CN208180198U - A kind of polyethylene/EVOH co-extrusion die - Google Patents

Abstract

The utility model discloses a kind of polyethylene/EVOH co-extrusion dies, belong to plates forming equipment field.Including the first die head and the mold monomers at the first die head rear are located at, mold monomers are successively arranged the first die body, supporting plate, transition plates, the first compression plate, the second compression plate and mouth template, and the second die head is equipped on the side wall of transition plates and the first compression plate；The first polyethylene runner and EVOH runner that first die head and the second die head are passed in and out with the cavity composition polyethylene and EVOH opened up in mold monomers respectively and being two layers, first polyethylene runner and EVOH runner independently and are respectively streamlined, gradually continuous reduce is transitioned into the river outlet being provided in mouth template, polyethylene and EVOH melt are after shunting and compression, it can be squeezed out from river outlet, row is at surface coextruded plastic parison, wherein the first polyethylene runner is laid in the internal layer of EVOH runner.The mold can make material be combined with each other in extrusion process, and melting interface is stable and uniform.

Description

A kind of polyethylene/EVOH co-extrusion die

Technical field

The utility model belongs to plates forming equipment field, and in particular to a kind of polyethylene/EVOH co-extrusion die.

Background technique

Modern plastics production of articles is gradually in progress to composite material direction from homogenous material, has evolved to so far Plastics and rubber, metal material, and timber, fiber, compound etc. with a variety of plastics such as inorganic material, composite forming technology is with its spy Some excellent properties are widely used in the industries such as building, automobile, electronics and furniture.

It is a kind of extrusion molding composite forming technology for starting application the 1980s that plastic co-extrusion, which goes out processing technology, it has claimed For one of the present age state-of-the-art plastics processing method.It is to be supplied respectively to difference using several extruders that plastic co-extrusion, which goes out technique, Melting stream, stream is compound in a composite machine head to converge coextrusion to obtaining multilayer composite product.It can make more There is layer the material of different characteristics to be combined with each other in extrusion process, and product is made to have the excellent spy of several different materials concurrently Property, characteristically carry out it is complementary, to obtain the performance and appearance of particular/special requirement, such as anti-oxidation, moisture-proof, humidity-preserving type, heat at Type and the heat bonding mechanical properties such as ability and intensity, rigidity, hardness.These multilayer materials with comprehensive performance are being permitted It is multi-field to have extremely wide application value.In addition, it can be greatly lowered goods cost, simple flow, reduce equipment throwing Money, recombination process does not have to solvent, therefore coextrusion technology has been used for laminated film, plate, tubing, profile shapes and wire and cable Production.

Multilayer composite board occupies an important position in co-extrusion modling, its application field is concentrated mainly on building wall board On decoration, multilayer composite board headed by plastic building template is integrated with the good characteristic of multiple polymers, so that altogether Extrusion board has more superiority on the basis of meeting basic mechanical performance.

Material is coextruded in extrusion process, due to the difference of every layer of material parameter and thickness, during coextrusion It will appear that muzzle velocity is uneven and interfacial Instability, this will directly affect the quality of product.

Utility model content

In order to overcome the problems of the above-mentioned prior art, the purpose of this utility model is to provide a kind of polyethylene/ EVOH co-extrusion die, this mold can make polyethylene/EVOH material be combined with each other in extrusion process, merge boundary Face is stable and uniform.

The utility model is to be achieved through the following technical solutions:

A kind of polyethylene/EVOH co-extrusion die including the first die head and is located at the mold monomers at the first die head rear, mould Tool monomer is successively arranged the first die body, supporting plate, transition plates, the first compression plate, the second compression plate and mouth template, in transition plates and The side wall of first compression plate is equipped with the second die head；

First die head and the second die head constituted respectively with the cavity opened up in mold monomers polyethylene and EVOH disengaging and It is two layers of the first polyethylene runner and EVOH runner, the first polyethylene runner and EVOH runner independently and are respectively streamline Type, gradually continuous reduce is transitioned into the river outlet being provided in mouth template, polyethylene and EVOH melt after shunting and compression, It can be squeezed out from river outlet, row is at surface coextruded plastic parison, wherein the first polyethylene runner is laid in the internal layer of EVOH runner.

Preferably, river outlet is 60mm at a distance from the second compression plate.

