JP5496288B2 - Die plate for underwater cut granulator - Google Patents

Description

  The present invention relates to a die plate of an underwater cut granulator used for producing, for example, resin pellets.

  As is well known, an underwater cut granulator used for producing resin pellets is provided on the downstream side of an extruder, and a die provided with a nozzle through which molten resin (molten processing material) is extruded. It has a plate and a cutter that cuts the resin extruded from the nozzle into particles while rotating. In addition, a circulation box that covers the die plate and the cutter is provided, and there is a water chamber filled with circulating cooling water inside the circulation box.

  In the die plate, a plurality of heat channels that pass through the heating medium are formed in order to keep the molten resin passing through the nozzle. The temperature of the molten resin passing through the nozzle is adjusted by supplying a heating medium such as high-temperature steam or oil to the channel of the heating channel. As described above, Patent Documents 1 to 2 disclose techniques for adjusting the temperature of a molten resin by supplying a heating medium to a heating channel.

  Patent Document 1 includes an annular passage through which a heating medium flows outside and inside a nozzle part ring, and a plurality of heating channels (heat channels) are formed between the outer annular passage and the inner annular passage. In the resin pellet manufacturing die provided with a large number of resin extrusion nozzles penetrating the nozzle part ring between the heat channels, the heat channel is extended from the small diameter passage side of the resin extrusion nozzle to the large diameter passage side by a predetermined length. This is a die for producing resin pellets.

  In Patent Document 2, a die for producing resin pellets in which a large number of nozzle holes are formed on the outer surface of the die extends in a direction intersecting with the resin flow channel in the vicinity of the outer surface of the die that leads to the nozzle. A die for producing resin pellets, which is provided with a plurality of rows of heat medium flow paths (heat channels) arranged along.

Japanese Patent Laid-Open No. 11-277528 JP 2001-179734 A

In the dice (die plate) in Patent Document 1 and Patent Document 2, the flow rate of the heating medium passing through the heat channel is not necessarily constant, and the nozzle close to the heat channel having a large flow rate is heated near the heat channel having a small flow rate. Nozzle had a small heating, and the heating variation was large depending on the position in the die plate.
Therefore, in the die plates of Patent Document 1 and Patent Document 2, there is a large variation in the heating conditions of the molten resin depending on the position of the nozzle, which affects the cutting of granulation and has a problem that the particle diameter of the product is not stable. It was. Further, in a nozzle that is not sufficiently heated, the molten resin may solidify in the nozzle and the nozzle hole may be blocked. In order to prevent these, it is conceivable to increase the flow rate of the heating medium or raise the temperature of the heating medium. In this case, however, the heat released from the die plate surface to the water chamber increases, There was a problem that efficiency deteriorated.

  In view of the above problems, the present invention easily stabilizes the flow rate of the heating medium flowing through the heat channel, thereby improving the heating efficiency of the heating medium flowing through the nozzle and the temperature of the processing material extruded from the nozzle. An object of the present invention is to provide a die plate for an underwater cut granulation apparatus in which the variation in granulation is small and the variation in granulation is small.

In order to achieve the above object, the present invention takes the following technical means.
In the die plate of the underwater cut granulator according to the present invention, a nozzle through which the molten processing material passes is formed, and a heating channel through which a heating medium for heating the processing material passing between the nozzles is formed. A circular die plate, wherein the heating channel includes an outer diameter channel formed on the outer diameter side, an inner diameter channel formed on the inner diameter side, and the outer diameter channel and the inner diameter channel. and a plurality of heat channels provided between and the nozzle in communication with the radial direction, before Kihi Tochane Le, it has flow stabilizing means for stabilizing the flow rate of the heating medium flowing through the heat channel is provided The flow rate stabilizing means is a throttle portion provided in each heat channel , and each throttle portion has the same cross-sectional area .

