CN218803892U - Double-wall corrugated pipe extrusion die - Google Patents

Abstract

The utility model relates to a double-wall corrugated pipe extrusion die, which is limited with a longitudinal axis and comprises a plasticizing part, a heating part and a mouth die part, wherein the heating part comprises an inner pipe, an intermediate pipe and an outer pipe which are sleeved in turn from inside to outside; the mouth mold part comprises an inner core mold, an intermediate core mold and an outer mouth mold which are respectively and fixedly connected with the inner pipe, the intermediate pipe and the outer pipe; the heating part is characterized in that a plurality of first thread grooves and a plurality of second thread grooves which are circumferentially arranged around a longitudinal axis are formed in the outer pipe of the heating part, a plurality of flat grooves which are circumferentially arranged around the longitudinal axis are formed in the middle pipe, the plurality of flat grooves are aligned with the plurality of second thread grooves in the radial direction respectively, the heating part further comprises an eccentric adjusting mechanism, the eccentric adjusting mechanism comprises a plurality of first adjusting bolts, a plurality of second adjusting bolts and a plurality of sliding parts which are located in the plurality of flat grooves respectively, the bottom of each first adjusting bolt is abutted to the outer pipe of the middle pipe, and the bottom of each second adjusting bolt is abutted to the sliding part in the corresponding flat groove respectively and enables the corresponding sliding part to be in contact with the inner pipe wall.

Description

Double-wall corrugated pipe extrusion die

Technical Field

The utility model belongs to the technical field of plastics are extruded and specifically relates to a double-walled bellows extrusion tooling.

Background

The double-wall corrugated pipe has an outer wall with an annular structure and a smooth inner wall, and is increasingly widely applied to related fields of water supply and drainage, pollution discharge and exhaust and the like due to the physicochemical characteristics of strong external pressure resistance, low engineering cost, light weight, small friction coefficient, low temperature resistance and the like.

The double-wall corrugated pipe extrusion die is used for primarily forming the double-wall corrugated pipe and generally comprises an outer die assembly for forming the outer wall of the double-wall corrugated pipe and an inner die assembly for forming the inner wall of the double-wall corrugated pipe. The outer die assembly comprises an outer wall mouth die and an outer wall core die which are arranged coaxially, and the inner die assembly comprises an inner wall mouth die and an inner wall core die which are arranged coaxially. In the actual work of the double-wall corrugated pipe extrusion die, if the axial lead between the core die and the corresponding die deviates, the pipe wall thickness of the inner wall or the outer wall of the formed double-wall corrugated pipe is different, and the external pressure resistance and the service life of the double-wall corrugated pipe are reduced.

The chinese patent application publication No. CN108284577a discloses a double-wall corrugated pipe mouth mold structure, which has an inner wall eccentric adjusting bolt and an outer wall eccentric adjusting bolt for adjusting the axial leads of an inner wall core mold and an outer wall core mold, respectively. However, the provision of the above-mentioned eccentric adjustment bolt at the die has the following adverse effects:

1. each eccentric adjusting bolt is close to the corresponding discharge hole, and the inner pipe wall material or the outer pipe wall material leaves clear visible weld marks on the inner wall or the outer wall of the formed double-wall corrugated pipe after flowing through the corresponding eccentric adjusting bolt. When the double-wall corrugated pipe is subjected to external pressure, the weld marks are easily broken, which reduces the external pressure resistance of the corrugated pipe.

2. In order to make the inner wall adjusting bolt abut against the inner wall core mould better, the inner core mould and the outer core mould need to be provided with a section of horizontal section, so that the inner feeding channel and the outer feeding channel of the mouth mould part are provided with a horizontal flow channel section. The horizontal flow passage section increases the local pressure loss of the materials on the inner wall and the outer wall, thereby reducing the outlet pressure of the materials and the connection reliability of the inner wall and the outer wall of the double-wall corrugated pipe after forming.

