CN106426630B - Method and equipment for preventing material overflow in continuous dehydration and drying process by vacuum auxiliary screw extrusion of rubber - Google Patents

Abstract

The invention discloses a method and equipment for preventing material overflow in continuous dehydration and drying by extruding a rubber vacuum auxiliary screw rod, aiming at achieving the purpose that people can prevent rubber from leaking during dehydration and exhaust by using a technical means of a material overflow preventing and exhausting device with a motor-controlled shaftless screw device; the moisture in the sizing material overflows through mechanical extrusion and twice negative pressure, the sizing material is dried more fully through the twice negative pressure overflow of the moisture, and a more complex circuit control device is not required to be connected, so that the operation is simple and convenient.

Description

Method and equipment for preventing material overflow in continuous dehydration and drying process by vacuum auxiliary screw extrusion of rubber

Technical Field

The invention belongs to the field of post-treatment of synthetic rubber or wet-process mixed rubber, and relates to a vacuum-assisted screw extrusion dehydration drying method and equipment.

Background

The drying of rubber is an important process in the rubber production process, which has a considerable proportion in terms of total production energy consumption, equipment investment and operation cost, and meanwhile, the drying process also directly influences parameters such as color, volatile content, polymer degradation and crosslinking degree of a rubber product.

In the early 40 s of the 20 th century, the production flow field of emulsion styrene butadiene rubber was developed in the United states, and a drying process of absorbing and filtering water by a vacuum rotary drum, crushing and putting into a drying oven is adopted in the post-treatment; in the 50 s, a mechanical extrusion dehydrator replaces a vacuum rotary drum device, and the technological process of extrusion dehydration and box-type drying is developed; in the early 60 s, the important progress of a mechanical drying method is taken, and an extrusion dehydration-expansion drying unit is widely applied due to the superior dehydration property; with the vigorous development of the rubber extruder industry, the rubber material is directly dried by using the extruder, and the rubber extruder is vigorously developed due to the advantages of simple process, low equipment cost, low energy consumption and the like. Nowadays, a common rubber drying device is a vacuum drum, a mechanical extrusion dehydrator, an expansion dryer, a microwave, far infrared, a drying box, a screw extruder, and the like. The screw extruder extrusion dehydration drying equipment has the advantages of good dehydration effect, high production capacity, low operation cost and energy consumption, small equipment volume, convenient operation, simple maintenance, convenient automation, suitability for the production of various synthetic rubbers or wet mixing rubbers and the like, and is widely applied to the field of dehydration drying flow fields of rubber products; chinese patent 201420350935.8 discloses a vacuum extrusion dehydrator, which comprises a frame and an extrusion box body arranged on the frame, wherein the extrusion box body comprises a vacuum energy accumulator, a vacuum separation chamber is further arranged between a feed inlet and the extrusion box body, a second water filtering cylinder is arranged in the vacuum separation chamber, the vacuum energy accumulator is arranged on one side of the vacuum separation chamber, the upper end of the vacuum energy accumulator is connected with the vacuum separation chamber through a pipeline, the upper part of the vacuum energy accumulator is also connected with a vacuum pipeline through a negative pressure control valve, a water outlet is further arranged below the vacuum energy accumulator, a drain valve is arranged on the water outlet, the vacuum separation chamber and a screw extruder are combined into one, the manufacturing cost and the installation space of the equipment are greatly saved, the production efficiency of the equipment is improved, but the water in the slurry is absorbed into the vacuum energy accumulator by utilizing the negative pressure in the vacuum energy accumulator through the negative pressure control valve; chinese patent 201120122077.8 discloses an extrusion dehydrator, which comprises a base, and a driving motor, a gear reducer, a charging hopper, a feeding dehydration section, an adjustable pressing plate and a dicing box which are arranged on the base, wherein the feeding dehydration section comprises a conical barrel, a straight barrel and screws arranged in the two barrels, and the lower part of the charging hopper is sequentially provided with a dehydration screen and a drainage box. The conical barrel body is matched with the conical screw, so that the compression ratio is increased, the dewatering effect is good, the whole machine is novel and compact in structure, the production efficiency is high, the single machine yield can be improved by about 20%, the energy consumption is saved by about 25%, the whole machine control automation degree is high, the labor intensity of workers is reduced, and the economic benefit is remarkable. The equipment improves the quality of dried products, the prepared finished product particles are uniform, the contact surface of hydrogel and hot air is large, the drying speed is high, the energy consumption is low, and the equipment has good popularization and application values. CN2016205130309 