Manufacturing process of polyester filament spun-bonded needle-punched geotextile

Abstract

The invention relates to the technical field of geotechnical cloth manufacturing, in particular to a manufacturing process of polyester filament spun-bonded needle-punched geotechnical cloth. According to the invention, the crystallization fan and the pulsation valve are combined in the storage tank to perform pre-crystallization treatment on the chips, so that moisture and impurities of the polyester chips can be effectively removed, then the flow of compressed air is utilized to drive the chip particles to form a granular fluid, and no mechanical contact exists in the conveying process, so that the risk that raw materials are polluted can be reduced; and then a fiber web is formed by using a roller drafting device and a yarn swaying machine, so that the size of the raw materials is more uniform and consistent, and the mechanical property of the manufactured polyester filament spun-bonded needle-punched geotextile is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of geotextile production, and more specifically, to a production process for polyester filament spunbonded needle-punched geotextiles. Background Art

[0002] Geotextiles, also known as geotextiles, are water-permeable geosynthetic materials made of synthetic fibers by needle punching or weaving, and generally have good tensile strength, corrosion resistance, and anti-aging properties. They are widely used in fields such as construction, transportation, and water conservancy projects.

[0003] The existing production process of geotextiles is to form continuous filaments by crystallizing and drying polyester chips, melting and extruding, and cooling and stretching, and then to obtain polyester filament spunbonded needle-punched geotextiles through filament splitting and web laying. In the above production process, in the prior art, hot plate heating or infrared radiation is generally used to clean and dry polyester chips. Among them, hot plate heating relies on heat conduction. When the chips are uneven in thickness, the hot plate heating method will cause uneven heating of the chips and easily lead to caking of the chips; when using infrared radiation, although it can penetrate the material for internal heating, precise temperature control is required to prevent local overheating from causing degradation of the chips, and infrared radiation is sensitive to material properties (such as dielectric constant), and the process adjustment is difficult. In addition, in the prior art, after melting and extrusion, the raw materials are generally transported to the next process by mechanical conveying. During this process, due to mechanical contact with the raw materials, there is a risk of raw material contamination, which is not conducive to maintaining the cleanliness of the raw materials. The above factors will affect the mechanical properties of the produced polyester filament spunbonded needle-punched geotextiles. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to ensure the mechanical properties of the produced polyester filament spunbonded needle-punched geotextiles.

[0005] The purpose of the present invention is to provide a production process for polyester filament spunbonded needle-punched geotextiles, which realizes temperature control of polyester chips by selecting a new heating method, and avoids mechanical contact during the raw material transfer process, thereby ensuring the mechanical properties of the produced polyester filament spunbonded needle-punched geotextiles.

[0006] To achieve the above object, the present invention provides a production process for polyester filament spunbonded needle-punched geotextiles, including the following steps:

[0007] S1. Polyester chips are sent to a wet chip storage tank for storage by a conveying device, and in the storage tank, a crystallization fan and a pulsating valve are used in combination to perform pre-crystallization treatment on the chips;

[0008] Then the chips are sent to a drying tower for preliminary drying, and then the chips are crystallized and dried to remove moisture to obtain chip particles, and the chip particles are sent to a dry chip storage tank by a secondary conveying device;

[0009] S2. Feed the sliced particles into the feeding pipeline, use the compressed air generated by an air compressor to drive the sliced particles to form a fluid, and transport the fluid to a screw extruder. After melting and plasticizing into a melt, use a melt filter to remove impurities from the melt. After treatment, transport the melt to a spinning box.

[0010] The spinning box evenly distributes the melt and transports it to a spinning component. Then, a melt streamlet is ejected from the spinneret holes of the spinning component. After the melt streamlet is cooled by side blowing, it is driven by a high-pressure air flow to pass through a drafting device. Then, the drafting device drafts the melt streamlet to form filaments. Each bundle of filaments is laid on the mesh belt of a cross-lapper by a filament laying machine to form a fiber web.

[0011] S3. The mesh belt of the cross-lapper transports the fiber web to a needling machine, and the needling machine performs a fixing and shaping treatment on the fiber web to form a fabric surface by combining the fiber webs.

[0012] After two needling treatments on the fabric surface, transport the fabric surface to an ironing machine. The fabric surface is synchronously clamped and ironed by the upper and lower opposed hot ironing rollers of the hot ironing machine to complete the shaping treatment.

