Production method and production device of composite two-way stretching plastic geogrid

Abstract

The invention provides a production method and a production device of a composite two-way stretching plastic geogrid, and particularly relates to the technical field of geogrid production, and the production method specifically comprises the following steps: carrying out plate extrusion operation by using two different extruders; a compounding device is used for performing compounding operation on a plurality of plates; punching operation is conducted on the plate through punching equipment; and a longitudinal stretcher and a transverse stretcher are used for carrying out two-way stretching operation on the plate. According to the production method and the production device of the composite two-way stretching plastic geogrid, the mechanical performance and the production efficiency of a two-way stretching plastic geogrid plate can be improved, the overall strength is improved through the additive adding and electric field treatment process, punching and demolding are facilitated, and the production efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of geogrid production, and in particular to a production method and a production device of a composite biaxially stretched plastic geogrid. Background Art

[0002] As a commonly used material in geotechnical engineering, geogrid plays an important role in the reinforcement and protection of roads, dams, slopes and other projects. Traditional geogrid production methods can usually only produce products of a single material and color, which is difficult to meet the needs of different projects for the diversified performance of geogrids. For example, in some special engineering environments with high requirements for corrosion resistance and strength, geogrids made of a single material cannot meet the high performance requirements of both. Therefore, it is of great significance to develop a method and device for producing geogrids with multiple composite materials, diverse colors and superior performance.

[0003] However, there are still several technical problems when multiple materials are composited and processed:

[0004] (1) In the process of forming the geogrid, a punching needle is set on the upper die, and a hole corresponding to the punching needle is set on the lower die. The upper die is pressed down by a pressure device to punch holes through the plastic geogrid placed between the upper and lower dies, so as to achieve punching and cutting operations on thinner plastic geogrids. However, in the actual punching operation, because the thickness of the plastic geogrid used is relatively thin, after the upper and lower dies are combined to punch holes, the punching needle and the plastic geogrid are not easy to withdraw due to the large surface friction resistance, that is, the punching needle is not easy to fall off the geogrid and the punching needle. If it is taken manually, there are disadvantages of low efficiency and easy bending of the geogrid surface;

[0005] (2) The bidirectional integral tensile grid has excellent reinforcement performance, but its current maximum strength is 50 kN / m, which does not meet the requirements of special projects for high-strength bidirectional grids;

[0006] (3) When the longitudinal and transverse strengths of geogrid products are equal, it does not meet the requirements of special projects for high strength in the main force direction of the product and low strength in the other direction; when the longitudinal strength and transverse strength of geogrid products are different, it does not meet the requirements of some projects for transverse strength. For example, if this one-way grid is used in road projects, the stability of deep sliding of the slope can be guaranteed. However, since the strength of the grid along the road is very low, it basically does not play a role in restraining the deformation of the roadbed fill in this direction. Therefore, how to adaptively adjust the longitudinal and transverse strengths according to the actual situation has become the key technical problem to be solved in this plan.

[0007] Therefore, the present invention provides a production method and a production device of a composite biaxially stretched plastic geogrid, which are used to solve the above-mentioned technical problems at the same time. Summary of the invention

[0008] The purpose of the present invention is to provide a production method and a production device for a composite biaxially oriented plastic geogrid, which solves the technical problem of how to improve the mechanical properties and production efficiency of biaxially oriented plastic geogrid plates. By adding additives and electric field treatment technology, the overall strength is improved, and it also helps with punching and demolding, thereby improving production efficiency.

[0009] A method for producing a composite biaxially stretched plastic geogrid, comprising the following steps:

[0010] Step S1: using two different extruders to perform sheet extrusion operations;

[0011] Step S2: using a compounding device to perform a compounding operation on a plurality of plates;

[0012] Step S3: using a punching device to perform a plate punching operation;

[0013] Step S4: using a longitudinal stretching machine and a transverse stretching machine to perform biaxial stretching operation on the sheet.

[0014] In the step S1, polypropylene raw material, graphene, and polytetrafluoroethylene are added to one of the extruders, and polyethylene raw material, polyimide, molybdenum disulfide, and glass fiber are added to the other extruder;

[0015] Among them, by mass, polypropylene raw materials: graphene: polytetrafluoroethylene = (10-15): (1.0-2.4): (0.5-1.5), polyethylene raw materials: polyimide: molybdenum disulfide: glass fiber = (8-12): (0.5-1.0): (1.0-1.5): (1.0-4.0).