3. Because the inner wall adjusting bolt is positioned at the rear side of the outer die assembly, the extrusion die needs to be stopped when the axis position of the inner wall core die is adjusted, so that the outer die assembly is stopped from outputting the outer pipe wall material.

SUMMERY OF THE UTILITY MODEL

To the defect part that above-mentioned sets up eccentric adjusting bolt in bush portion, the utility model provides a novel double-walled bellows extrusion tooling, the eccentric adjustment mechanism of this double-walled bellows keeps away from bush portion.

In order to achieve the above object, the present invention provides the following technical solutions: a double-wall corrugated pipe extrusion die is limited with a longitudinal axis and comprises a plasticizing part, a heating part and a die part which are sequentially arranged along the longitudinal axis, wherein the heating part comprises an inner pipe, a middle pipe and an outer pipe which are sequentially sleeved from inside to outside, an inner heating channel is limited by the inner pipe and the middle pipe, and an outer heating channel is limited by the middle pipe and the outer pipe; the mouth mold part comprises an inner core mold, an intermediate core mold and an outer mouth mold which are respectively fixedly connected with the inner pipe, the intermediate pipe and the outer pipe, the inner core mold and the intermediate core mold jointly limit an inner discharging channel communicated with the inner heating channel, and the intermediate core mold and the outer mouth mold jointly limit an outer discharging channel communicated with the outer heating channel; the heating part is provided with an eccentric adjusting mechanism, the eccentric adjusting mechanism comprises a plurality of first adjusting bolts respectively in threaded connection with the first threaded grooves, a plurality of second adjusting bolts respectively in threaded connection with the second threaded grooves, and a plurality of sliding pieces respectively located in the flat grooves, the bottom of each first adjusting bolt abuts against the outer pipe of the middle pipe, and the bottom of each second adjusting bolt abuts against the corresponding sliding piece in the flat groove and enables the corresponding sliding piece to be in contact with the pipe wall of the inner pipe.

In the above technical solution, preferably, each of the first thread grooves and each of the second thread grooves are located on the same radial plane.

In the above technical solution, preferably, the plurality of first thread grooves and the plurality of second thread grooves are all configured to be arranged circumferentially at equal intervals around the longitudinal axis.

In the above-described aspect, it is preferable that the outer tube of the heating portion has a total of four first thread grooves and four second thread grooves. It is further preferable that the first thread groove and the second thread groove are alternately arranged in sequence.

In the above technical solution, preferably, each of the first adjusting bolt and the second adjusting bolt has a nut exposed from the outer tube, a threaded portion screwed with the corresponding threaded groove, and an abutting portion located below the threaded portion and at least partially extending into the outer heating channel.

Compared with the prior art, the utility model discloses double-walled bellows extrusion tooling that technical scheme provided sets up eccentric adjusting structure in order to keep away from a mouthful mould portion on heating portion to avoid leaving the weld mark on the double-walled bellows after the shaping. In addition, the arrangement does not require the extrusion die to be shut down when adjusting the axis of the inner core die.

Drawings

Fig. 1 is a side view of a double-wall corrugated pipe extrusion die provided by the present invention;

FIG. 2 isbase:Sub>A cross-sectional view of the double-wall corrugated pipe extrusion die of FIG. 1 taken along direction A-A;

FIG. 3 is an enlarged view of a portion of FIG. 2 at B;

FIG. 4 is an enlarged view of a portion of FIG. 2 at C;

FIG. 5 is a schematic side view of an eccentric adjustment mechanism of the double-walled bellows extrusion die of FIG. 1;

FIG. 6 is a cross-sectional view of a die portion of the double-walled bellows extrusion die of FIG. 1;

FIG. 7 is an enlarged view of a portion of FIG. 6 at D; wherein, the included angle formed by each annular inclined surface and the longitudinal axis is shown in the figure.

