CN214447931U - Cooling device after calendering molding in equipment for producing PVC sheets - Google Patents

Abstract

A cooling device for PVC sheet material after extrusion molding is capable of making the thickness of hard PVC sheet material uniform, further improving the longitudinal and transverse shrinkage rate, widening the subsequent processing conditions, facilitating demoulding of the packaging material by the user when the cooling device is used for plastic uptake processing, and improving the smoothness and transparency of the sheet material. A rigidity improving station capable of improving rigidity of a PVC sheet is arranged between an initial cooling area and a room temperature insulation area after a leading-away roller, the rigidity improving station is composed of a water tank, a rubber roller and a steel roller, the rubber roller and the water tank are sequentially horizontally arranged from top to bottom in the vertical direction, the bottom surface of the rubber roller is immersed in the water tank, and the PVC sheet penetrates through the steel roller and the rubber roller which are pressed together and rotate in opposite directions. The PVC sheet passing through the rigidity improving section is stimulated by the rapid cooling of ice water, so that the plastic resilience characteristic of the PVC sheet is restricted, and the transverse shrinkage rate of the PVC sheet is effectively improved.

Description

Cooling device after calendering molding in equipment for producing PVC sheets

Technical Field

The utility model relates to a production facility of stereoplasm PVC sheet, in particular to be arranged in this production facility to carry out the device that cools down to the PVC sheet after the calendering shaping.

Background

PVC (the name in the literature: polyvinyl chloride) is easy to process and can be processed by means of moulding, lamination, injection moulding, extrusion, calendering, blow moulding hollowing, etc. PVC mainly used production plastics soft goods such as synthetic leather, film, electric wire sheath, water supply pipe, domestic pipeline, house wallboard, commercial machine casing, electronic product package, medical instrument, food package also can produce plastics hard goods such as panel, door and window and valve.

A transparent PVC sheet is prepared from PVC through adding impact modifier and stabilizer, mixing, plasticizing and calendering. Then the product can be made into thin-wall transparent container by thermoforming, and can also be used for vacuum plastic packaging such as moon cake packaging box, etc., which is an excellent packaging material and decorative material.

In the prior art, calendering equipment with less than four rollers is mostly adopted in assembly line equipment for producing hard PVC sheets, and due to the limitation of each process condition equipment of a subsequent stretching process, a cooling process and a heat preservation process, the thickness of the PVC sheets produced by the assembly line cannot be controlled in a thinner range.

In addition, in order to ensure that the PVC sheet has a set longitudinal shrinkage rate after calendering, the prior art has to increase the conveying speed of the PVC sheet in the room temperature holding section (i.e., ensure a certain longitudinal tensile force) and the length of the room temperature holding section.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is to provide a heat sink after the calendering molding in production PVC sheet equipment, it can make stereoplasm PVC sheet thickness even, further improve its indulge, horizontal shrinkage factor, make follow-up processing condition widen and the user is used for the easier drawing of patterns of blister processing of packaging material, still can improve the smooth finish and the transparency of sheet simultaneously.

In order to solve the technical problem, the utility model discloses a technical scheme be:

the utility model discloses a heat sink after production PVC sheet equipment middling pressure roll forming, including leading from the initial stage cooling area and the room temperature heat preservation district after the roller, its characterized in that: the rigidity improvement station capable of improving the rigidity of the PVC sheet is arranged between the initial cooling area and the room temperature insulation area, the rigidity improvement station consists of a water tank, a rubber roller and a steel roller, the rubber roller and the water tank are sequentially arranged horizontally from top to bottom in the vertical direction, the bottom surface of the rubber roller is immersed in the water tank, and the PVC sheet penetrates through the steel roller and the rubber roller which are pressed together and rotate in opposite directions.

Circulating ice water with the temperature of 13-17 ℃ is filled in the water tank.

The steel roller can move up and down in the vertical direction, and two ends of the steel roller are respectively connected with a piston rod of a vertically arranged cylinder.

The diameter of the steel roller is 300-350 mm; the diameter of the rubber roller is 400-600 mm.

The water tank is internally provided with a temperature sensor which is electrically connected with a main control circuit of the assembly line equipment, and the main control circuit opens or closes an ice water supply valve arranged on the water tank and a water outlet valve for discharging the heated ice water in the tank in real time according to a set water temperature range.

The utility model discloses a six-roller calender mangles the PVC sizing material into the sheet that the thickness is thinner, the chill roll in the initial section cooling zone after adopting the frozen water that circulates to the calender cools down again, make this chill roll surface temperature uniformity everywhere unanimous, when by calender discharge gate output and for the PVC sheet of higher temperature state behind these chill rolls, can make the PVC sheet after taking shape more even at the ascending temperature of width direction to make the PVC sheet obtain improving at width direction's thickness uniformity. The PVC sheet passing through the initial cooling area and the rigidity improving section is stimulated to be rapidly cooled by arranging the ice water cooling on the cooling roller in the initial cooling area and arranging the rigidity improving section which is subjected to ice water cooling treatment again in the subsequent process, so that the plastic rebound property of the PVC sheet is restricted, and the transverse shrinkage rate of the PVC sheet is effectively improved.

Drawings

Fig. 1 is a schematic view of the PVC sheet flow line production equipment of the present invention.

Fig. 2 is an enlarged schematic view of region a in fig. 1.

Fig. 3 is an enlarged view of region B in fig. 1.

Fig. 4 is an enlarged view of region C in fig. 1.