[0016] In terms of mass, (graphene + glass fiber) / (polytetrafluoroethylene + molybdenum disulfide) = 1.0-4.0.

[0017] In step S1, the extruder is connected to the material hopper, the material is added to the material hopper, the extruder is turned on, and the temperature parameters of each extruder are set so that the material is gradually melted and plasticized in the heating zone under the rotation of the screw, and different die heads are designed to extrude and form plates of different thicknesses and widths. Among them, the connection method of the screw, the heating zone and the die head is the prior art and will not be described in detail here.

[0018] For example, for the extrusion of polypropylene (PP) material, the temperature is controlled at 180-220°C, and the screw speed is adjusted according to the sheet thickness and extrusion volume.

[0019] More preferably, masterbatch can be mixed into polyethylene raw materials or polypropylene raw materials to help form sheets of different colors. The composite sheets of different colors can also give the product identification function; the content of masterbatch can be adjusted according to actual circumstances.

[0020] In step S2, the extruded different sheets are transported to a composite device, which preheats the sheets to make the surface temperature of the sheets reach a range suitable for composite, and then closely fits the sheets under a certain pressure for a holding time t to fully fuse the sheets;

[0021] The composite temperature can be controlled at 150-180°C, the pressure can be set at 5-10MPa, and the holding time can be 3-5 minutes.

[0022] In step S3, the composite whole plate enters the punching process, and the punching equipment is used to perform the punching operation according to the hole diameter and hole spacing designed for the geogrid.

[0023] When punching, the punch stroke and blanking force are precisely controlled to ensure that the punched holes have regular shapes and accurate sizes, while the waste generated by punching is collected and processed in a timely manner.

[0024] In step S4, the punched sheet is biaxially stretched, and power is applied during the stretching process; the sheet is first stretched in the longitudinal direction on the longitudinal stretching machine using a longitudinal stretching machine and a transverse stretching machine; the stretching multiple is set according to the product performance requirements, generally 3-5 times. The longitudinally stretched sheet then enters the transverse stretching machine and is stretched perpendicular to the length direction, and the transverse stretching multiple matches the longitudinal stretching multiple to ensure that the mechanical properties of the grid are uniform in both directions;

[0025] During the stretching process, the stretching temperature is controlled at 110-130°C, and the stretching speed is adjusted according to the thickness and material of the plate.

[0026] A production device for a composite biaxially stretched plastic geogrid comprises a material hopper and an extruder unit connected in sequence, a plurality of supporting and transmitting structures for receiving and transmitting a plurality of plates respectively, a composite device for compositely extruding a plurality of plates, a punching device for punching the composite plates, and a biaxially stretching device for longitudinally and transversely stretching the punched plates, wherein the plurality of supporting and transmitting structures are arranged in parallel up and down.

[0027] The extruder group includes a plurality of extruders, and the extruders include a screw structure, a heating zone, and a die head for extrusion molding which are connected in sequence.

[0028] The composite device comprises a preheating unit, a pressure applying unit and a pressure maintaining unit which are connected in sequence, and one end of the supporting transmission structure is arranged close to the preheating unit.

[0029] The supporting transmission structure comprises a crossbar 1 and a crossbar 2 arranged in parallel with each other, and a rotating rod structure connected to the crossbar 1, wherein the rotating rod structure is in separate contact with the crossbar 2, and an extruded plate is arranged between the crossbar 1 and the crossbar 2, and the extruded plate is movably mounted on the rotating rod structure;

[0030] The upper end surface of the cross bar 1 is provided with an opening groove 1, and the upper end surface of the cross bar 2 is provided with an opening groove 2, wherein the upper rotating rod structure is in separate contact with the opening groove 1 and the opening groove 2 on the lower rotating rod structure.

[0031] The rotating rod structure includes a rotating block and a positioning block respectively arranged near the cross bar 1 and the cross bar 2, an upper rotating column and a lower rotating column respectively connected to the rotating block and the positioning block at both ends, a gear 1 coaxially connected to one end of the upper rotating column, a gear 2 coaxially connected to one end of the lower rotating column, and a driving motor drivingly connected to the other end of the lower rotating column, the upper rotating column and the lower rotating column are arranged parallel to each other, the gear 1 and the gear 2 are meshed and connected with each other, and a baffle is arranged at the bottom end of the rotating block;

[0032] The rotating block is fixedly connected to a vertically arranged power shaft, the power shaft is rotatably connected to a fixed seat, the fixed seat is fixed on the outer side of the crossbar 1, and the power shaft is connected to a micro motor;

[0033] The outer sides of the cross bar 1 and the cross bar 2 are respectively fixedly connected with fixing columns, and the fixing columns are connected to the lifting mechanism.

