CN115871202A - Gas introduction device and method for molecular orientation tube forming - Google Patents
Gas introduction device and method for molecular orientation tube forming Download PDFInfo
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- CN115871202A CN115871202A CN202211627648.2A CN202211627648A CN115871202A CN 115871202 A CN115871202 A CN 115871202A CN 202211627648 A CN202211627648 A CN 202211627648A CN 115871202 A CN115871202 A CN 115871202A
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- 238000000034 method Methods 0.000 title claims abstract description 12
- 230000007246 mechanism Effects 0.000 claims abstract description 35
- 238000007789 sealing Methods 0.000 claims abstract description 11
- 238000001816 cooling Methods 0.000 claims description 4
- 238000007493 shaping process Methods 0.000 claims description 3
- 238000000465 moulding Methods 0.000 claims 5
- 238000004891 communication Methods 0.000 claims 1
- 239000012530 fluid Substances 0.000 description 4
- 238000011900 installation process Methods 0.000 description 4
- 229920000915 polyvinyl chloride Polymers 0.000 description 4
- 239000004800 polyvinyl chloride Substances 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 229920003023 plastic Polymers 0.000 description 3
- 239000004033 plastic Substances 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000001360 synchronised effect Effects 0.000 description 2
- 241001391944 Commicarpus scandens Species 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 230000009477 glass transition Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
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Abstract
The invention discloses a gas leading-in device and a gas leading-in method for forming a molecular orientation tube, which comprise a product appearance control mechanism, a blank tube and a blank tube control mechanism, wherein the blank tube control mechanism comprises a sealing block, a plug and a guide tube, the guide tube is positioned in the product appearance control mechanism, a regular hollow structure is arranged in the guide tube, one end of the guide tube is open, the other end of the guide tube is closed, a plurality of gas guide small holes are formed in the guide tube from the open end to the closed end, the distance between every two adjacent gas guide small holes is gradually reduced, the blank tube is positioned on the outer surface of the guide tube, the sealing block is clamped in two sides of the product appearance control mechanism, and the plug is connected to one side of the product appearance control mechanism. According to the invention, the guide pipe is provided with the plurality of small air guide holes from the opening end to the closed end, the distance between the adjacent small air guide holes is gradually reduced, and the guide of the oriented gas is divided into three times of guide, so that the wall thickness of the formed pipe can be well controlled, and the biaxial orientation balance of the product is improved.
Description
Technical Field
The invention relates to the technical field of plastic pipe forming, in particular to a gas introducing device and a gas introducing method for forming a molecular orientation pipe.
Background
Biaxial orientation: the PVC-U pipe rearranges the molecules of the material in the axial direction and the radial direction at the glass transition temperature, so that the material (pipe wall) forms a uniform and regular reticular structure, can bear the brittle failure originating from micro cracks of the material body or scratches on the surface of the pipe wall, and obviously improves the strength, the toughness and the anti-cracking performance of the pipe.
The biaxially oriented polyvinyl chloride pipe is manufactured by a special orientation processing technology, and the processing technology is characterized in that a PVC-U pipe produced by an extrusion method is axially stretched and radially stretched, so that PVC long-chain molecules in the pipe are regularly arranged in the axial direction and the radial direction, a novel PVC pipe with high strength, high toughness, high impact resistance and fatigue resistance is obtained, and the performance of the novel PVC pipe is far superior to that of a common PVC-U pipe.
The key of the device and the method for leading the PVC-U pipe to have biaxial orientation to obtain a uniform and regular reticular structure is the gas leading-in device.
There is a prior published patent with the name "apparatus for producing molecularly bi-directional plastic tubes", publication No. CN104162972A, which causes the expansion of the blank tube by uniformly distributing the exit of hot expanding fluid through uniformly distributed orifices on a guide, uniformly ejecting cold fluid through uniformly distributed orifices on the guide over the already expanded tube, exchanging heat with the tube, thereby cooling the shaped tube; the method is mainly characterized in that orifices on the guide device are uniformly distributed, and cold and hot expansion fluid is injected into the space between the PVC-U pipe and the guide device from the orifices on the guide device, so as to orient and cool the PVC-U plastic pipe.