The narrowed portion is preferably formed so that a cross-sectional ratio between a cross-sectional area of the narrowed portion and a cross-sectional area of another portion of the heat channel is 10% or more and 50% or less.
The narrowed portion is preferably formed on the downstream side in which the heating medium flows in the heat channel.

  According to the present invention, the flow rate of the heating medium flowing through the heat channel can be easily stabilized.

It is side surface sectional drawing of an underwater cut granulation apparatus. It is an internal view of the die plate in a 1st reference form. It is sectional drawing (AA cross section of FIG. 2) of a heat channel. It is an internal view of the die plate in the 2nd reference form. It is sectional drawing of the heat channel of the die plate in this embodiment. It is sectional drawing of the conventional die plate. It is a figure which shows the flow volume of the heat channel in the comparative example 1. It is a figure which shows the flow volume of the heat channel in Example 1. FIG. FIG. 6 is a diagram showing the flow rate of the heat channel in Example 2. FIG. 10 is a diagram showing the flow rate of the heat channel in Example 3. It is a figure which shows the flow volume of the heat channel in Example 4. FIG.

Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.
[First Reference Form]
FIG. 1 is a side sectional view of an underwater cut granulator according to a first reference embodiment.
As shown in FIG. 1, the underwater cut granulator 1 is provided on the downstream side (resin discharge side) of the extrusion kneader 2 for kneading the molten resin, and is attached to the resin discharge side 2a of the extrusion kneader 2. A die plate 4 in which a large number of nozzles (die holes) 3 are formed, a cutter 5 for cutting out molten resin (melted processing material) extruded from the nozzle 3, and the cutter 5 is driven to rotate on the die plate 4. A driving means 6 and an annular box (case) 8 that forms a water chamber 7 together with the die plate 4 are provided.

In the case 8 (water chamber 7), a rotating shaft 9 of the driving means 6 is rotatably provided, and a disc-shaped cutter holder 10 is provided on the tip side (extruding kneader 2 side) of the rotating shaft 9, A cutter 5 is attached to the outer peripheral edge of the cutter holder 10.
In this underwater cut granulator 1, the molten resin is sent to a resin introduction hole 11 provided on the resin discharge side 2 a of the extrusion kneader 2, and the molten resin is passed through a plurality of nozzles 3 communicating with the resin introduction hole 11. Thus, the molten resin can be pushed out to the water chamber 7 side. On the other hand, by rotating the rotating shaft 9 of the driving means 6, the cutter 5 is rotated along the surface of the die plate 4 on the water chamber 7 side and is pushed out to the water chamber 7 side through the nozzle 3. The molten resin is cut into a predetermined size by the rotating cutter 5. The molten resin cut by the cutter 5 becomes pellets 12 in the water chamber 7, and the pellets 12 are directed toward the outlet 14 formed in the water chamber 7 by cooling water introduced from the inlet 13 formed in the water chamber 7. It is washed away and transported.

Hereinafter, the die plate 4 used in the underwater cut granulator 1 will be described in detail with reference to FIG. For convenience of explanation, the left and right sides of the sheet of FIG.
As shown in FIG. 2, the die plate 4 has a circular shape, and includes an outer body 15 constituting the outside, a die plate body 16 provided inside the outer body 15 and provided with the nozzle 3, and the die plate 4. And an inner body 17 provided inside the plate body 16.

The outer body 15, the die plate main body 16, and the inner body 17 form a heating flow path 18 through which a heating medium (for example, hot water) passes inside the die plate 4.
The heating flow path 18 communicates the outer diameter flow path 20 provided on the outer diameter side, the inner diameter flow path 21 provided on the inner diameter side, the outer diameter flow path 20 and the inner diameter flow path 21 in the radial direction, and And a plurality of heat channels 22 provided between the nozzles 3.

