CN109605720B - Inner cooling structure of plastic film blowing machine - Google Patents
Inner cooling structure of plastic film blowing machine Download PDFInfo
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- CN109605720B CN109605720B CN201810363480.6A CN201810363480A CN109605720B CN 109605720 B CN109605720 B CN 109605720B CN 201810363480 A CN201810363480 A CN 201810363480A CN 109605720 B CN109605720 B CN 109605720B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C55/00—Shaping by stretching, e.g. drawing through a die; Apparatus therefor
- B29C55/28—Shaping by stretching, e.g. drawing through a die; Apparatus therefor of blown tubular films, e.g. by inflation
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
- B29C35/16—Cooling
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
- B29C35/16—Cooling
- B29C2035/1658—Cooling using gas
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- Shaping By String And By Release Of Stress In Plastics And The Like (AREA)
- Extrusion Moulding Of Plastics Or The Like (AREA)
Abstract
An inner cooling structure of a plastic film blowing machine comprises a cylindrical film blowing die head, a vertical inner air pipe and a vertical outer air pipe, wherein an annular outer ring wall is further arranged above the film blowing die head, a plurality of air outlet small holes are formed in the annular outer ring wall, the top of the annular outer ring wall is connected with a circular top cover plate, an annular inner ring wall is further arranged inside the annular outer ring wall, a plurality of air permeable small holes are formed in the ring wall, an annular partition plate is covered at the top of an inner ring-shaped air cavity, a plurality of air exhaust holes are further formed in the annular partition plate, each air exhaust hole is correspondingly connected with an air exhaust pipe, and the extending direction of the upper section of each air exhaust pipe is obliquely crossed with the horizontal plane; and a circular upper wall plate is also arranged above the circular top cover plate. The invention can improve the cooling effect of the film bubble.
Description
Technical Field
The invention belongs to the technical field of plastic film blowing machines, and particularly relates to an inner cooling structure of a plastic film blowing machine.
Background
The plastic film can be produced by a blown film process. In the production process, the plastic melt is extruded upwards from the circular extrusion port 101 of the film blowing die head 10 to form a film bubble, as shown in fig. 1, the film bubble 8 is drawn to move upwards continuously, and the cooling mechanism located beside the film bubble 8 blows cooling air continuously to cool the film bubble 8, so that the film bubble 8 is condensed. The cooling mode is divided into an external cooling mode and an internal cooling mode, the external cooling mode adopts an external cooling air ring 102, the external cooling air ring 102 is positioned at the outer side of the film bubble 8, and cooling air flow in the centripetal direction is blown out to cool the film bubble 8 from the outside; the inner cooling mode is subdivided into two forms of an inner cooling air ring and an annular wall with small air outlet holes, the inner cooling air ring and the annular wall are both positioned on the inner side of the film bubble, and cooling air flow in the centrifugal direction is blown out from the annular air outlet and is cooled from the inside of the film bubble. Wherein the inner cooling air ring is provided with a circular air outlet.
The existing annular wall adopting small air outlet holes is structurally shown in figure 1 and comprises a cylindrical film blowing die head 10, a vertical inner air duct 1 and a vertical outer air duct 2, wherein a blower and an exhaust fan are arranged outside the film blowing die head 10, the walls of the inner air duct 1 and the outer air duct 2 are airtight, the inner air duct 1 and the outer air duct 2 downwards penetrate through the central position of the film blowing die head 10, the central axes of the inner air duct 1 and the outer air duct 2 are overlapped with the central axis of the film blowing die head 10, the inner air duct 1 and the outer air duct 2 form a concentric relation in the horizontal projection position, the outer air duct 2 is sleeved outside the inner air duct 1, and the inner air duct 1 upwards extends to the upper part of the film blowing die head 10 from the central position of the film blowing die head 10; an inner annular air cavity 12 is formed between the