A flame-retardant sheet production line made of waste plastic and a temperature control method thereof

Abstract

The present application relates to waste plastic recycling technical field, especially to a kind of flame-retardant sheet production line made of waste plastic and temperature control method thereof, production line, middle layer extrusion component, including middle layer extruder, layered extrusion port being arranged on middle layer extruder and second connecting pipe being arranged on layered extrusion port;Inner layer extrusion component, including inner layer extruder, middle extrusion port being arranged on inner layer extruder;Joint extruder head, the middle extrusion port, first connecting pipe and second connecting pipe are connected with joint extruder head, and extrusion part and temperature control component are arranged on the joint extruder head.The PP flame-retardant sheet production line designed in the application can set differentiated temperature gradient for the different melting needs of surface layer, middle layer, inner layer PP flame-retardant raw material, avoid raw material degradation or insufficient melting, ensure the quality of each layer melt.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of waste plastic recycling, and in particular to a PP flame-retardant sheet production line made of waste plastic and a temperature control method thereof. BACKGROUND

[0002] In the prior art, the production line for converting waste plastic into flame-retardant sheet still has multi-dimensional technical pain points, resulting in poor product quality stability, low production efficiency, insufficient environmental compliance, and difficulty in meeting market demand for high-performance regenerated flame-retardant sheet.

[0003] Extrusion molding process is one of the important methods of thermoplastic molding. In the extrusion molding process, the extruder makes the plastic raw material in a viscous flow state after heating into a continuous body with a cross section similar to the shape of the mold through the extrusion mold, and then cools and sets, and finally cuts to obtain the required plastic product.

[0004] In the prior art, when the co-extruder injects the raw material into the mold, the pressure is large, and leakage accidents are prone to occur, affecting the quality of the product. In order to reduce the pressure when the co-extruder injects, the co-extruder is generally placed on the side of the main extruder, and the raw material is injected into the mold from the side surface of the mold.

[0005] However, in the existing extrusion production of PP flame-retardant sheet, it is difficult to immediately perform the cutting action on the raw material after extrusion, and it is difficult to cut the flame-retardant sheet into a specific shape immediately after production. SUMMARY

[0006] This section aims to summarize some aspects of the embodiments of the present application and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of the specification to avoid obscuring the purpose of this section, abstract and title, and such simplifications or omissions cannot be used to limit the scope of the present application.

[0007] In view of the above problems existing in the prior art flame-retardant sheet production line, the present application is proposed.

[0008] Therefore, the purpose of the present application is to provide a flame-retardant sheet production line made of waste plastic and a temperature control method thereof.

[0009] To solve the above technical problems, the present application provides the following technical solutions:

[0010] In a first aspect, the present application provides a production line for flame-retardant sheet made of waste plastic, comprising: a main frame, a surface layer extrusion assembly, including a surface layer extruder, an extrusion port arranged on the surface layer extruder, and a first connecting pipe arranged on the extrusion port; an intermediate layer extrusion assembly, including an intermediate layer extruder, a layered extrusion port arranged on the intermediate layer extruder, and a second connecting pipe arranged on the layered extrusion port; an inner layer extrusion assembly, including an inner layer extruder, an intermediate extrusion port arranged on the inner layer extruder; a combined extruder head, the intermediate extrusion port, the first connecting pipe and the second connecting pipe are connected with the combined extruder head, and the combined extruder head is provided with an extrusion part; a temperature control assembly, including a surface layer extruder temperature control structure, an intermediate layer extruder temperature control structure, and an inner layer extruder temperature control structure; a conveying and cutting assembly arranged near the extrusion part.

[0011] As a preferred scheme of the production line for flame-retardant sheet made of waste plastic, a first pipe cavity is arranged in the combined extruder head, the first pipe cavity is connected with the first connecting pipe, a second pipe cavity is arranged in the combined extruder head, the first pipe cavity is arranged outside the second pipe cavity, the second pipe cavity is connected with the second connecting pipe, and a co-extrusion cavity is formed in the intermediate extrusion port, the first pipe cavity and the second pipe cavity are in communication with the co-extrusion cavity.

[0012] As a preferred scheme of the production line for flame-retardant sheet made of waste plastic, the extrusion part includes a connecting plate connected with the combined extruder head, a retaining groove arranged on the connecting plate, a clamping edge arranged in the retaining groove, a clamping piece arranged in the clamping edge, the clamping piece includes a pressing plate arranged in the clamping edge, a micro motor arranged in the clamping edge, a cam arranged on the micro motor, an edge of the cam abutting against an upper end of the pressing plate, and an elastic piece arranged between the pressing plate and the clamping edge.

[0013] As a preferred scheme of the production line for flame-retardant sheet made of waste plastic, a roller frame is arranged on the main frame, a guide roller is arranged on the roller frame, the guide roller is provided with two, and an extrusion channel is formed between the two guide rollers, a receiving frame is arranged on the main frame close to the roller frame, and the conveying and cutting assembly is arranged on the receiving frame.