However, this patent causes problems of uneven orientation and large wall thickness variation of the product.
Disclosure of Invention
The invention aims to provide a gas introduction device and a gas introduction method for molecular oriented tube forming, which aim to solve the problems of uneven product orientation and large wall thickness deviation caused by the existing gas forming mode.
The embodiment of the invention is realized by the following technical scheme:
the utility model provides a fashioned gaseous gatherer of directional pipe of molecule, includes product appearance control mechanism, parison tube and parison tube control mechanism, parison tube control mechanism includes sealed piece, end cap and stand pipe, and this stand pipe is located product appearance control mechanism, and this stand pipe is equipped with regular hollow structure inside, and its one end opening, and the other end is sealed, and this stand pipe is equipped with a plurality of air guide apertures from the open end to the blind end, and the distance between this adjacent air guide aperture reduces gradually, and this parison tube is located the stand pipe outer surface, and this sealed piece joint is in product appearance control mechanism both sides, and this end cap is connected in product appearance control mechanism one side.
In an embodiment of the present invention, a relatively closed space may be formed between the parison tube, the sealing block, the plug and the guide tube, and the guide tube is the only path for injecting gas into the closed space, and the plug is the only path for releasing gas from the closed space.
In an embodiment of the present invention, the product shape control mechanism includes a first head portion, a second head portion and a mold forming body, the first head portion, the second head portion and the mold forming body are all provided with inner cavities along an axis, and the first head portion, the mold forming body and the second head portion are detachably connected in sequence along the axis, and the inner cavities are sequentially communicated with each other.
In an embodiment of the invention, the diameter D1 of the inner cavity of the mold form is larger than the diameter D2 of the inner cavities of the first and second heads.
In one embodiment of the invention, there is an initial volume of space between the guide tube and the parison tube.
In an embodiment of the invention, the area of the air guide holes and the arrangement mode of the air guide holes are in a direct proportion relation.
In one embodiment of the present invention, the inner diameter of the product shape control mechanism is 0.4% -0.6% larger than the outer dimension of the product.
A gas introduction method for forming a molecular orientation tube comprises the following steps:
s1: after a closed space is formed among the blank pipe introduced by the introduction device, the sealing block, the plug and the guide pipe, gas with the same temperature as that of the blank pipe is injected into the hollow structure in the guide pipe in an oriented way through an opening at one end of the guide pipe;
s2: and cooling and shaping the oriented blank tube to obtain a biaxial orientation product.
In an embodiment of the present invention, in the step S1, injecting the gas having the same temperature as the parison tube is performed in stages: the first stage, slowly injecting gas to fill the closed space, but not orienting the blank pipe; second stage, injecting orientation-like pressure gas into the filled closed space to orient the blank pipe but not completely orient; and in the third stage, injecting orientation pressure gas into the closed space with similar orientation pressure to completely orient the blank tube.
The technical scheme of the embodiment of the invention at least has the following advantages and beneficial effects:
in the embodiment of the invention, the guide pipe is provided with the plurality of air guide small holes from the opening end to the closed end, the distance between the adjacent air guide small holes is gradually reduced, the area of the air guide small hole is in direct proportion to the number of the air guide small holes, and the guide of the oriented gas is divided into three times of guide, so that the wall thickness of the forming pipe can be well controlled, and the biaxial orientation balance of the product is improved.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and those skilled in the art can also obtain other related drawings based on the drawings without inventive efforts.
FIG. 1 is a schematic cross-sectional view of the blank tube of the present invention prior to orientation;
FIG. 2 is a schematic sectional view of the guide tube according to the present invention;
FIG. 3 is a schematic cross-sectional view of the raw pipe of the present invention;
FIG. 4 is a schematic cross-sectional view of the oriented parison tube of the present invention.
Icon: 1-guide tube, 2-second head, 3-mould forming body, 4-first head, 5-sealing block, 6-plug, 7-original space volume, 8-limiting surface, 9-air guide small hole, 10-hollow structure and 11-blank tube.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined or explained in subsequent figures.
