KR100560670B1 - Apparatus for manufacturing heat shrinkable tube having porous expansion tube - Google Patents

Abstract

The present invention relates to an expansion device including an expansion tube used to expand a heat shrink tube, and in particular, by spraying a coolant to the porous expansion tube to form a water film between the expansion tube and the tube to reduce the friction between the expansion tube and the tube and The present invention relates to an expansion device for manufacturing a heat shrink tube having a porous expansion tube for producing a heat shrink tube having a constant quality with a low elongation in the longitudinal direction of the heat shrink tube.

Heat Shrink, Tube, Expansion Tube, Porous, Water Membrane, Elongation, Coolant, Filter

Description

Expansion apparatus for manufacturing heat shrinkable tube having porous expansion tube {APPARATUS FOR MANUFACTURING HEAT SHRINKABLE TUBE HAVING POROUS EXPANSION TUBE}

1 is a cross-sectional view of a conventional expansion device for manufacturing a heat shrink tube.

Figure 2 is a cross-sectional view of the expansion device for producing a heat shrink tube having a porous expansion tube according to the present invention.

Figure 3 is an explanatory view showing a cooling water path in the expansion device for producing a heat shrink tube having a porous expansion tube according to the present invention.

Figure 4 is an explanatory view showing the principle of expansion in the expansion device for producing a heat shrink tube having a porous expansion tube according to the present invention.

Figure 5 is a cross-sectional view showing the ultrasonic vibration device attached to the expansion device for manufacturing a heat shrink tube having a porous expansion tube according to the present invention.

<Explanation of symbols on main parts of the drawings>

1, 101: heat shrink tube 2, 102: expansion chamber

3, 103: vacuum pump 4, 104: vacuum inlet

5, 105a: coolant nozzle 105b: coolant inlet

6, 106: Caterpillar 8, 108a: cooling water pump

108b: coolant filter 109a: bobbin

109b: pressure tube 10, 110: heat shrink tube expansion device

11, 111: expansion tube 111: porous expansion tube

12, 112: Teflon adapter 13, 113: expansion tube hole

121a: Expansion chamber outer wall 121b: Expansion chamber inner wall

The present invention relates to an expansion device including an expansion tube used to expand a heat shrink tube, and in particular, by spraying coolant to the porous expansion tube to form a water film between the expansion tube and the tube to reduce the friction between the expansion tube and the tube The present invention relates to an expansion device for manufacturing a heat shrink tube having a porous expansion tube for producing a constant quality heat shrink tube having a small elongation in the longitudinal direction of the heat shrink tube and a small elongation variation.

In general, a heat shrink tube refers to a polymer synthetic resin product in the form of a tube that contracts at a predetermined rate when heat is applied.

The polymer synthetic resin, which is the material of the heat shrink tube, is a thermoplastic resin. Thermoplastic resin is composed of a very long and thin irregular array of molecules to form crystals in the overlapping molecules, which is a material having a binding force between molecules.

After heating, the thermoplastic material cools and the crystal remains regenerated. The transmission of high-energy radiation to the regenerated material thus creates permanent bridges between adjacent molecules. The crosslinked material is flexible and does not melt even when heated above the melting point of the crystal.

In particular, the material having a crosslinked structure has elastic memory properties that memorize the shape before deformation. Due to this elastic memory property, the heat shrink tube can be contracted from 25% to 75% in the radial direction and within 10% in the longitudinal direction depending on the product to be manufactured.

As described above, the contracted heat shrink tube is closely adhered to the product to be manufactured and is used for insulation protection, corrosion protection, and the like of the product.

In the conventional heat-shrink tube expansion process, the apparatus unit includes a heating unit for deformably heating the tube, an expansion and cooling unit for expanding and cooling the heated tube, a caterpillar unit for applying a predetermined attraction force to pull out the expanded and cooled tube, And a bobbin unit for mounting the finished product. The portion of the apparatus which has the greatest influence on the quality after the expansion of the heat shrink tube is the expansion cooling portion for expanding and cooling the tube. In general, a method of processing the tube by passing the expansion tube mounted in the expansion chamber is described. Take it.