[0014] As a preferred scheme of the production line of the flame-retardant sheet made of waste plastics, the conveying and cutting assembly comprises a first receiving plate and a second receiving plate slidably connected to the receiving frame, a first horizontal groove and a second horizontal groove are formed in the inner wall of the receiving frame, and an inclined groove is arranged between the first horizontal groove and the second horizontal groove; a pull-down rod is arranged on the second receiving plate, and a walking wheel is arranged at the lower end of the pull-down rod; the walking wheel is matched with the first horizontal groove, the second horizontal groove and the inclined groove; a conveying member is arranged in the receiving frame; and a cutting member is arranged on the bottom surface of the first receiving plate.

[0015] As a preferred scheme of the production line of the flame-retardant sheet made of waste plastics, the cutting member comprises a plurality of blocking pieces arranged at the lower end of the first receiving plate, a suction plate arranged at the lower end of the first receiving plate, and a plurality of spraying pipes arranged on the suction plate; the blocking pieces comprise a plurality of triangular ring plates which are sequentially sleeved from small to large in size; each triangular ring plate is pushed by a gas cylinder; and the suction plate is arranged between the plurality of triangular ring plates.

[0016] As a preferred scheme of the production line of the flame-retardant sheet made of waste plastics, a movable guide rail is detachably connected to the lower end of the first receiving plate by bolts; a pushing block is slidably connected to the movable guide rail; a lead screw is arranged on the pushing block; a driving motor for driving the lead screw to rotate is arranged at the end of the movable guide rail; and the gas cylinder is arranged on the pushing block.

[0017] A blocking plate for mounting the blocking pieces is arranged at the lower end of the first receiving plate; the triangular ring plates of the blocking plate are detachably connected; and an access hole is formed in the blocking plate corresponding to the triangular ring plates.

[0018] As a preferred scheme of the production line of the flame-retardant sheet made of waste plastics, the triangular ring plate is composed of three groups of hinge-connected cutting piece groups; each cutting piece group comprises a plurality of sequentially hinged cutting piece plates; the cutting piece plates are hinged to a support; a cutting piece is arranged at one end of the cutting piece plate; and a cleaning roller is arranged at the other end of the cutting piece plate.

[0019] In a second aspect, the present application provides a temperature control method of a production line of a flame-retardant sheet made of waste plastics, comprising,

[0020] According to the melting characteristics of the PP flame-retardant raw material, the raw material melting and extrusion gradient temperature is set;

[0021] The melt temperature threshold values in the first connecting pipe, the second connecting pipe and the intermediate extrusion port are set to be 95% of the homogenization zone temperature of the corresponding extruder; when the sensor detects that the temperature of any one of the first connecting pipe, the second connecting pipe and the intermediate extrusion port is lower than the threshold value, the temperature controller of the corresponding extruder automatically starts the heating belt, and the power of the heating belt is dynamically adjusted according to the temperature difference;

[0022] Carry out temperature matching control in the partition of the joint extruder head;

[0023] Carry out temperature fine-tuning control at the extrusion end.

[0024] The beneficial effects of the present application: according to the different melting requirements of the PP flame-retardant raw materials of the surface layer, the middle layer and the inner layer, a differentiated temperature gradient is set to avoid degradation or insufficient melting of the raw materials and ensure the quality of the melt of each layer; through the heat preservation of the connecting pipe and the temperature control of the head partition, the temperature loss in the melt conveying process is reduced, the temperature of the three-layer melt is smoothly transitioned in the co-extrusion cavity, and the interlayer bonding strength is improved; the temperature fine-tuning at the extrusion end solves the problem of sheet edge warping, and through closed-loop control, the temperature fluctuation is small. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor. Among them:

[0026] Figure 1 It is a schematic diagram of the overall structure of the flame-retardant sheet production line made of waste plastics of the present application.

[0027] Figure 2 It is a schematic diagram of the side view of the flame-retardant sheet production line made of waste plastics of the present application.

[0028] Figure 3 It is a schematic diagram of the co-extrusion part structure of the flame-retardant sheet production line made of waste plastics of the present application.

[0029] Figure 4 It is a schematic diagram of the overall structure of the flame-retardant sheet production line made of waste plastics of the present application.

[0030] Figure 5 It is a schematic diagram of the connecting plate structure of the flame-retardant sheet production line made of waste plastics of the present application.

[0031] Figure 6 It is a schematic diagram of the first receiving plate and the second receiving plate structure of the conveying and cutting assembly of the flame-retardant sheet production line made of waste plastics of the present application.

[0032] Figure 7 It is a schematic diagram of the conveying and cutting assembly of the flame-retardant sheet production line made of waste plastics of the present application.

[0033] Figure 8 It is a schematic diagram of the cutting part of the flame-retardant sheet production line made of waste plastics of the present application.

[0034] Figure 9 Cutting sheet board schematic diagram for the production line of the flame-retardant sheet made of waste and old plastic of the present application.