inner air pipe 1 and the outer air pipe 2; a circular ring-shaped annular wall 4 is also arranged on the periphery of the upper section of the inner air pipe 1 (the annular wall 4 is positioned on the periphery of the upper section of the inner air pipe 1, so the annular wall is called as an outer annular wall 4); the central axis of the outer ring wall 4 is also overlapped with the central axis of the film blowing die head 10, a plurality of small air outlet holes 41 are densely arranged on the outer ring wall 4, the small air outlet holes 41 are uniformly distributed on the outer ring wall 4 and the vertical circumference, the bottom edge of the outer ring wall 4 is close to the upper surface of the film blowing die head 10, the top of the circular outer ring wall 4 is connected with a circular top cover plate 7, and the diameter of the circular top cover plate 7 is equal to that of the circular outer ring wall 4; the inner air pipe 1 upwards penetrates through the circular top cover plate 7; an upper annular air cavity 32 is formed between the annular outer ring wall 4 and the inner air pipe 1, and the top end of the inner annular air cavity 12 is communicated with the upper annular air cavity 32. When the device works, the film bubble 8 is extruded from the circular extrusion port 101 of the film blowing die head 10, moves upwards and passes through the periphery of the circular outer ring wall 4; the blower is communicated with the bottom end of the inner annular air cavity 12, and the inner annular air cavity 12 is formed into an air inlet channel; the exhaust fan is communicated with the bottom end of the inner air pipe cavity 11, and the inner air pipe cavity 11 forms an air outlet channel; the cooling air flow goes upward from the inner layer annular air cavity 12, enters the upper annular air cavity 32 and is blown out from the plurality of small air outlet holes 41 on the annular outer ring wall, so that the inner surface of the film bubble 8 is cooled; then, the air flow goes upward to the top of the inner air duct 1, is sucked into the lumen 11 of the inner air duct, and is drawn out from the lower end of the inner air duct.
The cooling efficiency of the internal cooling structure of the plastic film blowing machine adopting the internal cooling ring wall is still to be improved, and the internal cooling structure has the following two reasons:
firstly, when the film blowing die head works, the temperature of the film blowing die head reaches about 200 ℃, the air inlet channel 12 is directly close to the film blowing die head 10, and the temperature of cooling air flow can be greatly increased when the cooling air flow flows through the center of the film blowing die head 10. Even if the heat insulating material is arranged on the air inlet channel, the temperature of the heat insulating material can rise to be close to that of the film blowing die head after the heat insulating material works for a period of time, so that the heat insulating material cannot effectively prevent the cooling air flow from greatly rising;
secondly, the sucked air flow is short cut near the top of the inner air duct inside the bubble, for example, in fig. 1, the air flow moves along the path of a → B → C, but does not move along the path of a → B → E → C, or even moves along the path of a → B → E → G → C, which means that the air at the top of the bubble (such as the portion near the triangle EFG in fig. 1) is generally difficult to suck away, but stays on the top of the bubble for a long time, approaches the dead angle where the air flow is formed, causes the air temperature at the portion to be high, affects the cooling effect, and also causes the following unreasonable phenomena: the air pumped out of the film bubble is not the air with the highest temperature, and the air with the highest temperature cannot be sucked out in time, so that the cooling effect of the film bubble can be influenced.
Thirdly, in the upper annular air cavity 32, because the cooling air flow is discharged from the small air outlet holes 41 while rising, the pressure of the cooling air flow rapidly falls along the vertical direction, and the pressure of the cooling air flow rapidly falls along with the rising of the height, the pressure is not uneven, and specifically, in fig. 1, the air pressure at the upper point S is much lower than that at the lower point R.
Disclosure of Invention
The invention aims to overcome the defects and provide an inner cooling structure of a plastic film blowing machine, which can improve the cooling effect of film bubbles.
