of #120 to #320 is used, but if a belt with abrasive grains coarser than #120 is used, later the abrasive grains of #320 to #400 are used. This is because even if the steel strip is sanded with an endless belt, coarse grinding marks remain, and if a belt with a finer count than #320 is used, multiple belt sanders are required to remove all the bare surface of the steel strip. . As for the number of belt sanders, even if an endless belt with the above particle size is used, it is impossible to remove the entire surface with one belt sander, so two belt sanders are required.
Requires more than one unit. However, if there are four machines, even if there are surface flaws, they can be removed, so a maximum of four machines is sufficient. On the other hand, in the second stage, an endless cork belt with abrasive grains of #320 to #400 is used because if the abrasive grains are coarser than #320, the abrasive grains will become coarse and it will be difficult to remove deposits. This is because if you use something thinner than #400, the gloss will be high and the removal marks of deposits will be noticeable. The reason why two or more belt sanders are used for polishing is that it is not possible to obtain a soft polished surface with one belt sander.
Normally, two machines are sufficient to obtain soft polishing marks, and if three machines are used, even better polishing marks can be obtained, but this increases the cost. It is preferable that the plate passing speed in the first and second stages of polishing be 10 to 50 m/min, and the belt circumferential speed be 900 to 2100 m/min. If the sheet threading speed and belt circumferential speed are faster than these, the length of the polishing stitches will become too short and the appearance will not be good.
On the other hand, if it is slow, the length of the polishing stitches becomes too long, which not only results in poor appearance but also reduces productivity and increases costs. FIG. 2 shows an embodiment of a polishing method in a polishing line, in which a coil 6 of a steel strip 5 is set on a payoff reel 7, from which the steel strip 5 is sent out.
The steel strip 5 sent out from the payoff reel 7 is corrected in shape by a leveler 8, then connected to the preceding steel strip by a welder 9, and passed through a belt grinder. For polishing, there are four belt sanders 10 on the entry side.
#120 to #320 for a, 10b, 10c and 10d
Endless belt with abrasive grains 11a, 11b, 1
Attach 1c and 11d and polish them while rotating. Endless cork belts 12a and 12b with abrasive grains of #320 to #400 are attached to the next belt polishers 10e and 10f for polishing. In the figure, 13 is a breaker roll, 14 is a billy roll for bending the steel strip 5, and 15 and 16 are contact rolls and idle rolls for rotating endless belts 11a to 11d or endless cork belts 12a and 12b. After being polished as described above, the steel strip 5 is wound onto a tension reel 18 while inserting a paper 17 to prevent interlaminar slippage, and cut by a shear 19 when the welded portion is reached. For bright annealing after polishing, conventionally known conditions are sufficient, and for temper rolling after bright annealing, conventionally known conditions, that is, a rolling reduction of 0.5 to 1.5%, are sufficient.
The steel strip produced in this manner may be passed through a normal shearing equipment to form a steel plate. Table 1 shows a belt sander in which a SUS304 hot-rolled steel strip is cold-rolled using a conventional method, then passed through a polishing line, and an endless belt with #320 abrasive grains is attached while passing the strip at a speed of 30 m/min. First, the surface is adjusted by polishing with four machines, then two belt polishers equipped with endless cork belts with #400 abrasive grains are used to polish and sharpen, and then bright annealing and rolling reduction are performed using conventional methods. Various substances shown in Table 2 were attached to the material of the present invention produced by 1.0% temper rolling and then further shearing, and the conventional polished material (including improved products. Both are SUS304) for 24 hours. After leaving it for a while, wash the surface once with soap water, once with tap water, twice with ethyl alcohol, and twice with acetone to remove it, then observe the dirt marks with the naked eye and judge according to the criteria in Table 3. The results are shown below.

【table】

【table】

【table】

[Table] As is clear from Table 1, the products produced according to the present invention have excellent stain resistance. In addition, the finishing material of the present invention in Table 1, No. 7 (commercially available material 1)
The surface roughness of the finishing material and No. 4 finishing material was approximately as follows.

[Table] Figure 3 shows surface photographs of the present invention material in Table 1 and No. 4 finishing material, where the present invention material is finer. As described above, it is easy to remove deposits from the polished stainless steel strips and steel plates manufactured according to the present invention, and the traces of deposits are not noticeable as stains.

[Brief explanation of drawings]

Fig. 1 is a schematic cross-sectional view of an endless cork belt, Fig. 2 shows an embodiment of the polishing method in the manufacturing method of the present invention, and Fig. 3 is a surface micrograph of the stainless steel belt in the embodiment. hand,
A indicates the finishing material of the present invention, and b indicates the No. 4 finishing material. The magnification is 200x in both cases. 1... Belt base material, 2... Adhesive, 3... Cork grains, 4... Abrasive material, 5... Steel strip, 6... Coil,
7...Payoff reel, 8...Leveler, 9...
Welding machine, 10a to 10f... Belt polishing machine, 11
a to 11d... Endless belt with abrasive grains of #120 to #320, 12a, 12b... Endless cork belt with abrasive grains of #320 to #400, 13... Breaker roll, 14... Billy roll, 15... Contact roll, 16...Idle role, 17...
...Interleaving paper, 18...Tension reel, 19...Sear.

Claims (1)

[Claims] 1. After cold-rolling the steel strip, it was passed through a polishing line equipped with a plurality of belt polishers, and as a first step, an endless belt with #120 to #320 abrasive grains was attached. Polishing is performed using 2 to 4 polishing machines, and then, as a second step, polishing is performed using 2 or more polishing machines equipped with endless cork belts with #320 to #400 abrasive grains. After completion of these polishing processes, bright annealing and A method for manufacturing polished stainless steel strip with excellent stain resistance, which is characterized by successive temper rolling. 2. Threading speed is 10 to 50 m/min, and circumferential speed of endless belt and endless cork belt is 900 to 50 m/min.
A method for producing a polished stainless steel strip with excellent stain resistance according to claim 1, characterized in that the strip is polished at a speed of 2100 m/min.