JPH0110177Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a die for granulating polymeric materials such as synthetic resins.

[Conventional technology]

As a granulation device for polymeric materials, a roughly disc-shaped granulation die having a large number of nozzle holes in the entire circumferential area within a certain range in the radial direction is attached to the tip of the extruder, and the front part of the die is cooled. There is a type in which a rotatable knife is provided in the water chamber, and the polymer material extruded from each nozzle hole of the die is cut into pellets by the knife, and the pellets are transported while being cooled with cooling water.

Conventionally, core jacket dies, heat channel dies, pipe dies, and the like have been known as granulation dies used in this type of apparatus, but generally all of these dies have been integrally formed as a whole. In other words, core jacket dies and heat channel dies have a large number of nozzle holes drilled in a predetermined area of the member that makes up the die, and a pipe die has a large number of pipes inserted into a predetermined area of the base material for welding or opening. However, in both cases, the die including the nozzle installation part and the mounting part for tightening bolts to the extruder is formed from an integral member (base material), and the nozzle hole is formed by attaching the die to the extruder. A heating jacket is fabricated and welded nearby. In addition, the surface of the nozzle part of the die is
Since the knife comes into contact with it during use, it has been treated to be wear-resistant.

[The problem that the idea aims to solve]

According to these structures, since the entire die is integral, the amount of overall distortion due to heat effects during welding and surface wear resistance treatment increases, and it is necessary to provide a large finishing allowance for subsequent finishing processing. Also, the size and shape of the jacket formed around the nozzle are limited. Furthermore, during normal operation, heat is lost to the entire die surface that is in contact with the cooling water on the nozzle exit side, resulting in a poor heating effect, and when resin pressure is applied, stress is also generated in the welded part of the jacket. As a result, problems such as cracks may occur and heating steam inside the jacket may leak. Furthermore, the nozzle hole must have corrosion resistance, and since plating is difficult, the entire nozzle hole must be integrally molded from stainless steel, which increases material costs. Furthermore, in the case of pipe dies, there are disadvantages such as distortion due to heat effects during processing, thermal distortion during use, distortion due to resin pressure, etc., which may create gaps between the pipe die and the base material, causing leakage of heated steam. It was hot.

As shown in Japanese Patent Publication No. 45-8797, a granulation die is formed by welding three parts: an inner part, a middle part, and an outer part, and a nozzle hole is arranged in the middle part. and a radially extending passageway is disposed in the intermediate portion for flowing the heating medium, and an inlet passageway and an outlet passageway communicating with the passageway are formed in the radial direction of the outer portion. A structure in which a portion corresponding to a heating jacket is formed in the passage is also known, but even with this structure, the following problems remain.

That is, in this structure, the passage corresponding to the heating jacket is provided across the intermediate part and the outer part, and the inner part also has the role of closing the tip of the passage, so that the passage corresponding to the heating jacket is In order to ensure sealing performance, it is necessary to weld the three parts mentioned above into one piece. However, when the three parts are welded in this way, the effect of absorbing strain between the parts cannot be obtained, so the granulation die is bent by the pressure applied during operation, and stress is applied to the welded part. Therefore, it is impossible to solve the problems of cracks caused by stress and leakage of the heating medium caused by the cracks.

This invention eliminates these drawbacks of conventional dies, reducing the amount of distortion caused by heat effects during welding and surface treatment, and also reduces stress due to pressure applied during operation, preventing steam leakage during operation. The purpose of the present invention is to provide a die for granulating a polymeric material, which can prevent the troubles caused by heating, can have a heating jacket in a relatively free shape and size, and can reduce material costs. It is something to do.

[Means to solve the problem]

In order to achieve the above-mentioned objectives, the present invention is generally disk-shaped, has a large number of nozzle holes in the entire circumferential area within a certain range in the radial direction, and has heating in the vicinity of the nozzle holes. A die for granulating a polymeric material, which has a heating jacket through which a medium flows and is bolted to the tip of an extruder, includes a nozzle member provided with a large number of nozzle holes, and a nozzle member surrounding the outer periphery of the nozzle member. a presser ring is formed separately from the presser ring, the heating jacket is provided on the nozzle member independently from the presser ring, and a bolt hole for attachment to the extruder is provided in the presser ring, and A nozzle member holding portion that engages with the nozzle member is provided on the inner peripheral portion of the holding ring.

[Effect]

According to the above configuration, the nozzle member and the presser ring are formed separately and engaged without being welded, thereby reducing distortion due to heat or pressure applied during operation. Further, since the heating jacket is formed independently on the nozzle member, the sealing performance of the heating jacket can be ensured without welding the nozzle member and the presser ring.

〔Example〕

Embodiments of the present invention will be described based on the drawings.

1 to 4 show an embodiment of the present invention,
The granulation die A of this embodiment is formed in advance into two parts: nozzle members 1 and 3 and a presser ring 2 surrounding the outside thereof, and the nozzle member is further divided into nozzle ring 1 and a presser plate 3. has been done.