[0035] Explanation of reference signs: 1001, main frame body; 100, surface layer extrusion assembly; 101, surface layer extruder; 102, extrusion port; 103, first connecting pipe; 200, intermediate layer extrusion assembly; 201, intermediate layer extruder; 202, layered extrusion port; 203, second connecting pipe; 204, inner layer extrusion assembly; 2041, inner layer extruder; 2042, intermediate extrusion port; 205, combined extruder head; 206, temperature control assembly; 2061, surface layer extruder temperature control structure; 2062, intermediate layer extruder temperature control structure; 2063, inner layer extruder temperature control structure; 2051, first pipe cavity; 2052, second pipe cavity; 2053, co-extrusion cavity; 300, extrusion part; 301, connecting plate; 302, storage groove; 303, clamping edge; 3041, pressing plate; 3042, micro motor; 3043, cam; 3044, elastic piece; 1002, roller frame; 1003, guide roller; 1004, receiving frame; 400, conveying and cutting assembly; 401, first receiving plate; 402, second receiving plate; 403, first horizontal groove; 404, second horizontal groove; 405, pull-down rod; 4051, walking wheel; 406, conveying part; 4061, rotating wheel; 4062, conveying belt; 4063, sliding block; 500, cutting part; 502, suction cup plate; 503, spraying pipe; 5011, triangular ring plate; 5001, air cylinder; 504, moving guide rail; 505, pushing block; 506, lead screw; 507, baffle; 5012, cutting sheet board; 5013, cut sheet; 5014, cleaning roller. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned objectives, features and advantages of the present application more apparent and comprehensible, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0037] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the connotation of the present application, so the present application is not limited to the specific embodiments disclosed below.

[0038] Secondly, the "one embodiment" or "embodiment" referred to herein means that the specific features, structures or characteristics can be included in at least one implementation of the present application. "In one embodiment" appearing in different places in the specification does not mean the same embodiment, nor is it an embodiment that is separate or selective and mutually exclusive with other embodiments.

[0039] Thirdly, the present application is described in detail in combination with the schematic diagram, in the detailed description of the embodiments of the present application, for the convenience of description, the cross-sectional view of the device structure will be partially enlarged without the general proportion, and the schematic diagram is only an example, which should not limit the scope of protection of the present application herein. In addition, the three-dimensional spatial dimensions of length, width and depth should be included in actual production.

[0040] Embodiment 1

[0041] Reference Figures 1-9 For the first embodiment of the present application, a flame-retardant sheet production line made of waste plastics is provided, which comprises a main frame body 1001, the main frame body 1001 is the main support structure of the whole production line, which adopts a frame form.

[0042] Further, the present application also includes a surface layer extrusion assembly 100, in the embodiment, the surface layer extrusion assembly 100 includes a surface layer extruder 101, an extrusion port 102 arranged on the surface layer extruder 101 and a first connecting pipe 103 arranged on the extrusion port 102, the surface layer extruder 101 is mainly used to provide the outermost layer material of the flame-retardant sheet, the surface layer extruder 101 is an existing double screw extruder, the extrusion port 102 is connected with the surface layer extruder 101 by using a flange structure, the first connecting pipe 103 on the extrusion port 102 is also connected by using a flange structure, and a sealing film is arranged at the connection.

[0043] Further, the present application also includes an intermediate layer extrusion assembly 200, in the embodiment, the intermediate layer extrusion assembly 200 includes an intermediate layer extruder 201, a layered extrusion port 202 arranged on the intermediate layer extruder 201 and a second connecting pipe 203 arranged on the layered extrusion port 202, wherein the intermediate layer extruder 201 is mainly used to provide the intermediate layer material of the flame-retardant sheet, the intermediate layer extruder 201 is an existing double screw extruder, the second connecting pipe 203 keeps parallel with the first connecting pipe 103, and the end part is also provided with a butt joint structure for subsequent communication with a combined extruder head 205, so as to realize the conveying of the intermediate layer melt;

[0044] Further, the present application also includes an inner layer extrusion assembly 204, in the embodiment, the inner layer extrusion assembly 204 includes an inner layer extruder 2041 and an intermediate extrusion port 2042 arranged on the inner layer extruder 2041, the inner layer extruder 2041 is arranged in the central region of the main frame body 1001, the intermediate extrusion port 2042 at the end part thereof directly aligns with the combined extruder head 205, the inner wall of the port is smoothly processed, the flow resistance of the inner layer melt is reduced, and the conveying of the melt is ensured smooth;

[0045] Further, the application also comprises a joint extruder head 205, the intermediate extrusion port 2042, the first connecting pipe 103 and the second connecting pipe 203 are all connected with the intermediate extrusion port 2042, and the extrusion part 300 is arranged on the joint extruder head 205.

[0046] Further, the application also comprises a temperature control assembly 206, the temperature control assembly 206 comprises a surface layer extruder temperature control structure 2061: on the cylinder of the surface layer extruder 101, a heating module and a heat preservation layer are arranged along the screw axis direction in sections, the cylinder is divided into three temperature control zones from the feeding port to the extrusion port 102, two groups of stainless steel heating coils are wound in each temperature control zone, the power of the heating coil is 500 W, and the outer side of the heating coil is wrapped with a ceramic fiber heat preservation layer; a PT100 platinum resistance temperature sensor is embedded in the inner wall of the cylinder in each temperature control zone, the sensor signal is connected to the intelligent temperature controller special for the surface layer extruder 101, and an independent temperature control loop of “heating-heat preservation-detection” is formed.

