CN114368127A

CN114368127A - Ultrahigh molecular weight polyethylene extrusion molding die

Info

Publication number: CN114368127A
Application number: CN202210036493.9A
Authority: CN
Inventors: 邓梓燚; 曾艳祥; 覃健召; 陈立彬
Original assignee: Siiico Technology Co ltd
Current assignee: Siiico Technology Co ltd
Priority date: 2022-01-13
Filing date: 2022-01-13
Publication date: 2022-04-19

Abstract

The invention discloses an ultrahigh molecular weight polyethylene extrusion molding die which is provided with an X direction, a Y direction and a Z direction which are mutually orthogonal; the extrusion molding die includes: the die comprises a die main body, a die core and a die core, wherein two ends of the die main body in the X direction are respectively arranged as an extruder connecting end and a product end; the heating structure is relatively fixed with the die main body, the number of the heating structures is multiple, the heating structures are arranged along the X direction, and the heating temperatures of the heating structures are decreased progressively. Through the gradual reduction of the temperature of the materials, the phenomenon that the material cooling speed is too high due to the adoption of liquid cooling and other modes in the subsequent cooling step can be avoided, so that the undesirable conditions that the product is cracked in the shaping stage are avoided, and the quality of the product can be ensured.

Description

Ultrahigh molecular weight polyethylene extrusion molding die

Technical Field

The invention relates to the technical field of extrusion dies, in particular to an ultrahigh molecular weight polyethylene extrusion die.

Background

The ultrahigh molecular weight polyethylene is thermoplastic engineering plastic with molecular weight higher than 150 ten thousand, has molecular chain length 10-20 times that of high density polyethylene, and has toughness, wear resistance and stress cracking resistance, so that the polyethylene has lubricating property, chemical resistance and excellent electric performance.

The ultrahigh molecular weight polyethylene has excellent performance, is one of the best currently known ultrahigh molecular weight polyethylene simply in terms of service performance, and the excellent performance of the ultrahigh molecular weight polyethylene is derived from the extremely high molecular weight of the polyethylene, so that the judgment on the success or failure of modification of the ultrahigh molecular weight polyethylene depends on the degree of molecular weight retention of a product and impact toughness at low temperature to a great extent, the ultrahigh molecular weight polyethylene has extremely high melt viscosity and extremely poor flowability, the ultrahigh molecular weight polyethylene is difficult to process by using traditional plastic forming equipment and processes, and the application of the ultrahigh molecular weight polyethylene at home and abroad is concentrated on pressed products due to the processing difficulty.

Even if the existing extrusion die for ultra-high molecular weight polyethylene exists in the prior art, the existing extrusion die specially used for ultra-high molecular weight polyethylene usually needs a relatively long runner so that the ultra-high molecular weight polyethylene product can be well molded, and a heating device matched with the runner is arranged on the die so that a certain temperature is kept in the flowing process of the material to facilitate molding. However, the number of the heating devices in the prior art is usually only one, or a plurality of heating devices with the same heating temperature are adopted to heat the material in the flow channel, after the material is completely formed into a required shape, in order to ensure the quality of the product and avoid the product from being bent greatly after being extruded, a space for cooling the material needs to be reserved in the die, the material needs to be cooled gradually in the cooling space, and the material needs to be cooled to a certain temperature and then can be sent out of the die.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: an ultra-high molecular weight polyethylene extrusion die is provided to solve one or more technical problems in the prior art, and at least provide a useful choice or creation.

The solution of the invention for solving the technical problem is as follows:

an ultra-high molecular weight polyethylene extrusion molding die is provided with an X direction, a Y direction and a Z direction which are mutually orthogonal; the extrusion molding die includes: the die comprises a die main body, a die core and a die core, wherein two ends of the die main body in the X direction are respectively arranged as an extruder connecting end and a product end; the heating structure is relatively fixed with the die main body, the number of the heating structures is multiple, the heating structures are arranged along the X direction, and the heating temperatures of the heating structures are decreased progressively.