In the description of the present invention, it should be noted that if the terms "inside", "outside", etc. indicate an orientation or a positional relationship based on an orientation or a positional relationship shown in the drawings or an orientation or a positional relationship which is usually placed when the inventive product is used, it is only for convenience of description and simplification of the description, but does not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.
In the description of the present invention, it should be further noted that unless otherwise explicitly stated or limited, the terms "disposed," "installed," "configured," and "connected" should be broadly construed, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Example 1
Referring to fig. 1-4, the present embodiment provides a gas introduction device for molecular orientation tube forming, which includes a product shape control mechanism, a blank tube 11 and a blank tube control mechanism, where the product shape control mechanism includes a first head portion 4, a mold forming body 3 and a second head portion 2, and the first head portion 4, the second head portion 2 and the mold forming body 3 are all provided with inner cavities along an axis, and the first head portion 4, the mold forming body 3 and the second head portion 2 are sequentially detachably connected along the axis, and the inner cavities are sequentially communicated with each other, a diameter D1 of the inner cavity of the mold forming body 3 is greater than a diameter D2 of the inner cavities of the first head portion 4 and the second head portion 2, and the product shape control mechanism is a rigid structure as a whole, and an inner diameter of the product shape control mechanism is greater than a product shape size of 0.4% -0.6%, because the device needs to introduce high-temperature gas to orient the blank tube 11, and then introduce low-temperature gas to cool the blank tube 11, and in this process, the product shape control mechanism can reduce the outer diameter of the product shape control mechanism by a high-precision ratio of the product shape control mechanism to the product size of the product when the blank tube 11 is greater than the product shape control mechanism.
Further, the blank tube control mechanism comprises a sealing block 5, a plug 6 and a guide tube 1, the guide tube 1 is a guide tube 1 which is light and has a deflection smaller than 5/1000, the guide tube 1 is located in the product shape control mechanism, a regular hollow structure 10 is arranged in the guide tube 1 through a second head 2, one end of the guide tube 1 is open, the other end of the guide tube 1 is closed, the open end of the guide tube 1 is also provided with a limiting surface 8, the limiting surface 8 can be matched with the second head 2 to ensure that the guide tube 1 is located at the center of the blank tube 11 and the inside of the mold forming body 3, an original space volume 7 is arranged between the guide tube 1 and the blank tube 11, the original space volume 7 is a gap between the guide tube 1 and the blank tube 11, the gap is used for preventing the blank tube 11 from contacting with the guide tube 1 too much, and preventing the blank tube 11 from contacting with the guide tube 1 to cause the blank tube 11 at the small hole 9 to be too large pressure, so that the blank tube 11 is preferentially oriented, and the forming of the blank tube 11 is affected; the guide tube 1 is provided with a plurality of air guide small holes 9 from the opening end to the closed end, the distance between the adjacent air guide small holes 9 is gradually reduced, the area of the air guide small holes 9 is in a proportional distribution relation with the arrangement mode of the air guide small holes 9, and a certain distance exists between the air guide small holes 9 and the closed end, the air guide small holes 9 from the opening end of the guide tube 1 to the closed end of the guide tube 1 are distributed in a dense arrangement from sparse to dense, the area of the air guide small holes 9 is gradually increased from the opening end of the guide tube 1 to the closed end of the guide tube 1, and the area of the air guide small holes 9 and the arrangement of the air guide small holes 9 are in a proportional distribution, so that the air in the guide tube 1 flows out of the air guide small holes 9 in the same state and size, and the phenomenon of uneven wall thickness of a product is avoided; the sealing block 5 is clamped at two sides in the product shape control mechanism, the plug 6 is positioned at one side outside the product shape control mechanism, relatively closed spaces can be formed among the blank pipe 11, the sealing block 5, the plug 6 and the guide pipe 1 are all rigid structures, the blank pipe 11 is of a soft structure, the guide pipe 1 is the only path for injecting gas into the closed spaces, the plug 6 is the only path for releasing gas in the closed spaces, and the guide pipe 1 is used as the only path for injecting gas into the closed spaces, so that the directionality of oriented gas is determined, and the blank pipe 11 in the closed spaces is ensured to be the only factor which is mutually related to pressure.
