KR20200065681A - Composition for sealing member of continuous steel plate passing apparatus and continuous steel plate passing apparatus comprising the same - Google Patents

Abstract

The present invention relates to a composition for a sealing member of a continuous steel sheet passing apparatus, comprising: 60 to 75 wt% of a fluorine compound; and 25 to 40 wt% of a carbon compound. According to the present invention, the sealing member of a continuous steel sheet passing apparatus has excellent lubricity and sealing properties.

Description

Composition for sealing member of steel sheet continuous mailing device and steel sheet continuous mailing device including the same TECHNICAL FIELD

The present invention relates to a composition for a sealing member of a continuous steel sheet mailing device and a continuous steel sheet mailing device comprising the same.

Air-to-air type roll-to-roll vacuum deposition process equipment uses plasma vapor deposition (CVD) or chemical vapor deposition (CVD) technology on the surface of a steel strip that is transported in vacuum. It is a device for vacuum pre-treatment for surface activation or functional coating layer of metal or organic matter by vacuum deposition.

The method of transferring the steel sheet into the vacuum deposition facility is to unwind the steel sheet strip rolled in the form of a coil in the atmosphere and pass the steel sheet strip mailing device. Subsequently, in the vacuum deposition process facility, the surface of the steel sheet is activated by plasma surface treatment, the surface coating by PVD or CVD vacuum deposition process, post-treatment, and the cooling process are transferred to the atmosphere through a continuous steel plate strip mailing device.

As described above, the continuous steel strip mailing device can continuously transport the steel strip to the vacuum in the air or to the air in the vacuum without cutting, which is realized through a multi-stage sealing mechanism, gradual differential pressure, and vacuum exhaust.

U.S. Registered Patent #5192585

An object of the present invention is to provide a composition for a sealing member of a steel plate mailing device that is excellent in lubricity and sealability, does not soften or deteriorate at high temperatures, and can maintain strength despite pressure differences.

In addition, it is to provide a steel plate mailing device that does not deteriorate lubricity and sealability even when used for a long period of time and has a low rotation load factor.

According to one embodiment of the present invention, there is provided a composition for a sealing member of a continuous sheet-rolling apparatus for a steel sheet comprising 60 to 75% by weight of a fluorine compound and 25 to 40% by weight of a carbon compound.

The fluorine compound is PTFE (Poly tetrafluoroethylene) FEP (Fluorinated ethylene propylene) PFA (Perfluoroalkoxy alkane), ETFE (Ehtylene tetrafluoroethylene), CTFE (Chloro-trifluoro-Ethylene), PVdF (Poly vinylidene fluoride) and PVF (Poly vinyl fluoride) It is one or more compounds selected from the group consisting of.

The fluorine compound has a melting point of 170 to 330°C, and a dynamic friction coefficient of 0.1 to 0.5.

The carbon compound is selected from the group consisting of carbon nanotube, graphene, graphene oxide, graphite, carbon fiber, and carbon black. It is a species or more compounds.

According to another embodiment of the present invention, there is provided a continuous steel plate mailing apparatus including a seal and a sealing roll comprising the composition for a sealing member.

The sealing roll has a rotation load factor of 50% or less.

The present invention can manufacture a steel sheet mailing device having excellent sealing properties and lubricity by using a composition for a sealing member containing a fluorine resin and a carbon compound in a specific content ratio. In addition, it is excellent in heat resistance, and it has a low rotational load rate even in long-term use, and can prevent surface defects of the steel sheet due to slip phenomenon.

1 is a schematic view of a continuous steel plate mailing apparatus according to the present invention.
Figure 2 shows an SEM image of the graphite powder as an example of the carbon compound.

Hereinafter, preferred embodiments of the present invention will be described. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below.

The present invention relates to a sealing member applicable to a steel sheet continuous mailing device (hereinafter, also referred to as a "mailing device").

Generally, the mail order device is for realizing an air-to-air type roll-to-roll vacuum process for a steel strip, an upper sealing roll (20), a lower sealing roll (30), and a side seal ( Side Seal) 40, an upper seal 50, a lower seal (not shown), and a side seal housing (Side Seal Housing) 60. In the present invention, the sealing member means an upper seal 50, a lower seal, and a side seal 40 that are in close contact with the sealing roll 20 that rotates for the mailing of the steel strip to block ingress of outside air. .

The upper and lower portions of the steel strip are in contact with the circumferential surfaces of the upper sealing roll 20 and the lower sealing roll 30, respectively, and the upper and lower portions of the sealing roll are respectively connected to the upper seal 50 and the lower seal. Thereby, the left and right sides of the sealing roll are blocked by external air by the side seal 40 to form a vacuum. In other words, the upper seal 50, the lower seal, and the side seal 40 are in close contact with the circumferential surface of the sealing roll, and the area of the gap through which air can move is very small except for mechanical tolerances.