Specifically, the outer diameter flow path 20 is configured by separating the outer body 15 and the die plate body 16 in the radial direction. The in-diameter channel 21 is configured by separating the inner body 17 and the die plate body 16 in the radial direction. As shown in FIG. 3, the inner walls of the heat channel 22 have the same size and the same cross-sectional ratio.
As shown in FIG. 2, eight radially outer channels 20 are provided in the circumferential direction inside the die plate 4, and four radially inner channels 21 are provided in the circumferential direction. Each of the outer diameter flow paths 20 and the inner diameter flow paths 21 is symmetrical with respect to the center line C1 extending vertically, and is vertically symmetric with respect to the center line C2 extending horizontally. That is, the outer diameter flow path 20 and the inner diameter flow path 21 are provided in each area obtained by dividing the die plate 4 (outer body 15, die plate body 16, inner body 17) into four portions every 90 degrees.

Thus, the outer diameter flow path 20 and the inner diameter flow path 21 are provided in each symmetrical area obtained by dividing the die plate 4 into four parts.
Hereinafter, the first section (range of 0 to 90 degrees) will be described. The other parts are symmetrical and will not be described.
In the first section K, two outer diameter channels 20 (20a, 20b) are provided in the circumferential direction apart from each other, and a first partition 25 for partitioning both the outer diameter channels 20a, 20b is provided. Is provided. The first partition 25 prevents the heating medium in one outer diameter channel (first outer diameter channel) 20a from flowing to the other outer diameter channel (second outer diameter channel) 20b. In each section (area), a second partition 26 that partitions the outer diameter flow path 20 is provided in a portion adjacent to each other.

The first section K is provided with one inner diameter flow path 21, and this inner diameter flow path 21 extends from one side (90 degrees side) to the other side (0 degrees). Yes. In each section (area), a third partition 27 that partitions the inner diameter flow path 21 is provided in a portion adjacent to each other.
Within the first section K, a range of 90 to 45 degrees, i.e., a plurality of heat channels 22 are provided in the first area KA, and a range of 0 to 45 degrees, i.e., in the second area KB. A plurality of heat channels 22 are provided.

  The heat channel 22 provided in the first area KA allows the die plate body 16 to communicate with one first outer diameter flow path 20a and the inner diameter flow path 21 corresponding to the first outer diameter flow path 20a. It is configured by penetrating. Specifically, the outer diameters (one end) of the plurality of heat channels 22 provided in the first area KA communicate with one first outer diameter flow path 20a, and the inner diameters (the other end) of the plurality of heat channels 22 are It communicates with the in-diameter channel 21.

  The heat channel 22 provided in the second area KB passes through the die plate body 16 so as to communicate the second outer diameter flow path 20b and the inner diameter flow path 21 corresponding to the second outer diameter flow path 20b. It is comprised by. Specifically, the radially outer side (one end) of the plurality of heat channels 22 provided in the first area KB communicates with one second radially outer flow path 20b, and the radially inner side (the other end) of the plurality of heat channels 22 is It communicates with the in-diameter channel 21.

The heat channels 22 in the first area KA and the second area KB are located on both ends of the nozzle 3 and heat the treatment material passing through the nozzle 3 by passing a heating medium.
At least one of the outer diameter flow path 20, the inner diameter flow path 21, and the heat channel 22 is provided with a flow rate stabilizing unit that stabilizes the flow rate of the heating medium flowing through the heat channel 22.

In the flow rate stabilization means, the flow rate of the heating medium flowing through the plurality of heat channels 22 provided in the first area KA and the plurality of heat channels 22 provided in the second area KB varies greatly within each heat channel 22. The flow rate is made substantially the same without doing so.
The flow rate stabilizing means in the first reference embodiment is configured by appropriately arranging a supply port 30 for supplying a heating medium to the heating flow path 18 and a discharge port 31 for discharging the heating medium. The flow rate of the heating medium is stabilized by the positional relationship of the outlet 31.