[0034] More preferably, the lifting mechanism is connected to the moving mechanism, and the moving mechanism drives the lifting mechanism and the rotating rod structure to move to the inside of the composite device, thereby achieving a transfer effect.

[0035] The preheating unit preheats the different plates delivered, the pressure applying unit applies a certain pressure to the plates after preheating to make them fit together, and the pressure holding unit maintains the pressure for a period of time to ensure that the plates are fully fused.

[0036] The punching equipment comprises a special punch, a die arranged below the special punch, and a control system for controlling the punch stroke and the punching force, and is used for punching the composite sheet.

[0037] The biaxial stretching equipment includes a longitudinal stretching machine and a transverse stretching machine, which respectively perform longitudinal and transverse stretching on the punched sheet material. The longitudinal stretching machine and the transverse stretching machine are both equipped with a temperature controller, a speed controller and a stretching multiple controller.

[0038] The positive effects of the present invention are as follows:

[0039] (1) Adding polyimide and molybdenum disulfide to form a nanocomposite material close to a nano-dispersed inorganic polymer system can effectively reduce the friction coefficient of polyimide, and the friction coefficient of polyimide decreases with the increase of molybdenum disulfide content;

[0040] MoS2 and graphene work together to synthesize a three-dimensional oxygen-doped MoS2-rGO composite at high temperature. The addition of graphene can significantly improve the electrochemical properties of MoS2.

[0041] In addition, graphene can prevent the stacking of MoS2 nanosheets, exposing more active centers and further improving the electrocatalytic performance;

[0042] (2) Adding polytetrafluoroethylene and graphene, the combination of the two can greatly reduce the friction coefficient of the geogrid; polytetrafluoroethylene and graphene can flocculate through electrostatic adsorption, and after chemical reduction, a PTFE / graphene nanocomposite material can be obtained. The composite material exhibits a high tensile modulus, yield strength and electrical conductivity;

[0043] (3) Adding glass fiber achieves the following technical effects:

[0044] First, glass fiber reinforcement increases the strength of the geogrid, but its friction coefficient is relatively large. By designing the ratio of glass fiber to materials such as graphene, a balance is achieved between easy demoulding and improved overall strength.

[0045] Second, adding glass fiber to cooperate with polytetrafluoroethylene and molybdenum disulfide effectively reduces the friction coefficient between the geogrid and the metal, making demoulding easier;

[0046] (4) When biaxially stretched, an electric field is applied, and graphene has a conductive effect. Graphene will undergo electrostriction. Applying an electric field in different directions (lateral and longitudinal) makes it easy to deform in one direction, which is not only conducive to tensile deformation, but also helps to achieve isotropy or anisotropy of the geogrid.

[0047] (5) The multiple extruders and die heads designed in this scheme can extrude different materials respectively, so that multiple materials can be compounded in the same product to meet the special requirements of different projects for geogrid performance;

[0048] The composite of different materials combines the advantages of each material, such as the combination of high strength and high flexibility, good corrosion resistance and anti-aging performance, etc., to improve the overall performance of the geogrid; the various layers of materials work together during punching and stretching of the composite plate to form a more stable grid structure, further enhancing the mechanical properties;

[0049] The extruder material formula and die parameters can be quickly adjusted according to market demand and customer orders to produce geogrid products of different specifications and material combinations. Compared with traditional production methods, it has stronger adaptability and can better meet the diversified needs of the market;

[0050] (6) In the prior art, when extruding sheets from the extruder to the composite device, a robot is required to arrange and place multiple extruded sheets up and down, which is inconvenient to operate. In this solution, a supporting transmission structure is designed, which has the following technical effects:

[0051] First, the upper rotating column is supported under the extruded sheet, and under the action of the driving motor, it plays a role of supporting transmission, which helps to transfer the extruded sheet from the extruder position to the compound device position;

[0052] Second, under the action of the micromotor, the upper rotating column and the lower rotating column are simultaneously rotated 90° to the bottom of the crossbar 1, so that the upper rotating column, the lower rotating column and the crossbar 1 are parallel to each other, so that the extruded sheets arranged up and down fall onto the support platform of the composite device, which is helpful for the subsequent pressurization and pressure holding process;

[0053] Third, under the action of the baffle under the rotating block and the swing of the positioning block, it helps to make the outer sides of multiple extruded plates flush and achieve the effect of straightening. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 The structure diagram of the supporting transmission structure in Embodiment 3 of the present invention is shown in FIG. Figure 1 .

