阅读说明：本技术 Pok专用挤出螺杆 (Special extrusion screw for POK (polyester pre-oriented Ketone) ) 是由 朱子更 于 2020-04-27 设计创作，主要内容包括：本发明涉及POK专用挤出螺杆,进料段包括螺距相等的第一螺纹,挤料段包括第二螺纹,第二螺纹第一段螺距与第一螺纹相等,第二螺纹位于第一段螺距后的螺距设为相等,第二螺纹位于第一段螺距后端大于第一段螺距,保持溶料段第三螺纹小于第二螺纹第一段螺距,回压压力段第四螺纹大于第二螺纹后端螺距,第一、二、三、四螺纹外圆直径设为相等,第一螺纹的底径自前往后逐渐增加,第二螺纹的前端底径大于第一螺纹底径,第二螺纹前端至中端、逐渐增加,第二螺纹中端至第三螺纹和第四螺纹底径设为相等,第一、二、三螺纹螺棱宽度设为相等,第一螺纹螺棱宽度小于第四螺纹螺棱宽度。本发明的优点：保持进料畅通,不烧黑POK料,不卡死螺杆。(The invention relates to a special extrusion screw for POK (polyester pre-oriented polypropylene), wherein a feeding section comprises first threads with the same thread pitch, an extruding section comprises second threads, the thread pitch of the first section of the second threads is equal to that of the first threads, the thread pitch of the second threads after the thread pitch of the first section is equal, the thread pitch of the second threads after the thread pitch of the first section is larger than that of the first section, the third threads of a material dissolving section are kept smaller than the thread pitch of the first section of the second threads, the fourth threads of a back pressure section are larger than the thread pitch of the rear end of the second threads, the diameters of the outer circles of the first, second, third and fourth threads are equal, the bottom diameter of the first threads is gradually increased from front to back, the bottom diameter of the front end of the second threads is larger than that of the first, gradually increasing, the bottom diameters of the third thread and the fourth thread from the middle end of the second thread to the middle end of the second thread are equal, the widths of the first thread edge, the second thread edge and the third thread edge are equal, and the width of the first thread edge is smaller than that of the fourth thread edge. The invention has the advantages that: keeping smooth feeding, not burning black POK materials and not blocking the screw.)

The special extrusion screw for the POK comprises a screw head and a screw body, and is characterized in that: the screw body comprises a feeding section, an extruding section, a material dissolving section and a back pressure section from front to back in sequence, the feeding section comprises a first thread, the thread pitch of the first thread is equal, the extruding section comprises a second thread, the first thread pitch of the second thread is equal to the thread pitch of the first thread, the thread pitch of the second thread at the rear end of the first thread pitch is equal to the thread pitch of the first section pitch, the thread pitch of the second thread at the rear end of the first section pitch is larger than the first section pitch, the material dissolving section comprises a third thread, the third thread pitch is equal to the thread pitch, the third thread pitch is smaller than the first thread pitch of the second thread, the back pressure section comprises a fourth thread, the thread pitch of the fourth thread is equal to the thread pitch of the second thread at the rear end of the first section pitch, the excircle diameters of the first thread, the second thread, the third thread and the fourth thread are equal to each other, the base diameter of the first thread is gradually increased from front to back, the base diameter of the front end of the second thread is larger than the base diameter of the first thread, the base diameter of the second thread is gradually increased from the front end to the middle end, the base diameters of the middle end of the second thread to the third thread and the rear end of the fourth thread are set to be equal, the widths of the first thread, the second thread and the third thread are set to be equal, and the width of the first thread is smaller than the width of the fourth thread.

2. The special extrusion screw for POK according to claim 1, wherein: the diameter of the front end of the feeding section is set to be 26 mm, the diameter of the rear end of the feeding section is set to be 31 mm, the diameter of the front section of the extruding section is set to be 31 mm, and the diameter of the middle end of the extruding section is set to be 35 mm.

3. The special extrusion screw for POK according to claim 1, wherein: first screw thread pitch all establishes 35 millimeters, the screw pitch that the second screw thread is located first section screw pitch rear end all establishes 33 millimeters, third screw thread pitch all establishes 28 millimeters, fourth screw thread pitch all establishes 150 millimeters.

4. The special extrusion screw for POK according to claim 1, wherein: the widths of the first thread, the second thread and the third thread are all set to be 5 millimeters, and the width of the fourth thread is all set to be 6 millimeters.

5. The special extrusion screw for POK according to claim 1, wherein: the feeding section is more than twenty-five and seven percent of the screw body in length, the extruding section is more than twenty-seven percent of the screw body in length, the material-dissolving maintaining section is more than six and eight percent of the screw body in length, and the back pressure section is more than forty and five percent of the screw body in length.

Technical Field

The invention relates to a part of an extruder, in particular to a special extrusion screw for POK.