[0047] Further, the temperature control assembly 206 comprises a middle layer extruder temperature control structure 2062: the heating coil, the heat preservation layer and the temperature sensor are arranged in three temperature control zones, and a matched independent intelligent temperature controller is arranged, but the power of the heating coil is adjusted to 600 W, the parameters of the temperature controller can be individually set, and the temperature control is ensured to be independent of the surface layer temperature control.

[0048] Further, the temperature control assembly 206 comprises a middle layer extruder temperature control structure 2063: the cylinder is divided into three temperature control zones, the power of the heating coil is 400 W, the specifications of the remaining heating coil, the heat preservation layer, the temperature sensor and the temperature controller are consistent with those of the surface layer, and the independent operation is matched with the characteristics of the inner layer raw material.

[0049] On the outer wall of the joint extruder head 205, three independent heating zones are divided according to “the first pipe cavity 2051 (the surface layer melt channel), the second pipe cavity 2052 (the middle layer melt channel) and the co-extrusion cavity 2053 (the three-layer fusion zone)”, a flexible silica gel heating sheet is pasted in each heating zone, the heating sheet covers the outer wall area of the corresponding cavity, and the adjacent heating zones are isolated by heat insulation cotton to prevent heat interference; a PT100 temperature sensor is embedded in the inner wall of each heating zone, the sensor probe is close to the melt flow path, and the detection temperature is ensured to be close to the actual temperature of the melt.

[0050] The sensor signals of the three heating zones are connected to the same cooperative temperature controller, the temperature controller can preset the target temperature of each heating zone, and data interaction is carried out with the intelligent temperature controllers of the extruders, so that the temperature is cooperated.

[0051] Further, the application also comprises a conveying and cutting assembly 400, and the conveying and cutting assembly 400 is arranged close to the extrusion part 300.

[0052] Further, a first pipe cavity 2051 is formed in the combined extruder head 205, the first pipe cavity 2051 is connected with the first connecting pipe 103, a second pipe cavity 2052 is formed in the extruder head, the first pipe cavity 2051 is arranged outside the second pipe cavity 2052, the second pipe cavity 2052 is connected with the second connecting pipe 203, a co-extrusion cavity 2053 is formed in the middle extrusion port 2042, the first pipe cavity 2051 and the second pipe cavity 2052 are both communicated with the co-extrusion cavity 2053.

[0053] As preferred, the first pipe cavity 2051 is connected with the first connecting pipe 103 in abutment for conveying the surface layer melt; the first pipe cavity 2051 is arranged outside the periphery of the second pipe cavity 2052 and connected with the second connecting pipe 203 in abutment for conveying the middle layer melt, the first pipe cavity 2051 and the second pipe cavity 2052 are both communicated with the co-extrusion cavity 2053 through flow channels, so that the three-layer melt can realize the layered convergence of "inner layer-middle layer-surface layer" in the co-extrusion cavity 2053.

[0054] As preferred, the extrusion component 300 is installed on the combined extruder head 205, the connecting plate 301 of the extrusion component 300 is fixed with the combined extruder head 205, the retaining groove 302 is formed on the connecting plate 301, and the clamping piece is installed in the clamping edge 303 in the retaining groove 302.

[0055] In the embodiment, the extrusion component 300 includes the connecting plate 301 connected with the combined extruder head 205, the retaining groove 302 formed on the connecting plate 301, the clamping edge 303 arranged in the retaining groove 302, and the clamping piece arranged in the clamping edge 303.

[0056] Further, in the embodiment, the clamping piece includes the pressing plate 3041 arranged in the clamping edge 303, the micro motor 3042 arranged in the clamping edge 303, the cam 3043 arranged on the micro motor 3042, the edge of the cam 3043 abutting against the upper end of the pressing plate 3041, the elastic piece 3044 arranged between the pressing plate 3041 and the clamping edge 303, and the elastic piece 3044 is a spring in the embodiment, and the above structure constitutes the clamping structure of "cam 3043 driving-elastic resetting", which is used for stabilizing the sheet extrusion form.

[0057] As preferred, the connecting plate 301 is arc-shaped and a plurality of connecting plates 301 are arranged to form an arc-shaped structure, and the pressing plate 3041 is also arc-shaped, and when the plurality of micro motors 3042 are started, there are two modes: 1, synchronous rotation, so that the plurality of pressing plates 3041 can be controlled to slide at the same time; 2, distributed control of the plurality of micro motors 3042, so that the frequency of the fire-retardant sheet pressed by the pressing plate 3041 changes.