discloses a screw, the screw edges of which are equidistant and not equidistant, the heat transfer effect is better, and the plastic plasticizing effect is better; 201420425712.3 discloses a screw conical shaft squeezing dehydrator, which is structurally characterized in that a screen inside a box body is provided with a screw conical shaft, the diameter of the screw conical shaft is gradually increased from small to large, the screw pitch is gradually decreased from large to small, holes are arranged on the screen, the left end of the box body is provided with a feeding box, the screw conical shaft is arranged on an end seat, and the bottom of the box body is provided with a waste liquid collecting port; the right end of the box body is provided with the discharge box, and the discharge box is provided with a discharge adjusting device transmission system connected with the spiral conical shaft, so that the sludge dewatering efficiency is improved, and the problem of uneven sludge dewatering of the existing dewaterer is solved; 201420373553.7 discloses an injection molding machine dehumidification anti-overflow material reinforcing device, block up the exhaust vent through the activity stopper, avoid plastic material in ejaculate, the sol and jet move back the possibility that the in-process spills over the raw materials from the exhaust vent, combine to take screw thread to rotate epaxial screw thread of axis and the cooperation of dehumidification feed cylinder again, when taking screw thread axis of rotation to rotate or stop, this screw thread still can produce decurrent extrusion force to the plastic material that upwells, upwelling or spilling over the plastic material have played certain inhibiting action, prevent the possibility that plastic material spills over from the exhaust vent through double cooperation, with the effect that reaches the control raw materials and spills over. 200920035866.0 discloses an anti-overflow exhaust device for vacuum port of twin-screw machine, which comprises a pressure plate with double-arc bottom end, which is matched with the cross section of twin-screw and arranged above the twin-screw. The invention discloses an anti-material-overflow exhaust device of a vacuum port of a double-screw machine, wherein a pressure plate is additionally arranged on one side of the vacuum port, so that gas in a screw is exhausted from the other side of the vacuum port, and the problem of material overflow is solved, 201220543460.5 discloses an internal exhaust type parallel heterodromous multi-screw extruder, which relates to an extrusion molding device using at least two mutually non-meshed screws. 201420862496.9 discloses a material-overflow-preventing exhaust device for vacuum exhaust of a double-screw extruder, which comprises an exhaust seat, wherein each air outlet in the exhaust seat is internally provided with a block, during use, the cylinder and a spring drive the block to do reciprocating motion, if a material overflows from the air outlet, the overflowing material is pressed downwards by the block which moves downwards, and can be taken away by a rotary screw thread groove, so that the exhaust hole can not be blocked by the material all the time. 200820118501.X discloses a feeding device of an extruder, wherein a left bearing seat, a right bearing seat and a feeding roller of the feeding device are different from common structures, and the left bearing seat and the right bearing seat are respectively and completely embedded into ring grooves on the left side and the right side of a feeding roller cover. 201410285605X discloses a rubber extruder side compression roller feeding device, the terminal surface final phase width (opening dimension promptly) of anti-rubber screw thread is unanimous with the slot width of anti-rubber screw thread on the other compression roller, the thickness of doctor-blade is greater than the slot width of anti-rubber screw thread, make the doctor-blade play the shutoff effect to the notch, can ensure that the sizing material does not spill, thoroughly solve the extruder and leak the harmful effects to the environment, also prevent the waste that the hourglass caused, and simultaneously, the quality of extruder products has been improved. The comparison document belongs to the same technical field as the technical scheme, wherein 201420373553.7 is the closest prior art, but the screw teeth of the screw can also generate downward extrusion force on upwelled plastic raw materials, so that the upwelling or overflowing of the plastic raw materials is restrained to a certain extent, but the invention does not disclose the anti-counterfeiting shaftless screw device which is controlled by a motor and forms an angle with the axis, the technical scheme disclosed in the comparison document needs to be connected with a more complex circuit control device, the operation is complicated, the material is easy to flow out from the exhaust port of the extruder, the equal-depth variable-pitch screw is not disclosed, the compression ratio is increased in the compression section, the temperature and the pressure are gradually increased, so that the water in the rubber material is extruded, and when the rubber is fed to the exhaust section, because the screw grooves are deeper, the screw pitch is larger, so that lower pressure is formed, so that water molecules, air and low-molecular volatile matters in the rubber escape, the rubber is pumped out by a vacuum pump through the exhaust hole, so that the technical scheme of dehydration and drying of the rubber is realized, and a material overflow preventing exhaust device is not provided, so that the rubber is not practical in actual production.

