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CN-122008438-A - Foaming polypropylene particle production line and production method thereof

CN122008438ACN 122008438 ACN122008438 ACN 122008438ACN-122008438-A

Abstract

The invention belongs to the technical field of polypropylene particle production, in particular to a foaming polypropylene particle production line and a production method thereof, comprising a particle screening component, wherein the particle screening component is placed on the ground, the particle screening component is arranged at the bottom of granulating equipment and is used for screening the foaming polypropylene particles according to the specification, and simultaneously, the particle screening component is used for discharging the particles meeting the specification, the invention can keep the gas in the foaming process in the resin matrix, reduce the foaming difficulty of polypropylene particles, further stabilize the performance of the foamed polypropylene particles, realize the integrated operation of drying treatment, premixing and melting of pretreatment equipment, reduce various equipment of a production line, reduce the purchase cost of the equipment, and reduce the operation steps in production, thereby increasing the production rate of polypropylene particles.

Inventors

  • YAO XIAOTONG
  • Yuan Longshan
  • WANG ZHEN
  • LU FEI

Assignees

  • 徐州聚西廷新型材料科技有限公司

Dates

Publication Date
20260512
Application Date
20251231

Claims (10)

  1. 1. A expanded polypropylene particle production line comprises a particle screen assembly (6); a particle screening assembly (6) placed on the ground, wherein the particle screening assembly (6) is arranged at the bottom of the granulating equipment (5) and is used for screening the foamed polypropylene particles according to particle specification through the particle screening assembly (6) and discharging the particles meeting the specification at the same time; Characterized by further comprising: A pretreatment device (1) which is installed and placed through a bracket (55) at the top of the granulating device (5), and the pretreatment device (1) is installed at the right end of the bracket (55), and is used for the integrated operation of drying, premixing and melting PP granules through the pretreatment device (1); the foaming storage and metering device (2) is arranged and placed through a bracket (55) at the top of the granulating device (5), is arranged at the left end of the bracket (55), is used for storing the foaming agent through the foaming storage and metering device (2), and is used for injecting and discharging the foaming agent according to the metering value through the driving of the foaming storage and metering device (2); The top of the transportation device (3) is provided with two ports, one port is connected to the bottom of the pretreatment equipment (1), the other port is connected to the bottom of the foaming storage and metering equipment (2), the bottom port of the transportation device (3) is connected to the top of the mixing component (4), and an air pump is externally connected to the transportation device (3) for simultaneously transporting materials in the pretreatment equipment (1) and the foaming storage and metering equipment (2); the mixing component (4) is arranged at the bottom of the conveying device (3) and is arranged on the surface of the granulating equipment (5), and is used for mixing the foaming agent and the PP particles in a molten state through the cooperation of the conveying device (3) and the mixing component (4), and simultaneously, the foaming agent and the PP particles in the molten state are mixed to generate bubbles, so that the mixed materials are expanded, and then the continuous mixing and stirring are carried out through the mixing component (4), so that the foaming process is completed; The granulating device (5) is arranged at the lower ends of the pretreatment device (1) and the foaming storage and metering device (2), the granulating device (5) is externally connected with a water pump, circulating cold water continuously passes through the inside of the granulating device (5) through the water pump externally connected with the granulating device (5), so that the mixed material discharged by the mixing assembly (4) is cooled, and meanwhile, the cooled mixed material is pressed and rolled through the driving of the granulating device (5), and cooled and molded foaming particles are discharged.
  2. 2. A expanded polypropylene particle production line according to claim 1, wherein the pretreatment device (1) comprises: a pretreatment module (11) which is installed and placed by a bracket (55) at the top of the granulating apparatus (5) and is installed at the right end of the bracket (55); A built-in housing (12) provided on the outer wall of the pretreatment module (11); And a stirring assembly (13) arranged on top of the pretreatment assembly (11).
  3. 3. A expanded polypropylene particle production line according to claim 2, wherein the pre-treatment assembly (11) comprises: A pretreatment tank (111) mounted and placed by a bracket (55) at the top of the granulating apparatus (5) and mounted at the right end of the bracket (55); a bellows (112) provided around the inner wall of the pretreatment housing (111); heating plates (113) which are provided around the inner wall of the pretreatment housing (111) and between the bellows (112); a blanking valve (114) which is arranged at the bottom of the pretreatment box body (111) and enables the upper end of the surface of the blanking valve (114) to be provided with a heating coil; The stirring assembly (13) comprises: A cover plate (131) provided on the top of the pretreatment tank (111); An air outlet (132) provided at the top right end of the cover plate (131); an injection port (133) provided at the top left end of the cover plate (131); A stirring driving motor (134) provided at the top center of the cover plate (131); The rotating rod (135) is rotatably connected to the bottom center of the cover plate (131), and the top port of the rotating rod (135) is connected with the output end of the stirring driving motor (134); And a heating rod (136) arranged around the outer wall of the rotating rod (135).