The purpose can be realized according to the following scheme: the inner cooling structure of the plastic film blowing machine comprises a cylindrical film blowing die head, a vertical inner air pipe and a vertical outer air pipe, wherein a blower and an exhaust fan are arranged outside the film blowing die head; an annular outer ring wall is arranged above the film blowing die head, the bottom edge of the outer ring wall is close to the upper surface of the film blowing die head, and the central axis of the outer ring wall is also overlapped with the central axis of the film blowing die head; the annular outer ring wall is provided with a plurality of small air outlet holes which are uniformly distributed in the circumferential direction of the annular outer ring wall, and the inner diameter of the annular outer ring wall is larger than the outer diameter of the outer air pipe; the top of the circular outer ring wall is connected with a circular top cover plate, and the diameter of the circular top cover plate is equal to that of the circular outer ring wall; the top end of the cavity of the inner air pipe is open, the top end of the inner air pipe is lower than the circular top cover plate, and a vertical distance is formed between the top end of the inner air pipe and the circular top cover plate; the outer air pipe also extends upwards to the position above the film blowing die head from the center of the film blowing die head, and the vertical position of the top end of the outer air pipe is flush with the vertical position of the top end of the inner air pipe; the central part of the circular top cover plate is in a conical tip shape with a large upper part and a small lower part, a circular inner ring wall is also arranged in the circular outer ring wall, the diameter of the inner ring wall is larger than that of the outer air pipe and smaller than that of the circular outer ring wall, the top edge of the inner ring wall is connected with the top cover plate, and the bottom edge of the inner ring wall is close to the upper surface of the film blowing die head; the inner annular wall is provided with a plurality of small air holes, the small air holes are uniformly distributed in the circumferential direction of the inner annular wall, but the small air holes are not uniformly distributed in the vertical direction of the inner annular wall, and the smaller the position of the small air holes is, the denser the position of the small air holes is; an annular inner layer annular air cavity is formed between the inner air pipe and the outer air pipe; a circular middle layer annular air cavity is formed between the outer air pipe and the inner annular wall, and a circular outer layer annular air cavity is formed between the inner annular wall and the outer annular wall; the blower is communicated with the bottom end of the pipe cavity of the inner air pipe, and the pipe cavity of the inner air pipe forms an air inlet channel; the exhaust fan is communicated with the bottom end of the inner-layer annular air cavity, and the inner-layer annular air cavity is formed into an air outlet channel; the top of the inner layer annular air cavity is covered with an annular clapboard, and the vertical position of the annular clapboard is lower than that of the top cover plate; the central circular hole of the circular ring-shaped partition plate is aligned with the upper port of the inner air pipe; the vertical position of the air-permeable small hole on the uppermost part of the inner ring wall is lower than the annular clapboard; the circular ring-shaped partition plate is also provided with a plurality of air exhaust holes, the air exhaust holes are uniformly distributed along the circumferential direction of the circular ring-shaped partition plate, each air exhaust hole is correspondingly connected with one air exhaust pipe, and each air exhaust pipe upwards penetrates through the circular top cover plate; the exhaust pipe is divided into an upper exhaust pipe section and a lower exhaust pipe section, wherein the upper exhaust pipe section is positioned above the top cover plate, and the lower exhaust pipe section is positioned between the top cover plate and the annular partition plate; an air inlet gap is formed between the lower sections of the exhaust pipes of every two adjacent exhaust pipes; the upper sections of the exhaust pipes form a rotational symmetry relation with the central axis of the film blowing die head; the extending direction of the upper section of each section of exhaust pipe forms oblique intersection with the horizontal plane, and the distance from the upper end of the upper section of the exhaust pipe to the central axis of the film blowing die head is greater than the distance from the lower end of the upper section of the exhaust pipe to the central axis of the film blowing die head; on the horizontal projection plane, the extending direction of the upper section of each exhaust duct and the radial direction of the central point of the lower end of the upper section of the exhaust duct form an included angle of 45-90 degrees; the upper part of the circular top cover plate is also provided with a circular upper wall plate, the central axis of the circular upper wall plate is overlapped with the central axis of the film blowing die head, the height of the circular upper wall plate is larger than that of the upper section of the exhaust pipe, and the radius of the circular upper wall plate is larger than the eccentric distance of the upper end of the upper section of the exhaust pipe.
The rotationally symmetrical relationship means a relationship in which, if one of the members is rotated about the central axis of the blown film die (referred to as a symmetry axis or a rotation axis) among the plurality of members arranged about the central axis of the blown film die, the member coincides with the position and shape of the other member every time the member is rotated by an angle of 360 °/n (n is a positive integer greater than 1), and the relationship is referred to as a rotationally symmetrical relationship.
The lower end of the upper section of the exhaust duct refers to the junction part of the upper section of the exhaust duct and the circular top cover plate, namely the junction part of the upper section of the exhaust duct and the lower section of the exhaust duct.
The radial direction of the central point of the lower end of the upper section of the exhaust pipe refers to the diameter direction of the top cover plate passing through the central point of the lower end of the upper section of the exhaust pipe.
The eccentric distance of the upper end of the upper section of the exhaust pipe refers to the horizontal distance from the upper end of the upper section of the exhaust pipe to the central axis of the film blowing die head.
The eccentric distance between the lower end of the upper section of the exhaust pipe and the central axis of the film blowing die head is the horizontal distance between the lower end of the upper section of the exhaust pipe and the central axis of the film blowing die head.