100. A double-wall corrugated pipe extrusion die;

1. a plasticizing part; 11. an inner spiral shaft sleeve; 111. a first helical groove; 112. an internal plasticizing channel;

12. an external spiral shaft sleeve; 121. a second helical groove; 122. an outer plasticizing channel;

13. an outer defining sleeve; 14. an end cap; 15. a first feed conduit; 16. a second feed conduit;

2. a heating section; 21. an inner tube; 22. an intermediate pipe; 221. flattening the groove; 23. an outer tube; 231. a first thread groove; 232. a second thread groove; 24. an internal heating channel; 25. an external heating channel; 26. a first heating ring;

3. a die section; 31. an inner core mold; 311. a first annular inclined surface;

32. an intermediate core mold; 321. a second annular bevel; 322. a third annular chamfer;

33. an outer die; 331. a fourth annular bevel; 34. an inner discharge channel; 35. an outlet material channel; 36. a second heating ring;

41. a first adjusting bolt; 42. a second adjusting bolt; 43. a slider;

y, longitudinal axis line; alpha 1, a first included angle; alpha 2 and a second included angle; α 3, a third angle; α 4, fourth angle.

Detailed description of the preferred embodiments

To explain the technical content, structural features, attained objects and functions of the present invention in detail, the technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are only some embodiments of the present application, and not all embodiments. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a detailed description of various exemplary embodiments or modes of practice of the invention. However, various exemplary embodiments may be practiced without these specific details or with one or more equivalent arrangements. Moreover, the various exemplary embodiments may be different, but are not necessarily exclusive. For example, the particular shapes, configurations and characteristics of the exemplary embodiments may be used or implemented in another exemplary embodiment without departing from the inventive concept.

Further, in this application, spatially relative terms such as "below … …", "below … …", "below … …", "below", "above … …", "above … …", "higher", "side" (e.g., as in "side wall"), etc., thus describe the relationship of one element to another (other) element as shown in the figures. Spatially relative terms are intended to encompass different orientations of the device in use, operation, and/or manufacture in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "below … …" may include both an orientation of above and below. Further, the devices may be otherwise positioned (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

In the present invention, the term "head" means the most upstream end of a channel, groove or solid part, in terms of the direction of flow of the material; the term "tail" means the most downstream end of a channel, groove or solid component with respect to the direction of flow of the material.

Fig. 1-2 illustrate a double-walled bellows extrusion die 100 (hereinafter referred to as an extrusion die) provided by the present invention, the extrusion die 100 being adjacent downstream of a corresponding extruder to receive molten bellows material (including inner and outer tube wall material). As shown, the extrusion die 100 defines a longitudinal axis Y extending forward and rearward, and includes a plasticizing part 1, a heating part 2, and a die part 3, which are sequentially disposed along the longitudinal axis Y.

The plasticizing part 1 is used for receiving molten corrugated pipe material and performing primary plasticizing enhancement on the material. Referring to fig. 3, the plasticizing part 1 is fixedly supported on a frame 4, and the plasticizing part 1 includes an inner spiral sleeve 11, an outer spiral sleeve 12 and an outer limiting sleeve 13, which are sequentially sleeved from inside to outside and extend along a longitudinal axis Y. The outer wall of the inner spiral shaft sleeve 11 is provided with a plurality of first spiral grooves 111 extending along the longitudinal axis Y in a spiral posture, and each first spiral groove 111 is configured to gradually decrease in groove depth along the flowing direction of the inner pipe wall material. The inner spiral sleeve 11 and the outer spiral sleeve 12 together define an inner plasticizing passage 112, and the plurality of first spiral grooves 111 form a part of the inner plasticizing passage 112. After the inner pipe wall material enters the extrusion die 100, the inner pipe wall material is divided into a plurality of material flows by the plurality of first spiral grooves 111 at the head part of the inner plasticizing channel 112 and moves spirally, and then the plurality of material flows are combined into one flow at the tail parts of the plurality of first spiral grooves 111, so that the primary reinforcing and plasticizing of the material are completed.