1 is a cross-sectional view of a conventional expansion device for manufacturing a heat shrink tube. As shown in FIG. 1, the expansion device 10 for manufacturing a conventional heat shrink tube 10 includes an expansion chamber 2 having a configuration for expanding and cooling the heat shrink tube 1 and a plurality of expansion tube holes 13 in the expansion chamber 2. It includes an expansion tube (11) having a).

The expansion chamber 2 has a coolant nozzle 5 and a vacuum suction port 4 on the outer wall for cooling and expansion of the heat shrink tube 1, respectively. The coolant nozzle 5 is connected to the coolant pump 8, and the vacuum inlet 4 is connected to the vacuum pump 3.

In addition, an expansion tube 11 is provided inside the expansion chamber 2 to substantially contact the tube. In the expansion tube 11, an expansion tube hole 13, which is a passage of the pressure transmitted through the vacuum suction port 4 and the cooling water sprayed through the cooling water nozzle 5, is constantly arranged.

A teflon adapter 12 is arranged at the inlet through which the tube 1 enters the expansion chamber 2. At the position beyond the exit from which the tube 1 exits the expansion chamber 2, a caterpillar 6 for pulling the tube 1 is arranged.

Operation of the heat shrink tube expansion chamber (2) having the above configuration is made as follows.

First, the tube before expansion is heated to a temperature of about 100 to 200 ° C through a heating roll, and then passes through a Teflon adapter 12 installed at the entrance to the expansion tube 11 of the tube. This Teflon adapter 12 should be able to minimize friction with the tube 1. To this end, a space is formed between the Teflon adapter 12 and the tube 1 in which a small amount of air can leak. Accordingly, the Teflon adapter 12 and the tube 1 do not directly rub, so that the tube 1 may enter the expansion tube 11 relatively smoothly.

On the other hand, the vacuum suction port 4 provided on the outer wall of the expansion chamber 2 is connected to the vacuum pump (3). The vacuum pump 3 is a device that can suck a predetermined gas to lower the pressure around. As a result, the pressure in the expansion chamber 2 drops, and the vacuum force acts on the inside of the expansion tube 11 in the radial direction of the expansion tube hole 13 by the pressure dropped in the expansion chamber 2. According to this vacuum force, the heat shrink tube made of the thermoplastic resin can expand. The expanded tube proceeds in close contact with the inner diameter of the expansion tube 11, and thus, the size of the tube to be manufactured varies depending on the inner diameter of the expansion tube 11.

The coolant 7 is sprayed into the expansion chamber 2 through the coolant nozzle 5 by the pressurizing action of the coolant pump 8. The sprayed coolant 7 enters the expansion tube 11 through the expansion tube hole 13 and comes into contact with the outer surface of the tube 1. The tube 1 which has been heated prior to entering the expansion tube 11 by the heat transfer between the cooling water 7 and the tube 1 can be cooled.

As described above, the heat shrink tube 1 may be simultaneously expanded and cooled while passing through the expansion tube 11. In this case, as shown in FIG. 1, expansion occurs mainly at the upper portion of the expansion tube 11, and cooling occurs mainly at the middle and lower portions of the expansion tube 11.

As mentioned above, the heat-shrinkable tube 1 which has been expanded and cooled with a predetermined diameter is edged by the caterpillar 6.

In accordance with the expansion in the expansion chamber (2), the tube (1) is in close contact with the inner wall of the expansion tube (11) proceeds in the longitudinal direction. In this case, the friction force acts on the tube 1 in a direction opposite to the direction in which it is to be manufactured. Although the tube 1 is cooled by the temperature of the cooling water, some time is required for the tube 1, which was approximately 100 ° C. to 200 ° C. in the initial state, to be cooled down. When the friction force acts on the tube 1, the tube 1 can be easily deformed into a shape having a bend in the longitudinal direction, and the elongation length and thus elongation of the heat shrinkable tube can be increased. In addition, when the cooling of the heat shrink tube is not sufficiently performed, the elongation length and thus the elongation may be increased by the deformation of the heated tube.

In the case of heat-shrink tube having a high elongation at the time of manufacture of the product, especially when used in an electronic component such as an electric wire, short-circuit or short circuit may occur because it may be formed in a shorter length in the longitudinal direction than the length expected by the manufacturer after shrinking.

In addition, in the case of high-speed expansion, the contact surface between the expansion tube and the tube is relatively increased, thereby increasing the frictional force, thereby increasing wear of the expansion tube and shortening the life of the expansion tube.