Fig. 5 is an enlarged view of region D in fig. 1.

The reference numbers are as follows:

the device comprises a PVC sheet 1, a calender 2, a first roller 21, a second roller 22, a third roller 23, a fourth roller 24, a fifth roller 25, a sixth roller 26, a leading-out roller 3, a primary cooling area 4, two front stripping rollers 41, five rear stripping rollers 42, a rigidity improving section 5, a rubber roller 51, a steel roller 52, a water tank 53, a room temperature insulation area 6, a cooling roller 61, an edge material online crushing and recovering device 7, a cutting device 71, an edge material guide ring 72, an edge material recovery air pipe 73, an edge material recovery hopper 74, a sheet tension adjusting device 8, a first guide roller 81, a tensioning support roller 82, a tensioning adjusting swing roller 83, a second guide roller 84, a frame plate 85, a swing plate 86, an angle shifter 87, a sheet finished product winding device 9, an assembly line production equipment 100, a high-speed pan 101, a cooling pan 102, an extruder 103, an open mill 104 and a feeder 105.

Detailed Description

As shown in fig. 1-5, the assembly line equipment for producing environment-friendly ultra-thin hard PVC sheets (hereinafter also referred to as sheets) of the present invention comprises, from front to back, a rack-mounted: the production line comprises process equipment or process sections such as a high-speed pan 101, a cooling pan 102, an extruder 103, an open mill 104, a feeder 105, a calender 2, a leading-off part, a primary cooling zone 4, a rigidity improving zone 5, a room temperature insulation zone 6, an online rim charge crushing and recovering device 7, a sheet tension adjusting device 8, a finished sheet winding device 9 and a PLC automatic control and monitoring system (contained in a main control circuit of the production line equipment), and the like (note: for the convenience of drawing, the components of the process equipment or the process sections are not shown in a frame for supporting the components).

The utility model discloses an assembly line production facility 100 is through improving many times, and the thickness scope control of the PVC sheet 1 of production is at 0.07mm-1.20mm, and the factor that influences the thickness of PVC sheet 1 and thickness homogeneity has clearance between 2 each calendering rollers of calender, the temperature of calendering roller, the temperature of peel roller and the speed difference of each roller and the prescription of major ingredient and auxiliary material etc..

1. The high-speed pan 101, also known as a high-speed mixer, is provided with stirring blades and a deflector.

As shown in fig. 1 and 2, the main material and the auxiliary material (the main material and the auxiliary material are fed into the high-speed pan 101 by a pneumatic negative pressure conveying device) are mixed by the paddle at a high speed, and during mixing, the main material and the auxiliary material are fully collided, contacted and rubbed to ensure that the molecules of the main material and the auxiliary material are fully fused and adsorbed with each other, so that the particles of each component are distributed to the maximum extent, and are prepared into a powdery mixture which is uniform, loose, non-caking and easy to flow, thereby obtaining the material with a certain temperature and a preplasticizing degree.

Taking the mixture out of the pot after the stirring time is about 420 seconds, and controlling the temperature to be 105-120 ℃. If the temperature is too high or too long, the main material is easily decomposed, and if the temperature is too low, the material is easily generated (also called immature), the material is not easily plasticized during production, and finally the performance (such as rigidity, strength and shrinkage rate) of the finished PVC sheet 1 is reduced.

For the natural color transparent PVC sheet 1, in order to ensure the transparency of the product and reduce the number of crystal points and impurities, the granular main material and auxiliary material must be sieved, usually 60-mesh sieve, and the liquid auxiliary agent is sieved by 120-mesh sieve.

2. As shown in fig. 1 and 2, a cooling pan 102, also called a cooling mixer, injects a material mixed by a high-speed machine into the cooling pan 102 to cool, and the cooling pan 102 is a water cooling device composed of a pan wall and an inner container. The purpose is as follows: the material is cooled to the normal processing temperature of 60 +/-2 ℃ to avoid the material being heated and agglomerated. The cold mixing and discharging are carried out at the temperature, so that the mixture is prevented from absorbing moisture in the air and becoming damp and yellow due to overhigh temperature in the placing process. The mixed dry mixture is preferably stored at room temperature for more than 8 hours, which is beneficial to further curing the materials, eliminating static electricity generated in the mixing process, improving the fluidity of the dry mixture and being beneficial to the implementation of the extrusion process.

In order to improve the utilization rate of the PVC sheet 1, the scrap cut out in the subsequent manufacturing process is fed into the cooling pan 102 by an amount proportional to the amount of the new material by the scrap collecting and feeding device.

3. The extruder 103, which is a conventionally used apparatus, is shown in fig. 1 and 2, and adjusts the flow rate of the extrusion amount according to the calendering line speed, the extrusion plasticizing temperature is determined according to the material formula and the thickness of the sheet material, and the discharge temperature is generally controlled at 140 ℃ to 160 ℃.

4. Open mill 104: as shown in fig. 1 and 2, the extruder consists of two large-diameter rotating rollers which are arranged up and down after the extruder 103, hot oil is introduced into the two rotating rollers for circulating heat preservation, and the oil temperature is 156-162 ℃. The function is as follows: in order to enable the rubber compound (the rubber material extruded by the extruder 103) to be processed smoothly and to be operated conveniently and to obtain a smooth semi-finished product without bubbles and pimples, the rubber material extruded by the extruder 103 is turned and preheated on the open mill 104 so as to achieve certain and uniform thermal plasticity. Generally, the compound just extruded from the extruder 103 is relatively hard (i.e., has poor plasticity), so that the compound extruded from the extruder 103 is introduced between two rotating rollers, and the plasticity of the compound can be effectively improved through multiple times of extrusion and kneading.