The invention has the following advantages and effects:
when the cooling device works, cooling airflow flows upwards from the pipe cavity of the inner air pipe to the upper part of the pipe cavity of the inner air pipe, then enters the middle-layer annular air cavity through the air inlet gap between the lower sections of every two adjacent exhaust pipes, then the cooling airflow of the middle-layer annular air cavity goes downwards, gradually enters the outer-layer annular air cavity through the small air holes in the inner annular wall along the way, and finally is blown out from the small air outlet holes in the outer-layer annular air cavity, so that the inner surface of the film bubble is cooled; then, the high-temperature airflow ascends to reach the top of the film bubble, is sucked into the inner-layer annular air cavity, flows downwards, and is finally drawn away from the lower end of the inner-layer annular air cavity, and the process has the following advantages:
firstly, a pipe cavity of the inner air pipe is formed into an air inlet channel; the inner layer annular air cavity is formed into an air outlet channel, so that the air inlet channel and the film blowing die head are separated by the inner layer annular air cavity, the temperature of the film blowing die head cannot be directly transmitted to the cooling air flow of the air inlet channel and can only be directly transmitted to the air of the air outlet channel, but the air of the air outlet channel can be immediately discharged, and the temperature of the cooling air flow of the air inlet channel is basically not influenced by the film blowing die head;
the upper sections of the exhaust pipes form a rotational symmetry relation with the central axis of the film blowing die head, and the extension direction of the upper sections of the exhaust pipes and the radial direction of the central point of the lower end of the upper sections of the exhaust pipes form an included angle of 45-90 degrees; thus, the direction of the air flow sucked into the exhaust pipe at the upper part of the film bubble is not along the radial direction or the vertical direction of the film blowing die head, but forms an included angle of 45 degrees to 90 degrees with the radial direction of the film blowing die head (equivalent to the radial direction of the central point of the lower end of the upper section of the exhaust pipe), so that the airflow forms a vortex effect of high-speed rotation in the inner space of the circular upper wall plate, and when the airflow is absorbed into the inner space of the circular upper wall plate, can impact and reflect with the inner ring surface of the circular upper wall plate and the upper surface of the circular top cover plate (the circular upper wall plate has the function similar to a echo wall), the vortex effect of the air flow in the inner space of the circular upper wall plate is enhanced, the air pressure at the central part of the vortex is lower, the peripheral part of the vortex has higher air pressure, and the upper end point of the upper section of the exhaust pipe is positioned at the peripheral part of the vortex, thereby being beneficial to pressing high-temperature air flow at the upper part of the film bubble into the exhaust pipe;
thirdly, the vortex effect can be transmitted and extended upwards in the film bubble all the time, so that the topmost air in the film bubble also forms a vortex, the center of the vortex forms low pressure, the topmost air in the film bubble is stirred and sucked away, and the existence of the annular upper wall plate can limit the air flow to form a shortcut near the upper end pipe orifice of the exhaust pipe, so that the air flow is forced to ascend and then descend, the topmost air in the film bubble is prevented from forming a dead angle which can not flow, and the topmost air in the film bubble is prevented from being pumped away and greatly heated;
the cooling air flow of the middle-layer annular air cavity descends, the cooling air flow gradually enters the outer-layer annular air cavity through the small air holes of the middle-layer annular air cavity in the descending process, and the small air holes are more dense as the inner annular wall is closer to the lower end, so that the tendency that the air pressure is lower as the annular air cavity is closer to the downstream of the flow path is favorably counteracted, the air pressure of the outer-layer annular air cavity is more uniformly distributed in the vertical direction, the problem that the air pressure is lower as the annular air cavity is closer to the lower part is avoided, and the pressure distribution of the cooling air flow is more uniform;
and fifthly, the vertical position of the air-permeable small hole positioned at the top is lower than the circular ring-shaped partition plate, so that cooling air flow does not flow into the outer annular air cavity along the radial direction immediately after entering the upper part of the middle-layer annular air cavity from the upper part of the pipe cavity of the inner air pipe through the air inlet gap between the lower sections of the exhaust pipes, but flows downwards for a certain distance and then enters the outer annular air cavity, and the phenomenon that the air pressure of the outer annular air cavity is unevenly distributed in the circumferential direction due to the influence of the exhaust pipes is.
Drawings
Fig. 1 is a schematic view of a cooling structure of a conventional plastic film blowing machine.