Through the technical scheme, because during the extrusion molding, the cross section near the one end of the extruder changes greatly, correspondingly, be equipped with the higher heating structure of heating temperature, be enough to change to corresponding cross sectional shape in a certain distance in order to guarantee the mobility of material, along with the material is constantly marchd, the part that the cross section needs to change reduces gradually, can suitably reduce the temperature in the part that is close to the extruder in comparison and guarantee that the material can take place deformation smoothly, can realize the temperature reduces gradually in the material forming process through setting up the degressive heating structure of temperature, can reduce the required cooling space's of product design stage requirement, in order to avoid in the past the material forming process temperature keep invariable, the phenomenon that the design stage needs longer cooling space to supply material cooling design, make the length of mould reduce, reduce the manufacturing cost of mould. And the temperature of the materials is gradually reduced, so that the phenomenon that the temperature reduction speed of the materials is too high due to the adoption of liquid cooling and other modes in the subsequent cooling step can be avoided, the undesirable conditions that the products are cracked in the shaping stage are avoided, and the quality of the products can be ensured.

As a further improvement of the above technical scheme, the product end is provided with an installation groove, the mold core is installed in the installation groove, and the mold core is detachably connected with the mold main body; limit structure is installed to the product end, limit structure with the mould main part is fixed relatively, limit structure is used for right the mold core carries on spacingly, in order to avoid the mold core deviates from the mounting groove.

Through above-mentioned technical scheme, the staff can directly change the mold core to make the extruder can produce different products, the mold core change finish only need with limit structure to the mold core carry on spacingly can, can effectively improve mill's production efficiency.

As a further improvement of the technical scheme, a cooling water channel is arranged in the limiting structure.

Through above-mentioned technical scheme, the heat that the cooling water course enabled the mold core can conduct to other places fast to cool off the product.

As a further improvement of the above technical solution, the mold core is provided with a flow channel structure, the flow channel structure includes a transition flow channel, a shaping flow channel and a plurality of gradually-reduced flow channels, the transition flow channel, the shaping flow channel and the gradually-reduced flow channels all extend along the X direction, the transition flow channel is communicated with the gradually-reduced flow channels, the plurality of gradually-reduced flow channels are sequentially arranged along the X direction, and the plurality of gradually-reduced flow channels perform a plurality of times of shaping on the material to gradually form the material into a desired shape; the shaping flow channel is arranged on one side, far away from the transition flow channel, of the reducing flow channel, the shaping flow channel is communicated with the reducing flow channel, and the reducing flow channel gradually reduces from the transition flow channel to the cross section of the shaping flow channel.

Through the technical scheme, the high-temperature melting ultrahigh molecular weight polyethylene extruded from the extruder sequentially flows through the transition flow channel, the reducing flow channel and the shaping flow channel, the transition flow channel provides buffering and stacking space for the ultrahigh molecular weight polyethylene, the phenomenon that the material cannot be filled due to the fact that the difference between the area of a discharge port of the extruder and the cross section area of a final product is too large is avoided, and the defects of the product can be reduced; the cross section of the tapered runner is gradually reduced, so that different cross sections are formed in each shaping stage of the material, the material is shaped for different shapes for many times, the gradually reduced cross section can be favorable for shaping the ultrahigh molecular weight polyethylene with poor flowability and high viscosity, and the phenomenon that the middle part of a product is broken or the quality of the product is reduced due to uneven material caused by sudden change of the cross section of a cavity is avoided. The molding runner is used for maintaining the shape of the material, so that the shape of the product is maintained while the temperature of the material is gradually reduced, the product is prevented from being bent under the action of gravity after being extruded, and the quality of the product is ensured. The flow channel structure is matched with a product with a complex shape, so that the ultra-high molecular weight polyethylene can be produced by an extrusion molding process.