  4. 4. A expanded polypropylene particle production line according to claim 1, wherein the expanded storage and metering device (2) comprises: A storage metering assembly (21) mounted and placed by a stand (55) at the top of the granulation apparatus (5) and mounted at the left end of the stand (55); the storage metering assembly (21) comprises: a storage tank (211) installed and placed by a stand (55) at the top of the granulating apparatus (5) and installed at the left end of the stand (55); a transparent plate (212) provided at the front end of the surface of the storage box (211); a measurement scale (213) provided on the outer wall of the storage box (211); an injection outlet (214) provided at the bottom of the storage tank (211); an injection drive assembly (22) disposed on top of the storage metering assembly (21); The injection drive assembly (22) comprises: a storage cover plate (221) provided on the top of the storage box (211); an injection hydraulic cylinder (222) provided on the top of the storage cover plate (221); And an injection plug (223) which is slidably connected to the inside of the storage tank (211) and connects the top of the injection plug (223) to the output end of the injection hydraulic cylinder (222).
  5. 5. A expanded polypropylene particle production line according to claim 1, wherein the transportation means (3) comprises: a diversion assembly (31) which is arranged at the bottom of the pretreatment equipment (1); The flow guiding assembly (31) comprises: A first installation tube (311) installed at the bottom of the pretreatment apparatus (1); a flow guide pipe (312) installed on the inner wall of the first installation pipe (311); A second mounting tube (313) provided at the bottom of the first mounting tube (311); A first electromagnetic valve (32) mounted at the bottom of the diversion assembly (31), and having the bottom of the first electromagnetic valve (32) mounted at the top right port of the transport assembly (34); A second electromagnetic valve (33) mounted at the bottom of the foaming storage and metering device (2), and having the bottom of the second electromagnetic valve (33) mounted at the top left side port of the transport assembly (34); the two ends of the top of the transport assembly (34) are provided with a first electromagnetic valve (32) and a second electromagnetic valve (33), and the bottom port of the transport assembly (34) is connected with the top of the mixing assembly (4); The transport assembly (34) includes: a first connection pipe (341) installed at the bottom of the first electromagnetic valve (32), and the first connection pipe (341) is externally connected with an air pump; A Y-shaped pipe (342) provided at the bottom of the first connection pipe (341) and having the top right end of the Y-shaped pipe (342) connected to the bottom of the first connection pipe (341); and a second connection pipe (343) which is arranged at the left end of the top of the Y-shaped pipe (342) and connects the top of the second connection pipe (343) with the bottom of the foaming storage and metering device (2).
  6. 6. A expanded polypropylene particle production line according to claim 1, wherein the mixing assembly (4) comprises: A mixing box (41) with a top center mounted at the bottom of the transport device (3); A spiral pipe (42) which is provided at the upper end of the inside of the mixing box (41) and connects the top of the spiral pipe (42) with the output end of the bottom of the transporting device (3); A mixing bottom plate (43) installed at the bottom of the mixing tank (41) such that the bottom of the mixing bottom plate (43) is installed at the top of the granulating apparatus (5); And a flow turbine (44) rotatably connected to the top center of the mixing floor (43) with the bottom opening of the spiral pipe (42) facing the upper end side of the flow turbine (44).
  7. 7. A expanded polypropylene particle production line according to claim 1, wherein the granulation apparatus (5) comprises: an introduction assembly (51) having a top center mounted at the bottom of the mixing assembly (4); a granulation outer shell (54) provided at the bottom of the introduction assembly (51); A granulation driving assembly (52) mounted at an inner upper end of the granulation housing (54) and having a bottom of the granulation driving assembly (52) slidably connected to a top of the granulation mold assembly (53); a granulation die assembly (53) which is provided at the lower end of the inside of the granulation housing (54) and which has a circulation pipe provided inside the granulation die assembly (53) while being externally connected to a circulation water pump so that the water pump circulates cold water into the inside of the circulation water pipe; And a bracket (55) mounted on the top rear end of the introduction assembly (51).