In addition, when increasing the tube production speed, the difference in the length of stretching according to the above cause is further increased, there is a limit that can not increase the production speed. This is particularly limited in the case of a large diameter tube to cool the whole uniformly, the larger the size of the tube, the faster the production speed is limited.

The present invention is to solve the above problems, the first object of the present invention in the expansion device for producing a heat shrink tube having a porous expansion tube by spraying a cooling water to the porous expansion tube to form a water film between the expansion tube and the tube It is to provide an expansion device for manufacturing a heat shrink tube to reduce the friction between the expansion tube and the tube and to reduce the elongation in the longitudinal direction of the tube.                         

It is a second object of the present invention to provide an expansion device for manufacturing a heat shrink tube which increases the cooling effect of a tube by cooling a tube surface of a preheated thermoplastic resin material which is not completely cooled after heating by forming a water film between the expansion tube and the tube. It is.

The objects of the present invention are within the expansion chamber 102 and the expansion chamber 102 connected to the cooling water pump 108a for pressurizing and spraying the cooling water and the vacuum pump 103 for inhaling the gas to lower the pressure of the suctioned space. It is achieved by an expansion device for manufacturing a heat shrink tube, characterized in that it comprises an expansion tube 111 is arranged porous so that the cooling water can be introduced by a capillary phenomenon.

Here, it is preferable that the expansion chamber 102 has a shape in which the inside thereof is divided by the inner wall surface 121b in the longitudinal direction of the expansion chamber 102.

In addition, the cooling water inlet 105b, which is an inlet connected to the cooling water pump 108 and sprays the cooling water into the expansion chamber 102, is preferably installed in the space between the inner wall surface 121b of the expansion chamber and the expansion pipe 111. Do. In addition, it is preferable that a plurality of coolant inlets 105b are formed, and the space between the inner wall surface 121b of the expansion chamber and the expansion tube 111 is divided into a space in which each coolant inlet 105b is formed.

In addition, in order to discharge the cooling water sprayed to the expansion tube 111 from the expansion tube 111 and to transfer the pressure of the vacuum pump 103, the inside of the expansion tube 111 and the inner wall surface of the expansion chamber 102 ( The expansion tube hole 113 is preferably further connected to connect the space between the 121b) and the outer wall surface 121a. Here, the expansion tube hole 113 is preferably disposed at regular intervals in the longitudinal direction of the expansion tube (111).                         

Furthermore, it is preferable to further include a coolant filter 108b between the coolant pump 108a and the expansion chamber 102.

In order to increase the cooling water absorption efficiency of the porous expansion tube according to the present invention, it is preferable to further include an ultrasonic vibration device (150) attached to the manufacturing direction entrance of the heat shrink tube of the expansion tube (111) and converts the power into ultrasonic vibration. In particular, the ultrasonic vibration device 150 is preferably a piezoelectric element.

The temperature of the cooling water sprayed to cool the tube is preferably in the range of 0 ° C to 20 ° C.

Other objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and the preferred embodiments associated with the accompanying drawings.

Hereinafter, with reference to the accompanying drawings, an expansion device for manufacturing a heat shrink tube having a porous expansion tube according to the present invention will be described in detail.

Figure 2 is a cross-sectional view of the expansion device for producing a heat shrink tube having a porous expansion tube according to the present invention. As shown in FIG. 2, the expansion device 110 for manufacturing a heat shrink tube having a porous expansion tube according to the present invention is a cooling water pump 108a for pressurizing and spraying cooling water and a vacuum for inhaling gas and lowering a pressure of a suction space. An expansion chamber 102 connected to the pump 103 and a porous expansion tube 111 disposed in the expansion chamber 102 so that the sprayed cooling water may be introduced by the capillary phenomenon.

The expansion chamber 102 has a wall structure of an outer wall surface 121a which is an outer boundary of the expansion chamber 102 and an inner wall surface 121b that divides the space in the expansion chamber 102 in the longitudinal direction in the outer wall surface 121a.