The operation steps of the gas leading-in device for forming the molecular orientation tube are as follows:
after the parison tube 11 is introduced into a closed space formed among the device, the sealing block 5, the plug 6 and the guide tube 1, gas with the same temperature as the parison tube 11 is injected into the hollow structure 10 in the guide tube 1 in a directional manner through the opening at one end of the guide tube 1; and the injection of the gas at the same temperature as the billet 11 is performed in stages: in the first stage, slowly injecting gas to fill the closed space, but not to orient the blank pipe 11, so as to buffer the direct impact force of the second stage type oriented gas on the blank pipe 11 and eliminate local uneven orientation; in the second stage, the similar orientation pressure gas is injected into the filled closed space to orient the blank pipe 11 but not completely orient, and the direct impact force of the orientation gas on the blank pipe 11 in the third stage is buffered and the similar orientation pressure is prevented from being too large to cause uneven orientation; in the third stage, the orientation pressure gas is injected into the closed space with similar orientation pressure to completely orient the blank pipe 11; and finally, taking out the blank tube 11 after cooling and shaping to obtain a finished product.
Further, it should be noted that: the gas injection is performed in stages, but there is no significant time interval between stages, and the gas in the closed space is maintained at the same temperature as the temperature of the raw pipe 11 throughout the orientation process.
Example 2
The present embodiment is the same as the installation process of the above-mentioned device, and the operation steps are the same, and the only difference is that the inner diameter of the guiding tube 1 in the present embodiment from the open end to the closed end is uniform, but because the inner diameter of the guiding tube 1 is uniform, the guiding tube 1 can not satisfy the larger and longer device theoretically, because the closed end of the guiding tube 1 needs to bear a pressure much larger than the open end, if the inner diameter is uniform, the blank tube 11 can not be oriented synchronously, and the closed end is easy to break.
Example 3
The present embodiment is the same as the installation process of the above-mentioned device, and the operation steps are the same, and the only difference is that the outer diameter of the guide tube 1 from the open end to the closed end is kept constant and the wall thickness is gradually reduced, i.e. the outer diameter of the guide tube 1 is constant and the inner diameter is gradually increased, i.e. the guide tube 1 is tapered inside, and the tapered structure can realize that the pressure difference borne by the open end and the closed end of the guide tube 1 is smaller, and can realize the synchronous orientation, so that the guide tube 1 can be theoretically suitable for longer and larger devices.
Example 4
The present embodiment is the same as the installation process of the above-mentioned device, and the operation steps are the same, and the only difference is that the outer diameter and the wall thickness of the guide tube 1 in the present embodiment are gradually reduced from the open end to the closed end, i.e. the guide tube 1 is tapered from the open end to the closed end, the tapered structure can realize that the pressure difference borne by the open end and the closed end of the guide tube 1 is smaller, and can realize the synchronous orientation, so that the guide tube 1 can be theoretically suitable for longer and larger devices.
Comparative example
The present comparative example is the same as the installation process of the above-mentioned device, the operation steps are the same, and the only difference is that the guide tube 1 in the present comparative example is that the guide tube 1 is provided with a plurality of air guide holes 9 from the open end to the closed end, and the distance between the adjacent air guide holes 9 is gradually increased, the air guide holes 9 are distributed in the above-mentioned manner, so that when the high-pressure gas directly orients the blank tube 11, the expanding fluid forms a trend of high closed end pressure and low intermediate pressure inside the guide tube 1, the opening mode of the guide tube 1 is consistent with the pressure distribution mode, and the area of the air guide holes 9 is in a positive proportion relation with the arrangement mode of the air guide holes 9, thereby further increasing the pressure difference of the gas flowing out from the air guide holes 9, causing the uneven orientation to be further increased, and further increasing the wall thickness deviation of the product.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made without departing from the spirit and principle of the present invention shall fall within the protection scope of the present invention.