  8. 8. A expanded polypropylene particle production line according to claim 7, wherein the introduction assembly (51) comprises: an introduction plate (511) having a top center installed at the bottom of the mixing assembly (4); an inlet (512) provided at the top front end of the inlet plate (511), the inlet (512) being connected to the bottom port of the mixing unit (4); A guide plate (513) which is provided inside the inlet (512) and in which the rear end of the guide plate (513) is inclined toward the lower end; the granulation drive assembly (52) comprises: An upper granulation die (521) slidingly coupled to a surface of the granulation die assembly (53); An extension plate (522) provided at the top front end of the granulation upper die (521); a first granule tank (523) provided at the bottom of the granulation upper die (521); a baffle (524) provided at the inner front end of the first particle tank (523); the rear ends of the electric telescopic rods (525) are connected to the two ends of the rear end of the inner wall of the granulating outer shell (54), the output ends of the electric telescopic rods (525) are connected to the rear ends of the extension plates (522), and meanwhile, the electric telescopic rods (525) are arranged in two groups; The granulation mould assembly (53) comprises: A granulation lower die (531) provided at the lower end of the inside of the granulation outer casing (54) and having a circulation water pipe provided inside the granulation outer casing (53), the circulation water pipe being externally connected to a circulation water pump so that the water pump circulates cold water into the circulation water pipe; A second granulation tank (532) provided on the surface of the granulation lower mold (531); And a particle outlet groove (533) provided at the rear end of the surface of the second particle groove (532).
  9. 9. A expanded polypropylene particle production line according to claim 1, wherein the particle screen assembly (6) comprises: a sieving housing (61) having a top mounted at the lower end of the granulating apparatus (5); a screening outlet (62) provided on the lower side of the front end of the screening housing (61); a first screening plate (63) mounted at an inner upper end of the screening housing (61); a second screening plate (64) mounted in the middle of the interior of the screening housing (61); a third screening plate (65) mounted at the inner lower end of the screening housing (61); And a sealing plate (66) mounted on the bottom of the sieving housing (61).
  10. 10. A method for producing expanded polypropylene particles according to claims 1 to 9, comprising the following operative steps: S1, placing PP particles into a pretreatment box body (111), starting a bellows (112), a heating plate (113) and a heating rod (136), starting a stirring driving motor (134), driving the PP particles to stir in the pretreatment box body (111), and continuously gathering the centrifuged PP particles inwards through the bellows (112), so that the PP particles are quickly and uniformly heated and dried, moisture in the PP particles is removed, and bubbles are prevented from being generated in the production process; S2, after the drying is finished, injecting auxiliary raw materials into the pretreatment box body (111) through an injection port (133), and drying again until the auxiliary raw materials are dried, so that the auxiliary raw materials are uniformly distributed in the production process; S3, starting a heating coil on the surface of a blanking valve (114), increasing heating power of a heating plate (113) and a heating rod (136), and carrying out melting operation on PP particles and auxiliary raw materials to enable the PP particles and the auxiliary raw materials to be mixed with each other, so as to form PP particles in a molten state; S4, after melting, starting a blanking valve (114) to discharge PP particles in a molten state into a guide pipe (312) in a guide assembly (31), simultaneously starting an injection hydraulic cylinder (222) to drive an injection plug (223) to inject and press a foaming agent in a storage box (211), controlling the dosage of the foaming agent through a transparent plate (212) and a metering scale (213), and starting a first electromagnetic valve (32) and a second electromagnetic valve (33) to inject the PP particles in the molten state and the foaming agent into a Y-shaped pipe (342); S5, uniformly injecting PP particles in a molten state and foaming agents into a spiral pipe (42) of a mixing box body (41) through an air pump externally connected with a first connecting pipe (341) and a second connecting pipe (343), performing spiral mixing and transportation through the spiral pipe (42) until mixed materials are discharged into the top of a flow turbine (44), performing foaming operation at the lower end of the inside of the mixing box body (41), driving the flow turbine (44) to rotate through flowing generated by the foamed materials and expanding bubbles and materials generated after foaming, so that the flow turbine (44) continuously mixes and stirs the materials in the foaming state, fully mixing the foaming agents and the PP particles in the molten state, and discharging the mixed materials into granulating equipment (5) through a discharging groove at the bottom of a mixing bottom plate (43); S6, discharging the foaming material into the surface of a second granule groove (532) of a granulation lower die (531) through an inlet (512) of the introduction assembly (51) and a guide plate (513), filling the second granule groove (532), and enabling the granulation upper die (521) to continuously slide on the top surface of the granulation lower die (531) by starting an electric telescopic rod (525), so that the first granule groove (523) is matched with the second granule groove (532), and rolling and pressing the foaming material to roll the foaming material into foaming granules; S7, gradually increasing the foaming particles through molding, pushing the foaming particles into the particle outlet notch (533) through pushing by the baffle (524), discharging the foaming particles into the particle screening assembly (6) through the particle outlet notch (533), screening the foaming particles by the first screening plate (63), the second screening plate (64) and the third screening plate (65), discharging the qualified foaming particles out of the screening outlet (62) through the third screening plate (65), and dropping the unqualified foaming particles on the surface of the sealing plate (66) for temporary storage, thereby facilitating later cleaning.