As a further improvement of the above technical solution, the mold core includes a glue feeding portion and a molding portion, the glue feeding portion and the molding portion are arranged along a direction from a glue feeding end to an extrusion end, and the glue feeding portion and the molding portion are separably connected; the transition runner set up in advance gluey part, the design runner with the convergent runner all set up in the shaping part.

Through above-mentioned technical scheme, advance gluey part and shaping part and set up to two parts of separable connection, overhaul the in-process of a certain part at the staff, can directly change the part that corresponds of new when making a certain part damage to improve mould maintenance efficiency, and can avoid overhauing and delay factory production.

As a further improvement of the above technical solution, the mold core includes a main core body and an insert body, the main core body is provided with an insert groove, and the insert body is mounted in the insert groove.

According to the technical scheme, the mold core is in the form of the main core body plus the insert body, so that on one hand, a new insert body can be replaced when the insert body is damaged, and the maintenance cost of the mold is reduced; on the other hand, the device can be used for the shape of a cavity which cannot be formed by conventional processing so as to adapt to a product with a more complex shape.

As a further improvement of the technical scheme, the notch of the insert groove is provided with a first guide chamfer.

Through the technical scheme, when the insert body is installed, the first guide chamfer can guide the insert body, so that the insert body is easier to install.

As a further improvement of the above technical scheme, the insert body is provided with a second guide chamfer.

Through the technical scheme, when the insert body is installed, the second guide chamfer can guide the insert body, so that the insert body is easier to install.

As a further improvement of the above technical solution, the heating structure includes two heating members, the heating member is provided with a first abutting portion, a second abutting portion and a connecting portion, the first abutting portion and the second abutting portion are vertically arranged, the first abutting portion and the second abutting portion respectively abut against two adjacent side walls of the mold main body, the number of the connecting portion is set to be more than two, two the connecting portion of the heating member can be detachably connected.

Through above-mentioned technical scheme, two heating members can be dismantled and connect, damage or unable normal during operation when heating structure, can directly pull down two heating members, the heating structure of renewal afterwards can to but design into the not equidimension mould main part of structure adaptation of two heating members with heating structure, can strengthen heating structure's practicality.

The invention has the beneficial effects that: the length of the die can be reduced, and the production cost of the die is reduced. Meanwhile, the occurrence of undesirable conditions such as cracks and the like of the product in the shaping stage can be avoided, and the quality of the product can be ensured.

The invention is used in the technical field of extrusion dies.

Drawings

In order to more clearly illustrate the technical solution in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below. It is clear that the described figures are only some embodiments of the invention, not all embodiments, and that a person skilled in the art can also derive other designs and figures from them without inventive effort.

FIG. 1 is a schematic diagram of the overall structure of an embodiment of the present invention;

FIG. 2 is a schematic view of the overall structure of the mold core according to the embodiment of the present invention;

FIG. 3 is a schematic view of a portion of a mold core according to an embodiment of the invention;

FIG. 4 is an enlarged partial schematic view of portion A of FIG. 3;

FIG. 5 is a partial schematic view of another angle of the mold core of an embodiment of the present invention.

In the figure, 110, a transition flow channel; 120. shaping the flow channel; 130. a tapered flow channel; 230. a glue inlet part; 240. a molding portion; 250. a main core body; 251. an insert pocket; 252. a first guide chamfer; 260. an insert body; 261. a second guide chamfer; 300. a mold body; 310. a limiting structure; 400. a heating structure; 410. a first abutting portion; 420. a second abutting portion; 430. a connecting portion.

Detailed Description

The conception, the specific structure, and the technical effects produced by the present invention will be clearly and completely described below in conjunction with the embodiments and the accompanying drawings to fully understand the objects, the features, and the effects of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and those skilled in the art can obtain other embodiments without inventive effort based on the embodiments of the present invention, and all embodiments are within the protection scope of the present invention. In addition, all the coupling/connection relationships mentioned herein do not mean that the components are directly connected, but mean that a better coupling structure can be formed by adding or reducing coupling accessories according to specific implementation conditions. All technical characteristics in the invention can be interactively combined on the premise of not conflicting with each other.