Claims (9)
1. The utility model provides a fashioned gaseous gatherer of directional pipe of molecule, includes product appearance control mechanism, base pipe and base pipe control mechanism, a serial communication port, base pipe control mechanism includes sealed piece, end cap and stand pipe, this stand pipe is located product appearance control mechanism, this stand pipe is equipped with regular hollow structure inside, and its one end opening, the other end is sealed, this stand pipe is equipped with a plurality of air guide apertures from the open end to the blind end, and the distance between this adjacent air guide aperture reduces gradually, this base pipe is located the stand pipe outer surface, and this sealed piece joint is in product appearance control mechanism both sides, this end cap is connected in product appearance control mechanism one side.
2. The gas introduction device for molecular orientation tube molding according to claim 1, wherein the parison tube, the sealing block, the plug and the guide tube form a relatively closed space therebetween, and the guide tube is the only path for injecting gas into the closed space, and the plug is the only path for releasing gas from the closed space.
3. The gas introduction device for molecular orientation tube molding according to claim 1, wherein the product shape control mechanism comprises a first head part, a second head part and a mold molding body, the first head part, the second head part and the mold molding body are all provided with inner cavities along an axis, the first head part, the mold molding body and the second head part are detachably connected in sequence along the axis, and the inner cavities are communicated in sequence.
4. The molecular oriented tube formed gas introduction device according to claim 3, wherein a diameter D1 of the inner cavity of the mold forming body is larger than a diameter D2 of the inner cavities of the first and second heads.
5. The molecular oriented tube formed gas introduction device according to claim 2, wherein an original space volume exists between the guide tube and the parison tube.
6. The molecular orientation tube-forming gas introduction device according to claim 1, wherein the area of the gas guide holes is in direct proportion to the arrangement of the gas guide holes.
7. The molecular oriented tube formed gas introduction device according to claim 1, wherein the inner diameter dimension of the product profile control mechanism is 0.4% -0.6% larger than the outer dimension of the product.
8. A gas introducing method for forming a molecular orientation tube, wherein the gas introducing apparatus for forming a molecular orientation tube as claimed in any one of claims 1 to 7 comprises the steps of:
s1: after a closed space is formed among the blank pipe introduced by the introduction device, the sealing block, the plug and the guide pipe, gas with the same temperature as that of the blank pipe is injected into the hollow structure in the guide pipe in an oriented way through an opening at one end of the guide pipe;
s2: and cooling and shaping the oriented blank tube to obtain a biaxial orientation product.
9. The method of claim 8, wherein the step S1 comprises injecting the gas at the same temperature as the parison tube in stages: the first stage, slowly injecting gas to fill the closed space, but not orienting the blank pipe; second stage, injecting orientation-like pressure gas into the filled closed space to orient the blank pipe but not completely orient; and in the third stage, injecting orientation pressure gas into the closed space with similar orientation pressure to completely orient the blank tube.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211627648.2A CN115871202A (en) | 2022-12-16 | 2022-12-16 | Gas introduction device and method for molecular orientation tube forming |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211627648.2A CN115871202A (en) | 2022-12-16 | 2022-12-16 | Gas introduction device and method for molecular orientation tube forming |
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| CN115871202A true CN115871202A (en) | 2023-03-31 |
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| CN202211627648.2A Pending CN115871202A (en) | 2022-12-16 | 2022-12-16 | Gas introduction device and method for molecular orientation tube forming |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117085378A (en) * | 2023-10-19 | 2023-11-21 | 烟台核信环保设备有限公司 | Improved plastic filter plate and vertical filter press |
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2022
- 2022-12-16 CN CN202211627648.2A patent/CN115871202A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117085378A (en) * | 2023-10-19 | 2023-11-21 | 烟台核信环保设备有限公司 | Improved plastic filter plate and vertical filter press |
| CN117085378B (en) * | 2023-10-19 | 2024-01-02 | 烟台核信环保设备有限公司 | Improved plastic filter plate and vertical filter press |
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