[0055] Figure 2 The structure diagram of the supporting transmission structure in Embodiment 3 of the present invention is shown in FIG. Figure 2 .

[0056] Figure 3 Schematic diagram of the structure of the rotating rod in Example 3 of the present invention.

[0057] Figure 4 This is a schematic diagram of the working status of multiple supporting transmission structures in Example 3 of the present invention.

[0058] Figure 5 This is a bottom schematic diagram of the supporting transmission structure in Example 3 of the present invention.

[0059] Among them, the accompanying drawings are marked as: 1, cross bar one; 11, open slot one; 2, extruded plate; 3, fixed column; 4, cross bar two; 41, open slot two; 5, micro motor; 51, fixed seat; 6, rotating block; 7, rotating rod structure; 71, gear one; 72, gear two; 73, lower rotating column; 74, positioning block; 75, driving motor; 76, upper rotating column; 8, baffle. DETAILED DESCRIPTION

[0060] In order to more clearly illustrate the technical features of this solution, this solution is described below through specific implementation methods.

[0061] Example 1

[0062] A method for producing a composite biaxially stretched plastic geogrid, comprising the following steps:

[0063] Step S1: using two different extruders to perform sheet extrusion operations;

[0064] Step S2: using a compounding device to perform a compounding operation on a plurality of plates;

[0065] Step S3: using a punching device to perform a plate punching operation;

[0066] Step S4: using a longitudinal stretching machine and a transverse stretching machine to perform biaxial stretching operation on the sheet.

[0067] In step S1, polypropylene raw material, graphene, and polytetrafluoroethylene are added to one of the extruders, and polyethylene raw material, polyimide, molybdenum disulfide, and glass fiber are added to the other extruder;

[0068] Among them, by mass, polypropylene raw materials: graphene: polytetrafluoroethylene = (10-15): (1.0-2.4): (0.5-1.5), polyethylene raw materials: polyimide: molybdenum disulfide: glass fiber = (8-12): (0.5-1.0): (1.0-1.5): (1.0-4.0).

[0069] In step S1, the extruder is connected to the material hopper, the extruder is turned on, and the temperature parameters of each extruder are set so that the material is gradually melted and plasticized in the heating zone under the rotation of the screw. By designing different heads, the material is extruded into plates of different thicknesses and widths.

[0070] For example, for the extrusion of polypropylene and polyethylene, the temperature is controlled at 200°C and 190°C, respectively, and the screw speed is adjusted according to the sheet thickness and extrusion volume.

[0071] In step S2, the extruded different sheets are conveyed to a composite device, which preheats the sheets to make the surface temperature of the sheets reach a range suitable for composite, and then closely fits the sheets under a certain pressure for a holding time t to fully fuse the sheets;

[0072] Among them, the composite temperature can be controlled at 160°C, the pressure is set to 8MPa, and the holding time is 4 minutes.

[0073] In step S3, the composite whole plate enters the punching process, and the punching equipment is used to perform the punching operation according to the hole diameter and hole spacing designed for the geogrid.

[0074] When punching, the punch stroke and blanking force are precisely controlled to ensure that the punched holes have regular shapes and accurate sizes, while the waste generated by punching is collected and processed in a timely manner.

[0075] In step S4, the punched sheet is biaxially stretched and powered on at the same time. The power-on direction can be adjusted to horizontal or vertical. The sheet is first stretched in the longitudinal direction on the longitudinal stretching machine using a longitudinal stretching machine and a transverse stretching machine. The stretching multiple is set according to the product performance requirements and is set at 3 times. The longitudinally stretched sheet then enters the transverse stretching machine and is stretched perpendicular to the length direction. The transverse stretching multiple matches the longitudinal stretching multiple to ensure that the mechanical properties of the grid are uniform in both directions, and it is also convenient to calculate the mechanical properties of the power-on. During the stretching process, the stretching temperature is controlled at 115°C, and the stretching speed is adjusted with the sheet thickness and material.

[0076] In this plan, a control group, group A, group B, and group C were designed, and their tensile strength MD, tensile strength TD, elongation at break retention rate, and friction coefficient with metal were tested for comparison.