[0058] Further, the roller frame 1002 is arranged on the main frame 1001, the guide rollers 1003 are arranged on the roller frame 1002, the guide rollers 1003 are two in number, and an extrusion channel is formed between the two guide rollers 1003, the receiving frame 1004 is arranged on the main frame 1001 close to the roller frame 1002, and the conveying and cutting assembly 400 is arranged on the receiving frame 1004.

[0059] As preferred, one of the roller frames 1002 is arranged away from the combined extruder head 205, and the guide rollers 1003 are also arranged on this roller frame 1002.

[0060] Further, in the embodiment, the conveying and cutting assembly 400 comprises a first receiving plate 401 and a second receiving plate 402 which are slidably connected to the receiving frame 1004, a longitudinal plate which is arranged in the receiving frame 1004, a first horizontal groove 403 and a second horizontal groove 404 which are arranged on the longitudinal plate, the first horizontal groove 403 and the second horizontal groove 404 are horizontally arranged, and an inclined groove is arranged between the first horizontal groove 403 and the second horizontal groove 404, the inclined groove is two in number, the first horizontal groove 403 is two in number and has a height higher than that of the second horizontal groove 404, the inclined groove connects the two first horizontal grooves 403 and the second horizontal groove 404, a running wheel 4051 is arranged on the side wall of the second receiving plate 402, the running wheel 4051 cooperates with the first horizontal groove 403, the second horizontal groove 404 and the inclined groove, a conveying member 406 is arranged in the receiving frame 1004, and a cutting member 500 is arranged on the bottom surface of the first receiving plate 401.

[0061] In the embodiment, the conveying member 406 comprises a plurality of rotating wheels 4061 which are arranged on the side wall of the receiving frame 1004, a conveying belt 4062 which is arranged outside the plurality of rotating wheels 4061, and a sliding block 4063 which is arranged on the conveying belt 4062, the conveying belt 4062 is arranged in a rectangular ring shape, the rotating wheels 4061 are arranged at the four corner positions of the conveying belt 4062, the sliding blocks 4063 are arranged at the upper and lower parallel positions of the conveying belt 4062, a motor is arranged on one of the rotating wheels 4061, when the motor drives the rotating wheel 4061 to rotate, the motor drives the conveying belt 4062 to rotate, and then the moving directions of the two sliding blocks 4063 are opposite, and then the moving directions of the first receiving plate 401 and the second receiving plate 402 are opposite.

[0062] As preferred, a plurality of longitudinally arranged telescopic rods are arranged on the sliding block 4063 corresponding to the second receiving plate 402, the telescopic rods are connected to the second receiving plate 402, a downward pulling rod 405 is arranged at the lower end of the second receiving plate 402, and the running wheel 4051 is arranged at the lower end of the downward pulling rod 405.

[0063] As preferred, the bending plates are arranged on the second receiving plate 402, and are used to limit the fireproof sheet, the cross section of the bending plate is inverted "L" shape, and two bending plates are arranged oppositely.

[0064] Further, in the embodiment, the cutting component 500 comprises a plurality of blocking pieces arranged at the lower end of the first receiving plate 401, a suction plate 502 arranged at the lower end of the first receiving plate 401, and a plurality of spraying pipes 503 arranged on the suction plate 502, the spraying pipes 503 are used to spray the outer film on the surface layer of the manufactured fireproof material, the blocking pieces comprise a plurality of triangular ring plates 5011 which are sequentially sleeved from small to large, each triangular ring plate 5011 is pushed by a pneumatic cylinder 5001, and the suction plate 502 is arranged between the plurality of triangular ring plates 5011.

[0065] As preferred, the sizes of the triangular ring plates 5011 are different, and each triangular ring plate 5011 is formed into a triangle by surrounding with an alloy material iron plate.

[0066] Further, a moving guide rail 504 is arranged at the lower end of the first receiving plate 401, a pushing block 505 is slidably connected on the moving guide rail 504, a lead screw 506 is arranged on the pushing block 505, a driving motor is arranged at the end of the moving guide rail 504 and used to drive the rotation of the lead screw 506, and the pneumatic cylinder 5001 is arranged on the pushing block 505 by bolts.

[0067] As preferred, the moving guide rail 504 can be disassembled, and then the operator can disassemble the moving guide rail 504 and the pneumatic cylinder 5001 synchronously, and then install the moving guide rail 504 and the pneumatic cylinder 5001 at different positions of the triangular ring plates 5011, so as to press different triangular ring plates 5011.

[0068] Further, a plurality of installation grooves are arranged on the suction plate 502 and used to install the spraying pipes 503, and an isolation layer is coated on the inner wall of the triangular ring plate 5011.

[0069] As preferred, a grabbing plate is arranged on the output shaft of the pneumatic cylinder 5001, and the grabbing plate is used to grab the triangular ring plate 5011.

[0070] As preferred, a blocking plate 507 is arranged at the lower end of the first receiving plate 401, the plurality of triangular ring plates 5011 are detachably connected with the blocking plate 507, a plurality of entering holes are arranged on the blocking plate 507 and used for the pneumatic cylinder 5001 to enter, and each entering hole corresponds to one triangular ring plate 5011.