  Specifically, the supply port 30 is provided in both the first outer diameter channel 20a and the second outer diameter channel 20b, and the discharge port 31 is the inner diameter channel 21 in which the supply port 30 is not provided. Is provided at a position that is substantially in the middle. That is, the supply port 30 for supplying the heating medium and the discharge port 31 for discharging the heating medium are respectively provided in the opposite flow paths with the heat channel 22 interposed therebetween. Yes.

Note that at least two supply ports 30 may be provided in the outer diameter flow path 20 for each section K, and at least one discharge port 31 may be provided on the inner diameter flow path 21 side for each section K. Good.
Thus, the supply port 30 is provided in each of the first outer diameter flow channel 20a and the second outer diameter flow channel 20b, and the discharge port 31 is provided in the inner diameter flow channel 21 on the side where the outer diameter flow channel 20 is not provided. Thus, the heating medium that has entered the first outer diameter flow path 20a passes through the heat channel 22 in the first area KA, enters the inner diameter flow path 21 in the first area KA, and toward the inner diameter flow path 21 toward the center. And then discharged from the discharge port 31.

The heating medium that has entered the second outer diameter flow path 20b passes through the heat channel 22 in the second area KB, enters the inner diameter flow path 21 in the second area KB, and moves toward the inner diameter flow path 21 toward the center. It flows and is discharged from the discharge port 31.
Accordingly, when the entire die plate 4 is viewed, the heating medium does not go back and forth inside and outside the diameter from the supply port 30 arranged outside to the discharge port 31 arranged inside (less return). It will flow smoothly from the outside diameter to the inside diameter. As a result, the flow rate of the heating medium in each heat channel 22 is stabilized.

[Second Reference Form]
FIG. 4 shows a modified example inside the die plate, which is a second reference embodiment.
Also in the second reference embodiment, since the outer diameter flow path 20 and the inner diameter flow path 21 are provided in each symmetrical area obtained by dividing the die plate 4 into four parts, the first section K (0 ˜90 degrees range) will be described. The other parts are symmetrical and will not be described.

One outer diameter flow path 20 is provided in the first section K. A second partition 26 is provided between the outer diameter flow paths 20 adjacent to each other. In the first section K, one in-diameter channel 21 is provided, and this in-diameter channel 21 extends from one side (90 degrees side) to the other side (0 degrees), as in the first reference embodiment. It is supposed to cover a range.
A plurality of heat channels 22 are provided between the outer diameter flow path 20 and the inner diameter flow path 21. That is, one outer diameter flow path 20 communicating with the plurality of heat channels 22 is provided, one inner diameter flow path 20 communicating with the plurality of heat channels 22 is provided, and the outer diameter of the heat channel 22 is the outer diameter flow path. 20 is in communication with the inner diameter flow path 21.

Also in this embodiment, a flow rate stabilizing means for stabilizing the flow rate of the heating medium flowing in the heat channel 22 is provided.
As in the first reference embodiment, the flow rate stabilizing means in the second reference embodiment is configured by the arrangement of the supply port 30 and the discharge port 31, and the heating medium depends on the positional relationship between the supply port 30 and the discharge port 31. The flow rate is stabilized. Specifically, the supply port 30 is provided at a position substantially in the middle of the outer diameter flow path 20, and the discharge port 31 is provided at a position substantially in the middle of the inner diameter flow path 21 where the supply port 30 is not provided. Yes. Note that at least one supply port 30 is provided on the outer diameter flow path 20 side for each section, and the discharge port 31 is also provided for the inner diameter flow path 21 for each section.
It is sufficient to provide at least one on the side.

By configuring the supply port 30 and the discharge port 31 in this manner, the heating medium that has entered the outer diameter flow path 20 passes through the heat channel 22 and enters the inner diameter flow path 21, and is discharged from the discharge port 31. The flow of the heating medium flowing in the heat channel 22 is stabilized without flowing back and forth (less return) and smoothly flowing from the outer diameter side to the inner diameter side.
As described above, according to the first reference form and the second reference form, the supply port 30 may be provided on either the outer diameter flow path 20 side or the inner diameter flow path 21 side, and the discharge port 31 What is necessary is just to be provided in the other of the outer diameter flow path 20 side or the inner diameter flow path 21 side in which the port 30 is not provided.