Preferably, third die head is additionally provided in transition plates and the first compression plate side wall, wherein third die head and the second mould Head is oppositely arranged；The cavity opened up in third die head and mold monomers constitutes the second poly- second that is polyethylene disengaging and being two layers Alkene runner, the second polyethylene runner it is respectively independent and be it is streamlined, gradually continuous reduce is transitioned into the remittance being provided in mouth template At stream, polyethylene melt can squeeze out after shunting and compression from river outlet, and row is at surface coextruded plastic parison.

It is further preferred that the surface roughness of EVOH runner, the first polyethylene runner and the second polyethylene runner is less than 0.2um。

Preferably, the polyethylene in the first polyethylene runner is high density polyethylene (HDPE), the poly- second in the second polyethylene runner Alkene is low density polyethylene (LDPE).

Preferably, it is respectively arranged with and the first die head, the second die head and third die head in supporting plate and in the first compression plate Spreader connected and that material can be uniformly divided into two layers, spreader are flowed with corresponding first polyethylene runner, EVOH respectively Road and the connection of the second polyethylene runner.

Preferably, EVOH runner is located at the first polyethylene runner and the second polyethylene runner, and the first polyethylene runner and Second polyethylene runner is laid staggeredly.

Preferably, EVOH runner is successively provided on transition plates, the first compression plate, the second compression plate and mouth template；First Polyethylene runner and the second polyethylene runner are provided on the first compression plate, the second compression plate and mouth template.

Compared with prior art, the utility model has technical effect beneficial below:

The utility model discloses a kind of polyethylene/EVOH co-extrusion dies, are flowed by the first polyethylene runner and EVOH Road, and each runner it is respectively independent and be it is streamlined, gradually continuously reduce transition river outlet, ensure that charging melt flow rate Uniformity, melt In-mold residence times are long, soffening is good, squeeze out stablize, each layer uniform feeding, wall thickness are consistent, are convenient for Adjustment guarantees board quality, overcomes and deform between layers, and flow passage design has the comprehensive mechanical property of plate very Big raising, the first polyethylene runner and EVOH runner are two layers, be conducive to production four layers of uniform plate composite material, first Polyethylene runner is laid in the outer layer of EVOH runner, to have fabulous barrier property and fabulous processability to gas, while interior The polyethylene of recycling can be used in layer, reduces cost of material, greatly enhances the practicability of coextrusion plate.

Further, river outlet is 60mm at a distance from the second compression plate, can effectively be compensated because die swelling is imitated Answer generated influence.

Further, by with three die heads respectively with EVOH runner, the second polyethylene runner and the second polyethylene runner Connection, is easy to implement and connect with extruder, produces six layers of uniform plate composite material.

Further, the surface roughness of the first polyethylene runner, EVOH runner and the second polyethylene runner is less than 0.2um；Further, the mold cavity surface roughness of runner is 0.1um, and runner is smooth not to generate retardance to material, is conducive to Material Uniform Flow.

Further, the polyethylene in the first polyethylene runner is high density polyethylene (HDPE), poly- in the second polyethylene runner Ethylene is low density polyethylene (LDPE), conducive to the plate of three kinds of monomer materials of production.

Further, by spreader, convenient for material is uniformly divided into two layers.

Further, EVOH runner is located at the outside of the first polyethylene runner and the second polyethylene runner, and the first poly- second Alkene runner and the second polyethylene runner are laid staggeredly, and six layers easy to produce uniform plate composite material, EVOH is located at outer layer, from And there is fabulous barrier property and fabulous processability to gas, while internal layer can be used the polyethylene of recycling, reduce raw material at This, greatly enhances the practicability of coextrusion plate.

Detailed description of the invention

Fig. 1 is the structural schematic diagram of the utility model；

Fig. 2 is sectional view of the Fig. 1 along the direction B-B；

Fig. 3 is sectional view of the Fig. 1 along the direction A-A；

Fig. 4 is the sectional view of the EVOH runner of the utility model, the first polyethylene runner and the second polyethylene runner；

Fig. 5 is the plate figure of the utility model production；

Fig. 6 is sectional view of the Fig. 5 along the direction A-A；

Fig. 7 and Fig. 8 is the explosive view of the utility model.