[0071] As preferred, the triangular ring plate 5011 is composed of three groups of mutually hinged cutting piece groups, each cutting piece group including a plurality of sequentially hinged cutting piece plates 5012, the cutting piece plates 5012 being hinged on the triangular ring plate 5011, a cutting piece 5013 being arranged at one end of the cutting piece plate 5012, a cleaning roller 5014 being arranged at the other end, and a rotating shaft of the plurality of cutting piece plates 5012 extending outwardly with an electric control motor.

[0072] Operation process: Put the corresponding formula PP flame-retardant raw materials into the surface layer extruder 101, the middle layer extruder 201 and the inner layer extruder 2041 respectively, set the temperature parameters of each extruder according to the characteristics of the raw materials, and start the extruder. After the extruder runs stably and the screw speed reaches the set value, the raw materials of each layer melt to form a melt, the surface layer melt passes through the first connecting pipe 103, the middle layer melt passes through the second connecting pipe 203, and the inner layer melt passes through the middle extrusion port 2042, and is respectively transported to the corresponding cavity of the combined extruder head 205.

[0073] The surface layer melt enters the co-extrusion cavity 2053 along the first pipe cavity 2051, the middle layer melt enters the co-extrusion cavity 2053 along the second pipe cavity 2052, and the inner layer melt directly enters the co-extrusion cavity 2053. In the co-extrusion cavity 2053, the layered wrapping fusion is realized through the flow channel guide to form a three-layer structure melt of "inner layer-middle layer-surface layer". The fused melt enters the combined extruder head 205, and then is extruded through the storage groove 302 of the connecting plate 301. At this time, the micro motor 3042 of the clamping part is started, the cam 3043 is rotated to push the pressing plate 3041 to move downward, the edge of the extruded sheet is pressed in the storage groove 302 to prevent the edge of the sheet from warping, and the reset action of the elastic member 3044 ensures the stability of the pressing force and guarantees the forming precision of the sheet.

[0074] The formed three-layer co-extrusion sheet enters the extrusion channel between the two guide rollers 1003, and the guide rollers 1003 rotate synchronously to stably transport the sheet to the receiving frame 1004.

[0075] Then the flame-retardant material forms a flat strip, and is received by the second receiving plate 402. The rotation of the rotating wheel 4061 makes the conveying belt 4062 move, and then drives the sliding of the two sliding blocks 4063. Because the moving directions of the two sliding blocks 4063 are opposite, the second receiving plate 402 and the first receiving plate 401 move in opposite directions. Because the walking wheel 4051 at the lower end of the second receiving plate 402 moves along the walking direction of the first horizontal groove 403 and the second horizontal groove 404, when the second receiving plate 402 moves to the lower end of the first receiving plate 401, the flame-retardant sheet is cut by the cutting member 500.

[0076] Example 2

[0077] Reference Figures 1-2The embodiment discloses a temperature control method of a flame-retardant sheet production line made of waste plastics, and comprises the following steps:

[0078] (I) Stage 1: Raw material melting and extrusion temperature gradient setting

[0079] Surface layer extruder 101 temperature setting: according to the melting characteristics of the surface layer PP flame-retardant raw material, the temperature gradient of the three temperature control zones of the cylinder is set as follows: the feeding zone is 160-170 DEG C, the melting zone is 180-190 DEG C, and the homogenizing zone is 190-200 DEG C; the temperature controller adopts PID adjustment, when the sensor detects that the temperature of a certain area is lower than the target value, the power of the corresponding heating ring is automatically increased, and when the temperature is higher than the target value, the power is reduced or the heating is stopped, and the temperature fluctuation range is controlled to be less than or equal to ± 2 DEG C.

[0080] Intermediate layer extruder 201 temperature setting: the intermediate layer raw material has slightly high melting viscosity, and the corresponding temperature gradient is set as follows: the feeding zone is 155-165 DEG C, the melting zone is 175-185 DEG C, and the homogenizing zone is 185-195 DEG C, and the temperature fluctuation control is less than or equal to ± 2 DEG C, and the temperature difference with the surface layer is stably controlled at 5-10 DEG C through independent temperature controller.

[0081] Inner layer extruder 2041 temperature setting: the inner layer raw material is easy to degrade, and a lower temperature gradient is set as follows: the feeding zone is 150-160 DEG C, the melting zone is 170-180 DEG C, and the homogenizing zone is 180-190 DEG C, and the temperature fluctuation control is less than or equal to ± 2 DEG C, and the temperature difference with the intermediate layer is maintained at 5 DEG C, thereby forming the overall temperature gradient of'surface layer> intermediate layer> inner layer'.

[0082] (II) Stage 2: Temperature preservation control of melt conveying channel

[0083] First / second connecting pipe 203 temperature preservation: the melt temperature threshold in the connecting pipe is set as 95% of the homogenizing zone temperature of the corresponding extruder, when the sensor detects that the temperature of the connecting pipe is lower than the threshold, the temperature controller of the corresponding extruder automatically starts the heating belt, and the power of the heating belt is dynamically adjusted according to the temperature difference, so that the temperature of the melt still maintains at more than 95% of the homogenizing zone temperature when the melt reaches the die head, and the viscosity of the melt is prevented from being increased due to temperature drop.