Referring to fig. 1 to 5, an ultra-high molecular weight polyethylene extrusion mold is provided with an X direction, a Y direction, and a Z direction, which are orthogonal to each other. The extrusion die includes a die body 300 and a heating structure 400.

Both ends of the die main body 300 in the X direction are respectively set as an extruder connection end and a product end. The mold main body 300 is provided with a mounting groove in which a mold core is inserted and installed. The product end of mould main part 300 passes through screw fixedly connected with limit structure 310, and limit structure 310 is used for spacing to the mold core, makes the mold core keep being located the mounting groove, is equipped with the cooling water course in the limit structure 310, and the cooling water course is used for circulating coolant, makes the heat of mold core can conduct to other places fast to the product end to the mold core cools off.

The number of the heating structures 400 is set to three (in other embodiments, the number of the heating structures 400 may be set to two or more than four), the three heating structures 400 are arranged along the X direction, and the heating temperature of the heating structures 400 decreases from the connecting end of the extruder to the product end. The heating structure 400 includes two heating members, the heating member is provided with a first abutting portion 410, a second abutting portion 420 and two connecting portions 430, the number of the connecting portions 430 is two, the two connecting portions 430 are respectively located at two ends of the heating member, and the two connecting portions 430 are respectively fixedly connected with the first abutting portion 410 and the second abutting portion 420. The first abutting portion 410 and the second abutting portion 420 abut against two adjacent side walls of the mold body 300, respectively. Connecting portion 430 of two heating members is connected through the screw, and the mode of connection can be dismantled in two heating member adoption, can directly dismantle heating structure 400 and the heating structure 400 of renewal when heating structure 400 can't normally work can, make things convenient for the staff to overhaul to but not equidimension mould main part 300 of structure adaptation through designing heating structure 400 into two heating members can strengthen heating structure 400's practicality.

The mold core comprises a glue inlet part 230 and a molding part 240, wherein the glue inlet part 230 and the molding part 240 are arranged along the X direction, and the glue inlet part 230 and the molding part 240 are detachably connected. One end of the forming part, which is far away from the glue inlet part, is provided with a step-shaped structure, and the limiting structure is matched with the step-shaped structure to limit the mold core.

The mold core includes a main core body 250 and an insert body 260. The main core 250 is formed by combining the glue inlet portion 230 and the molding portion 240, the main core 250 is provided with an insert groove 251, the insert groove 251 is provided in the molding portion 240, a notch of the insert groove 251 is provided with a first guide chamfer 252, and the insert body 260 is provided with a second guide chamfer 261. When the insert body 260 is mounted, the first guide chamfer 252 and the second guide chamfer 261 can guide each other, so that the insert body 260 can be more easily inserted into the insert groove 251. The insert body 260 is mounted in the insert groove 251.

The mold core is provided with a flow channel structure, which includes a transition flow channel 110, a shaping flow channel 120 and a tapered flow channel 130 (in this embodiment, the number of the tapered flow channels 130 is set to be one, and in other embodiments, the number of the tapered flow channels 130 can also be set to be multiple, so that the material gradually forms the shape required by the product). The transition flow passage 110, the tapered flow passage 130 and the shaping flow passage 120 are sequentially arranged and communicated in the X direction. The tapered flow channel 130 gradually decreases in cross-section from the transition flow channel 110 to the shaped flow channel 120. The shaped flow channel 120 extends toward the tapered flow channel 130, and the cross-section of the shaped flow channel 120 is gradually reduced while maintaining the shape of the final product. And the transition runner 110 is disposed at the glue inlet portion 230, and the shaping runner 120 and the tapered runner 130 are disposed at the forming portion 240.