The outer wall of the outer spiral sleeve 12 is opened with a plurality of second spiral grooves 121 extending along the longitudinal axis Y in a spiral posture, and each second spiral groove 121 is configured such that the groove depth gradually decreases along the direction of the material flow. The outer swivel sleeve 12 and the outer defining sleeve define an outer plasticizing passage 122, and the plurality of second helical grooves 121 form a portion of the outer plasticizing passage 122. Similarly, after the material of the outer tube wall enters the extrusion die 100, the material is divided into a plurality of material flows by the second spiral grooves 121 at the head of the outer plasticizing channel 122 and moves spirally, and then the plurality of material flows are merged into one flow at the tail of the second spiral grooves 121, so that the preliminary reinforcing and plasticizing of the material are completed.

With continued reference to fig. 1, the extrusion die 100 further includes an end cap 14 disposed at the plasticizing portion 1, a first feed conduit 15, and a second feed conduit 16. The end cap 14 is used to enclose the front portions of the inner spiral sleeve 11, the outer spiral sleeve 12 and the outer limiting sleeve 13, and the first and second feed conduits are used to feed the inner and outer wall materials into the inner and outer plasticizing channels 112 and 122, respectively.

As shown in fig. 2, the heating unit 2 is used for continuously heating the corrugated pipe material, the heating unit 2 includes an inner pipe 21, an intermediate pipe 22, and an outer pipe 23, which are sequentially sleeved from inside to outside, and the inner pipe 21, the intermediate pipe 22, and the outer pipe 23 all extend along a longitudinal axis Y. The head of the inner tube 21 and the head of the middle tube 22 are respectively connected with the tail of the inner spiral shaft sleeve 11 and the tail of the outer spiral shaft sleeve 12 by fasteners. The inner pipe 21 and the middle pipe 22 define an inner heating channel 24 for the inner pipe wall material to flow, and the head of the inner heating channel 24 is communicated with the tail of the inner plasticizing channel 112. The head of the outer pipe 23 is fixedly connected with the tail part of the outer limiting shaft sleeve 13, the inner wall surface of the outer pipe 23 and the outer wall surface of the middle pipe 22 jointly define an outer heating channel 25 for the material of the outer pipe wall to flow, and the head of the outer heating channel 25 is communicated with the tail part of the outer plasticizing channel 112. The heating part 2 is provided with a plurality of first heating rings 26 which are tightly sleeved on the outer pipe 23 from the periphery at intervals so as to continuously heat the corrugated pipe materials in the inner and outer heating channels.

Referring to fig. 6, the mouthpiece section 3 includes an inner core mold 31, an intermediate core mold 32, and an outer mouthpiece 33, which are sequentially fitted from inside to outside. The head of the inner core mold 31 and the head of the intermediate core mold 32 are fixedly connected to the tail of the inner tube 21 and the tail of the intermediate tube 22, respectively. The outer wall surface of the inner core mold 31 and the inner wall surface of the intermediate core mold 32 together define an inner tapping channel 34 communicating with the inner heating channel 24, and the inner plasticizing channel 112, the inner heating channel 24 and the inner tapping channel 34 form an inner material flow path for the inner pipe wall material to flow into and out of the extrusion die 100. The head of the outer mouth mold 33 is fixedly connected with the tail of the outer tube 23, the inner wall surface of the outer mouth mold 33 and the outer wall surface of the intermediate core mold 32 jointly define an outer material outlet channel 35 communicated with the outer heating channel 25, and similarly, the outer plasticizing channel 122, the outer heating channel 23 and the outer material outlet channel 35 form an outer material flow path for the material of the outer tube wall to flow into and out of the extrusion die 100. Wherein, the mouth mold part 3 is also provided with a second heating ring 36 wrapping the outer mouth mold 33 from the outside so as to maintain the temperature and the flowing state of the corrugated pipe material in the mouth mold part 3.