Disclosure of Invention

In order to solve the technical problems, the invention provides a method and equipment for preventing the material overflow in the process of dehydrating and exhausting rubber by using a rubber vacuum auxiliary screw extrusion continuous dehydration drying process, so that people can use a technical means of an anti-material overflow exhaust device with a motor-controlled shaftless screw to prevent the rubber from leaking during the dehydration and exhaust; the moisture in the sizing material overflows through mechanical extrusion and twice negative pressure, the sizing material is dried more fully through the twice negative pressure overflow of the moisture, and a more complex circuit control device is not required to be connected, so that the operation is simple and convenient.

In order to achieve the purpose, the technical scheme of the invention is as follows: a rubber vacuum auxiliary screw extrusion continuous dehydration anti-overflow material device comprises a main body structure of a machine head opening die, a machine head jacket, a shunt shuttle, a nested body, a connector, a machine barrel section, a cooling water jacket section, a lining, a first vacuumizing device, a machine barrel section, a cooling water jacket section, a screw, a second vacuumizing device, a machine barrel section, a cooling water jacket section, a feeding device, a reduction box, a base and a support, wherein the machine head is composed of four parts of the machine head opening die, the machine head jacket, the shunt shuttle and the nested body; the machine head is connected with the machine barrel through a connector, and the connector is connected with the machine head and the charging barrel through bolts and threads respectively; the screw is divided into a feeding section, a compression section, a first exhaust section, a homogenization section, a second exhaust section, a second homogenization section, a first vacuumizing device and a second vacuumizing device according to the functions of the screw, the first vacuumizing device and the second vacuumizing device are respectively arranged at the connection part of every two sections of the three machine barrels, matched with the first and second exhaust sections of the screw, the right end of the screw is provided with a bearing and is connected with a gear in a reduction gearbox through a spline gear sleeve, the machine barrel is connected with a bracket, the bracket is fixed on a base, a motor is respectively connected with the reduction gearbox, the screw is an equal-depth and unequal-distance screw except the exhaust sections, the lead of the screw is gradually reduced from the lead of the initial feeding section to the second homogenization section of the screw, the screw pitch and the screw depth of the exhaust section are greater than those of the homogenization section and the feeding section, the first vacuum extractor and the second vacuum extractor are provided with material overflow prevention exhaust devices, and the material overflow prevention exhaust devices are provided with shaftless spiral devices controlled by motors.

The feeding device adopts a side compression roller auxiliary structure and comprises a side compression roller, and the axis of the side compression roller and the axis of the main screw rod form an angle of 30 degrees.

The shaftless spiral device is right-handed, and the included angle between the shaftless spiral device and the axis is 84 degrees, and the glue material overflows with the largest resistance and slowly overflows at the moment.

The movement direction of the screw and the movement direction of the side compression roller auxiliary structure are synchronous and opposite;

the feeding device further comprises a rubber retaining ring, a tapered roller bearing, a sleeve cup, a bearing end cover, a coupler, a CW-type worm gear reducer and a motor, wherein the number of the tapered roller bearings is two, the thread stepped end face of one side compression roller is matched with one tapered roller bearing through the rubber retaining ring, the other tapered roller bearing is matched with the free end stepped end face of the other compression roller, the outer end face of the other tapered roller bearing is matched with the bearing end cover, the tapered roller bearing is matched with the sleeve cup, the bearing end cover is connected with the sleeve cup through a hexagon screw, and the free end of the other compression roller is connected with the CW-type worm gear reducer.

The lead of the screw is 97.5mm at the initial feeding section, the lead of the screw gradually changes to 65mm from the second homogenizing section, the change interval of the helical angle is 12-20 degrees, the helical angle of the screw of the second homogenizing section is 17 degrees and 40 degrees, the screw depth of the feeding section and the homogenizing section is 5mm, and the screw depth of the exhaust section of the screw is 7.5 mm.