On the outer wall surface 121a of the expansion chamber 102, a coolant nozzle 105a and a vacuum suction port 104 are provided for cooling and expanding the heat shrink tube 101, respectively. The coolant nozzle 105a is connected to a coolant pump 108a which pumps the coolant through a pressure difference. At this time, between the cooling water pump 108a and the cooling water nozzle 105a, a cooling water filter 108b for purifying the cooling water is disposed in order to prevent the porous space of the expansion tube 111 for manufacturing the porous heat shrink tube according to the present invention. The vacuum suction port 104 is connected to a vacuum pump 103 which is a device that sucks gas inside the expansion chamber 102 at a vacuum pressure.

The inner wall surface 121b of the expansion chamber 102 has an outer portion through the inner wall surface 121b of the coolant inlet 105b and the inner wall surface 121b, which is an incident part of the coolant which is directed therein through the inner wall surface 121b of the expansion chamber 102. An expansion pipe hole 113, which is a discharge passage of the cooling water toward the air passage and is a passage for vacuum pressure air, is disposed.

Meanwhile, the Teflon adapter 112 is disposed at the inlet through which the tube 101 enters the expansion chamber 102. A caterpillar 106 composed of a plurality of rollers that exerts a pulling force on the tube while the tube 101 exits the expansion chamber 102 and proceeds through the outlet is arranged in the circumferential direction of the tube 101. After passing through the caterpillar 106, the tube 101 is wound around a roll-shaped bobbin 109a, which can be wound around the tube. In the central axis of the bobbin 109a is disposed a pressure tube 109b connected to a device that is fitted inside the tube and pressurized. In the drawings illustrating the present invention, the bobbin 109a is represented to be much smaller than the actual shape, in order to express in detail the shape of the heat shrink tube 101 according to the present invention.

Inside the expansion chamber 102 is provided a porous expansion tube 111 that is in contact with the tube substantially. Between the porous expansion pipes 111, expansion pipe holes 113, which are discharge passages of cooling water and passages of vacuum pressure air, are regularly arranged. The space between the inner wall surface 121b and the outer wall surface 121a of the porous expansion tube 111 and the expansion chamber 102 is connected through the expansion tube hole 113.

Figure 3 is an explanatory view showing a cooling water path in the expansion device for producing a heat shrink tube having a porous expansion tube according to the present invention. As shown in FIG. 3, the coolant is sprayed into the expansion chamber 102 by pressurization to the coolant pump 108a. The cooling water discharged from the cooling water pump 108a is preferably in the range of 0 ° C to 20 ° C. This is because if the temperature of the cooling water is too low, it is cooled too quickly before the expansion of the heat shrink tube, and if the temperature of the cooling water is too high, the elongation of the tube increases due to incomplete cooling of the heat shrink tube.

First, the coolant pumped from the coolant pump 108a passes through the coolant filter 108b before being sprayed into the expansion chamber 102. The cooling water filter 108b is a filter having a filter diaphragm made of a porous medium or a plate therein, or is composed of a filter for removing unnecessary components by using an ion exchanger.

The coolant 131 in which foreign matter is filtered through the coolant filter 108b is annularly incident into the space in the inner wall surface 121b of the expansion chamber 102 through the coolant inlet 105b. For even distribution of the coolant, a coolant inlet 105b may be fitted with a sprayer-type device having holes lattice-shaped.

The coolant incident in an annular shape is attached to the outer wall surface of the expansion tube 111 formed in a porous manner according to the present invention and proceeds in the direction of reference 132 toward the inner wall surface of the expansion tube 111 by the capillary phenomenon of the fluid. Here, the amount of cooling water flowing may be adjusted according to the distance between the porous materials. However, when the gap between the porous material is too far, the gap between the porous material is manufactured by paying attention to the weakening of the capillary phenomenon.

The coolant that has advanced to the inner wall surface of the expansion tube 111 by the capillary phenomenon forms a water film 133 between the inner wall surface of the expansion tube 111 and the expanded heat shrink tube 101.

The water film 133 formed as described above may generate heat transfer between the heat shrink tube 101 heated to a predetermined temperature to cool the heat shrink tube 101. In addition, the heat shrink tube 101 may directly reduce the area in contact with the expansion tube 111, the friction may be reduced by the lubrication action of the water film 133 between the heat shrink tube 101 and the inner wall surface of the expansion tube 111. .

Cooling water that forms a water film and cools the tube to some extent is discharged in the direction of reference numeral 134 through the expansion tube hole 113 in a state where the temperature is relatively higher than when it is first sprayed.