As described above, the flow rate stabilizing means for stabilizing the flow rate of the heating medium flowing in the heat channel 22 is configured by the positional relationship of the supply port 30 and the discharge port 31 with respect to the outer diameter flow path 20 and the inner diameter flow path 21. The overall flow rate deviation of the heating medium flowing in the heat channel 22 can be reduced by the flow rate stabilizing means.
[This embodiment]
FIG. 5 shows an embodiment of the flow rate stabilizing means.

  In the first reference form and the second reference form, the flow rate stabilizing means is configured by optimizing the positions of the supply port 30 and the discharge port 31. The flow stabilization means is configured by the shape of the heat channel 22 communicating with the flow channel 21 (the shape of the communication portion between the heat channel 22 and the outer diameter flow channel 20 or the communication portion between the heat channel 22 and the inner diameter flow channel 21). It is a thing.

In the first reference form and the second reference form, the cross-sectional ratio in the heat channel 22 is the same, but in this embodiment, the flow rate of the heating medium flowing in the heat channel 22 is changed by changing the cross-sectional area ratio. Stabilize. This will be described in detail below.
As shown in FIG. 5, each heat channel 22 is formed with a narrowed portion 33 having a smaller cross-sectional area than other portions. The cross-sectional areas of the throttle portions 33 of the heat channels 22 are the same. That is, the cross-sectional areas of all the throttle portions 33 provided in the heat channel 22 are the same.

  The restricting portion 33 is provided at the downstream end (the end of the heat channel 22) through which the heating medium flows, with reference to the direction in which the heating medium flows. When a heating medium is passed through the throttle unit 33, the flow is slightly disturbed downstream of the throttle unit 33. However, if the throttle unit 33 is provided at the downstream end of the heat channel 22, heating by the throttle unit 33 is performed. The disturbance of the medium flow occurs in the inner diameter flow path 21 and the outer diameter flow path 20 and does not occur in the heat channel 22. Thereby, the influence of the turbulent flow due to the provision of the throttle part 33 does not exist in the heat channel 22, and the flow rate of the heating medium can be stabilized compared to the throttle part 33 on the upstream side.

The cross-sectional ratio (S1 / S2) between the cross-sectional area of the narrowed portion 33 and the cross-sectional area of the other part of the heat channel 22 is 10% or more and 50% or less. When the cross-sectional ratio is less than 10%, the pressure loss becomes excessive when the heating medium is caused to flow through the heat channel 22, and when the cross-sectional ratio is larger than 50%, the effect of the throttle portion 33 tends to be reduced.
As described above, according to the present embodiment, the flow rate stabilizing means is configured by the throttle portions 33 having the same cross-sectional area formed in each heat channel 22, and the flow rate of the heating medium flowing through the heat channel 22 by the throttle portion 33 is reduced. Can be stabilized.

  More preferably, the throttle portion 33 is provided on the downstream side of the heat channel 22 and the cross-sectional ratio (S1 / S2) between the cross-sectional area of the throttle portion 33 and the cross-sectional area of other portions of the heat channel 22 is 10% to 50%. It is good to do.

Table 1 summarizes the experimental results of an example using the die plate of the present invention and a comparative example using a conventional die plate different from the present invention.
7 to 11 summarize flow rate changes in the heat channels 22 in the examples and comparative examples. In the figure, the flow number indicates the order of the heat channels 22. For example, the flow number 10 indicates the tenth heat channel 22. 7 to 11
The flow velocity in FIG. 4 describes the difference after measuring the flow rate at both ends of the heat channel 22. Further, in the same figure, it is shown that when the fluctuation of the flow velocity is small with reference to the flow velocity of 0 m / s, the return is small, and when the fluctuation is large, the return is large. In FIG. 7 to FIG. 11, the symbol [◯] indicates the first result, and the symbol [□] indicates the second result.