Description

Foaming polypropylene particle production line and production method thereof Technical Field The invention relates to the technical field of polypropylene particle production, in particular to a foaming polypropylene particle production line and a production method thereof. Background The foamed polypropylene particle is a novel polymer material, is prepared from polypropylene serving as a main raw material through adding a foaming agent and other auxiliary agents and a special processing technology, has the excellent performances of light weight, heat insulation, sound insulation, shock resistance, impact resistance, easy processing and forming and the like, and is widely applied to the fields of packaging, heat preservation, sound insulation, filling and the like. The existing production methods of Expanded Polypropylene Particles (EPP) are mainly divided into two types: One is a batch autoclave process which is essentially the same as the process for preparing EPS beads, using polypropylene copolymers. The polymer is formed into small spherical particles during processing, and then added into a processing tank in the form of a mixture with water, and the polymer particles are immersed in a hydrocarbon foaming agent (such as propane) at high temperature and high pressure. After the hydrocarbon is fully absorbed, the pressure is reduced, the particles expand and form low-density beads with the diameter of about 4-5 mm, the beads contain foaming agent, the foaming agent can be recycled for further application, because the beads are small, the foaming agent which escapes from the particles when the polymer is below the melting temperature and above the glass transition temperature has high diffusion speed, and the foaming agent in the product can basically completely escape within a few days after production; And secondly, the extrusion continuous production method requires special processing equipment, such as a serial extrusion system or a co-rotating double-screw extruder, and a downstream charging barrel and a die of the extruder need to be specially designed to withstand the high pressure (15-20 MPa) of the foaming agent. However, both production modes need to pass through longer production process and production line equipment, so that a large number of production line equipment is needed when the expanded polypropylene particles are produced, and the rate of the expanded polypropylene particles is lower due to the longer production line, meanwhile, in the production of the expanded polypropylene particles, the high-elasticity temperature range of the expanded polypropylene particles is very narrow due to the high crystallinity of the polypropylene, so that the gas in the expansion process is difficult to be kept in a resin matrix, the expansion difficulty of the polypropylene particles is higher, and the performance of the expanded polypropylene particles is unstable. For this purpose, we propose a production line of expanded polypropylene particles and a production method thereof. Disclosure of Invention In order to solve the technical problems, according to one aspect of the present invention, the following technical solutions are provided: A expanded polypropylene particle production line comprising a particle screen assembly; a particle screening assembly placed on the ground with the particle screening assembly installed at the bottom of the granulating apparatus, and used for screening the foamed polypropylene particles to a particle size and discharging the particles conforming to the size at the same time; Further comprises: A pretreatment device installed and placed through a bracket at the top of the granulation device, and having the pretreatment device installed at the right end of the bracket, and being used for an integrated operation of drying, premixing and melting the PP particles through the pretreatment device; the foaming storage and metering device is arranged and placed through a bracket at the top of the granulating device, is arranged at the left end of the bracket, is used for storing foaming agent through the foaming storage and metering device, and is used for injecting and discharging the foaming agent according to a metering value through driving of the foaming storage and metering device; The top of the transportation device is provided with two ports, one port is connected to the bottom of the pretreatment equipment, the other port is connected to the bottom of the foaming storage and metering equipment, the bottom port of the transportation device is connected to the top of the mixing assembly, and the transportation device is externally connected with an air pump for transporting materials in the pretreatment equipment and the foaming storage and metering equipment simultaneously; The mixing component is arranged at the bottom of the conveying device, the bottom of the mixing component is arranged on the surface of the granulating device, the foaming agent and the PP p