While the preferred embodiments of the present invention have been illustrated and described, it will be understood by those skilled in the art that the present invention is not limited to the details of the embodiments shown and described, but is capable of numerous equivalents and substitutions without departing from the spirit of the invention as set forth in the claims appended hereto.

Claims

1. The utility model provides an ultrahigh molecular weight polyethylene extrusion molding mould which characterized in that: an X direction, a Y direction and a Z direction which are mutually orthogonal are arranged; the extrusion molding die includes:

the die comprises a die main body (300), wherein two ends of the die main body (300) in the X direction are respectively provided with an extruder connecting end and a product end, and the die main body (300) is provided with a die core;

the heating structures (400) are fixed relative to the die main body (300), a plurality of heating structures (400) are arranged, the heating structures (400) are arranged along the X direction, and the heating temperatures of the heating structures (400) are gradually decreased.

2. An ultra high molecular weight polyethylene extrusion die as recited in claim 1, wherein: the product end is provided with an installation groove, the mold core is installed in the installation groove, and the mold core is detachably connected with the mold main body (300); limit structure (310) are installed to the product end, limit structure (310) with mould main part (300) relatively fixed, limit structure (310) are used for right the mold core carries on spacingly, in order to avoid the mold core deviates from the mounting groove.

3. An ultra high molecular weight polyethylene extrusion die as recited in claim 2, wherein: a cooling water channel is arranged in the limiting structure (310).

4. An ultra high molecular weight polyethylene extrusion die as recited in claim 1, wherein: the mold core is provided with a flow channel structure, the flow channel structure comprises a transition flow channel (110), a shaping flow channel (120) and a plurality of gradually-reduced flow channels (130), the transition flow channel (110), the shaping flow channel (120) and the gradually-reduced flow channels (130) all extend along the X direction, the transition flow channel (110) is communicated with the gradually-reduced flow channels (130), the plurality of gradually-reduced flow channels (130) are sequentially arranged along the X direction, and the plurality of gradually-reduced flow channels (130) carry out a plurality of times of shaping on materials to enable the materials to gradually form required shapes; the shaping flow channel (120) is arranged on one side, far away from the transition flow channel (110), of the reducing flow channel (130), the shaping flow channel (120) is communicated with the reducing flow channel (130), and the cross section of the reducing flow channel (130) is gradually reduced from the transition flow channel (110) to the shaping flow channel (120).

5. An ultra high molecular weight polyethylene extrusion die as recited in claim 4, wherein: the mold core comprises a glue inlet part (230) and a forming part (240), the glue inlet part (230) and the forming part (240) are arranged along the direction from the connecting end of the extruder to the product end, and the glue inlet part (230) and the forming part (240) are detachably connected; the transition flow channel (110) is arranged on the glue inlet part (230), and the shaping flow channel (120) and the tapered flow channel (130) are arranged on the forming part (240).

6. An ultra high molecular weight polyethylene extrusion die as recited in claim 1, wherein: the mold core comprises a main core body (250) and an insert body (260), wherein the main core body (250) is provided with an insert groove (251), and the insert body (260) is installed in the insert groove (251).

7. An ultra high molecular weight polyethylene extrusion die as recited in claim 6, wherein: the notch of the insert groove (251) is provided with a first guide chamfer (252).

8. An ultra high molecular weight polyethylene extrusion die as recited in claim 6, wherein: the insert body (260) is provided with a second guide chamfer (261).

9. An ultra high molecular weight polyethylene extrusion die as recited in claim 1, wherein: the heating structure (400) comprises two heating pieces, wherein each heating piece is provided with a first abutting part (410), a second abutting part (420) and a connecting part (430), the first abutting parts (410) and the second abutting parts (420) are vertically arranged, the first abutting parts (410) and the second abutting parts (420) are respectively abutted against two adjacent side walls of the die main body (300), the number of the connecting parts (430) is more than two, and the connecting parts (430) of the heating pieces are detachably connected.