The cooking process performed by the open mill 104 also has the following benefits:

1) supplementary mixing is carried out, so that the auxiliary agents in various auxiliary materials are further uniformly dispersed in the rubber material;

2) the sizing material is softened, and the molding operation is convenient;

3) improves the fluidity and self-viscosity of the rubber material, and is beneficial to the forming process and the operating process.

The utility model discloses a change the roller in mill 104, long X diameter is 1500mm X560, for making the sizing material reach good hot plasticity, the high roll temperature (the temperature is at 150 ℃ -160 ℃), big roll spacing (the roll spacing is at 4-8mm), cross the roller 6-7 times for the sizing material obtains better hot plasticity.

The turnover is limited and turned over by the turnover gyros arranged on two sides of the top of the upper rotating roller of the open mill 104, the return materials are mixed in a coal bed for many times between the two turnover gyros, the turnover gyros have a limiting effect, and the turnover has the main function of continuously turning over accumulated materials and increasing the fluidity, so that the temperature plasticization is more uniform.

5. The feeder 105: as shown in fig. 1 and 3, after the open mill 104, the sizing material fed from the open mill 104 is continuously fed into the calender 2 at a set thickness and width, and the feeder 105 is arranged obliquely upward at an angle of about 60 degrees, and has a lower end connected to the sizing material outlet of the open mill 104 and an upper end connected to a set of rolls at the highest position in the calender 2. The length of the feeder 105 is around 3 meters.

6. Calender 2

As shown in fig. 1 and 3, the utility model discloses a calender 2 comprises six calendering rollers, and the mode of laying of six calendering rollers from top to bottom is laid the structure by positive "Z" type and is laid the combination that the structure was laid to positive "I" type. The utility model discloses a six calendering rollers have obvious help to improving the off-the-shelf glossiness of sheet, reducing flow line and bubble.

The positive Z-shaped layout structure: the roller device is composed of a first roller 21 to a fourth roller 24, wherein the first roller 21 and the second roller 22 are arranged in a same horizontal plane, the third roller 23 and the fourth roller 24 are positioned below the first roller 21 and the second roller 22, the third roller 23 and the fourth roller 24 are also arranged in a same horizontal plane, and the second roller 22 and the third roller 23 are arranged in a same vertical plane; the first roller 21 and the second roller 22 rotate in opposition, the second roller 22 and the third roller 23 rotate in opposition, and the third roller 23 and the fourth roller 24 rotate in opposition.

The positive I-shaped layout structure: the fourth roller 24, the fifth roller 25 and the sixth roller 26 are arranged in the same vertical plane; the fourth roller 24 and the fifth roller 25 rotate in opposite directions, and the fifth roller 25 and the sixth roller 26 rotate in opposite directions.

The outer diameters of the first roller 24 to the fourth roller 24 are 450mm, the outer diameters of the fifth roller 25 and the sixth roller 26 are 500mm, the six calendering rollers are circularly heated by adopting heat conduction oil (namely heat conduction oil circulating channels are arranged in the calendering rollers), the temperature is about 200 ℃, the roller speed is 35 m/min, and the length of each calendering roller is 1300 mm.

The rolling process comprises the following steps: thermoplastic rubber conveyed by the feeding machine 105 passes through a calendering roller gap rotating oppositely, and plastic flow deformation is generated on the rubber by using the rotating friction force and extrusion force between two adjacent rollers in the calender 2, the thickness of the section of the rubber is reduced during calendering, and simultaneously, the section width and the length of the rubber are increased, and finally, the PVC sheet 1 with a certain section size specification and a specified section geometry is manufactured.

The temperature of the PVC sheet 1 output after being rolled and formed by the calender 2 is 150-170 ℃.

7. The leading-away part is a leading-away roller 3, as shown in fig. 1 and 3, which is the roller closest to the calender 2 and is a conventional part for introducing the PVC sheet material rolled into the sheet material and then performing the heat preservation and temperature reduction processes. The take-off roll 3 is typically heated and surface treated to prevent adhesion of the PVC sheet 1. The linear speed of the take-off roll 3 is generally higher than the linear speed of the calendering rolls of the calender 2, which, on the one hand, leave the PVC sheet 1 from the calender 2 and, on the other hand, exert a certain stretching action on the PVC sheet 1.

8. The primary cooling zone 4, as shown in fig. 1, 3 and 4, is intended to reduce the deformation caused by shrinkage when the PVC sheet 1 is rolled, and to cool the PVC sheet 1 in a hotter state before rolling so as to reduce the shrinkage deformation of the sheet.

The initial cooling area 4 is arranged by seven stripping rollers in turn along the conveying direction of the calendered and formed PVC sheet 1, a water circulation channel for introducing cooling water or heat preservation water is arranged in the seven stripping rollers, the PVC sheet 1 moves from the stripping rollers of the initial cooling area 4 to the discharging direction in a threading method transmission mode under the traction of a finished product winding device, and the front side and the back side of the sheet are alternately contacted with the surfaces of the stripping rollers in the advancing process of the PVC sheet 1 by the threading method transmission.

The first two stripping rollers 41 in the seven stripping rollers adopt ice water with the temperature of 13-17 ℃ for cooling in a circulating manner (the preferred inlet and outlet ends of the ice water are respectively arranged at the two ends of the stripping rollers, so that the cooling effect is better); the last five stripping rollers 42 adopt warm water with the temperature of 75-90 ℃ for circular cooling and heat preservation.