Fig. 2 is a schematic diagram of the structural principles and cooling airflow flow paths of an embodiment of the present invention.
Fig. 3 is an enlarged schematic view of a portion of the airflow flow path of fig. 2.
Fig. 4 is an enlarged view of a portion of the structure of fig. 2.
FIG. 5 is a schematic view of the cross-sectional structure K-K in FIG. 4.
Fig. 6 is a schematic view of the H-H cross-sectional structure of fig. 4.
Fig. 7 is a schematic view of the structure of the section J-J in fig. 4.
Fig. 8 is a partial circumferential development of the gas outlet cells on the outer annular wall.
FIG. 9 is a partial circumferential development of the gas permeation apertures in the inner annular wall (the portion near the uppermost portion of the inner annular wall).
Fig. 10 is a schematic perspective view of the upper section of the exhaust duct and the circular upper wall plate.
Fig. 11 is a schematic top view of the structure shown in fig. 10.
FIG. 12 is a schematic view showing the principle that the upper section of the exhaust duct forms airflow vortexes and the vortexes extend upwards,
figure 13 is a schematic illustration of the agitating effect of the gas stream swirl inside the bubble.
Detailed Description
As shown in fig. 2, 4 and 7, the internal cooling structure of the plastic film blowing machine comprises a cylindrical film blowing die head 10, a vertical inner air duct 1 and a vertical outer air duct 2, wherein a blower and an exhaust fan are arranged outside the film blowing die head 10, the walls of the inner air duct 1 and the outer air duct 2 are airtight, the inner air duct 1 and the outer air duct 2 downwards penetrate through the central position of the film blowing die head 10, the central axes of the inner air duct 1 and the outer air duct 2 are overlapped with the central axis m of the film blowing die head 10 (the central axis m of the film blowing die head 10 is represented as a point Z in fig. 5, 6 and 7), the walls of the inner air duct 1 and the outer air duct 2 form a concentric circle relationship in a horizontal projection position, the outer air duct 2 is sleeved outside the inner air duct 1, and the inner air duct 1 upwards extends from the central position of the film blowing die head to the upper part of the film blowing die head 10; an annular outer ring wall 4 is arranged above the film blowing die head 10, and the bottom edge of the outer ring wall 4 is close to the upper surface of the film blowing die head 10; the central axis of the outer annular wall 4 is also overlapped with the central axis of the film blowing die head 10, the circular outer annular wall 4 is provided with a plurality of small air outlet holes 41, and the small air outlet holes 41 are uniformly distributed in the circumferential direction and the vertical direction of the circular outer annular wall 4, as shown in fig. 8; the inner diameter of the circular ring-shaped outer ring wall 4 is larger than the outer diameter of the outer air pipe 2; the top of the circular outer annular wall 4 is connected with a circular top cover plate 7, and the diameter of the circular top cover plate 7 is equal to that of the circular outer annular wall 4; the top end of the cavity 11 of the inner air pipe is open and not closed, the top end of the inner air pipe 1 is lower than the circular top cover plate 7, and a vertical distance is formed between the top end of the inner air pipe and the circular top cover plate;
the outer air pipe 2 also extends upwards from the center of the film blowing die head 10 to the position above the film blowing die head 10, and the vertical position of the top end of the outer air pipe 2 is flush with the vertical position of the top end of the inner air pipe 1;
the inner ring-shaped wall 3 is arranged in the ring-shaped outer ring wall 4, the diameter of the inner ring-shaped wall 3 is larger than that of the outer air pipe and smaller than that of the ring-shaped outer ring wall 4, the top edge of the inner ring-shaped wall 3 is connected with a top cover plate 7, and the bottom edge of the inner ring-shaped wall 3 is close to the upper surface of the film blowing die head 10; the inner annular wall 3 is provided with a plurality of small ventilation holes 31, the small ventilation holes 31 are uniformly distributed in the circumferential direction of the inner annular wall 3, but the small ventilation holes 31 are not uniformly distributed in the vertical direction of the inner annular wall 3, and the smaller the small ventilation holes 31 are, the denser the smaller the holes are, as shown in fig. 9; the vertical position of the air-permeable small hole 31 positioned at the top is lower than the circular ring-shaped clapboard 6, as shown in figure 3; an annular inner-layer annular air cavity 12 is formed between the inner air pipe 1 and the outer air pipe 2; as shown in fig. 2, 4 and 7, an annular middle layer annular air cavity 13 is formed between the outer air pipe 2 and the inner annular wall 3, and an annular outer layer annular air cavity 14 is formed between the inner annular wall 3 and the outer annular wall 4. The blower is communicated with the bottom end of the inner air pipe cavity 11, and the inner air pipe cavity 11 forms an air inlet channel; the exhaust fan is communicated with the bottom end of the inner annular air cavity 12, and the inner annular air cavity 12 is formed into an air outlet channel.