[0077] Among them, the control group: 10kg of polypropylene raw material, 10kg of polyethylene raw material;

[0078] Group A: 10kg polypropylene raw material, 1.0kg graphene, 0.5kg polytetrafluoroethylene; 10kg polyethylene raw material, 0.5kg polyimide, 1.0kg molybdenum disulfide, 1.0kg glass fiber;

[0079] Group B: 10kg polypropylene raw material, 1.5kg graphene, 0.8kg polytetrafluoroethylene; 10kg polyethylene raw material, 0.8kg polyimide, 1.2kg molybdenum disulfide, 2.0kg glass fiber;

[0080] Group C: 10kg of polypropylene raw material, 2.4kg of graphene, 1.5kg of polytetrafluoroethylene; 10kg of polyethylene raw material, 1.0kg of polyimide, 1.5kg of molybdenum disulfide, and 4.0kg of glass fiber.

[0081] Table 1 is a performance table of the plastic geogrid under each component in Example 1.

[0082] Table 1 Performance of plastic geogrids under various components in Example 1

[0083] sample Longitudinal tensile strength / kN / m Transverse tensile strength / kN / m Retention rate of elongation at break MD% Punching dynamic friction coefficient Control group 30 30 16 0.25 Group A 32 33 18 0.16 Group B 36 36.5 19 0.12 Group C 40.5 40 19.5 0.11 Group C Electric Field Treatment 43 41 21 0.10

[0084] From the above table, it can be roughly analyzed qualitatively that after adding graphene, polytetrafluoroethylene, polyimide, molybdenum disulfide and glass fiber, the tensile strength MD, tensile strength TD, elongation at break retention rate and friction coefficient with metal of the geogrid will be significantly improved; from the control group to group C, the increase in the punching dynamic friction coefficient is getting smaller and smaller. The reason is that in group C, the mass of glass fiber increases greatly, which makes the change value of the punching dynamic friction coefficient not large; in terms of its transverse and longitudinal tensile strength, the transverse and longitudinal tensile strengths of the control group are roughly equal, in groups A and B, the transverse tensile strength is larger, and in group C, the longitudinal tensile strength is larger. By analyzing the changes in their content, it can be seen that the changes in graphene, molybdenum disulfide, glass fiber and polytetrafluoroethylene are slightly larger, which indicates that the interaction between the four may help to regulate the transverse and longitudinal tensile strengths. The specific regulation ratio and action relationship still require a large number of experiments for further verification.

[0085] Finally, by performing electric field treatment on both the transverse and longitudinal directions of group C, it can be seen that the longitudinal tensile strength is significantly higher than the transverse tensile strength, the retention rate of elongation at break is greatly improved, and the friction coefficient with the metal is slightly reduced, which indicates that electric field treatment is effective in regulating tensile properties.

[0086] Example 2

[0087] In terms of mass, (graphene + glass fiber) / (polytetrafluoroethylene + molybdenum disulfide) = 1.0-4.0.

[0088] In this plan, a control group, a D group, and an E group were designed, and their tensile strength MD, tensile strength TD, elongation at break retention rate, and friction coefficient with metal were tested for comparison.

[0089] Among them, the control group: 10kg of polypropylene raw material, 10kg of polyethylene raw material;

[0090] Group D: 10kg polypropylene raw material, 1.5kg graphene, 1.5kg polytetrafluoroethylene; 10kg polyethylene raw material, 0.5kg polyimide, 1.5kg molybdenum disulfide, 1.5kg glass fiber;

[0091] Group E: 10kg polypropylene raw material, 2.4kg graphene, 0.8kg polytetrafluoroethylene; 10kg polyethylene raw material, 0.8kg polyimide, 1.0kg molybdenum disulfide, 4.0kg glass fiber;

[0092] Table 2 is a performance table of the plastic geogrid under each component in Example 2.

[0093] Table 2 Performance of plastic geogrids under various components in Example 2

[0094] sample Longitudinal tensile strength / kN / m Transverse tensile strength / kN / m Retention rate of elongation at break MD% Punching dynamic friction coefficient Control group 30 30 16 0.25 Group D 32 33.5 18.1 0.12 Group E 34 34.5 18.3 0.14

[0095] As can be seen from Table 2, in group D, graphene + glass fiber is smaller than polytetrafluoroethylene + molybdenum disulfide, and compared with group E, the strength is slightly lower and the dynamic friction coefficient is smaller, which shows that the combination of graphene and glass fiber is more helpful to improve the overall strength, while the combination of polytetrafluoroethylene + molybdenum disulfide is more helpful to reduce the dynamic friction coefficient of punching.