Note: cooling is required to be proper, and if the cooling is insufficient, the cooled film is easy to become sticky and crepe, and the shrinkage rate after winding is also relatively large; if the cooling is too high, the roller temperature will be too low and water drops will form, which will also affect the product quality.

Every two adjacent stripping rollers in the seven stripping rollers rotate in the same direction, and the roller speed of the seven stripping rollers is the same, wherein the specific speed is determined according to the thickness requirement of the produced sheet.

In the initial cooling area 4, two former peel rolls 41 (hereinafter referred to as a roller a and a roller B) adopt ice water cooling to be the utility model discloses a big improvement, its beneficial effect that can produce is: the surface temperature of the stripping roller can be uniformly distributed along the axial direction, so that the thickness of the PVC sheet material is uniform, in addition, the adoption of ice water with moderate low temperature for cooling is favorable for improving the rigidity of the PVC sheet material 1, and the PVC sheet material formed after calendering is prevented from falling and deforming due to the action of gravity in the subsequent cooling process.

In the prior art, each stripping roller in the initial cooling zone 4 adopts heat conduction oil for cooling or heat preservation, and because the viscosity of the heat conduction oil is far greater than that of water, the heat conduction oil is adopted as a circulating cooling medium, the flow rate is slow, and the cooling effect is poor. The reason why the temperature of the surface of the peeling roller is not uniform is as follows:

1) the heat conducting oil entering the stripping roller continuously absorbs heat on the stripping roller in the flowing process, so that the temperature difference between the heat conducting oil at the inlet of the stripping roller and the heat conducting oil at the outlet of the stripping roller is large (namely the temperature of the roller surface at the oil inlet end of the stripping roller is inevitably lower than that of the roller surface at the oil outlet end), and the temperature of the surface of the stripping roller in the flowing direction of the heat conducting oil is easily uneven (namely when the cooling degrees of the sheets at the oil inlet end and the oil outlet end of the stripping roller are different, the shrinkage rates of the sheets at the two ends are different).

2) The stripping roller is arranged in a suspension manner, and the temperature of two end parts of the stripping roller is lower than that of the central part generally because the end parts are connected with the rotating part and the supporting part arranged on the frame, so that the end parts of the stripping roller continuously transfer heat to the frame to dissipate heat, and the surface temperature of the stripping roller is uneven.

And the utility model discloses a A roller and B roller adopt the frozen water cooling can overcome the defect that adopts the conduction oil cooling to lead to among the prior art, reason as follows: the flow rate of water is easy to control firstly, and the temperature of the water is easy to control secondly, so that the heat exchange efficiency between ice water for cooling and the roll surfaces of the roller A and the roller B is greatly increased, and the uniformity and consistency of the temperature of the roll surfaces of the roller A and the roller B are effectively improved.

The forming mechanism and the relation between the surface temperature of a calendering roller and the quality of the PVC sheet 1 are analyzed:

1) during calendering, the resistance of the rubber compound along the axial direction of the calendering roll (the width direction of the calendered rubber compound) is large (the friction force between the rubber compound and the calendering roll is larger than the resistance extruded in the length direction), and the rubber compound is difficult to flow and deform, so that the width change of the rubber compound during calendering is small. The feed width of the calendering should be as close as possible to the calendering width. The feeding width of the feeding machine 105 of the utility model is about 100mm wide, and when the feeding machine 105 feeds, the feeding head swings left and right in the width direction to feed.

The reduction of the thickness of the cross section of the PVC rubber material is accompanied by the increase of the width of the cross section and the length of the rubber material during the calendering. The sizing material is subjected to a great stretching effect when passing through the gap between the two calendering rollers, so that the molecular chain is partially straightened, and recoverable elastic deformation is generated. The flow rate of the sizing material is high during rolling, the partially straightened molecular chain cannot be relaxed and retracted when leaving the gap, namely, the elastic deformation is brought out of the gap, after rolling, the flow is suddenly stopped, and the partially straightened molecular chain is firstly curled and retracted quickly and mostly. When the rolled product is parked, the rolled product is slowly further retracted, so that the rolled product generates longitudinal shrinkage deformation, the length is reduced, the section thickness is increased, the precision of the product thickness is influenced, and the surface smoothness is also influenced. The greater the degree of elastic deformation of the compound, the greater the rate of shrinkage deformation of the semi-finished product or finished product.

Because the sizing material is subjected to great shearing and stretching force along the rolling direction, polymer macromolecules can be oriented and arranged along the rolling direction of the film (including a sheet), so that the film has anisotropy on physical and mechanical properties, namely, the film has great tensile strength along the rolling direction, small elongation and great shrinkage, and the film has small tensile strength along the direction vertical to the rolling direction, great elongation and small shrinkage, and the phenomenon of difference of longitudinal and transverse directional performance is generally called rolling effect or orientation effect in rolling forming. Because the influence of calendering effect, the PVC film after the shaping, when being heated under free state, because of different orientation makes the shrink of PVC film longitudinal length, the transverse width then expands, the utility model discloses the PVC film longitudinal length shrinkage factor of equipment preparation can be at 85% -95% (big than prior art), and the transverse width then expansion ratio is steerable between 0-3% (less than prior art).

The degree of calendering or orientation effect increases with increasing calendering speed, speed ratio of the rolls, amount of glue stored in the roll gap and apparent viscosity of the material, and decreases with increasing roll temperature, roll gap and calendering time.