The anti-material-overflowing exhaust device further comprises an exhaust connector, an exhaust pipe and a glue storage box, the shaftless spiral is connected with the exhaust connector in a matched mode through a bearing and a gasket from inside to outside in sequence, the exhaust connector, the exhaust pipe and the glue storage box are of an integrated through structure, the free end of the shaftless spiral is connected with the motor through a coupler, and the exhaust pipe is located below the free end of the shaftless spiral and communicated with the section of the shaftless spiral.

The dehydration drying anti-overflow device is an extruder, and the extruder is provided with a second-order vent hole.

The first vacuum pumping device and the second vacuum pumping device further comprise a vacuum pump with a motor, and the vacuum pump is connected with a glue storage box in the anti-counterfeiting exhaust device through an air exhaust pipeline.

The anti-overflowing exhaust device is arranged on one side of the rotation direction of the screw.

A method for preventing material overflow in rubber vacuum assisted screw extrusion continuous dehydration drying comprises the following steps:

(a) turning on a motor, enabling a side compression roller forming an angle of 30 degrees with the axis of the main screw rod to synchronously rotate in different directions with the main screw rod, and feeding the rubber material to a feeding port of a feeding device at a feeding section;

(b) the main screw forwards conveys the rubber material to the compression section, the main screw continuously compresses the rubber material in the region of the compression section, the moisture in the rubber material is continuously extruded out and is discharged through a small water discharge hole at the bottom of the extruder barrel;

(c) opening a control motor and a vacuum pump of the vacuumizing device, enabling the rubber to pass through a first exhaust section, enabling the shaftless spiral in the vacuumizing device controlled by the motor to rotate downwards to prevent the rubber from overflowing, further reducing the area pressure of the rubber under the action of the vacuum pump of the vacuumizing device and the like to form a rubber negative pressure area, enabling water molecules, air and low-molecular volatile matters in the rubber to escape, discharging the rubber out of a machine barrel through the vacuumizing device, carrying out external condensation treatment, and enabling water in the rubber to overflow through mechanical extrusion and twice negative pressure to complete drying treatment;

(d) the main screw forwards conveys the rubber material to a homogenizing section, the anti-overflow exhaust process of the step (c) is completed through a vacuum pumping device, and the rubber material reaches the outlet of the machine head through a second homogenizing section;

(e) and extruding the dried rubber material through a barrel die by a shunt shuttle.

The invention overcomes the defects of the prior equipment and designs a set of synthetic rubber dehydration drying device which consists of a conical double-screw feeding device, a screw extrusion conveying device, a spiral thrust system, a vacuumizing device, a transmission system and the like. The device passes through the toper double screw and accomplishes the feed, realizes the dehydration of sizing material under screw extrusion effect and evacuating device's effect, and the device one-step method accomplishes the dehydration of rubber, and dehydration drying effect is good, the process is continuous, degree of automation is high, utilizes the anti-counterfeiting material exhaust apparatus who has shaftless screw means to prevent that rubber from leaking when the dehydration is discharged and glue, has great practical value.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, but the embodiments of the present invention are not limited thereto.

FIG. 1 is a schematic view of an apparatus for dehydrating and drying rubber to prevent material overflow, according to an embodiment of the present invention;

FIG. 2 is a partial cross-sectional view of a rubber dewatering and drying anti-flash apparatus according to an embodiment of the present invention;

FIG. 3 is a schematic view of an anti-flash exhaust apparatus according to an embodiment of the present invention;

FIG. 4 is a schematic view of a shaftless screw apparatus according to an embodiment of the present invention;