Wherein: 1 is the first die head；2 be the second die head；3 be third die head；4 be the first screw；5 be straight pin；6 be Two screws；7 be ring flange；8 be the first die body；9 be supporting plate；10 be transition plates；11 be the first compression plate；12 be the second compression Plate；13 be mouth template；14 be river outlet；15 be EVOH runner；16 be the second polyethylene runner；17 be the second polyethylene runner.

Specific embodiment

1~8 pair of the utility model is described in further detail with reference to the accompanying drawing:

Referring to Fig. 1, Fig. 3, Fig. 7 and Fig. 8, a kind of polyethylene/EVOH co-extrusion die, including the first die head 1 and it is located at The mold monomers at one die head, 1 rear, mold monomers are successively arranged the first die body 8, supporting plate 9, transition plates 10, the first compression plate 11, the second compression plate 12 and mouth template 13 are equipped with the second die head 2 on the side wall of transition plates 10 and the first compression plate 11；First Die head 1 and the second die head 2 constituted respectively with the cavity opened up in mold monomers polyethylene and EVOH disengaging and be two layers First polyethylene runner 16 and EVOH runner 15, the first polyethylene runner 16 and EVOH runner 15 it is respectively independent and be it is streamlined, Gradually continuous reduce is transitioned into the river outlet 14 being provided in mouth template (13), and then is transitioned into required contoured cross-section shape Shape, polyethylene and EVOH melt can squeeze out after shunting and compression from river outlet 14, and row is at surface coextruded plastic parison, most After being formed by supercooling, four layers of composite board by EVOH together with both Material claddings of polyethylene are formed, wherein the One polyethylene runner 16 is laid in the internal layer of EVOH runner 15.Lead to respectively independent and be streamlined, the runner gradually continuously reduced, Ensure that charging melt flow rate uniformity, melt In-mold residence times are long, soffening is good, squeeze out stablize, each layer Uniform feeding, wall thickness are consistent, are conveniently adjusted, and guarantee board quality, overcome and deform between layers, and flow passage design makes The comprehensive mechanical property of plate improves a lot, and the first polyethylene runner 16 is laid in the internal layer of EVOH runner 15, is convenient for EVOH material is in the outer layer of plate, to have fabulous barrier property and fabulous processability to gas, the polyethylene of internal layer has Have the advantages that nontoxic, surface is smooth, smooth, corrosion-resistant, electrical insulation capability is excellent, low temperature performance well, is widely used in chemical industry, electric power etc. Industrially, while the polyethylene of recycling can be used in internal layer, reduces cost of material, greatly enhances coextrusion plate Practicability.Due to the melt variation of stress state afterwards before the forming, die swelling effect can be caused, make plastic Length Contraction and cut Face geomery changes, when river outlet 14 at a distance from the second compression plate 12 be 60mm, can effectively compensate because from It is influenced caused by mould bulking effect.

Referring to Fig. 1~4,7 and 8, third die head 3 is additionally provided on 11 side wall of transition plates 10 and the first compression plate, wherein the Three die heads 3 are oppositely arranged with the second die head 2；The cavity opened up in third die head 3 and mold monomers constitute polyethylene disengaging and Be two layers of the second polyethylene runner 17, the second polyethylene runner 17 it is respectively independent and be it is streamlined, gradually continuously reduced It crossing to the river outlet 14 being provided in mouth template 13, the polyethylene in the first polyethylene runner 16 is high density polyethylene (HDPE), second Polyethylene in polyethylene runner 17 is low density polyethylene (LDPE), and high density polyethylene (HDPE), low density polyethylene (LDPE) and EVOH melt pass through Shunt and compression after, can be squeezed out from river outlet 14, row at surface coextruded plastic parison, finally after cooling and shaping, formation by Six layers of composite board together with these three Material claddings of EVOH, high density polyethylene (HDPE) and low density polyethylene (LDPE), six layers of composite plate Material is with a thickness of 12mm.Since polyethylene has, nontoxic, surface is smooth, smooth, corrosion-resistant, electrical insulation capability is excellent, low temperature performance well The advantages that, it is widely used in chemical industry, electric power etc. industrially, EVOH material is fabulous to have to gas in the outer layer of polythene material Barrier property and fabulous processability；HDPE (high density polyethylene (HDPE)) is alternatively arranged as engineering plastics and applies in equipment such as machinery, chemical industry On, the thickness of this layer is generally 1~2mm.The EVOH inlet of first die head 1 is connected by ring flange 7 with extruder, and second The inlet of the low density polyethylene (LDPE) of the high density polyethylene (HDPE) and third die head 3 of die head 2 equally passes through ring flange 7 and other two Extruder is connected, and three extruders are achieved while being fed, wherein ring flange 7 is fixed by the second screw 6.