2) One of the most prominent problems in the quality of calendered products is generally the transverse thickness non-uniformity, generally greater at the middle and ends, and thinner at the sides of the near-middle zone, commonly known as the "three high two low" phenomenon. This phenomenon is mainly caused by elastic bending deformation of the reduction rolls and a low temperature at both ends of the reduction rolls.

Elastic bending deformation of the calender roll: is the separating force (caused by transverse pressure) of the rubber compound on the roller of the calendering roller during calendering. This bending deformation gradually decreases from the center of the roll axis where the deformation is largest toward both ends, with the result that the cross-sectional thickness of the rolled product becomes gradually thinner from the center of the roll axis to the edges. When the rubber sheet is reeled, the tension in the middle of the rubber sheet is higher than that on two sides, so that the phenomenon of unevenness appears after unreeling. The greater the aspect ratio (length to diameter) of the roll, the greater the effect of this elastic deformation.

During calendering, the temperature of the end of the roller of the calender 2 is usually lower than that of the central part because the lubricating oil of the bearing takes away part of the heat, and on the other hand, the roller continuously transfers heat to the frame to dissipate the heat. The roll surface temperature is not uniform, although the section thickness of the rolled product becomes thinner gradually from the center of the roll axis to the edge, the degree of the calendering effect or the orientation effect is reduced along with the increase of the roll temperature, therefore, when the temperature of the end part of the roll is lower than that of the central part, the thickness of the two sides of the product is larger than that of the middle part, and the section of the rolled product is not uniformly expanded.

In the prior art, methods for overcoming the temperature difference of the axial surface of the roller can adopt infrared rays or other methods for compensating heating at a lower temperature part or adopt air pipes for cooling in the areas close to the middle of two sides of the roller, but the inherent quality of products can be uneven.

And the utility model discloses a cooling is carried out to the peel roll by 2 discharge gates departments of calender to the faster frozen water of circulation speed, can reduce the difference in temperature between peel roll central part and the roller both ends, make PVC sheet 1 after 2 calendering molding of calender that constitute through six calendering rolls get into the lower and even cooling treatment station of temperature very fast, thereby, the degree that makes the calendering effect or the directional effect of the PVC sheet 1 that gets into initial cooling zone 4 is in stable and lower state, and have better rigidity and in order to prevent this PVC sheet 1 receive the action of gravity and tenesmus in the technology processing procedure after.

Namely the utility model discloses a calender 2 of six roller structures makes the PVC sheet 1 of setting for thickness with the sizing material, and the A roller and the B roller ice water cooling of rethread initial stage cooling zone 4 improve the thickness homogeneity and the rigidity of PVC sheet 1, can effectively shorten the length of initial stage cooling zone 4 and PVC sheet 1 at the cooling and the heat preservation time of this section.

9. Rigidity-improving section 5

As shown in fig. 1 and 4, another improvement of the present invention is: before entering the room temperature insulation zone 6 after the initial cooling zone 4, a rigidity improving station capable of further improving the rigidity of the PVC sheet 1 is arranged, the rigidity improving station is composed of a water tank 53, a rubber roller 51 and a steel roller 52, the rubber roller 51 and the water tank 53 are sequentially and horizontally arranged from top to bottom in the vertical direction, the bottom surface of the rubber roller 51 is immersed in the water tank 53, and the PVC sheet 1 penetrates through the steel roller 52 and the rubber roller 51 which are pressed together and rotate oppositely.

Circulating ice water with the temperature of 13-17 ℃ is filled in the water tank 53, the steel roller 52 can move up and down in the vertical direction, and two ends of the steel roller 52 are respectively connected with a piston rod of a vertically arranged air cylinder.

The diameter of the steel roller 52 is 300-350 mm; the diameter of the rubber roller 51 is 400-600mm, preferably the diameter of the steel roller 52 is 280mm, the diameter of the rubber roller 51 is 380mm, and the diameter of the steel roller 52 is smaller than that of the rubber roller 51, so that ice water droplets accumulated on the PVC sheet 1 can be effectively removed. The steel roller 52 can rapidly conduct away heat on the PVC sheet 1, and the rigid-flexible combination of the steel roller 52 and the rubber roller 51 can enable the top surface and the bottom surface of the PVC sheet 1 passing through the steel roller 52 and the rubber roller 51 to be tangent better (namely, in the tangent direction of the sheet and the roller, each point on the sheet can be contacted with the corresponding roller, and the defect of incomplete contact caused by rigid combination of the two steel rollers 52 cannot occur).

When the PVC sheet material cold-rolling device works, the steel roller 52 falls down and is pressed against the upper surface of the PVC sheet material 1 penetrating between the steel roller 52 and the rubber roller 51, the steel roller 52 and the rubber roller 51 rotate oppositely, ice water in the water tank 53 is carried to the upper part by the rotating rubber roller 51 from the lower part along with the rotation of the rubber roller 51, the PVC sheet material 1 penetrating between the rubber roller 51 and the steel roller 52 is cooled again, a plurality of water drops are accumulated on the bottom surface of the PVC sheet material 1 during cooling, and under the condition of the same rotating angle, the stroke of the steel roller 52 rolled on the upper surface of the PVC sheet material 1 is shorter than that of the rubber roller 51 due to the fact that the diameter of the steel roller 52 is smaller than that of the rubber roller 51, and the steel roller 52 is tangent to the rubber roller 51, so that the structure can effectively extrude the water drops accumulated on the bottom surface of the PVC sheet material, and the water drops are completely filtered. The structure can improve the physical property of the finished product and further improve the rigidity of the PVC sheet 1; the longitudinal shrinkage and the transverse shrinkage of the sheet are improved, so that the subsequent processing conditions are widened, and the demoulding is easier when the sheet is used for the blister processing of packaging materials by users; meanwhile, the smoothness and the transparency of the sheet can be improved.