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

As shown in fig. 1, 2 and 3, a rubber vacuum auxiliary screw extrusion continuous dehydration anti-overflow material device comprises a main structure of a machine head bush 1, a machine head jacket 2, a shunt shuttle 3, a nesting body 4, a connector 5, a machine barrel section 6, a cooling water jacket section 7, a lining 8, a first vacuumizing device 9, a machine barrel section 10, a cooling water jacket section 11, a screw 12, a second vacuumizing device 13, a machine barrel section 14, a cooling water jacket section 15, a feeding device 16, a reduction gearbox 17, a base 24 and a bracket 25, wherein the machine head consists of four parts of the machine head bush 1, the machine head jacket 2, the shunt shuttle 3 and the nesting body 4, and the machine barrel consists of three parts of the machine barrel section 6, the machine barrel section 10 and the machine barrel section 14; the machine head is connected with the machine barrel through a connector 5, and the connector 5 is connected with the machine head and the charging barrel through bolts and threads respectively; the screw is divided into a feeding section 18 and a compression section 19 according to the function, a first exhaust section 20, a homogenizing section 21, a second exhaust section 22 and a second homogenizing section 23, a first vacuumizing device 9 and a second vacuumizing device 13 are respectively arranged at the connection part of every two sections of a three-section machine barrel and are matched with the first exhaust section and the second exhaust section of the screw, a bearing is arranged at the right end of the screw 12 and is connected with a gear in a reduction box 17 through a spline gear sleeve, the machine barrel is connected with a bracket 25, the bracket 25 is fixed on a base 24, motors 41 and 42 are respectively connected with the reduction boxes 40 and 17, the screw 12 is a screw with equal depth and different distances except the exhaust sections 20 and 22, the lead is gradually reduced from the feeding section 18 to the second homogenizing section 23 of the screw at the beginning, the pitch and the pitch of the exhaust sections 20 and 22 are greater than the pitch and the pitch of the homogenizing section 21 and the feeding section 18, the first vacuumizing device 9 and the second vacuumizing device 13 are provided with an, the flash-proof exhaust 26 has a shaftless screw 29 controlled by a motor 27.

The feeding device 16 adopts a side pressing roller auxiliary structure and comprises a side pressing roller 34, and the axis of the side pressing roller 34 and the axis of the main screw is 30 degrees.

As shown in FIG. 4, the shaftless screw 29 is right-handed at an angle of 84 to the axis, where the resistance to flow of gum is greatest and the flow is slow.

The feeding device 16 further comprises two rubber blocking rings 35, tapered roller bearings 36, a sleeve cup 37, a bearing end cover 38, a coupler 39, a CW-type worm gear reducer 40 and a motor 41, the threaded stepped end faces of the side pressing rollers 34 are matched with one tapered roller bearing through the rubber blocking rings 34, the other tapered roller bearing is matched with the stepped end face of the free end of the side pressing roller 34, the outer end face of the tapered roller bearing 35 is matched with the sleeve cup 36, the bearing end cover 37 is connected with the sleeve cup 36 through a hexagon screw, the free end of the side pressing roller 34 is connected with the CW-type worm gear reducer 40 through the connecting coupler 39, and the CW-type worm gear reducer 40 is connected with the motor 41.

The lead of the screw 12 in the initial feeding section 18 is 97.5mm, the lead gradually changes to 65mm from the second homogenizing section 23 of the screw, the change interval of the helical angle is 12-20 degrees, the helical angle of the screw in the second homogenizing section 23 is 17 degrees and 40 degrees, the screw depth of the feeding section 18 and the homogenizing sections 21 and 23 is 5mm, and the screw depth of the exhaust sections 20 and 22 of the screw 12 is 7.5 mm.

As shown in fig. 3, the anti-counterfeiting exhaust device 26 further comprises an exhaust connector 31, an exhaust pipe 32 and a glue storage box 33, the shaftless spiral 29 is connected with the exhaust connector 31 in a matching manner through a bearing 30 and a gasket from inside to outside in sequence, the exhaust connector 31, the exhaust pipe 32 and the glue storage box 33 are of an integrated through structure, the free end of the shaftless spiral 29 is connected with the motor 27 through the coupler 28, and the exhaust pipe 32 is located below the free end of the shaftless spiral 29 and communicated with the spiral section of the shaftless spiral 29.

The dehydration drying anti-overflow device is an extruder, and the extruder is provided with a second-order vent hole.

As shown in fig. 2, the first vacuum extractor 9 and the second vacuum extractor 13 further include a vacuum pump 43 with a motor, and the vacuum pump 43 is connected to the glue storage box 33 in the flash-proof exhaust device 26 through an exhaust pipeline.

The anti-flash exhaust device 26 is arranged on one side of the rotation direction of the screw 12.