As shown in fig. 2, 4, 5 and 6, the top of the inner annular air cavity 12 is covered with an annular partition plate 6, and the annular partition plate 6 is also lower in vertical position than the top cover plate 7; the central circular hole 60 of the circular ring-shaped clapboard 6 is aligned with the upper port of the inner air duct cavity 11; the circular ring-shaped partition plate 6 is also provided with a plurality of air exhaust holes 61, the air exhaust holes 61 are uniformly distributed along the circumferential direction of the circular ring-shaped partition plate 6, each air exhaust hole 61 is correspondingly connected with one air exhaust pipe 5, and each air exhaust pipe 5 upwards penetrates through the circular top cover plate 7;
as shown in fig. 2, 10 and 11, the exhaust duct 5 is divided into an upper section 51 and a lower section 52, wherein the upper section 51 is located above the top cover plate 7, and the lower section 52 is located between the top cover plate 7 and the annular partition plate 6; an air inlet gap 50 is formed between the lower sections 52 of the exhaust pipes of every two adjacent exhaust pipes; the central part of the circular top cover plate 7 is in a conical tip shape with a large upper part and a small lower part so as to be beneficial to guiding cooling airflow to be converted from vertical direction to horizontal radial direction; the extending direction of the upper section 51 of each section of the exhaust pipe forms oblique intersection with the horizontal plane, and the central axis m of the film blowing die head is represented as a point Z in figure 11; the distance from the upper end of the upper section of the exhaust pipe (shown as the point H in figure 11) to the central axis m of the film blowing die head is greater than the distance from the lower end of the upper section of the exhaust pipe (shown as the point K in figure 11) to the central axis m of the film blowing die head, namely, in figure 11, the ZH distance is greater than the ZK distance; on the horizontal projection plane, the extending direction of each exhaust duct upper section 51 and the radial direction of the central point of the lower end of the exhaust duct upper section form an included angle of 60 °, for example, in fig. 11, the extending direction of one section of each exhaust duct upper section 51 is KH, the central point of the lower end of the exhaust duct upper section is K point, and the radial direction KM of the K point is 60 ° in fig. 11.
As shown in fig. 2, 10 and 11, a circular upper wall plate 9 is further disposed above the circular top cover plate 7, a central axis of the circular upper wall plate 9 overlaps a central axis m of the film blowing die head, a height of the circular upper wall plate 9 is greater than a height of the upper section 51 of the exhaust duct, a radius of the circular upper wall plate 9 is greater than an eccentric distance ZH of an upper end (indicated by a point H in fig. 11) of the upper section 51 of the exhaust duct, that is, the circular upper wall plate 9 surrounds all the upper sections 51 of the exhaust duct.
In the above embodiment, on the horizontal projection plane, the extending direction of the upper section 51 of each exhaust duct and the radial direction of the central point of the lower end of the upper section of the exhaust duct may also form an included angle of 45 degrees, or an included angle of 90 degrees; that is, in fig. 11, angle KMH may be 45 °, or 75 °, or 90 °.
The working process and principle of the above embodiment are as follows:
cooling airflow is blown into the pipe cavity 11 of the inner air pipe by a blower, flows upwards from the pipe cavity 11 of the inner air pipe, reaches the upper part of the pipe cavity of the inner air pipe, then passes through an air inlet gap 50 between the lower sections 52 of every two adjacent exhaust pipes, enters the annular air cavity 13 of the middle layer, then flows downwards from the annular air cavity 13 of the middle layer, gradually enters the annular air cavity 14 of the outer layer through the small air holes 31 of the inner annular wall on the way downwards, and finally is blown out from the small air outlet holes 41 of the annular air cavity 14 of the outer layer, so that the inner surface of the bubble is cooled; after cooling the bubble by the airflow, the temperature gradually rises, then the high-temperature airflow goes upward to reach the top space of the bubble 8, and is sucked into the inner annular air cavity 12 through each exhaust pipe 5, flows downward, and is finally pumped out from the lower end of the inner annular air cavity 12 and is pumped out by the exhaust fan, and the airflow flowing process is shown by arrows in fig. 2 and 3.