[0084] (III) Stage 3: Partition temperature matching control of combined extruder head 205

[0085] First pipe cavity 2051 temperature control: the target temperature is set as the homogenizing zone temperature of the surface layer extruder 101, the temperature is adjusted through the heating sheet in cooperation with the temperature controller, and the fluctuation control is less than or equal to ± 1 DEG C, so that the temperature of the surface layer melt in the channel is stable, and secondary temperature drop does not occur.

[0086] Second pipe cavity 2052 temperature control: set target temperature = middle layer extruder 201 homogenization zone temperature, temperature difference with first pipe cavity 2051 temperature difference 5-10 DEG C, match melt viscosity difference, avoid layer shear force too large resulting in delamination.

[0087] Co-extrusion cavity 2053 temperature control: set target temperature = (surface layer homogenization zone temperature + middle layer homogenization zone temperature + inner layer homogenization zone temperature) / 3, as transition temperature zone, make three layer melt temperature gradient gentle when fusion, reduce layer combination defects caused by temperature mutation; when sensor detects co-extrusion cavity 2053 temperature deviates from target value, cooperate temperature controller to adjust middle layer heating zone temperature, then fine-tune surface layer and inner layer heating zone, ensure overall temperature stability.

[0088] (Four) stage 4: extrusion molding end temperature fine-tuning control

[0089] Set the target temperature in the storage tank 302 lower than the co-extrusion cavity 2053 temperature, when the sensor detects that the storage tank 302 temperature is too low, cooperate temperature controller to start micro-heating sheet, single group heating sheet power is outputted according to temperature difference proportion, prevent sheet edge warping, cracking due to rapid cooling by local reheat; if temperature is too high, stop micro-heating sheet, use clamping piece heat dissipation to assist cooling, ensure that the sheet temperature is in the best range when forming.

[0090] For different melting requirements of surface layer, middle layer, inner layer PP flame retardant raw materials, set differential temperature gradient, avoid raw material degradation or insufficient melting, ensure each layer melt quality; through connecting pipe heat preservation, temperature control of head partition, reduce temperature loss in melt conveying process, make three layer melt temperature gentle transition in co-extrusion cavity 2053, improve interlayer bonding strength; extrusion molding end temperature fine-tuning, solve the problem of sheet edge warping, at the same time, through closed loop control to ensure temperature fluctuation is small.

[0091] It is important to note that the construction and arrangement of the application shown in the various exemplary embodiments is illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review the present disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter described herein. For example, elements shown as integrally formed can be constructed of multiple parts or elements, the position of elements can be reversed or otherwise varied, and the nature or number of elements or positions can be altered or varied. Thus, the foregoing description is by way of example only, and is not intended to be limiting. The application is limited only as defined in the following claims and equivalents thereto. The sequence of any process or method steps, or the order in which they are carried out, can be altered or re-ordered without departing from the scope of the application. Any "articles of manufacture" or "manufacturing" as described herein are intended to encompass structures constructed of a multitude of different physical elements or components. In the claims, any means-plus-function clause is intended to cover the structures described herein as performing the recited function and also cover structures yet to be invented which perform the recited function but operate in a different manner. Other substitutions, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the application as expressed in the appended claims.

[0092] Also, for example, in the exemplary embodiments, the steps of any processes or methods need not be performed in the exact order disclosed herein unless expressly stated otherwise. In some embodiments, steps can be performed in parallel or concurrently. In addition, certain of the steps can be combined instead of being performed separately or can be stored or distributed in different system architecture now known or later developed. In addition, any of the steps can be performed in multiple sub-steps or in a different order than disclosed or expressed in this specification.

[0093] It is understood that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions can be made. Such development efforts can inevitably lead to modifications, not all of which can be known in advance. Such modifications are typically deemed to be within the scope of the inventive subject matter as expressed in the appended claims.

[0094] It should be noted that the above-mentioned embodiments are only used to illustrate the technical solutions of the present application but not to limit the present application. Although the present application is described in detail with reference to the preferred embodiments, persons of ordinary skill in the art should understand that they can make modifications or equivalent replacements to the technical solutions of the present application without departing from the spirit and scope of the present application, and all these modifications and equivalent replacements should be included in the scope of the claims of the present application.