“Example 1” in Table 1 is an example of the first reference form, and “Example 2” is an example of the second reference form described above. Examples of the present embodiment are “Example 3” and “Example 4”.
A flow path model A shown in Table 1 shows the die plate 4 in which the heat channel 22 is not provided with the throttle portion 33, and shows that the ratio of the cross-sectional area of the heat channel 22 is the same. The flow channel model B shows the die plate 4 in which the narrowed portion 33 is provided in the heat channel 22, and the ratio of the cross-sectional area of the heat channel 22 is in the range of 10% to 50%.

In Comparative Example 1, a die plate 4D having the same positions as the conventional ones of the supply port 30 and the discharge port 31 was used. That is, in Comparative Example 1, as shown in FIG. 5, one supply port 30 is provided on the radially outer side and one discharge port 31 is provided on the radially outer side for each section (range of 0 to 90 degrees). The die plate 4D was used (Table 1, column “Outside 1” for supply position and number, “Outside 1” for discharge position and number).
In Example 1, a die plate 4A as shown in FIG. 2 in which two supply ports 30 are provided on the radially outer side and one discharge port 31 is provided on the radially inner side for each section (range of 0 to 90 degrees). (Table 1, column “outside 2” of supply position and number, “inside 1” of discharge position and number “).

In Example 2, a die plate 4B as shown in FIG. 3 in which one supply port 30 is provided on the outer diameter side and one discharge port 31 is provided on the inner diameter side for each section (range of 0 to 90 degrees). (Table 1, column “Outside 1” for supply position and number, “Inside 1” for discharge position and number “)”.
In Example 3, the positions of the supply port 30 and the discharge port 31 are the same as those shown in FIG. 2, and a die plate 4C having a constricted portion 33 in the heat channel 22 is used (Table 1, supply position and number). Column "Outside 2", discharge position and number column "Inside 1").

In Example 4, the positions of the supply port 30 and the discharge port 31 are the same as those shown in FIG. 3, and the die plate 4C provided with the constricted portion 33 in the heat channel 22 is used (Table 1, supply position and number). Column "Outside 2", discharge position and number column "Inside 1").
In Comparative Example 1 and Examples 1 to 4, the heating medium (warm water) is supplied from the supply port 30 and the heating medium is discharged from the discharge port 31 for each die plate 4. The flow rate of the medium was measured. The correlation between the flow rate of the heating medium in the heat channel 22 and the surface temperature of the die plate 4 has been confirmed in the past by measuring the surface temperature. The surface temperature of the die plate 4 is high near the region where the heat channel 22 where the flow rate of the heating medium is large, and the surface temperature is low near the region where the heat channel 22 where the flow rate of the heating medium is small. And the uniformity of the surface temperature of the die plate 4 (the degree of heating of the processing material in the nozzle 3) has a correlation.

As described above, if the flow rate distribution of the heat channels 22 is made uniform (the flow rate of the heating medium flowing in each heat channel 22 is stabilized), the surface temperature of the die plate 4 is made uniform (the processing material in the nozzle 3 is treated). In contrast, the temperature of the processing material extruded from the nozzle 3 is constant and the granulation variation is small.
Therefore, as shown in Comparative Example 1 and Examples 1 to 4, the degree of variation in the flow rate of the heating medium in each heat channel 22 was evaluated.

  Specifically, in the evaluation of Comparative Example 1 and Examples 1 to 4, the standard deviation indicating the variation in the flow rate in the plurality of heat channels 22 is obtained by Equation (1), and the standard deviation of the flow rate is 0.5. If it was above, it was set as the defect (Table 1, the uniformity of flow volume, "x"). When the standard deviation of the flow rate was less than 0.5, it was considered good, and among the good ones with small standard deviation, evaluation was performed in stages (Table 1, uniformity of flow rate, “Δ”, “○ "," ◎ ").