In addition, the upper section 51 of each exhaust pipe forms a rotational symmetry relation with the central axis m of the film blowing die head, and the extending direction of the upper section of each exhaust pipe forms an included angle with the radial direction of the central point of the lower end of the upper section of the exhaust pipe, so that the direction of the air flow sucked into the exhaust pipe 5 on the upper part of the film bubble does not form an included angle of 45-90 degrees with the radial direction of the film blowing die head along the vertical direction or the radial direction of the film blowing die head, so that the air flow forms a vortex effect of high-speed rotation in the inner space of the circular upper wall plate, and when the air flow is absorbed into the inner space of the circular upper wall plate 9, the air flow collides and reflects with the inner ring surface of the circular upper wall plate and the upper surface of the circular top cover plate 7 (the circular upper wall plate has the function similar to an echo wall, as shown by arrows in fig. 2 and fig. 3), the vortex effect of, the air pressure at the peripheral part of the vortex is higher, and the upper end point of the upper section 51 of the exhaust pipe is positioned at the peripheral part of the vortex, so that the high-temperature air flow at the upper part of the film bubble is favorably pressed into the exhaust pipe; in addition, the vortex effect can be transmitted and extended upwards inside the bubble, so that the air at the uppermost part inside the bubble 8 also forms a vortex, as shown in fig. 12 and 13, the center of the vortex forms low pressure, which is beneficial to stirring and sucking away the uppermost air inside the bubble, and avoids the uppermost air inside the bubble 8 from forming a dead angle which can not flow, thereby avoiding the uppermost air inside the bubble from being difficult to be pumped away and greatly increasing the temperature.
Claims (3)
1. An inner cooling structure of a plastic film blowing machine comprises a cylindrical film blowing die head, a vertical inner air pipe and a vertical outer air pipe, wherein a blower and an exhaust fan are arranged outside the film blowing die head;
an annular outer ring wall is arranged above the film blowing die head, the bottom edge of the outer ring wall is close to the upper surface of the film blowing die head, and the central axis of the outer ring wall is also overlapped with the central axis of the film blowing die head; the annular outer ring wall is provided with a plurality of small air outlet holes which are uniformly distributed in the circumferential direction of the annular outer ring wall, and the inner diameter of the annular outer ring wall is larger than the outer diameter of the outer air pipe; the top of the circular outer ring wall is connected with a circular top cover plate, and the diameter of the circular top cover plate is equal to that of the circular outer ring wall; the method is characterized in that: the top end of the cavity of the inner air pipe is open, the top end of the inner air pipe is lower than the circular top cover plate, and a vertical distance is formed between the top end of the inner air pipe and the circular top cover plate; the outer air pipe also extends upwards to the position above the film blowing die head from the center of the film blowing die head, and the vertical position of the top end of the outer air pipe is flush with the vertical position of the top end of the inner air pipe; the inner side of the annular outer ring wall is provided with an annular inner ring wall, the diameter of the inner ring wall is larger than that of the outer air pipe and smaller than that of the annular outer ring wall, the top edge of the inner ring wall is connected with a top cover plate, and the bottom edge of the inner ring wall is close to the upper surface of the film blowing die head; the inner annular wall is provided with a plurality of small air holes, the small air holes are uniformly distributed in the circumferential direction of the inner annular wall, but the small air holes are not uniformly distributed in the vertical direction of the inner annular wall, and the smaller the position of the small air holes is, the denser the position of the small air holes is; an annular inner layer annular air cavity is formed between the inner air pipe and the outer air pipe; a circular middle layer annular air cavity is formed between the outer air pipe and the inner annular wall, and a circular outer layer annular air cavity is formed between the inner annular wall and the outer annular wall; the blower is communicated with the bottom end of the pipe cavity of the inner air pipe, and the pipe cavity of the inner air pipe forms an air inlet channel; the exhaust fan is communicated with the bottom end of the inner-layer annular air cavity, and the inner-layer annular air cavity is formed into an air outlet channel; the top of the inner layer annular