Referring to fig. 2,3,7 and 8, it is respectively arranged with and the first die head 1, the second mould in supporting plate 9 and in the first compression plate 11 First 2 spreaders be connected with third die head 3 and that material can be uniformly divided into two layers, spreader respectively with corresponding first poly- second Alkene runner 16, EVOH runner 15 and the connection of the second polyethylene runner 17；Convenient for material is uniformly divided into two layers.

Referring to fig. 2, Fig. 7 and Fig. 8, the first die body 8, supporting plate 9, transition plates 10, the first compression plate 11, the second compression plate 12 It is fixed by the positioning of straight pin 5, the first screw 4 between 13 adjacent panels of mouth template.First die body 8, supporting plate 9, transition plates 10, the junction of 13 adjacent panels of the first compression plate 11, the second compression plate 12 and mouth template offers opening slot；Conducive to disassembly and Assembly, and the side of each plate is also provided with thermometer hole and heating plate mounting hole；To be supervised to the temperature of solution in runner It surveys and adjusts.The threaded hole for connecting with hanging ring is offered on die head or on ring flange 7, convenient for the co-extrusion die and is squeezed Machine connects out.Wherein, the first die body 8 and compression plate 2 are processed using low-speed WEDM, supporting plate 9, transition plates 10, compression The cavity (forming EVOH runner 15, the second polyethylene runner 16 and the second polyethylene runner 17) that plate 1 and mouth template 13 open up is adopted With Cutter Body Processing with Machining Center, surface polishing is to squeeze based on hone machine, EVOH runner 15, the second polyethylene runner 16 and the second poly- second The mold cavity surface roughness of alkene runner 17 are as follows: Ra0.1um；Each die plate connecting hole is processed using numerical control drilling machine, when fitter assembly, The alignment of type chamber, gap is uniform, and size meets drawing requirement, smoothly transits, matches pin (positioning of straight pin 5) to contact runner, the The fastening of one screw 4.By the utility model, the effect of high density polyethylene (HDPE), low density polyethylene (LDPE) and the EVOH of melting in pressure Down by respective runner, after shunting and compression, squeezed out at mouth mold version slit, row is at surface coextruded plastic parison, most After being formed by supercooling, composite board shown in Figures 5 and 6 is formed.

The experimental requirement of the utility model determines parameter: primarily determining entrance according to the empirical equation of extrusion board Radius, fan section the angle (angle of spreader and entrance when material enters co-extrusion die from extruder in three Degree), adjust the length of part, the height and length in die lip area.Then analysis is optimized by simulation software, checks mouth mold Plate outlet flow everywhere whether balance, speed it is whether consistent, otherwise to adjust the structural parameters of mold, guarantee that mouth template outlet is each The pressure and muzzle velocity at place is consistent and interface stability, squeezes out melt uniformly.Polyethylene can be used in outer layer and internal layer Raw material perhaps preferable reclaimed materials and middle layer charging can by rational proportion add or use recycle polyethylene material, section Cost has been saved it is also ensured that meeting sheet mechanical property.

In order to obtain good plastic sheet product, EVOH runner 15, the second polyethylene runner 16 and the second polyethylene stream Road 17 gradually should continuously reduce, and be transitioned into required contoured cross-section shape, to meet the requirement of people.Consider simultaneously The pressure of extrusion die is acted in extrusion molding to sheet plastics, damages extrusion die mouth mold.Therefore head will close Reduce the length of mouth mold under suitable compression ratio and in the case where guaranteeing that stream is stablized to the greatest extent, and the heating of reasonable Arrangement head is cold But device keeps its heating cooling velocity fast, meets production requirement, and it is in streamline that precision is high, and material flow path is answered smooth in extrusion head Type, cannot there is the position of retardance, and mold cavity surface roughness should be less than 0.2um；Secondly as melt before the forming after stress state Variation, die swelling effect can be caused, plastic Length Contraction and cross sectional shape size is made to change, therefore, design squeeze Out it is noted that this point, will carry out compensation appropriate, to guarantee that extruded product has correct cross sectional shape and ruler when die head It is very little, obtain the plastic sheet for meeting production requirement.