During operation, the steel roller 52 falls down to abut against the upper surface of the PVC sheet 1 passing through the space between the steel roller 52 and the rubber roller 51, the steel roller 52 and the rubber roller 51 rotate oppositely, ice water in the water tank 53 is carried by the rotating rubber roller 51 from bottom to top along with the rotation of the rubber roller 51, the PVC sheet 1 passing through the space between the rubber roller 51 and the steel roller 52 is cooled again, and meanwhile, water drops on the sheet passing through the steel roller 52 and the rubber roller 51 are also completely ground and filtered due to the tangency between the steel roller 52 and the rubber roller 51. The structure can improve the physical property of the finished product and further improve the rigidity of the PVC sheet 1; the longitudinal shrinkage and the transverse shrinkage of the sheet are improved, so that the subsequent processing conditions are widened, and the demoulding is easier when the sheet is used for the blister processing of packaging materials by users; meanwhile, the smoothness and the transparency of the sheet can be improved.

The mechanism is as follows: after the sheet material formed by rolling comes out from the primary cooling area 4, the temperature is still higher, under the action of tensile force, the sheet material is longitudinally stretched and deformed (namely, elastically deformed) greatly, and transversely shrinks under the action of plastic rebound characteristics (under the action of transverse no external force and elastic force, a transverse film is curled and retracted), namely, at the moment, the transverse width of the sheet material is smaller than the transverse width of the sheet material which enters the primary cooling area 4 initially after rolling, if at the moment, the sheet material is cooled and stimulated at lower temperature, the retractility of the sheet material is restricted, the rigidity degree of the sheet material is improved, and the transverse width narrowing speed is reduced, so that in the subsequent continuous cooling process, the thickness of two sides of the sheet material is fixed, the larger shrinkage phenomenon cannot occur, and the thickness cannot be increased. Thus, when the plastic suction machine is used for the plastic suction processing of the packing material, the excess material accumulation phenomenon that the transverse edge area of the sheet material is positioned at the corner part (the transverse edge of the sheet material) of the plastic suction forming object can not be serious (the excess material is accumulated, the sheet material can generate wrinkles during the plastic suction, namely, when the plastic suction machine is heated, the thickness of the sheet material at the accumulation part of the excess material is larger, and the surface of the accumulation part of the excess material is unsmooth after the plastic suction in appearance.

For example: the side length of a square sheet before plastic uptake is 600mm, the longitudinal length of the square sheet after plastic uptake top molding (heating the square sheet during plastic uptake) is shrunk to 590mm, and the transverse width of the square sheet is extended to 602 mm. The reason is that: in the preparation process, the sheet is longitudinally subjected to a large stretching force, so that the longitudinal heated shrinkage rate is large, the sheet is not transversely subjected to the stretching force, the sheet is in a plastic shrinkage state in the cooling and heat preservation processes, the thickness of the two transverse sides of the sheet can be thickened, and the sheet can be outwardly extended after being heated, so that the sheet is transversely widened.

After the improvement of the section of the process, the transverse width of the sheet is shaped before large shrinkage, namely the rigidity of the sheet is improved, and at the moment, the transverse width is kept in a thin state (before plastic shrinkage occurs) to be shrunk, so that the sheet shrinks when being heated during plastic sucking and top molding, and the phenomenon that the sheet extends outwards when being heated is avoided.

In addition, after the process is added, the conveying speed of the sheet can be reduced from 20m/min to 15m/min (the energy consumption of the related driving device is effectively reduced) under the condition of the room temperature holding zone 6 with the same length, and the quality of the sheet can still be maintained under the condition. That is, the PVC sheet 1 entering the room temperature holding section 6 through the rigidity-enhancing section 5 is restricted in its plastic resilience in the longitudinal and width directions, and even if the subsequent stretching force (slower sheet conveying speed) is weak, the longitudinal and transverse shrinkage of the sheet is not greatly reduced as compared with the case where the conveying speed is 20 m/min.

10. Room temperature insulating region 6

As shown in fig. 1 and 4, the rigidity increasing section 5 is provided with 14 thin rolls (cooling rolls 61 arranged at intervals in the same plane), and the two adjacent rolls rotate in opposite directions to further stretch and convey the formed sheet, and similarly, the PVC sheet 1 is moved between the rolls in the take-up direction by the threading conveyance method. The room temperature heat preservation area 6 is used for reducing the temperature of the PVC sheet 1 which is basically shaped (the longitudinal shrinkage rate and the transverse expansion rate reach the set range) to the room temperature in the gradually reduced heat preservation and cooling environment, so that the quality problems of distortion, wrinkling and the like can not occur in the subsequent packaging and transportation processes.