The nozzle ring 1 is formed to a predetermined size so as to constitute a predetermined radially intermediate area of the die A, and has a large number of nozzle holes 11 penetrating the ring 1 in the front-rear direction (axial direction). It is perforated. Stepped pressed portions 12 and 13 are formed over the entire circumference on the outer and inner circumferential surfaces of the nozzle ring 1, respectively. In addition, heating jackets 14 and 15 through which a heating medium such as steam flows are provided at positions near the nozzle outlet on the outer circumference and inner circumference of the nozzle ring 1, respectively, independently of the presser ring 2 and the presser plate 3. , the nozzle ring 1 alone maintains airtightness. Each of the jackets 14 and 15 is constructed by, for example, machining a recess along the circumferential direction of an appropriate depth in a predetermined portion of the outer and inner peripheral surfaces of the nozzle ring 1, and providing plates 16 and 17 for closing each recess. It is formed by welding to the nozzle ring 1 and can be connected to a heating medium supply section (not shown) at an appropriate location. In this way, the heating jacket 1
4 and 15, the nozzle ring 1 is formed separately from the presser ring 2 and the presser plate 3 in advance, and the jackets 14 and 15 are formed on the outer and inner circumferences of the nozzle ring 1. Therefore, the machining and welding work for forming the jacket is easier than the conventional structure in which the entire parts corresponding to the three parts 1, 2, and 3 above are molded from a single material (base material) and a jacket is provided inside. become. Further, in this regard, there are fewer restrictions on processing and welding operations, so the sizes, shapes, etc. of the jackets 14 and 15 can be designed relatively freely.

On the other hand, the presser ring 2 is formed to a size that surrounds the outer periphery of the nozzle ring 1, and has bolt holes 21 arranged at a plurality of locations at appropriate intervals in the circumferential direction. The presser plate 3 is formed into a disk shape with a size corresponding to the internal space of the nozzle ring 1, and bolt holes 31 are provided at several appropriate locations. Further, on the inner circumferential surface of the presser ring 2 and the outer circumferential surface of the presser plate 3, there are stepped presser portions 2 corresponding to the pressurized portions 12 and 13, respectively.
2 and 32 are formed. This presser part 22, 2
3 and the pressed parts 12 and 13 are extruder B, which will be described later.
The nozzle rings 1 are provided in correspondence with each other so that they face each other when attached to the extruder B, and the nozzle rings 1 are pressed against the extruder B by the holding parts 22 and 32.

Note that each nozzle hole 11 through which the molten resin passes
...needs to have corrosion resistance, so usually
The nozzle ring 1 is made of stainless steel. In this case, material costs can be reduced by using stainless steel only for the nozzle ring 1 and using inexpensive materials such as general steel for the presser ring 2 and presser plate 3 that constitute the other parts of the die A. be able to. Further, the nozzle exit side surface 1a of the nozzle ring 1 is subjected to a surface wear-resistant treatment by thermally spraying a wear-resistant material. This wear-resistant treatment performed under high heat and the welding work for forming the jacket described above are performed on the nozzle ring 1, which is formed separately from the other parts of the die A, so it is similar to the conventional integrated structure. Compared to the case where the entire die is affected by heat during wear resistance treatment or welding, the amount of distortion due to heat is smaller, and the machining allowance for subsequent finishing processing can also be reduced.

When this die A is attached to the extruder B, the nozzle ring 1, the presser ring 2, and the presser plate 3 are engaged and matched inwardly and outwardly, as shown in FIGS. 2 and 3. In this state, it is brought into contact with the entire surface of extruder B. In this state, the presser ring 2 and the presser plate 3 are fastened to the die holding parts 52 and 53 provided around and inside the tip extrusion port 51 of the extruder B with bolts 4 .
By doing this, the presser ring and the presser plate 3 are fixed to the extruder B, and the nozzle ring 1 is held in a state pressed against the entire surface of the extruder B by the presser parts 22 and 32, and the die A
The whole thing is fixed. Further, a cooling water chamber 55 is provided in front of the die A, and a knife 56 that rotates along the nozzle exit side surface of the nozzle ring 1 is provided in the water chamber 55.

During use, the molten resin extruded from the extruder B through the nozzle holes 11 of the die A is cut into pellets by the knife 56, and is transported while being cooled and solidified by the cooling water in the water chamber 57. be done. In this case, the resin pressure applied to the nozzle ring 1 from the extruder B is received by the presser parts 22 and 32 and does not act on the welded parts of the jackets 14 and 15, resulting in damage to the welded parts and heating caused by this. The occurrence of leakage of steam is prevented.
In addition, at the boundary between the nozzle ring 1, the presser ring 2, and the presser plate 3, the thermal conductivity is lower than when the entire die is integrally molded, so the heat transfer to the presser ring 2 and the presser plate 3 is lower. Escape is suppressed and heating jackets 14, 15
Accordingly, the heating efficiency of the nozzle holes 11 is increased.