For guaranteeing the concentricity between interior mandrel 31, middle mandrel 32 and the 33 three of outer bush, guarantee that the wall thickness of pipe wall and outer pipe wall is even in the double-walled bellows promptly, the utility model discloses heating portion 2 at extrusion tooling 100 is provided with eccentric adjustment mechanism. Referring to fig. 4 to 5, in the extrusion die 100 provided in this embodiment, four first thread grooves 231 and four second thread grooves 232 are formed on the outer tube 23 of the heating portion 2, the first thread grooves 231 are arranged circumferentially at equal intervals, and the first thread grooves and the second thread grooves penetrate through the outer tube 23 and are sequentially arranged at intervals in a staggered manner. The intermediate pipe 22 is provided with four flat grooves 221 which are arranged circumferentially at equal intervals and penetrate through the intermediate pipe 22, each first thread groove 231, each second thread groove 232 and each flat groove 221 are located on the same radial plane, and the four flat grooves 221 are configured to be aligned with the four second thread grooves 232 in the radial direction.

The eccentric mechanism includes first adjusting bolts 41 respectively located at the four first screw grooves 231, four second adjusting bolts 42 respectively located at the four second screw grooves 232, and four sliders 43 respectively located within the four flat grooves 221. Each slide 43 is in sliding connection with a respective flat slot 221. The first and second adjusting bolts each comprise a nut (not shown) exposed from the outer tube 23 for rotation by a user, a threaded portion (not shown) in threaded engagement with a corresponding helical groove, and an abutment (not shown) located below the threaded portion and extending at least partially into the outer heating channel 25. Wherein the abutment portions of the four first adjusting bolts 41 are all abutted to the outer wall of the intermediate tube 22, and the abutment portions of the four second adjusting bolts 42 are abutted to the outer surfaces of the respective sliding members 43 and bring the respective sliding members 43 into contact with the wall surface of the inner tube 21. It can be understood that the position of the axial line of the inner core mold 31 and the intermediate core mold 32 can be adjusted by the first and second adjusting bolts, so as to ensure the uniformity of the wall of the formed double-wall corrugated pipe. In other embodiments, any number of first and second adjusting bolts can be arranged, but in order to ensure that the axial lead positions of the inner core mould and the intermediate core mould can be adjusted in all directions, the number of the first adjusting bolts and the second adjusting bolts is not less than three; in other embodiments, the first and second thread grooves may be disposed in different radial planes, but it is understood that the second thread groove and the flat groove should be disposed in the same radial plane.

The extrusion die 100 provided by this embodiment has the eccentric adjusting mechanism disposed on the heating portion 2, so that each adjusting bolt can be far away from the outlet of the die portion 3, thereby avoiding the melting and connecting trace left on the inner wall or/and the outer wall of the formed double-wall corrugated pipe, and ensuring the external pressure resistance of the double-wall corrugated pipe. Further, since the eccentric mechanism is located on the front side of the die section 3, the extrusion die 100 can be operated without stopping when the axial position of the inner core die 31 and the intermediate core die 32 is adjusted.

In addition, thanks to the above design, the present invention provides an extrusion die 100 that can eliminate the horizontal runner section located in the die portion 3.

Specifically, referring to fig. 6 to 7, the inner core mold 31 in this embodiment has a first annular inclined surface 311 formed on the outer wall surface; a second annular inclined surface 321 and a third annular inclined surface 322 are formed on the inner wall surface and the outer wall surface of the intermediate core mold 32, respectively; the inner wall surface of the outer die 33 forms a fourth annular inclined surface 331, and the first, second, third, and fourth annular inclined surfaces are all inclined rearward and outward. The inner channel 34 is formed by a first and a second annular inclined surface, and the outer channel 35 is formed by a third and a fourth annular inclined surface. It can be understood that, the inner and outer material channels are both linear inclined channels, and compared with the material discharge channel in the prior art, the inner and outer material channels provided in this embodiment have smaller overall pressure loss, and the corrugated pipe material still has larger overall pressure (including dynamic pressure and static pressure) after passing through the inner and outer material channels, thereby ensuring that the inner and outer pipe walls of the formed double-wall corrugated pipe are firmly combined. Wherein, an inner discharge port (not labeled in the figure) for the inner pipe wall material to flow out of the extrusion die 100 is formed at the tail part of the inner discharge channel 34, and an outer discharge port (not labeled in the figure) for the outer pipe wall material to flow out of the extrusion die 100 is formed at the tail part of the outer discharge channel 35.