Background

POK plastic is a novel green polymer material polymerized by CO, ethylene and propylene, has a high-crystallinity and firm crystalline structure and mainly has hydrolysis resistance, impact resistance, abrasion resistance, chemical resistance, fuel resistance and gas barrier property, so that the POK plastic is often produced into bars and then applied to various industries for use.

In the production operation process of the POK plastic bar in the existing screw extruder, raw materials enter a barrel of the screw extruder through a blanking hopper, are heated and melted and then are extruded and molded through a rotating screw, and the POK plastic bar has the characteristics that: the material is easy to burn black, can be carbonized or burned into powder after being heated for a long time, the viscosity of the P0K material in a dissolved state is very high, the tooth depth of the existing extrusion screw is not reasonable enough in design, the raw material enters the machine barrel, the tooth depth of the section is shallow, the viscosity of the P0K material is high, the material is easy to accumulate in the feed port end of the machine barrel to generate large pressure, the material cannot be extruded out after being directly molded in the machine barrel, the material can be clamped in the sleeve to further clamp the screw and twist off the screw, the P0K material is always clamped in the machine barrel, and the material is burnt black and carbonized due to overhigh temperature due to long-time heating, and the P0K material and the P0K material are damaged to cause waste.

Disclosure of Invention

The invention aims to solve the technical problem and provides a special POK extrusion screw which can keep smooth feeding, does not burn black POK materials and does not block the screw.

In order to solve the technical problems, the technical scheme provided by the invention is as follows: the special extrusion screw for the POK comprises a screw head and a screw body, wherein the screw body sequentially comprises a feeding section, an extruding section, a material dissolving section and a back pressure section from front to back, the feeding section comprises a first thread, the thread pitch of the first thread is equal, the extruding section comprises a second thread, the thread pitch of the first section of the second thread is equal to that of the first thread, the thread pitch of the second thread at the back end of the first section of the thread pitch is set to be equal to that of the first section of the thread pitch, the thread pitch of the second thread at the back end of the first section of the thread pitch is greater than that of the first section of the thread pitch, the material dissolving section comprises a third thread, the thread pitch of the third thread is set to be equal to that of the third thread pitch is less than that of the first section of the second thread pitch, the back pressure section comprises a fourth thread, the thread pitch is set to be equal to that of the fourth thread pitch is greater than that of the, first screw thread, second screw thread, third screw thread and fourth screw thread excircle diameter are established to equal, the base footpath of first screw thread increases gradually from preceding backward, the base footpath of the front end of second screw thread is greater than first screw thread base footpath, second screw thread front end to well end base footpath increase gradually, second screw thread well end to third screw thread and fourth screw thread rear end base footpath are established to equal, first screw thread, second screw thread, third screw thread width are established to equal, first screw thread width is less than fourth screw thread width.

Compared with the prior art, the invention has the advantages that: the bottom diameter of the first thread of the feeding section is smaller, namely the thread groove is deeper, so that smooth feeding can be kept, and the situation that the material is blocked due to the fact that the thread groove is shallower, and the POK material is continuously heated at an overhigh temperature and the screw rod body is blocked is avoided; when the feeding section conveys materials for the extrusion section, the bottom diameter is larger along with the fact that the thread groove is shallower, namely the resistance is increased slowly and is equivalent to a transition form to the extrusion section, pressure is further built up by the extrusion section, the materials are compacted and melted, then the end of the extrusion section is conveyed to the material holding section, as the bottom diameter of the material holding section is reduced, the compacted and melted materials can be extruded and easily extruded to the back pressure section to be discharged due to the fact that the thread groove is deeper, the POK materials are prevented from being heated for too long, the fourth thread pitch is increased, pushing pressure can be generated under the action of the large pitch, the POK materials can be conveniently extruded and formed rapidly under the matching of the POK materials, the surfaces of the POK material bars are free of carbon black, and the depths of the thread grooves of the material holding section and the back pressure section can effectively keep the materials from being blackened under the state of.

As a modification, the diameter of the front end of the feeding section is set to be 26 mm, the diameter of the rear end of the feeding section is set to be 31 mm, the diameter of the front section of the extrusion section is set to be 31 mm, and the diameter of the middle end of the extrusion section is set to be 35 mm.

As a refinement, the first thread pitches are set to 35 mm, the second thread pitches located at the rear ends of the first thread pitches are set to 33 mm, the third thread pitches are set to 28 mm, and the fourth thread pitches are set to 150 mm.

As a refinement, the widths of the first thread, the second thread and the third thread are all set to be 5 mm, and the width of the fourth thread is all set to be 6 mm.

As an improvement, the length of the feeding section a accounts for twenty-five-point seven percent of the screw body, the length of the extruding section accounts for twenty-seven percent of the screw body, the material dissolving section accounts for six-point eight percent of the screw body, the back pressure section accounts for forty-five percent of the screw body, the widths of the first thread, the second thread and the third thread are set to be equal, and the width of the first thread is smaller than that of the fourth thread.