FIG. 5 shows another embodiment of the die A of the present invention. In this embodiment, as a structure for arranging a large number of nozzle holes 11' in the nozzle ring 1', nozzle forming pipes 18 are passed through the nozzle ring 1' and welded thereto. In addition, the pipe 18...
A jacket frame 1 having a substantially U-shaped cross section and having a penetrating portion of
By welding 6' to the nozzle ring 1', a heating jacket 14' is formed around the pipe 18 near the nozzle outlet. The structures of the presser ring 2, presser plate 3, etc. are the same as in the first embodiment. With this structure, the nozzle ring 1',
Since the retaining ring 2 and the retaining plate 3 are formed separately, processing and welding of the jacket 14' is facilitated, and since no resin pressure is applied to the welded part of the jacket during use, damage and damage are prevented. This embodiment has the same functions and effects as the first embodiment, such as preventing steam leakage and enhancing the heating effect.

FIG. 6 shows yet another embodiment of the invention. In this embodiment, heat insulating materials 19 are provided on the inner circumferential surface of the presser ring 2 and the outer circumferential surface of the presser plate 3 over the entire set. According to this structure, the jackets 14 and 15 are connected to the nozzle hole 11 due to the heat insulating effect of the heat insulating material 19 at the boundary between the nozzle ring 1, the presser ring 2, and the presser plate 3.
heating effect is further enhanced.

In the above embodiment, the granulating die A is divided into three parts, but in the case of a relatively small die, the nozzle ring 1 and the presser plate 3 are integrated to form a nozzle member, and this nozzle It is also possible to have a two-part structure consisting of the member and the presser ring 2. In other words, if the die is relatively small, even with such a two-part structure, it is possible to sufficiently reduce the amount of distortion due to heat effects during welding, etc., and the amount of distortion due to resin pressure during use, and the entire die is of one-piece construction, at least the outer jacket 14
Ease of processing and degree of design freedom are improved.

In addition to these embodiments, the specific structure of the die of the present invention may be modified in various ways without departing from the gist of the present invention.

[Effects of the invention] As explained above, the granulation die of the invention has the following advantages:
At least divided into a nozzle member having a large number of nozzle holes and a retainer ring surrounding the outer periphery of the nozzle member,
Since the nozzle member is fixed in a pressed state against the extruder by the nozzle member holding part provided on the holding ring, the amount of distortion due to heat effects during welding and surface wear resistance treatment can be reduced. Finishing allowances can be reduced, processing and welding of the heating jacket is easy, the size and shape of the jacket can be selected relatively freely, and the retainer ring is separate from the nozzle member. It has manufacturing advantages such as not requiring very high corrosion resistance and being able to be molded with inexpensive materials. Furthermore, in use, it can reduce distortion due to pressure applied during operation, prevent damage to the welded part of the heating jacket and leakage of the heating medium due to it, and enhance the heating effect of the nozzle hole by the heating jacket. be able to. In particular, since the heating jacket is independently provided on the nozzle member and the nozzle member and the retaining ring are engaged without welding, the sealing performance of the heating jacket is ensured while the pressure applied during operation is prevented. This has effects such as being able to reduce distortion and prevent the occurrence of cracks.

[Brief explanation of the drawing]

Fig. 1 is a half sectional view of an embodiment of the die of the present invention in an exploded state, Fig. 2 is a sectional view of the die installed in an extruder, and Fig. 3 is an enlarged sectional view of the same part.
FIG. 4 is a front view of a quarter of the same die, FIG. 5 is a cross-sectional view of a main part showing another embodiment, and FIG. 6 is a cross-sectional view of a main part showing still another embodiment. A... Granulation die, 1, 1'... Nozzle ring, 11, 11'... Nozzle hole, 2... Holder ring, 3... Holder plate, 14, 15, 14'...
... Heating jacket, 21, 31 ... Bolt hole,
22, 32... Nozzle ring holding part.

Claims (1)

[Scope of utility model registration request] The entire body is approximately disk-shaped, has a large number of nozzle holes in the entire circumferential area within a certain range in the radial direction, and has a heating jacket for circulating a heating medium in the vicinity of the nozzle holes. In a die for granulating a polymeric material that is bolted to the tip of a die, a nozzle member having a large number of nozzle holes and a presser ring surrounding the outer periphery of the nozzle member are formed separately, and the heating A jacket is provided on the nozzle member independently from the presser ring, while a bolt hole for mounting to the extruder is provided on the presser ring, and a bolt hole for attachment to the extruder is provided on the inner circumference of the presser ring to engage the nozzle member. A die for granulating a polymeric material, characterized in that it is provided with a nozzle member holding part.