A method for preventing material overflow in rubber vacuum assisted screw extrusion continuous dehydration drying comprises the following steps:

(a) turning on the motors 41 and 42 to make the side press rolls 34 which form an angle of 30 degrees with the axis of the main screw rod synchronously rotate in different directions with the main screw rod 12, and feeding the rubber material to the feeding port of the feeding device 16 of the feeding section 18;

(b) the main screw 12 conveys the rubber material forwards to the compression section 19, the main screw 12 continuously compresses the rubber material in the compression section area, the moisture in the rubber material is continuously extruded out and is discharged through a small water discharge hole at the bottom of the extruder barrel;

(c) the control motors and the vacuum pumps 43 of the vacuumizing devices 9 and 13 are turned on, the rubber firstly passes through the first exhaust section 20, the shaftless screw 29 in the vacuumizing device 13 controlled by the motors downwards rotates to prevent the rubber from overflowing, the pressure of the area of the rubber is further reduced under the action of the vacuum pumps 43 of the vacuumizing device and the like to form a rubber negative pressure area, water molecules, air and low-molecular volatile matters in the rubber escape, the rubber is exhausted out of a machine barrel through the vacuumizing device 9, the rubber is externally condensed, and the water in the rubber is subjected to mechanical extrusion and twice negative pressure overflow to complete drying treatment;

(d) the main screw 12 forwards conveys the rubber material to the homogenizing section 21, the anti-overflow material exhaust process of the step c is completed through the vacuum pumping device 2, and the rubber material reaches the outlet of the machine head through the second homogenizing section 23;

(e) the dried rubber material is extruded through a barrel die 1 by a shunt shuttle 3.

The invention provides a synthetic rubber dehydration drying device, as shown in figure 2, a bearing is arranged at the right end of a screw 12 and is connected with a gear in a reduction box 17 through a spline gear sleeve, a compression roller beside a feeding device and the screw 12 form 30 ℃ included angle conical arrangement, a machine barrel adopts a sectional type structure, three sections of machine barrels are fastened and connected through bolts, the machine barrels are connected with a machine head through a connector 5, the machine barrel is connected with the connector 5 through threads, and the connector is fastened and connected with the machine head through bolts. As shown in figure 1, synthetic rubber is added through a feed inlet, the feeding capacity is enhanced under the assistance of a press roll 34 beside a feeding device 16, and the feeding is stable; under the actions of shearing and stretching, the temperature and the pressure of the rubber are gradually increased, the rubber is continuously compressed in a screw compression section area, the moisture in the rubber is continuously extruded out and is discharged through a small water discharge hole at the bottom of a machine barrel of the extruder, and most of the moisture in the rubber is compressed and discharged in the compression section area; then, the rubber material passes through the screw exhaust section twice, at the moment, the screw structure is deep in screw groove, the screw pitch is large, the volume of a screw groove cavity is increased, the pressure is reduced, meanwhile, the area pressure is further reduced under the action of a vacuum pump of a vacuumizing device and the like to form a rubber material negative pressure area, water molecules, air and low-molecular volatile matters in the rubber material escape, the rubber material is exhausted out of a machine barrel through the vacuumizing device, external condensation treatment is carried out, and the water in the rubber material is subjected to mechanical extrusion and twice negative pressure overflow to complete drying treatment; and extruding the dried rubber material through a barrel neck mold 1 by a shunt shuttle 3 to obtain a rubber product meeting the performance requirement.

The feeding device 16 of the extruder mainly adopts a spiral feeding device, as shown in figure 1, the axes of the feeding rollers in the feeding device 16 and the axis of the main screw are on the same plane and form a certain angle, preferably 30 degrees; FIG. 3 is a side press roller device disclosed in the embodiment of the present invention, because the rotation direction of the screw thread of the feeding spiral roller 34 is opposite to the rotation direction of the screw thread of the main screw 12, during the operation, the movement direction of the main screw 12 is opposite to the movement direction of the feeding screw 34, and the synchronous and opposite screw directions can greatly enhance the feeding capability of the rubber compound, so that the rubber compound can automatically move forward under the action of the spiral thrust of the feeding roller 34, the feeding roller 34 is driven by a single motor 41 alone, and completes feeding together with the main screw 12, and is decelerated by a reduction box 40; the feeding device 16 of the machine mainly utilizes a worm and gear reduction box 40, the model is CW type, the reduction box has small floor area and lower cost, and is suitable for the feeding device, the power of the driving motor is not too large due to the small stress of the feeding roller 34, and the 3kw power model is preferably selected, the axial line of the feeding roller 34 and the axial line of the main screw 12 are 30 degrees, so that enough installation space can be provided for the worm and gear reduction box 40, the component force of the spiral thrust of the feeding roller 34 in the axial direction of the main screw 12 is ensured to be as large as possible, the feeding capacity of the extruder is greatly improved, the machine capacity of the machine is improved, the quality of extruded products is improved, the production efficiency is improved, and the competitive capacity of enterprises in the market is improved.