In Comparative Example 1, since the flow rate stabilization means as in the present invention is not provided, as shown in FIG. 7, from the IN side (supply port 30 side) to the OUT side (discharge port 31 side), that is, the flow rate. From No. 1 to No. 20, the flow rate variation of the heating medium (flow rate deviation of each heat channel, flow rate deviation) is large as a whole (Table 1, uniformity of flow rate, “×”).
On the other hand, in Example 1, compared with Comparative Example 1, two supply ports 30 are provided in the outer diameter flow path 20 and one discharge port 31 is provided so that the heating medium does not go back and forth inside the diameter. Since it is provided in the inner diameter flow path 21, as shown in FIG. 8, the flow rate deviation is large in the vicinity of the IN side and the OUT side, but the flow rate deviation is small in the middle part (flow rate numbers 4 to 17). (Table 1, uniformity of flow rate, “Δ”).

  Further, in the second embodiment, one supply port 30 is provided in the outer diameter flow path 20 and one discharge port 31 is provided in the inner diameter flow path 21 so that the heating medium does not go back and forth inside and outside the diameter. Therefore, as shown in FIG. 9, the flow rate deviation is slightly large near the middle (flow rate number around 10), but the flow rate deviation is small as a whole (Table 1, uniformity of flow rate). , “○”).

Further, in the third embodiment, since the two supply ports 30 are provided in the outer diameter flow path 20 and the one discharge port 31 is provided in the inner diameter flow path 21, and further, the throttle portion 33 is provided in the heat channel 22, As shown in FIG. 10, the flow rate deviation was small as a whole (Table 1, uniformity of flow rate, “◎”).
In the fourth embodiment, since one supply port 30 is provided in the outer diameter flow path 20 and one discharge port 31 is provided in the inner diameter flow path 21, and furthermore, the throttle portion 33 is provided in the heat channel 22, FIG. As shown, the flow rate deviation was small as a whole (Table 1, uniformity of flow rate, “◎”).

According to the third and fourth embodiments, the positions of the supply port 30 and the discharge port 31 are adjusted so that the flow of the heating medium in the heat channel 22 is improved, and the throttle portion 33 is provided in the heat channel 22. Thus, the deviation of the flow rate of the heating medium flowing in the heat channel 22 could be eliminated most.
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  In the above embodiment, the supply port 30 is provided in the outer diameter flow channel 20 and the discharge port 31 is provided in the inner diameter flow channel 21. However, the present invention is not limited thereto, and the supply port 30 is provided in the inner diameter flow channel 21. The supply port 30 and the discharge port 31 may be reversely provided as the discharge port 31 provided in the outer diameter flow path 20.

DESCRIPTION OF SYMBOLS 1 Underwater cut granulator 18 Heating flow path 20 Outer diameter flow path 21 Inner diameter flow path 22 Heat channel 30 Supply port 31 Discharge port

Claims (3)

A circular die plate in which a nozzle through which a molten processing material passes is formed and a heating flow path through which a heating medium that heats the processing material passing between the nozzles passes is formed,
The heating channel includes an outer diameter channel formed on the outer diameter side, an inner diameter channel formed on the inner diameter side, the outer diameter channel and the inner diameter channel in the radial direction, and between the nozzles. A plurality of heat channels provided in the
Before Kihi Tochane Le, the flow rate stabilizing means for stabilizing the flow rate of the heating medium flowing through the heat channel is provided,
The flow rate stabilizing means is a throttle part provided in each heat channel , and each throttle part has the same cross-sectional area.   The said throttle part is formed so that the cross-sectional ratio of the cross-sectional area of the said throttle part and the cross-sectional area of the other part of the said heat channel may be 10% or more and 50% or less. The die plate of the underwater cut granulator described. The die plate of the underwater cut granulator according to claim 1, wherein the narrowed portion is formed on a downstream side in which the heating medium flows in the heat channel.