Drawings

FIG. 1 is a schematic view of the structure of an extrusion screw for POK of the present invention.

As shown in the figure: 1. a screw head; 2. a screw body; 3. a first thread; 4. a second thread; 5. a third thread; 6. a fourth thread; A. a feeding section; B. a material extruding section; C. maintaining the solvent section; D. and a back pressure section.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

With reference to fig. 1, the special extrusion screw for POK comprises a screw head 1 and a screw body 2, wherein the screw body 2 sequentially comprises a feeding section a, an extruding section B, a material dissolving section C and a back pressure section D from front to back, the feeding section a comprises first threads 3, the thread pitches of the first threads 3 are equal, the extruding section B comprises second threads 4, the thread pitches of the first section of the second threads 4 are equal to the thread pitches of the first threads 3, the thread pitches of the second threads 4 at the rear end of the first section of the thread pitches are equal, the thread pitches of the second threads 4 at the rear end of the first section of the thread pitches are greater than the first section of the thread pitches, the material dissolving section C comprises third threads 5, the thread pitches of the third threads 5 are equal, the thread pitches of the third threads 5 are less than the thread pitches of the first section of the second threads 4, the back pressure section D comprises fourth threads 6, the thread pitches of the fourth threads 6 are equal, the 6 pitches of fourth screw thread are greater than the pitch that second screw thread 4 is located first section pitch rear end, first screw thread 3, second screw thread 4, third screw thread 5 and the 6 excircle diameters of fourth screw thread are established to equal, the end footpath of first screw thread 3 increases from preceding backward gradually, the end footpath is greater than 3 end footpaths of first screw thread at the bottom of the front end of second screw thread 4, 4 front ends of second screw thread to well end footpath increase gradually, 4 middle ends of second screw thread are established to equal at the bottom of third screw thread and the fourth screw thread rear end, first screw thread 3, second screw thread 4, 5 flight widths of third screw thread are established to equal, 3 flight widths of first screw thread are less than 6 flight widths of fourth screw thread.

The diameter of the front end of the feeding section A is set to be 26 mm, the diameter of the rear end of the feeding section A is set to be 31 mm, the diameter of the front section of the extruding section B is set to be 31 mm, and the diameter of the middle end of the extruding section B is set to be 35 mm.

First screw thread 3 pitch all is established to 35 millimeters, the pitch that second screw thread 4 is located first section pitch rear end all establishes to 33 millimeters, 5 pitches of third screw thread all establish to 28 millimeters, 6 pitches of fourth screw thread all establish to 150 millimeters.

The widths of the first thread 3, the second thread 4 and the third thread 5 are set to be 5 mm, and the width of the fourth thread 6 is set to be 6 mm.

The length of the feeding section A accounts for twenty-five-point seven percent of the screw body 2, the length of the extruding section B accounts for twenty-seven percent of the screw body 2, the material dissolving section C accounts for six-point eight percent of the screw body 2, the back pressure section D accounts for forty-five percent of the screw body 2, the thread widths of the first threads 3, the second threads 4 and the third threads 5 are set to be equal, and the thread width of the first threads 3 is smaller than the thread width of the fourth threads 6.

When the continuous heating device is specifically implemented, the bottom diameter of the first thread 3 of the feeding section A is smaller, namely the thread groove is deeper, so that smooth feeding can be kept, and the situation that the material is blocked due to the shallower thread groove, the POK material is continuously heated at too high temperature, and the screw body 2 is stuck is avoided; when the feeding section A conveys materials to the extruding section B, the thread groove is shallower, namely the bottom diameter is larger, namely the resistance is increased slowly and is equivalent to a transition form to the extruding section B, the pressure is further established by the extruding section B, the materials are compacted and melted, then the end of the extruding section B is conveyed to the material holding section C, as the bottom diameter of the material holding section C is reduced, the compacted and melted materials can be extruded to the back pressure section discharging D easily due to the deeper thread groove, the back pressure section D can be discharged quickly, the POK materials are prevented from being heated for too long time, the thread pitch of the fourth thread 6 is increased, the pushing pressure can be generated by the large thread pitch effect, the POK materials can be extruded and formed quickly by matching with the POK materials, the surface of the POK materials is free from carbon black, the thread groove of the material holding section C and the back pressure section D can effectively keep the materials from being burned black and not carbonized under the state of the melting point temperature, the product solves the problems of easy blackening and carbonization of the POK material during material dissolving and the problems of jamming of the screw body 2 and twisting-off prevention of the screw body 2, has the bottom diameter of the bottom of the thread of the threaded rod 2, and is described in front and back directions by referring to the left and right directions in the attached figure 1.

The present invention and its embodiments have been described above, and the description is not intended to be limiting, and the drawings are only one embodiment of the present invention, and the actual structure is not limited thereto. In summary, those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiments as a basis for designing or modifying other structures for carrying out the same purposes of the present invention without departing from the spirit and scope of the invention as defined by the appended claims.