Of the 14 cooling rollers 61, the first seven rollers are filled with warm water at about 70 ℃ for heat preservation, the warm water is injected from the seventh roller and is discharged from the first roller, because the temperature of the sheet conveyed to the first cooling roller 61 in the room temperature heat preservation zone 6 from front to back is higher than 70 ℃ (if the rigidity increasing section 5 is activated, the temperature of the sheet conveyed to the first cooling roller 61 is about 80 ℃), if the rigidity increasing section 5 is not activated, the temperature of the sheet conveyed to the first cooling roller 61 is about 100 ℃), in order to avoid the bad influence on the shaped sheet caused by the excessive temperature difference between the sheet and the cooling roller 61, the warm water flowing from back to front can ensure that the temperature of the rollers is slowly reduced from front to back (because the temperature can absorb a part of the heat from the cooling roller 61 in the flowing process from back to front, so to say, when the temperatures flow to the first cooling roller 61, the temperature thereof is higher than the temperature at the time of just injection), so that the temperature of the sheet on the cooling roll 61 is also gradually reduced, and the phenomenon that the temperature is first suddenly reduced and then increased is not caused; cooling water with the temperature of about 25 ℃ is introduced into the last seven rollers to reduce the temperature, the cooling water is injected from the fourteenth roller and discharged from the eighth roller, and the effect generated by the cooling water entering and exiting from the front is the same as that generated in the previous step.

The length x diameter of the cooling roller 61 is preferably 1300mm x 300mm, and 14 cooling rollers 61 are driven by a timing belt.

On the basis that the rigidity of the PVC sheet 1 is increased by the processes of the initial cooling area 4 and the rigidity improving area 5, the PVC sheet 1 is subjected to heat preservation by the room-temperature heat preservation area 6, so that the internal stress of the PVC sheet 1 can be effectively reduced, and the PVC sheet is ensured to have better toughness on the basis of thinner thickness.

11. Online broken recovery unit 7 of rim charge

As shown in fig. 1, 4 and 5, a sheet width cutting device 71 is provided at the tail of the room temperature holding region 6, and cut scrap is crushed by an on-line reclaimer, sent to a scrap reclaiming hopper 74 provided near the cooling pot 102 through a scrap reclaiming air pipe 73, filtered and added into the cooling pot 102 in a measured amount. The advantages are that: the utility model provides a retrieve rim charge on line, solved the storage silo that sets up specially for the rim charge among the prior art (setting up special rim charge storage silo and exist and easily lead to the rim charge because of depositing for a long time and be polluted, set up special land and difficult scientific batching shortcoming, it is pulling out and stacks the rim charge, later in adding the cooling pan 102 by artifical crushing again, it is according to product specification and order requirement batch intermittent feeding into cooling pan 102 to add in raw material to cooling pan 102, this structure both can retrieve the rim charge completely, but also recycle immediately, and can not take place the contaminated phenomenon of rim charge. Meanwhile, the method has the advantages of saving manpower, reducing recovery links and avoiding intermediate pollution.

The online rim charge recycling machine comprises a rim charge guide ring 72, a traction toothed roller, a crushing and cutting part, an exhaust fan and a rim charge recycling air pipe 73.

1) The leftover material guide ring 72 is divided into a left side and a right side which are respectively arranged below the tail end of the frame of the room temperature heat preservation area 6, and the cut left leftover material and the cut right leftover material are sent into a tractor by the leftover material guide ring 72 on the corresponding side, and the tractor is arranged in a recovery box.

2) The traction toothed rollers are arranged on the tractor and are two toothed rollers which are vertically arranged and meshed with each other, the rim charge is clamped between the two traction toothed rollers, and the rim charge is brought into the recovery box along with the opposite rotation of the two toothed rollers.

3) And the crushing and cutting component is arranged in the recovery box and positioned below the traction toothed rollers, crushes the rim charge falling from the traction toothed rollers, and then is sent into the rim charge recovery hopper 74 through a rim charge recovery air pipe 73 by a negative pressure exhaust fan.

12. Sheet tension adjusting device 8 (also called tension device)

As shown in fig. 1, 4, and 5, in general, when the take-up motor outputs a constant output (when the angular velocity is fixed), the linear velocity increases as the winding diameter of the sheet to be taken up changes (from thin to thick), and thus the traction force applied to the finished sheet during the take-up process increases, and if the value exceeds a certain value, the sheet is stretched and the taken-up finished roll becomes irregular.

For this reason, set up this tension adjusting device, in the scheme of this application, install it between the cooling roller 61 of afterbody and the finished product sheet coiling mechanism in room temperature heat preservation district 6, it can be along with the change of the book footpath of finished product rolling, adjusts rolling traction force for rolling tension is stabilized on invariable numerical value all the time, makes the finished product rolling neat, tight and not the flower that draws from this.

The tension adjusting device is composed of a first guide roller 81, a tension supporting roller 82, a tension adjusting swing roller 83 and a second guide roller 84 which are parallel to each other in sequence according to the moving sequence of the sheet. The two ends of the first guiding roller 81, the tensioning supporting roller 82 and the second guiding roller 84 are respectively fixed on the frame plates 85 at the two sides of the assembly line equipment, the first guiding roller 81 can only rotate and can not move, the first guiding roller 81 is positioned at the rear upper part of the tensioning supporting roller 82 (the room temperature insulation area 6 is in the front direction, and the finished sheet winding device is in the rear direction), and the second guiding roller 84 is positioned at the rear or the rear upper part of the tensioning supporting roller 82.

A swing plate 86 is fixedly connected to each end portion of the tensioning supporting roller 82 (a certain distance is left between the swing plate 86 and the corresponding frame plate 85 in the axial direction of the tensioning supporting roller 82), two ends of the tensioning adjusting swing roller 83 are fixedly installed at the lower position of the swing plate 86 (below the tensioning supporting roller 82), the distance between the tensioning adjusting swing roller 83 and the tensioning supporting roller 82 is relatively fixed, acting force is applied to the tensioning adjusting swing roller 83, and the tensioning adjusting swing roller 83 can swing back and forth by taking the tensioning supporting roller 82 as an axis.