In order to maintain the vacuum state continuously when mailing, the sealing roll of the mailing device must be in close contact with the upper and lower portions of the steel strip. In addition, while the sealing roll is rotating, the upper and lower seals and side seals 40 must continuously seal the sealing roll. When the sealing roll rotates for mail order while the upper and lower seals and the side seals 40 are in close contact with the sealing rolls, the surfaces of the upper and lower seals and the side seals 40 can be easily worn by friction, and air moves to the worn parts. The differential pressure can be destroyed.

According to the present invention, there is provided a composition for a sealing member for a continuous sheet of steel sheet in which a fluorine compound and a carbon compound are mixed, and when a seal is produced using the composition, a seal having excellent physical properties such as lubricity and wear resistance can be produced. The fluorine compound preferably has a melting point of 170 to 330°C and a dynamic friction coefficient of 0.1 to 0.5 (7kg/cm ² ). By using a fluorine compound having the above characteristics, even when a high-temperature steel sheet strip is passed through, the surface of the sealing roll does not melt well, and the lubrication is excellent, thereby maintaining adhesion.

Examples of the fluorine compound include polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP) perfluoroalkoxy alkane (PFA), ethylen tetrafluoroethylene (ETFE), chloro-trifluoro-ethylene (CTFE), polyvinylidene fluoride (PVDF), and polyvinyl fluoride (PVF). One or more compounds selected from the group consisting of can be used, it is preferable to use a PTFE resin having the highest melting point and the lowest coefficient of dynamic friction among the fluorine compounds exemplified above.

On the other hand, as the carbon compound, graphite (Graphite), carbon nanotube (Carbon nanotube), graphene (Graphene), graphene oxide (Graphene Oxide), carbon fiber (Carbon fiber) or carbon black (Carbon black) and the like can be used It is possible to use graphite from the viewpoint of improving the strength of the yarn and economical.

The composition for a sealing member for a continuous mailing apparatus of a steel sheet of the present invention contains 60 to 75% by weight of a fluorine compound based on the total weight of the composition. The fluorine compound is used as a binder to impart lubricity when applied to a seal and to maintain sealing properties with a steel strip, and when the fluorine compound is contained in excess of 75% by weight, the lubricity of the seal becomes insufficient and friction with the steel strip By this, the surface is abraded, and the sealing property with the steel strip can be deteriorated. In addition, by causing the temperature of the seal to rise due to frictional heat and the resulting reduction in strength, a load is generated in the rotational power of the sealing roll, and the motor for rotating power of the sealing roll can be stopped. If the rotational power load ratio exceeds 50%, slip occurs between the steel strip and the sealing roll due to mismatch between the rotation speed of the sealing roll and the mailing speed, and a fine scratch may occur on the surface of the steel strip.

On the other hand, when the content of the fluorine compound is less than 60% by weight, since the content of the carbon compound is relatively increased, the strength of the yarn may increase, but the performance of the binder is not properly exhibited, and thus, the molding of the yarn is difficult and the product is brittle during use. Problems such as a decrease in vacuum differential pressure performance may occur.

On the other hand, the composition for a sealing member for a continuous sheet of steel sheet may include 25 to 40% by weight of a carbon compound based on the total weight of the composition. When the content of the carbon compound is within the above range, the strength and hardness of the yarn are sufficiently secured to sufficiently withstand the pressure difference between the vacuum inside and the atmosphere outside, thereby providing excellent sealing power. In addition, the friction coefficient can be reduced to ensure lubricity, and the amount of wear on the seal is reduced to allow continuous mailing for a long time, and the load factor for rotation of the sealing roll can be maintained at 50% or less.

However, if the content of the carbon compound is less than 25% by weight, lubricity and heat resistance are weakened, and the surface temperature of the sealing roll may be increased due to friction. When the surface temperature of the sealing roll rises to 50°C or higher, the seal softens, and the frictional force between the seal and the sealing roll becomes higher, and the rotation load ratio of the roll rises to 70% or more, causing surface bonding due to slip, and eventually mailing Interruptions can occur. On the other hand, when the content of the carbon compound exceeds 40% by weight, the content of the fluorine compound is relatively reduced, so it is brittle and the moldability decreases, so that the production of the yarn may be difficult.

The composition for sealing members of the present invention may further include glass fibers to improve strength and lubricity.

The present invention provides a continuous steel plate mailing apparatus including a sealing member to which the composition for a sealing member is applied. The sealing roll of the steel sheet continuous mailing device represents a rotational load factor of 50% or less, and preferably may be 30% or less. In addition, since the wear resistance is improved, the sealing property does not deteriorate even when mailing continuously for a long period of time, thereby minimizing air inflow.