Claims

1. A production line for flame-retardant sheets made from waste plastics, characterized in that: include: Main frame (1001). The surface extrusion assembly (100) includes a surface extruder (101), an extrusion port (102) disposed on the surface extruder (101), and a first connecting pipe (103) disposed on the extrusion port (102). The intermediate layer extrusion assembly (200) includes an intermediate layer extruder (201), a layer extrusion port (202) disposed on the intermediate layer extruder (201), and a second connecting pipe (203) disposed on the layer extrusion port (202). The inner extrusion assembly (204) includes an inner extruder (2041) and an intermediate extrusion port (2042) disposed on the inner extruder (2041). The combined extruder head (205) is connected to the intermediate extrusion port (2042), the first connecting pipe (103) and the second connecting pipe (203). The combined extruder head (205) is provided with an extrusion component (300). Temperature control components (206) include a surface extruder temperature control structure (2061), an intermediate extruder temperature control structure (2062), and an inner extruder temperature control structure (2063). A conveying and cutting assembly (400) is disposed near the extrusion component (300). A first pipe cavity (2051) is formed inside the combined extruder head (205), which is connected to a first connecting pipe (103). A second pipe cavity (2052) is formed inside the combined extruder head (205), with the first pipe cavity (2051) located outside the second pipe cavity (2052). The second pipe cavity (2052) is connected to a second connecting pipe (203). A co-extrusion cavity (2053) is formed inside the intermediate extrusion port (2042). The first pipe cavity (2051) is located outside the second pipe cavity (2052). Both the extrusion chamber (2051) and the second pipe cavity (2052) are connected to the co-extrusion cavity (2053). The extrusion component (300) includes a connecting plate (301) connected to the combined extruder head (205) and a retention groove (302) opened on the connecting plate (301). A retaining edge (303) is provided in the retention groove (302). A clamping member is provided in the retaining edge (303). The clamping member includes a pressing plate (3041) provided in the retaining edge (303). A micro motor (3042) is provided in the retaining edge (303). A cam (3043) is provided on the micro motor (3042). The edge of the cam (3043) abuts against the pressing plate. An elastic element (3044) is provided between the pressed plate (3041) and the retaining edge (303) along the upper edge of the laminated plate (3041). A roller frame (1002) is provided on the main frame (1001), and guide rollers (1003) are provided on the roller frame (1002). There are two guide rollers (1003), and an extrusion channel is formed between the two guide rollers (1003). A receiving frame (1004) is provided on the main frame (1001) near the roller frame (1002). The conveying and cutting assembly (400) is provided on the receiving frame (1004), and the conveying and cutting assembly (400) includes components that are slidably connected to the receiving frame (1004). The first receiving plate (401) and the second receiving plate (402), the first transverse groove (403) and the second transverse groove (404) opened on the inner wall of the receiving frame (1004), the first transverse groove (403) and the second transverse groove (404) are provided with an inclined groove, the second receiving plate (402) is provided with a pull rod (405), the lower end of the pull rod (405) is provided with a wheel (4051), the wheel (4051) cooperates with the first transverse groove (403), the second transverse groove (404) and the inclined groove, the receiving frame (1004) is provided with a conveyor (406), and the bottom surface of the first receiving plate (401) is provided with a cutting component (500).

2. The flame-retardant sheet production line made from waste plastics as described in claim 1, characterized in that: The cutting component (500) includes several stops at the lower end of the first receiving plate (401), a suction cup plate (502) at the lower end of the first receiving plate (401), and several spray tubes (503) on the suction cup plate (502). The stops include several triangular ring plates (5011) of increasing size, which are nested together. Each triangular ring plate (5011) is pushed by a cylinder (5001). The suction cup plate (502) is disposed between the triangular ring plates (5011).

3. The flame-retardant sheet production line made from waste plastics as described in claim 2, characterized in that: The lower end of the first receiving plate (401) is detachably bolted to a movable guide rail (504), a push block (505) is slidably connected on the movable guide rail (504), a lead screw (506) is provided on the push block (505), a drive motor for driving the lead screw (506) to rotate is provided at the end of the movable guide rail (504), and a cylinder (5001) is provided on the push block (505); The lower end of the first receiving plate (401) is provided with a baffle (507) for installing a stop. The baffle (507) is detachably connected to the triangular ring plate (5011). An entry hole is provided on the baffle (507) corresponding to the triangular ring plate (5011).

4. The flame-retardant sheet production line made from waste plastics as described in claim 3, characterized in that: The triangular ring plate (5011) consists of three sets of cutting blade groups that are hinged to each other. Each cutting blade group includes several cutting blade plates (5012) that are hinged to each other in sequence. The cutting blade plates (5012) are hinged to the triangular ring plate (5011). One end of the cutting blade plate (5012) is provided with a cutting blade (5013), and the other end is provided with a cleaning roller (5014).

5. A temperature control method for a flame-retardant sheet production line made from waste plastics as described in any one of claims 1-4, characterized in that: include, Based on the melting characteristics of PP flame-retardant raw materials, the gradient temperature for raw material melting and extrusion is set; The melt temperature threshold in the first connecting pipe (103), the second connecting pipe (203), and the intermediate extrusion port (2042) is set to 95% of the temperature of the homogenization zone of the corresponding extruder. When the sensor detects that the temperature of any one of the components in the first connecting pipe (103), the second connecting pipe (203), and the intermediate extrusion port (2042) is lower than the threshold, the temperature controller of the corresponding extruder automatically starts the heating belt, and the power of the heating belt is dynamically adjusted according to the temperature difference. Perform zoned temperature matching control within the combined extruder head (205); Perform fine-tuning control of the extrusion molding end temperature.

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