[0096] Example 3

[0097] A production device for a composite biaxially stretched plastic geogrid comprises a material hopper and an extruder unit connected in sequence, a plurality of supporting and transmitting structures for receiving and transmitting a plurality of plates respectively, a composite device for compositely extruding a plurality of plates, a punching device for punching holes in the composite plates, and a biaxially stretching device for longitudinally and transversely stretching the punched plates, wherein the plurality of supporting and transmitting structures are arranged in parallel up and down.

[0098] The extruder unit comprises a plurality of extruders, and the extruders comprise a screw structure, a heating zone and a die head for extrusion molding which are connected in sequence.

[0099] The composite device comprises a preheating unit, a pressure applying unit and a pressure maintaining unit which are connected in sequence, and one end of the supporting transmission structure is arranged close to the preheating unit.

[0100] It should be noted that the extruder unit, compounding device, punching equipment and biaxial stretching equipment are all prior art equipment, and their working principles and processes are technologies that can be implemented by technicians in this field and will not be described in detail here.

[0101] More preferably, a transmission component is provided between the composite device and the punching device, and between the punching device and the biaxial stretching device, such as a conveyor belt component or the like. This is a prior art and will not be described in detail here.

[0102] More preferably, the upper and lower supporting transmission structures can be respectively arranged close to the two extruders, and the two extruders can be arranged front and back or up and down.

[0103] See also Figure 1-Figure 5 The supporting transmission structure includes a crossbar 1 and a crossbar 4 arranged in parallel with each other, a rotating rod structure 7 connected to the crossbar 1, the rotating rod structure 7 is in separate contact with the crossbar 2 4, an extruded sheet 2 is arranged between the crossbar 1 and the crossbar 2 4, and the extruded sheet 2 is movably mounted on the rotating rod structure 7;

[0104] The upper end surface of the crossbar 1 is provided with an opening groove 11, and the upper end surface of the crossbar 2 is provided with an opening groove 2 41, wherein the upper rotating rod structure 7 is in separate contact with the opening groove 11 and the opening groove 2 41 on the lower rotating rod structure 7.

[0105] When in use, the lower rotating column 73 can enter the opening groove 11 and the opening groove 2 41, and contact the upper end surface of the extruded plate, and interact with the upper rotating column 76 below it to achieve the effect of transmitting the extruded plate.

[0106] The rotating rod structure 7 includes a rotating block 6 and a positioning block 74 respectively arranged near the crossbar 1 and the crossbar 2 4, an upper rotating column 76 and a lower rotating column 73 respectively connected to the rotating block 6 and the positioning block 74 at both ends, a gear 1 71 coaxially connected to one end of the upper rotating column 76, a gear 2 72 coaxially connected to one end of the lower rotating column 73, and a driving motor 75 drivingly connected to the other end of the lower rotating column 73. The upper rotating column 76 and the lower rotating column 73 are arranged parallel to each other, the gear 1 71 and the gear 2 72 are meshed and connected with each other, and a baffle 8 is arranged at the bottom end of the rotating block 6, and the baffle 8 is used to limit the extruded plate falling onto the support platform;

[0107] Under the action of the driving motor 75, the lower rotating column 73 is driven to rotate, and at the same time, under the action of gear 1 71 and gear 2 72, the upper rotating column 76 is driven to rotate. The upper rotating column 76 is on the bottom surface of the extruded plate and drives the extruded plate to move; the lower rotating column 73 enters the open groove 1 11 and the open groove 2 41 below it, contacts the upper end surface of the extruded plate below, and drives the extruded plate below.

[0108] The rotating block 6 is fixedly connected to the vertically arranged power shaft, the power shaft is rotatably connected to the fixed seat 51, the fixed seat 51 is fixed to the outer side of the cross bar 1, and the power shaft is connected to the micro motor 5;

[0109] The outer sides of the crossbar 1 and the crossbar 2 4 are also fixedly connected with fixed columns 3, and the fixed columns 3 are connected to the lifting mechanism. The lifting mechanism can be any mechanical structure as long as it has the effect of lifting, and will not be described in detail here.

[0110] The lifting mechanism is connected to the moving mechanism, and the moving mechanism drives the lifting mechanism and the rotating rod structure to move to the inside of the composite device to achieve the effect of transfer. In this solution, the moving mechanism can be an existing mechanical structure such as a moving vehicle, etc. In order to simplify the design, it is no longer marked in detail in the drawings.

[0111] The preheating unit preheats the different plates delivered, the pressure applying unit applies a certain pressure to the plates after preheating to make them fit together, and the pressure holding unit maintains the pressure for a period of time to ensure that the plates are fully fused.

