JPH0561089B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] This invention relates to a method for manufacturing plate-shaped products by rolling a polymeric material.

[Conventional technology]

It is known that polymeric materials are given high strength and excellent impact resistance by stretching by rolling. To obtain such a board,
For example, as shown in Fig. 4, in Japanese Patent Application No. 123435/1982 (Japanese Patent Application No. 280014/1983), tension reels 2 and 2' are installed before and after the rolling mill 1, and rolling is carried out while applying tension. A method is disclosed. In the figure, 3 indicates a material, 4 indicates a dummy coil, and 5 indicates a bolt. Furthermore, as shown in Fig. 5, Japanese Patent Application No. 1-91888 proposes a method in which the initial rolling pass is performed without tension, and the subsequent passes or the final pass are rolled while applying tension. . In the figure, 6 indicates a roll, 7 indicates a material, and 8 indicates a tension applying device.

However, even with these methods, there are still problems to be solved in terms of productivity, yield, etc.

[Problem to be solved by the invention]

In the process using the tension reel described above, holes are made in advance at the front and rear ends of the material, and after heating the material, the material is positioned directly under the opened roll, and a dummy coil on the tension reel and, for example, As shown in detail in FIG. 6, a method is adopted in which the rolls 12 are rolled down after the rolls 12 are fixed using holes such as bolts 14 to start rolling. In the figure, 13 indicates a material, and 15 indicates a dummy coil. However, in this method, it is necessary to prevent the fastening part from coming into contact with the roll, so the length L in the longitudinal direction of the unrolled part (the fastening part with the tension reel) reaches a maximum of 300 mm. After rolling, this part will be cut off, so
The proportion of the part that can be used as a product, the so-called yield, is extremely small, resulting in increased manufacturing costs.

On the other hand, in the method of rolling with no tension in the initial rolling pass and applying tension in the intermediate passes or the final pass, the yield is lower than that of the above method because the tension device is connected after the plate thickness becomes thin. Although it is improved, there are still some truncated parts.

In either case, the yield decreases because tension is ultimately applied to the material, but this is because, in the rolling of polymers, the elastic recovery after rolling is large. This is because applying tension to the material is an essential step in obtaining a flat plate.

In view of the above points, the present invention has been made with the object of providing a rolling method with low equipment cost and high yield.

[Means to solve the problem]

A feature of the present invention is that in a method of increasing the strength of a polymer material by stretching it in one direction or in a direction perpendicular to one direction by rolling a polymer material in multiple passes, tension is applied to all passes. The method of rolling a polymeric material is characterized in that the rolling process is performed without applying pressure, and after rolling, a warm pressure of 0.003 Kgf/cm ² or more is applied to the flat surface of the plate.

Hereinafter, the present invention will be explained in detail based on the drawings.

The equipment in Fig. 1 is a rolling mill 9 in Fig. a, a press machine 11 in Fig. C, and the former is b.
The latter is in charge of the rolling process to reduce the thickness of the plate as shown in the figure, and the latter is in charge of the process of correcting the flatness of the rolled plate as shown in figure c.

The inventors first experimentally confirmed the action and effect of tension in rolling a polymer in a rolling process. In other words, it has been found through many experiments that even if rolling is performed in multiple passes without tension, the shape deteriorates, but the original purpose of rolling, which is to reduce the plate thickness, can be achieved. Therefore, if the shape is ignored, a rolled material with a predetermined thickness can be obtained by a tensionless rolling process as shown in FIG. 1a.

In this case, rolling the material without tension in the initial pass means that the biting property is reduced, but this is because the material is rolled in advance as proposed in Japanese Patent Application No. 1-91888. Rolling may be started from a state in which the intermediate portion in the longitudinal direction is rolled down with a roll.

Next, the inventors experimentally confirmed the effects of temperature and pressure on the rolled material in the straightening process.
That is, we have found through many experiments that by applying warm pressure to the flat surface of a thin rolled plate whose shape has deteriorated after rolling, it is possible to straighten a thin rolled plate whose shape has deteriorated to a sufficiently satisfactory shape.

Here, the shape was evaluated using the steepness λ used in the steel field. The definition of steepness λ is as follows, and the wave height δ and pitch l in the following formula are shown in FIG.

Steepness λ=δ/l From this, the relationship between the shape (steepness) and pressure in polypropylene, for example, is as shown in Figure 3,
It can be seen that a flat plate can be obtained by applying a pressure of 0.003 Kgf/cm ² .

Therefore, if pressure is applied to a plate with a poor shape after rolling using a press machine 11 as shown in FIG. 1c, a rolled plate 10 with excellent flatness as shown in FIG.
can get. Since the pressure to be applied may be a very small value, the press 11 does not require any particular power to generate the pressure, and for example, the weight of the aluminum plate is sufficient.

As shown above, in the present invention, there is no need to use tension, so there is no cutting off of the fastening parts as shown in FIG. 6, and the rolled plate with excellent flatness can be
Manufacture is possible with a product yield of 100%. In addition, when rolling in two directions, this manufacturing method can be used for rolling in the first direction, and can also be used for rolling in the next direction.

〔Example〕

A polypropylene material with a plate thickness of 10 mm, a plate width of 1000 mm, and a length of 1000 mm is rolled in 4 passes without tension from the beginning to a plate thickness of 3 mm using rolls with a roll diameter of 300 mm.
When the flat press part was pressed using a warm press made of aluminum at a pressure of 0.005 Kgf/mm ² and a temperature of 137.5°C for 30 minutes, a rolled plate with a satisfactory shape was obtained. The yield at this time was 100%.

[Comparative example]

A polypropylene material with a thickness of 10 mm, a width of 1000 mm, and a length of 1000 mm is rolled with rolls with a roll diameter of 300 mm for 3 passes without tension from the beginning.The front and back edges of the plate are fastened together by friction force, and then rolled again while applying tension. It was rolled and the fastening portion (300 mm x 2) was cut off. The yield at this time was 80%.

[Effects of the Invention] As described above, according to the present invention, it is possible to roll a polymeric material with a high yield using inexpensive equipment, and therefore, there is an effect that an excellent polymeric material can be mass-produced.

[Brief explanation of the drawing]

Figures 1 a, b, c, and d are diagrams showing the manufacturing process of the rolled plate of the present invention, Figure 2 is a diagram showing the definition of steepness, and Figure 3 is a diagram showing the relationship between steepness and pressure in polypropylene. , Fig. 4 is a diagram showing a tension reel method, which is an example of a conventional manufacturing process for a rolled polymer plate, and Fig. 5 a, b, c, and d are examples of a conventional manufacturing process for a rolled polymer plate. FIG. 6 is a diagram showing a rolling method in which tension is applied only in the final pass, and FIG. 6 is a diagram showing a state in which the material is fastened to a tension reel in order to apply tension. 1... Roll, 2... Tension reel, 3... Material, 4... Dummy coil, 5... Bolt, 6... Roll, 7... Material, 8... Tension adding device, 9... Rolling machine,
10...Material, 11...Press machine, 12...Roll, 1
3...Material, 14...Volt, 15...Dummy coil.

Claims (1)

[Claims] 1 A method of increasing the strength of a polymeric material by stretching it in one direction or in a direction perpendicular to one direction by rolling multiple passes, in which all passes are rolled without applying tension, and the rolling Afterwards, warmly
A method of rolling a polymer material, which is characterized by applying a pressure of 0.003 Kgf/cm ² or more to the flat surface of a plate.