In order to ensure that the rolling traction force applied to the finished sheet in the rolling process is constant, the scheme of the application is realized by automatically adjusting the swing angle of the tension adjusting swing roller 83, meanwhile, in order to maintain the force of the rolling traction force acting on the tension adjusting swing roller 83 in a constant state, a linear air cylinder capable of adjusting the air pressure value is connected to the lower position of the swing plate 86, and the pushing direction of a piston rod of the air cylinder is opposite to the direction of the rolling traction force acting on the tension adjusting swing roller 83.

One end part of the roll shaft of the tensioning supporting rotary roller 82 penetrates through a bearing arranged on the corresponding side frame plate 85 to be connected with an angle shifter 87, namely when the swinging plate 86 swings for an angle, the tensioning supporting rotary roller 82 rotates for an angle along with the rotation, the angle shifter 87 detects electric signal information of the swinging plate 86 swinging for an angle, the electric signal information is transmitted to a PLC automatic control and monitoring system, and the PLC automatic control and monitoring system determines to perform speed reduction or speed increase processing on the winding motor. The speed-up or speed-down operation is started after the winding traction force received by the swinging plate 86 exceeds a set range (is lower than the lower limit of the set range or higher than the upper limit of the set range) by setting the air pressure value range of the air cylinder.

The running sheet is threaded in the tension adjusting device before being wound in the following mode:

the sheet conveyed from the room temperature heat preservation area 6 passes through the first guide roller 81 from front to back, passes through the tension support roller 82 from back to front, passes through the tension support roller 82 from above, passes through the tension adjustment swing roller 83 from front to back, passes through the second guide roller 84 from below, and is wound on the finished sheet winding roller, and the finished sheet winding roller is driven by the winding motor to rotate at a set speed.

Tensioning adjustment principle:

when the winding traction force is large, the tensioning adjusting swing roller 83 swings from front to back below the tensioning supporting roller 82 (namely, the sheet is tight in the winding direction), the swing causes the swing plate 86 to drive the tensioning supporting roller 82 to rotate, the rotation of the tensioning supporting roller 82 enables the angle shifter to capture a rotation signal and transmit the rotation signal to the PLC automatic control and monitoring system, the PLC automatic control and monitoring system compares the rotation signal with the traction force set value stored in the PLC automatic control and monitoring system, when the winding traction force exceeds the set value, the PLC automatic control and monitoring system controls the winding motor to reduce the rotation speed, otherwise (when the tensioning adjusting swing roller 83 swings from back to front at a large angle, namely, the sheet is loose in the winding direction), the rotation speed of the winding motor is improved.

13. Sheet finished product winding device 9

As shown in fig. 1 and 5, the winding is performed by using a horizontally disposed winding roll, which is a conventional apparatus. The roll speed of the curling roll for rolling the sheet material is matched with the linear speed in a set range all the time through a pneumatic device, an angle positioner and a main control circuit (comprising a programmable controller).

14. PLC automatic control and monitored control system.

The utility model discloses a temperature of 2 each calender rolls of mould temperature machine master control platform control calender replaces the accuse temperature that adopts the boiler accuse temperature among the prior art, the advantage: the safety is improved (the boiler is easy to generate gas due to heat conduction oil, and accidents are caused by pressure loss and dry burning of pipelines), the pipelines are shortened, the heat loss is reduced, the energy is saved, and the controlled temperature is more stable.

Claims (5)

1. The utility model provides a cooling device after calendering molding in production PVC sheet equipment, is including leading away initial section cooling area (4) and room temperature heat preservation district (6) after roller (3), its characterized in that: between initial stage cooling zone (4) and room temperature heat preservation district (6), be equipped with one and improve the rigidity of PVC sheet (1) improves the station, and this rigidity improves the station and comprises a basin (53), a rubber roll (51) and a steel roller (52), and steel roller (52), rubber roll (51) and basin (53) from top to bottom horizontal arrangement in proper order on the vertical direction, the basal surface of rubber roll (51) immerses in basin (53), pass between PVC sheet (1) by the pressfitting together and relative rotation's steel roller (52) and rubber roll (51).

2. The cooling device for PVC sheets manufactured by the equipment according to claim 1, which is formed by calendering, is characterized in that: circulating ice water with the temperature of 13-17 ℃ is injected into the water tank (53).

3. The cooling device for PVC sheets manufactured by the equipment according to claim 2, which is formed by calendering, is characterized in that: the steel roller (52) can move up and down in the vertical direction, and two ends of the steel roller (52) are respectively connected with a piston rod of a vertically arranged air cylinder.

4. The cooling device for PVC sheets manufactured by the equipment according to claim 3, which is used after calendering molding, is characterized in that: the diameter of the steel roller (52) is 300-350 mm; the diameter of the rubber roller (51) is 400-600 mm.

5. The cooling device for PVC sheets manufactured by the equipment according to claim 2, which is formed by calendering, is characterized in that: the water tank (53) is internally provided with a temperature sensor which is electrically connected with a main control circuit of the assembly line equipment, and the main control circuit opens or closes an ice water supply valve arranged on the water tank (53) and a water outlet valve for discharging the heated ice water in the tank in real time according to a set water temperature range.

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