Outer layer and intermediate runner independent are capable of forming by the utility model.It ensure that charging melt flows speed Spend uniformity, melt In-mold residence times it is long, be heated evenly, soffening it is good, squeeze out stablize, each layer uniform feeding, wall Thickness is consistent, is conveniently adjusted, and guarantees board quality.It overcomes and deforms between layers, and reasonable extrusion channel makes plate Comprehensive mechanical property improves a lot；The polyethylene of recycling can be used in middle layer, reduces cost of material, largely mentions The high practicability of coextrusion plate.

The above is only the preferred embodiment of the utility model only, is not intended to limit the utility model, all in reality Within novel spirit and principle, any modification, equivalent replacement, improvement and so on should be included in the use of the new type Within protection scope.

Claims (8)

1. a kind of polyethylene/EVOH co-extrusion die, which is characterized in that including the first die head (1) and after being located at the first die head (1) Side mold monomers, mold monomers be successively arranged the first die body (8), supporting plate (9), transition plates (10), the first compression plate (11), Second compression plate (12) and mouth template (13) are equipped with the second die head on the side wall of transition plates (10) and the first compression plate (11) (2)；

What the first die head (1) and the second die head (2) were passed in and out with the cavity composition polyethylene and EVOH opened up in mold monomers respectively It and is two layers of the first polyethylene runner (16) and EVOH runner (15), the first polyethylene runner (16) and EVOH runner (15) It is respectively independent and be it is streamlined, gradually continuous reduce is transitioned into the river outlet (14) being provided in mouth template (13), polyethylene and EVOH melt can squeeze out after shunting and compression from river outlet (14), and row is at surface coextruded plastic parison, wherein first is poly- Ethylene runner (16) is laid in the internal layer of EVOH runner (15).

2. polyethylene according to claim 1/EVOH co-extrusion die, which is characterized in that river outlet (14) and the second pressure The distance of contracting plate (12) is 60mm.

3. polyethylene according to claim 1/EVOH co-extrusion die, which is characterized in that in transition plates (10) and first Third die head (3) are additionally provided on compression plate (11) side wall, wherein third die head (3) is oppositely arranged with the second die head (2)；Third The cavity opened up in die head (3) and mold monomers constitutes the second polyethylene runner (17) that is polyethylene disengaging and being two layers, Second polyethylene runner (17) it is respectively independent and be it is streamlined, gradually continuous reduce is transitioned into the remittance being provided in mouth template (13) At stream (14), polyethylene melt can squeeze out after shunting and compression from river outlet (14), and row is at surface coextruded plastic parison.

4. polyethylene according to claim 3/EVOH co-extrusion die, which is characterized in that EVOH runner (15), first gather The surface roughness of ethylene runner (16) and the second polyethylene runner (17) is less than 0.2 μm.

5. polyethylene according to claim 3/EVOH co-extrusion die, which is characterized in that the first polyethylene runner (16) Interior polyethylene is high density polyethylene (HDPE), and the polyethylene in the second polyethylene runner (17) is low density polyethylene (LDPE).

6. polyethylene according to claim 3/EVOH co-extrusion die, which is characterized in that pressed in supporting plate (9) with first It is respectively arranged in contracting plate (11) being connected with the first die head (1), the second die head (2) and third die head (3) and can be equal by material The even spreader for being divided into two layers, spreader are poly- with corresponding first polyethylene runner (16), EVOH runner (15) and second respectively Ethylene runner (17) connection.

7. polyethylene according to claim 3/EVOH co-extrusion die, which is characterized in that EVOH runner (15) is located at the The outside of one polyethylene runner (16) and the second polyethylene runner (17), and the first polyethylene runner (16) and the second polyethylene stream Road (17) is laid staggeredly.

8. polyethylene according to claim 3/EVOH co-extrusion die, which is characterized in that EVOH runner (15) is successively opened It is located on transition plates (10), the first compression plate (11), the second compression plate (12) and mouth template (13)；First polyethylene runner (16) It is provided on the first compression plate (11), the second compression plate (12) and mouth template (13) with the second polyethylene runner (17).