[0112] The preheating unit, the pressure applying unit and the pressure maintaining unit are all parts of the prior art equipment. To simplify the design, they are not described in detail in the drawings. This is hereby explained.

[0113] The punching equipment includes a special punch, a die arranged under the special punch, and a control system for controlling the punch stroke and the punching force, and is used for punching the composite plate.

[0114] The biaxial stretching equipment includes a longitudinal stretching machine and a transverse stretching machine arranged front and back, which respectively perform longitudinal and transverse stretching on the punched sheet. Both the longitudinal stretching machine and the transverse stretching machine are equipped with a temperature controller, a speed controller and a stretching multiple controller.

[0115] The specific working process of the device of the present invention is as follows:

[0116] First, the sheet is extruded. For example, when producing geogrids for roadbed reinforcement, one extruder adds polypropylene raw materials and additive A, and the other extruder adds polyethylene raw materials and additive B. At the same time, a specific color masterbatch can be added to the hopper of one extruder according to the labeling requirements. The temperature of the polypropylene extruder is set at 200℃, the screw speed is X rpm, and the temperature of the polyethylene extruder is set at 190℃, the screw speed is Y rpm, and sheets of different materials and colors are extruded respectively.

[0117] In the prior art, when the extruded sheet 2 is transferred from the extruder to the composite device, a manipulator is required to arrange and place the multiple extruded sheets 2 up and down, which is inconvenient to operate. In this solution, a supporting transmission structure is designed, which is supported by an upper rotating column 76 below the extruded sheet 2. Under the action of the driving motor 75, it plays a supporting transmission role, which helps to transfer the extruded sheet 2 from the extruder position to the composite device position;

[0118] Specifically, the lifting mechanism is connected to the moving mechanism, and the moving mechanism drives the lifting mechanism and the rotating rod structure to move to the inside of the composite device, thereby achieving a transfer effect.

[0119] Under the action of the micromotor 5, the upper rotating column 76 and the lower rotating column 73 are simultaneously rotated 90° to the bottom of the crossbar 1, so that the upper rotating column 76, the lower rotating column 73 and the crossbar 1 are parallel to each other, so that the extruded sheets 2 arranged up and down fall onto the support platform of the composite device, which is helpful for the subsequent pressurization and pressure holding process;

[0120] Under the action of the baffle 8 below the rotating block 6 and the swing of the positioning block 74, the outer sides of the plurality of extruded plates 2 are made flush, thereby achieving a straightening effect.

[0121] The plates are then composited. After the two extruded plates are conveyed to the composite device, the preheating unit preheats the plates to 160°C, the pressure applying unit applies 8MPa pressure, and the pressure holding unit holds the pressure for 4 minutes to composite the plates into a whole.

[0122] Then the punching operation is carried out, using the punching equipment to punch holes according to the designed hole diameter Z1mm and hole spacing Z2mm. The punch stroke and blanking force are controlled at values ​​A and B respectively to ensure the quality of the holes.

[0123] Finally, in the biaxial stretching operation, the punched plate is first longitudinally stretched on a longitudinal stretching machine at a stretching multiple of 3.5 times, a temperature of 120°C and a stretching speed of speed A, and then transversely stretched on a transverse stretching machine at the same multiple, a temperature of 120°C and a stretching speed of speed B, and at the same time, it is powered on to produce a composite biaxially stretched plastic geogrid that meets the requirements.

[0124] Technical features not described in the present invention can be achieved through or by adopting existing technologies and will not be described in detail here. Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention should also fall within the scope of protection of the present invention.

Claims

1. A method for producing a composite biaxially oriented plastic geogrid, characterized in that it specifically comprises the following steps: Step S1: using two different extruders to perform sheet extrusion operations; Step S2: using a compounding device to perform a compounding operation on a plurality of plates; Step S3: using a punching device to perform a plate punching operation; Step S4: using a longitudinal stretching machine and a transverse stretching machine to perform biaxial stretching operation on the sheet.

2. The method for producing a composite biaxially oriented plastic geogrid according to claim 1, characterized in that, in the step S1, polypropylene raw material, graphene, and polytetrafluoroethylene are added to one of the extruders, and polyethylene raw material, polyimide, molybdenum disulfide, and glass fiber are added to the other extruder; in, By mass, polypropylene raw materials: graphene: polytetrafluoroethylene = (10-15): (1.0-2.4): (0.5-1.5), polyethylene raw materials: polyimide: molybdenum disulfide: glass fiber = (8-12): (0.5-1.0): (1.0-1.5): (1.0-4.0).