Further, the inner and outer feed channels are configured such that the channel depth decreases gradually along the direction of material flow. Wherein, the first annular inclined surface 311 forms a first included angle α 1 with the longitudinal axis Y (the included angle formed by any generatrix of the annular inclined surface and the longitudinal axis Y is taken as the reference, and the following is the same); the second annular inclined surface 321 forms a second included angle α 2 smaller than the first included angle α 1 with the longitudinal axis Y; the third annular inclined surface 322 forms a third included angle α 3 with the longitudinal axis Y; the fourth annular inclined surface 331 forms a fourth included angle α 4 smaller than the third included angle α 3 with the longitudinal axis Y. Still further, the first included angle α 1 is larger than the third included angle α 3, so that the inner pipe wall material at the inner discharge port rushes towards the outer pipe wall material at the outer discharge port, which is beneficial to the combination of the inner pipe wall material and the outer pipe wall material.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are given by way of illustration only, and that various changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims, specification and equivalents thereof.

Claims (6)

1. A double-wall corrugated pipe extrusion die is limited with a longitudinal axis and comprises a plasticizing part, a heating part and a die part which are sequentially arranged along the longitudinal axis, and is characterized in that the heating part comprises an inner pipe, a middle pipe and an outer pipe which are sequentially sleeved from inside to outside, an inner heating channel is limited by the inner pipe and the middle pipe, and an outer heating channel is limited by the middle pipe and the outer pipe; the mouth mold part comprises an inner core mold, an intermediate core mold and an outer mouth mold which are respectively fixedly connected with the inner pipe, the intermediate pipe and the outer pipe, the inner core mold and the intermediate core mold jointly limit an inner discharging channel communicated with the inner heating channel, and the intermediate core mold and the outer mouth mold jointly limit an outer discharging channel communicated with the outer heating channel; the heating part is provided with an eccentric adjusting mechanism, the eccentric adjusting mechanism comprises a plurality of first adjusting bolts respectively in threaded connection with the first threaded grooves, a plurality of second adjusting bolts respectively in threaded connection with the second threaded grooves, and a plurality of sliding pieces respectively located in the flat grooves, the bottom of each first adjusting bolt abuts against the outer pipe of the middle pipe, and the bottom of each second adjusting bolt abuts against the corresponding sliding piece in the flat groove and enables the corresponding sliding piece to be in contact with the pipe wall of the inner pipe.

2. A double-walled bellows extrusion die according to claim 1, wherein each of said first thread grooves and each of said second thread grooves are located on the same radial plane.

3. A double-walled bellows extrusion die according to claim 1, wherein the first plurality of helical grooves and the second plurality of helical grooves are each configured to be arranged circumferentially equidistant about the longitudinal axis.

4. A double-walled corrugated pipe extrusion die as claimed in claim 1, wherein the outer tube of said heating portion is formed with four said first thread grooves and four said second thread grooves.

5. A double-wall corrugated pipe extrusion die as claimed in claim 4, wherein the first thread grooves and the second thread grooves are alternately arranged in sequence.

6. A double-walled bellows extrusion die according to claim 1, wherein each of said first adjusting bolt and said second adjusting bolt has a nut outwardly exposed from said outer tube, a threaded portion threadedly coupled to a corresponding one of said threaded grooves, and an abutment portion located on a lower side of said threaded portion and at least partially protruding into said outer heating channel.

Images