Figure 4 is an explanatory view showing the principle of expansion in the expansion device for producing a heat shrink tube having a porous expansion tube according to the present invention. As shown in FIG. 4, gases between the outer wall surface 121a of the expansion chamber 102 and the inner wall surface 121b are vacuumed through the vacuum suction hole 104 formed in the outer wall surface 121a of the expansion chamber 102. It is sucked into the vacuum suction port 104 along the direction of the force 141. Due to the flow of gas sucked through the vacuum suction port 104, the pressure in the space between the outer wall surface 121a and the inner wall surface 121b of the expansion chamber 102 is lowered, and is continuously formed in the expansion pipe 111. The gas existing in the expansion tube hole 113 is also sucked out of the expansion tube hole by the suction force 142 in the expansion tube hole 113. By this action, in the expansion tube hole 113 formed in the expansion tube 111, the pressure acts toward the outside from the inside of the expansion tube 111, as a result of which the tube 101 can expand.

In this case, in order to facilitate expansion of the tube 101, the internal tube pressure 143 may be applied to the inside of the tube 101. The tube internal pressure 143 is applied through the pressure tube 109b which is connected to the central axis of the bobbin 109a winding the tube 101 while finally rotating the tube 101 to apply pressure to the inside of the tube 101. Here, the pressure pipe 109b is connected to a compressor (not shown) capable of injecting air.

The pressure 144 directed radially outward is applied to the inside of the tube 101 by the suction force 142 in the expansion tube hole 113 and the tube internal pressure 143 applied directly in the tube.

The inner tube pressure 143 is less affected by the number of times the tube 101 is wound on the bobbin 109a since the influence on the pressure 144 acting radially outward is reduced as the tube 101 to be manufactured is wound more. Increase in proportion.

Figure 5 is a cross-sectional view showing the ultrasonic vibration device attached to the expansion device for manufacturing a heat shrink tube having a porous expansion tube according to the present invention. As shown in Figure 5, the expansion tube 111 for manufacturing a heat shrink tube having a porosity according to the invention ultrasonic vibration device 150 that can vibrate the expansion tube to a vibration source having a high frequency through the ultrasonic vibration of the expansion tube Is attached.

The ultrasonic vibration device 150 is installed at the inlet through which the heat shrink tube 101 enters the expansion chamber 102, and thus has a cylindrical shape. In order to drive the ultrasonic vibrator 150, the ultrasonic vibrator 150 is connected to the AC power supply 151 having a predetermined electric power through a wire 152.

As the ultrasonic vibration device 150, a converter well known to those skilled in the art is used as a device capable of converting a predetermined electric signal into ultrasonic vibration. Representative apparatus that can be used as the ultrasonic vibration device 150 may be a piezoelectric element that can convert an electrical signal into a pressure.

Due to the ultrasonic vibration of the ultrasonic vibration device 150, the cooling water flowing between the porous expansion pipes 111 due to the capillary phenomenon may be introduced into the expansion pipe inner wall surface relatively quickly due to the ultrasonic vibration between the porous gaps.

In order to compare the quality of the heat shrink tube manufactured according to the present invention and the heat shrink tube manufactured according to the prior art shown in FIG. 1, the present inventors performed a predetermined experiment. The experiment was carried out by heating the surface temperature of the tube to 120 ° C ~ 170 ° C before entering the expansion chamber, making the produced feed flux within the range of 10m per minute to 20m per minute, and gradually increasing the internal pressure of the tube at 0.4 atm. Was performed.

At this time, the inner diameter of the tube was 1mm, the cooling water temperature was maintained at 0 ℃ ~ 20 ℃ and the vacuum pressure was maintained in the range of 600torr ~ 690torr. In addition, the flow volume of cooling water was kept in the range of 0.5 L / min-3 L / min.

The draw length deviation of the heat shrink tube produced according to the present invention under the above conditions was within 5mm of the maximum and minimum length deviation based on 100mm of the original tube.

On the other hand, in the case of the heat-shrink tube manufactured by the conventional expansion tube shown in FIG. 1, the maximum and maximum length deviations are 5 mm to 15 mm, and the deviation in the case of shrinking the heat shrink tube to be applied to the product is produced according to the present invention. It was relatively larger than the heat shrink tube.