Example

Hereinafter, embodiments of the present invention will be described in detail. The following examples are only for understanding the present invention and are not intended to limit the present invention.

<Example 1>

A composition for a sealing member was prepared by mixing 375 g of PTFE resin and 125 g of graphite powder using a mechanical mixer. Thereafter, heat was applied to form a plate, and a thread was manufactured through mechanical processing.

<Example 2>

Compositions and seals were prepared in the same manner as in Example 1, except that 350 g of PTFE resin and 150 g of graphite powder were used.

<Example 3>

Compositions and seals were prepared in the same manner as in Example 1, except that 325 g of PTFE resin and 175 g of graphite powder were used.

<Example 4>

A composition and a seal were prepared in the same manner as in Example 1, except that 300 g of PTFE resin and 200 g of graphite powder were used.

<Comparative Example 1>

Compositions and seals were prepared in the same manner as in Example 1, except that 425 g of PTFE resin and 75 g of graphite powder were used.

<Comparative Example 2>

Compositions and seals were prepared in the same manner as in Example 1, except that 400 g of PTFE resin and 100 g of graphite powder were used.

<Comparative Example 3>

Compositions and seals were prepared in the same manner as in Example 1, except that 275 g of PTFE resin and 225 g of graphite powder were used.

<Experimental Example>

Compressive strength, hardness, friction coefficient of the compositions prepared in Examples and Comparative Examples, and rotation load rates according to the temperature of the sealing rolls are measured and are shown in Table 1 below.

1. Compressive strength (kgf/cm ² )

The compressive strength of the yarn was measured using a universal test machine.

2. Hardness (Durometer)

The hardness of the yarn was measured using a Durometer, a spring-type hardness tester.

3. Friction coefficient

The relative force ratio was measured by rotating and rubbing the thread against the friction surface of the reference material.

4. Rotation load factor

The load rate of the motor rotating the sealing roll was measured by measuring the current supplied to the steel sheet continuous mailing device.

PTFE
content
(weight%) Graphite content
(weight%) Compressive strength
(kgf/cm ² ) Hardness
(Durometer) Coefficient of friction Rotation load factor
(Heat resistance, %) <50℃ >50℃ Example 1 75 25 105 64 4.2 E ^-3 <30 <50 Example 2 70 30 107 65 2.0 E ^-3 <30 <50 Example 3 65 35 108 66 1.4 E ^-3 <20 <50 Example 4 60 40 106 67 1.0 E ^-3 <20 <30 Comparative Example 1 85 15 104 63 6.7 E ^-3 <50 >70 Comparative Example 2 80 20 104 63 4.5 E ^-3 <50 >70 Comparative Example 3 55 45 - - - - -

As in Examples 1 to 4, when the yarn was prepared using a composition containing PTFE and graphite in a specific range, the compressive strength and hardness of the yarn were excellent, and the friction was reduced, so that the surface of the yarn was not easily worn. In addition, it can be seen that in Examples 1 to 4, the rotation load ratio was maintained at 50% or less regardless of the surface temperature of the sealing roll.

In Comparative Examples 1 and 2, since the content of graphite was small, the friction coefficient of the sealing roll was not sufficiently reduced, resulting in a high rotation load ratio. In addition, in the case of Comparative Examples 1 to 3, it can be seen that when the surface temperature of the sealing roll exceeds 50°C, the rotation load rate has increased rapidly to 70% or more.

10 steel strip
20 Upper sealing roll
30 lower sealing roll
40 side seal
50 upper thread
60 side seal housing

Claims (6)

A composition for sealing members of a steel sheet continuous mailing apparatus comprising 60 to 75% by weight of a fluorine compound and 25 to 40% by weight of a carbon compound.
According to claim 1,
The fluorine compound is polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), perfluoroalkoxy alkane (PFA), ethylentetrafluoroethylene (ETFE), chloro-trifluoro-ethylene (CTFE), polyvinylidene fluoride (PVDF), and polyvinyl fluoride (PVF). A composition for a sealing member of a continuous steel plate mailing device, which is at least one compound selected from the group consisting of.
According to claim 1,
The fluorine compound has a melting point of 170 to 330°C, and a dynamic friction coefficient of 0.1 to 0.5.
According to claim 1,
The carbon compound is selected from the group consisting of carbon nanotube, graphene, graphene oxide, graphite, carbon fiber, and carbon black. A composition for sealing members of a steel sheet continuous mailing device which is a compound of more than one kind.
A steel sheet continuous mailing apparatus comprising a seal and a sealing roll comprising the composition for a sealing member according to any one of claims 1 to 4.
The method of claim 5,
The sealing roll is a continuous steel plate mailing device having a rotation load ratio of 50% or less.

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