In order to solve the material emission problem of the vent of the extruder, the design problem of the vent is improved, the structure of the vent is improved, the size of the designed vent is wider than the width of the material flow, so that the vent of the extruder can be ensured not to be blocked by the flowing melt rubber, and meanwhile, the width of the vent hole of the extruder is not too large, so as to shorten the rubber retention time and the possibility of rubber expansion; when the rubber material flows through the exhaust section of the extruder, air molecules, water molecules and low molecular substances in the flowing rubber material escape due to sudden increase of the volume of the exhaust section and reduction of pressure intensity, and are pumped away by a vacuum pump from the exhaust hole; as shown in fig. 3, the vacuum-pumping device comprises an anti-material-overflow exhaust device 26, in order to prevent the rubber material from overflowing from the exhaust hole, a shaftless screw device 29 is added on the upper part of the exhaust hole, the driving device of the exhaust device can directly adopt a small-torque motor 27 without a reduction box, and the exhaust device 26 is arranged on one side of the rotation direction of the screw rod to facilitate the rubber material to be discharged; the free end of the shaftless screw 29 is connected with the motor 27 through the coupler 28, the vacuum pump 43 with the motor is connected with the glue storage tank 33 in the anti-overflow exhaust device 26 through an exhaust pipeline, when the rubber sealing device is operated, the motor 27 drives the shaftless screw 29, the screw thrust formed by the rotation of the shaftless screw 29 prevents overflow of glue melt, and because the contact area between the shaftless screw 29 and the glue is small, the rubber sealing device can form large resistance to the glue below, and even if the glue overflows, the overflowed glue can be taken out from the adjacent glue storage tank 33; meanwhile, the vacuum pump 43 operates, gas is exhausted from the middle hollow section of the shaftless screw 29 through the exhaust pipe 32, and the vacuumizing device simultaneously realizes the functions of exhausting rubber and preventing material overflow; it should be noted that, in fig. 3, the glue storage box 33 should adopt a drawer type structure in the prior art to remove the overflowed glue in time.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (1)

1. A method for preventing material overflow in rubber vacuum auxiliary screw extrusion continuous dehydration drying is characterized in that: the method is realized in rubber vacuum auxiliary screw extrusion continuous dehydration and drying anti-overflow equipment, and comprises the following steps:

(a) turning on a motor a (41) and a motor b (42), enabling a side pressing roller (34) which forms an angle of 30 degrees with the axis of the main screw (12) to synchronously rotate in different directions with the main screw (12), and feeding the rubber material to a feeding opening of a feeding device (16) of a feeding section (18);

(b) the main screw (12) conveys the rubber material forward to a compression section (19), the main screw (12) continuously compresses the rubber material in the region of the compression section, the water in the rubber material is continuously extruded out and is discharged through a small water discharge hole at the bottom of the extruder barrel;

(c) a control motor and a vacuum pump (43) of the vacuumizing device are turned on, the rubber material firstly passes through a first exhaust section (20), a shaftless screw (29) in the vacuumizing device controlled by the motor rotates downwards to prevent the rubber material from overflowing, the pressure of the area of the rubber material is further reduced under the action of the vacuum pump (43) of the vacuumizing device to form a rubber material negative pressure area, water molecules, air and low-molecular volatile matters in the rubber material escape, the rubber material is exhausted out of a machine barrel through the vacuumizing device, external condensation treatment is carried out, and water in the rubber material is subjected to mechanical extrusion and twice negative pressure overflow to complete drying treatment;

(d) the main screw (12) conveys the rubber material forwards to a first homogenizing section (21), the anti-material-overflowing and exhausting process of the step (c) is completed through a vacuumizing device, and the rubber material reaches the outlet of the machine head through a second homogenizing section (23);