air cavity is covered with an annular clapboard, and the vertical position of the annular clapboard is lower than that of the top cover plate; the central circular hole of the circular ring-shaped partition plate is aligned with the upper port of the inner air pipe; the vertical position of the air-permeable small hole on the uppermost part of the inner ring wall is lower than the annular clapboard; the circular ring-shaped partition plate is also provided with a plurality of air exhaust holes, the air exhaust holes are uniformly distributed along the circumferential direction of the circular ring-shaped partition plate, each air exhaust hole is correspondingly connected with one air exhaust pipe, and each air exhaust pipe upwards penetrates through the circular top cover plate; the exhaust pipe is divided into an upper exhaust pipe section and a lower exhaust pipe section, wherein the upper exhaust pipe section is positioned above the top cover plate, and the lower exhaust pipe section is positioned between the top cover plate and the annular partition plate; an air inlet gap is formed between the lower sections of the exhaust pipes of every two adjacent exhaust pipes; the upper sections of the exhaust pipes form a rotational symmetry relation with the central axis of the film blowing die head; the extending direction of the upper section of each section of exhaust pipe forms oblique intersection with the horizontal plane, and the distance from the upper end of the upper section of the exhaust pipe to the central axis of the film blowing die head is greater than the distance from the lower end of the upper section of the exhaust pipe to the central axis of the film blowing die head; on the horizontal projection plane, the extending direction of the upper section of each exhaust duct and the radial direction of the central point of the lower end of the upper section of the exhaust duct form an included angle of 45-90 degrees; the upper part of the circular top cover plate is also provided with a circular upper wall plate, the central axis of the circular upper wall plate is overlapped with the central axis of the film blowing die head, the height of the circular upper wall plate is larger than that of the upper section of the exhaust pipe, and the radius of the circular upper wall plate is larger than the eccentric distance of the upper end of the upper section of the exhaust pipe.
2. The internal cooling structure of the plastic film blowing machine according to claim 1, characterized in that: the extending direction of the upper section of each exhaust pipe and the radial direction of the central point of the lower end of the upper section of each exhaust pipe form an included angle of 60 degrees to 75 degrees.
3. The internal cooling structure of the plastic film blowing machine according to claim 1, characterized in that: the central part of the circular top cover plate is in a conical tip shape with a large upper part and a small lower part.
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| CN201810363480.6A CN109605720B (en) | 2018-04-21 | 2018-04-21 | Inner cooling structure of plastic film blowing machine |
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| CN111929026B (en) * | 2020-09-29 | 2020-12-15 | 中国空气动力研究与发展中心低速空气动力研究所 | Low-frequency pressure pulsation suppression method for wind tunnel 3/4 opening test section |
| CN116572518B (en) * | 2023-07-13 | 2023-09-19 | 山东方大新材料科技有限公司 | Film blowing mechanism of film blowing machine |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3714309A (en) * | 1970-08-11 | 1973-01-30 | Gen Engineering Co | Manufacture of plastic film |
| US4115048A (en) * | 1976-12-27 | 1978-09-19 | Union Carbide Corporation | Apparatus for internally cooling a plastic tubular film bubble |
| CN203527730U (en) * | 2013-10-10 | 2014-04-09 | 中山市和美塑胶材料有限公司 | Circulating cooling device in bubble of film blowing machine |
| CN107053648A (en) * | 2017-05-26 | 2017-08-18 | 广东金明精机股份有限公司 | Upward type internal cooling structure for multilayer co-extrusion film blowing machine |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54158464A (en) * | 1978-06-03 | 1979-12-14 | Modan Machinery | Equipment for cooling inner face of plastic film |
| JPS58179620A (en) * | 1982-04-14 | 1983-10-20 | Idemitsu Petrochem Co Ltd | Cooler for blown-film extrusion |
-
2018
- 2018-04-21 CN CN201810363480.6A patent/CN109605720B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3714309A (en) * | 1970-08-11 | 1973-01-30 | Gen Engineering Co | Manufacture of plastic film |
| US4115048A (en) * | 1976-12-27 | 1978-09-19 | Union Carbide Corporation | Apparatus for internally cooling a plastic tubular film bubble |
| CN203527730U (en) * | 2013-10-10 | 2014-04-09 | 中山市和美塑胶材料有限公司 | Circulating cooling device in bubble of film blowing machine |
| CN107053648A (en) * | 2017-05-26 | 2017-08-18 | 广东金明精机股份有限公司 | Upward type internal cooling structure for multilayer co-extrusion film blowing machine |
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