3. The method for producing a composite biaxially oriented plastic geogrid according to claim 2, characterized in that, by mass, (graphene + glass fiber) / (polytetrafluoroethylene + molybdenum disulfide) = 1.0-4.

0.

4. The method for producing a composite biaxially oriented plastic geogrid according to claim 1, characterized in that, in the step S2, the extruded different plates are transported to a composite device, the composite device first preheats the plates to make the surface temperature of the plates reach a range suitable for composite, and then the plates are tightly fitted under a certain pressure for a holding time t to make the plates fully fused; in, The compounding temperature can be controlled at 150-180°C, the pressure can be set at 5-10MPa, and the holding time can be 3-5 minutes.

5. The method for producing a composite biaxially oriented plastic geogrid according to claim 1 is characterized in that, in step S3, the composite integral plate enters a punching process, and a punching device is used to perform punching operations according to the hole diameter and hole spacing designed for the geogrid.

6. The method for producing a composite biaxially stretched plastic geogrid according to claim 1, characterized in that, in the step S4, the punched plate is biaxially stretched and powered on at the same time; a longitudinal stretching machine and a transverse stretching machine are used to first stretch the plate in the longitudinal stretching machine along the length direction; then the longitudinally stretched plate enters the transverse stretching machine and is stretched perpendicular to the length direction, and the transverse stretching multiple matches the longitudinal stretching multiple to ensure that the mechanical properties of the grid are uniform in both directions; in, During the stretching process, the stretching temperature is controlled at 110-130℃, and the stretching speed is adjusted according to the thickness and material of the plate.

7. A production device for a composite biaxially stretched plastic geogrid, adopting a production method for a composite biaxially stretched plastic geogrid as described in any one of claims 1 to 6, characterized in that it comprises an extrusion unit connected in sequence, a plurality of supporting and transmitting structures for respectively receiving and transmitting a plurality of plates, a composite device for composite extrusion of a plurality of plates, a punching device for punching the composite plates, and a biaxial stretching device for longitudinally and transversely stretching the punched plates, wherein the plurality of supporting and transmitting structures are arranged in parallel up and down, and a material hopper is provided on the extrusion unit.

8. A production device for a composite biaxially oriented plastic geogrid according to claim 7, characterized in that the composite device comprises a preheating unit, a pressure applying unit and a pressure maintaining unit connected in sequence, and one end of the supporting transmission structure is arranged close to the preheating unit.

9. A production device for a composite biaxially oriented plastic geogrid according to claim 7, characterized in that the supporting transmission structure comprises a crossbar 1 (1) and a crossbar 2 (4) arranged in parallel with each other, and a rotating rod structure (7) connected to the crossbar 1 (1), the rotating rod structure (7) being in separate contact with the crossbar 2 (4), an extruded plate (2) being arranged between the crossbar 1 (1) and the crossbar 2 (4), and the extruded plate (2) being movably mounted on the rotating rod structure (7); The upper end surface of the cross bar 1 (1) is provided with an opening groove 1 (11), and the upper end surface of the cross bar 2 (4) is provided with an opening groove 2 (41), wherein the upper rotating rod structure (7) is in separate contact with the opening groove 1 (11) and the opening groove 2 (41) on the lower rotating rod structure (7).

10. A production device for a composite biaxially stretched plastic geogrid according to claim 7, characterized in that the rotating rod structure (7) comprises a rotating block (6) and a positioning block (74) respectively arranged near the cross bar 1 (1) and the cross bar 2 (4), an upper rotating column (76) and a lower rotating column (73) whose two ends are rotatably connected to the rotating block (6) and the positioning block (74), respectively, a gear 1 (71) coaxially connected to one end of the upper rotating column (76), a gear 2 (72) coaxially connected to one end of the lower rotating column (73), and a driving motor (75) drivingly connected to the other end of the lower rotating column (73), the upper rotating column (76) and the lower rotating column (73) are arranged parallel to each other, the gear 1 (71) and the gear 2 (72) are meshed and connected with each other, and a baffle (8) is arranged at the bottom end of the rotating block (6); The rotating block (6) is fixedly connected to a vertically arranged power shaft, the power shaft is rotatably connected to a fixed seat (51), the fixed seat (51) is fixed on the outer side of the cross bar (1), and the power shaft is connected to the micro motor (5); The outer sides of the crossbar 1 (1) and the crossbar 2 (4) are respectively fixedly connected with fixing columns (3), and the fixing columns (3) are connected to the lifting mechanism.

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