(e) the rubber material which is dried is extruded out through a machine head neck mold (1) through a shunt shuttle (3);

the main structure of the rubber vacuum auxiliary screw extrusion continuous dehydration drying anti-material-overflow equipment comprises a machine head bush (1), a machine head jacket (2), a shunt shuttle (3), a nest body (4), a connector (5), a machine barrel section (6), a cooling water jacket section (7), a bushing (8), a first vacuumizing device (9), a machine barrel section (10), a cooling water jacket section (11), a main screw (12), a second vacuumizing device (13), a machine barrel section (14), a cooling water jacket section (15), a feeding device (16), a reduction gearbox a (17), a base (24) and a support (25), wherein the machine head consists of the machine head bush (1), the machine head jacket (2), the shunt shuttle (3) and the nest body (4), and the machine barrel consists of the machine barrel section (6), the machine barrel section (10) and the machine barrel section (14); the machine head is connected with the machine barrel through a connector (5), and the connector (5) is respectively connected with the machine head and the material barrel through bolts and threads; the screw is divided into a feeding section (18), a compression section (19), a first exhaust section (20), a first homogenizing section (21), a second exhaust section (22) and a second homogenizing section (23) according to the functions of the screw, a first vacuumizing device (9) and a second vacuumizing device (13) are respectively arranged at the connection part of every two sections of a three-section machine barrel and are matched with the first exhaust section (20) and the second exhaust section (22) of the screw, a bearing is arranged at the right end of a main screw (12) and is connected with a gear in a reduction gearbox a (17) through a spline gear sleeve, the machine barrel is connected with a bracket (25), the bracket (25) is fixed on a base (24), a motor a (41) and a motor b (42) are respectively connected with a reduction gearbox b (40) and a reduction gearbox a (17), the main screw (12) is a screw with equal depth and unequal distances except the first exhaust section (20) and the second exhaust section (22), and the lead is gradually reduced from the feeding section (18) to the second homogenizing section (23), the screw pitch and the screw depth of the first exhaust section (20) and the second exhaust section (22) are greater than those of the first homogenizing section (21) and the feeding section (18), the first vacuum extractor (9) and the second vacuum extractor (13) are provided with a material overflow preventing exhaust device (26), and the material overflow preventing exhaust device (26) is provided with a shaftless screw (29) controlled by a motor c (27);

the feeding device (16) adopts a side compression roller auxiliary structure and comprises a side compression roller (34), the side compression roller (34) and the axis of the main screw (12) form a 30-degree angle, the side compression roller (34) is not stressed greatly, and the motor a (41) has the power of 3kw, so that not only can enough installation space be provided for the reduction gearbox b (40), but also the component force of the spiral thrust of the side compression roller (34) in the axis direction of the main screw (12) is ensured to be as large as possible;

the shaftless spiral (29) is right-handed and has an included angle of 84 degrees with the axis,

the moving direction of the main screw (12) and the moving direction of the side press roll (34) of the side press roll auxiliary structure are synchronous and opposite,

the material overflow preventing and exhausting device (26) is arranged on one side of the rotation direction of the main screw (12), the dewatering, drying and material overflow preventing equipment is an extruder, the extruder is provided with a second-order exhaust hole, and the size of the exhaust hole is larger than the width of the material flow; the lead of the main screw (12) is 97.5mm in the initial feeding section (18), the lead gradually changes to 65mm from the second homogenizing section (23) of the screw, the change interval of the helical angle is 12-20 degrees, the helical angle of the screw of the second homogenizing section (23) is 17 degrees and 40 degrees, the screw depth of the feeding section (18), the first homogenizing section (21) and the second homogenizing section (23) is 5mm, and the screw depth of the first exhaust section (20) and the second exhaust section (22) of the main screw (12) is 7.5 mm;

the material-overflow-preventing exhaust device (26) further comprises an exhaust connector (31), an exhaust pipe (32) and a glue storage box (33), the shaftless spiral (29) is connected with the exhaust connector (31) in a matched mode through a bearing (30) and a gasket in sequence from inside to outside, the exhaust connector (31), the exhaust pipe (32) and the glue storage box (33) are of an integrated through structure, the free end of the shaftless spiral (29) is connected with a motor c (27) through a coupler (28), and the exhaust pipe (32) is located below the free end of the shaftless spiral (29) and communicated with a spiral section of the shaftless spiral (29);

the first vacuum pumping device (9) and the second vacuum pumping device (13) further comprise a vacuum pump (43) with a motor, and the vacuum pump (43) is connected with a glue storage box (33) in the anti-overflow exhaust device (26) through an exhaust pipeline.

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