The present invention is divided into regions for each section of the cooling water sprayed between the expansion tube holes in order to minimize the difference between the cooling water infiltrating near the region entering the expansion tube and the region discharged from the expansion tube along the direction of the heat shrink tube. Can be. Accordingly, there may be a difference in the cooling water spray in the divided section, it is possible to reduce the difference in the cooling water sprayed to the entire expansion pipe.

As a modification of the present invention, it may be formed as an expansion tube that can be detachably coupled expansion tube having a different hole diameter according to the diameter of the tube to be manufactured.

 The expansion tube for manufacturing a heat shrink tube having a porosity according to the present invention can increase the cooling effect of the heat shrink tube through the water film formed between the inner wall surface and the heat shrink tube between the porous tube.

In addition, the friction force in the direction opposite to the direction in which the heat shrink tube is manufactured by the lubrication of the water film formed as described above can be reduced.

Furthermore, the present invention can divide the expansion chamber into the inner wall surface to perform a vacuum operation mainly between the inner wall surface and the outer wall surface of the expansion chamber to coolant flow for cooling in the inner wall surface. As such, the present invention can reduce the influence of the pressure caused by the spraying of the cooling water and the change of the cooling water path due to the vacuum pressure by dividing the sections of cooling and expansion, thus spraying the cooling water relatively uniformly on the heat shrink tube and Pressure can be applied.

As a result, the cooling effect of the tube, the reduction of frictional force on the tube, and the action of uniform cooling water spray and uniform pressure can keep the shape of the tube relatively uniform, thus reducing the elongation of the heat shrink tube. The production speed of the heat shrink tube can be increased.

Although the present invention has been described in connection with the above-mentioned preferred embodiments, it is possible to make various modifications or variations without departing from the spirit and scope of the invention. Accordingly, the appended claims will cover such modifications and variations as fall within the spirit of the invention.

Claims (10)

In the expansion device for manufacturing a heat shrink tube for producing a heat shrink tube, An expansion chamber (102) connected to a cooling water pump (108a) for pressurizing and spraying cooling water and a vacuum pump (103) for inhaling gas to lower the pressure of the suctioned space; And And an expansion tube (111) disposed porous to allow the cooling water to flow into the expansion chamber (102) by capillary action. The apparatus for manufacturing a heat shrink tube having a porous expansion tube. According to claim 1, wherein the expansion chamber 102 is an expansion device for manufacturing a heat shrink tube having a porous expansion tube, characterized in that the inside is divided by the inner wall surface 121b in the longitudinal direction of the expansion chamber (102). . 3. The cooling water inlet 105b, which is connected to the cooling water pump 108 and sprays cooling water into the expansion chamber 102, has an inner wall 121b and the expansion pipe 111 of the expansion chamber. An expansion device for producing a heat shrinkable tube having a porous expansion tube, characterized in that installed on the space between. The cooling water inlet 105b is formed in plural and divides the space between the inner wall surface 121b of the expansion chamber and the expansion pipe 111 into a space in which the cooling water inlet 105b is formed. An expansion device for producing a heat shrinkable tube having a porous expansion tube. According to claim 2, In order to discharge the cooling water sprayed into the expansion tube 111 from the expansion tube 111 and to transfer the pressure of the vacuum pump 103, the inside of the expansion tube 111 and the expansion An expansion device for manufacturing a heat shrink tube having a porous expansion tube further comprises an expansion tube hole (113) connecting the space between the inner wall surface (121b) and the outer wall surface (121a) of the chamber (102). The apparatus of claim 5, wherein the expansion tube hole (113) is disposed at regular intervals in the longitudinal direction of the expansion tube (111). The apparatus of claim 1, further comprising a coolant filter (108b) between the coolant pump (108a) and the expansion chamber (102). The heat shrink tube having a porous expansion tube according to claim 1, further comprising an ultrasonic vibration device (150) attached to a manufacturing direction entrance of the heat shrink tube of the expansion tube (111) and converting electric power into ultrasonic vibration. Expansion device for manufacturing. 9. The expansion device for manufacturing a heat shrinkable tube having a porous expansion tube according to claim 8, wherein the ultrasonic vibration device (150) is a piezoelectric element. The expansion device for manufacturing a heat shrinkable tube having a porous expansion tube according to claim 1, wherein the temperature of the sprayed cooling water is in the range of 0 ° C to 20 ° C.

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