[0013] S4. First, transport the fabric surface that has completed the shaping treatment to a tension frame for uniform stress treatment, and then, after passing through a fabric storage tension adjustment treatment, transport it to a winding machine. Finally, the winding machine trims the edges and winds it into a roll to produce a polyester spunbonded needle-punched geotextile.

[0014] As a further improvement of this technical solution, in step S1, the operating temperature range of the crystallization fan is 170 - 210 °C, and the pulsating valve is adjusted to the fully open mode.

[0015] As a further improvement of this technical solution, in step S1, when initially drying in the drying tower, use a heating fan and a dehumidifier to dry the sliced particles and remove moisture.

[0016] As a further improvement of this technical solution, in step S2, after filtering out impurities through the melt filter, transport it to the spinning box through a melting pipeline, and the filtration accuracy range of the melt filter is 10 - 20 microns.

[0017] As a further improvement of this technical solution, in step S2, the melt is first evenly distributed to each metering pump by the spinning box, and then quantitatively transported to each spinning component by the metering pump. The aperture size of the spinneret holes is 0.1 mm, and the hole pitch between the spinneret holes is 1 mm.

[0018] As a further improvement of this technical solution, in step S2, the formed melt streamlet is droplet-shaped, the drafting device is a roller drafting system, and the roller drafting system is composed of multiple rollers, and each roller has specific speed and temperature control.

[0019] As a further improvement of this technical solution, in step S3, the fixing and shaping method is to penetrate the fibers by the up-and-down movement of the needles of the needle punching machine, so that the fibers form through holes.

[0020] As a further improvement of this technical solution, in step S3, the heating temperature of the upper roller body is 210 °C, and the heating temperature of the lower roller body is 180 °C.

[0021] As a further improvement of this technical solution, in step S4, the uniform force treatment is that the tensioning frame applies tension to the fabric surface by clamping the fabric surface, and then makes the tension uniform and maintains the tension, so that the fabric surface is uniformly stressed in the entire width and length.

[0022] In the present invention, a crystallization fan and a pulsating valve are used to pre-crystallize the chips, and then compressed air is used to drive the chip particles into a fluid, and then a roller stretching device + a fiber laying machine are used to form a fiber web, so as to achieve the consistency of the raw material size.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] In the production process of this polyester filament spunbonded needle-punched geotextile, a crystallization fan and a pulsating valve are used in combination in the storage tank to pre-crystallize the chips, which can effectively remove the moisture and impurities of the polyester chips. Then, the flow of compressed air is used to drive the chip particles to form a particulate fluid. There is no mechanical contact during the transportation process, which can reduce the risk of raw material contamination and maintain the cleanliness of the raw materials. Subsequently, a roller stretching device + a fiber laying machine are used to form a fiber web, so as to achieve a more uniform consistency of the raw material size and ensure the mechanical properties of the produced polyester filament spunbonded needle-punched geotextile. Description of the Drawings

[0025] Figure 1 It is the overall flow chart of the present invention. Detailed Embodiments

[0026] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0027] The purpose of the present invention is to provide a production process for polyester filament spunbonded needle-punched geotextile, and the specific steps are as follows:

[0028] S1. The polyester chips (fiber grade) are sent to the wet chip storage tank by a conveying device and stored therein. In the storage tank, a crystallization fan and a pulsating valve are combined to perform pre-crystallization treatment on the chips. The purpose of the pre-crystallization treatment is to remove the moisture and impurities in the raw material of the filament needle-punched geotextile - polyethylene polyester chips, and ensure the purity of the melt after the chips are melted;

[0029] Among them, the working temperature range of the crystallization fan is 170 - 210 °C, and the pulsating valve is adjusted to the fully open mode. When the crystallization fan and the pulsating valve are adjusted to these state parameters, the moisture and impurities in the polyester chips can be effectively removed, and the drying and dust removal effects on the chips are the best;

[0030] The pre-crystallization treatment in the production of geotextiles is mainly to prevent the chips from caking during drying. The chips are prone to softening and sticking at high temperatures, so pre-crystallization is to increase the crystallinity of the chips and make them harder and less likely to adhere.

[0031] Compared with methods such as hot plate conduction, microwave heating, and vacuum drying, the crystallization fan + pulsating valve has the following unique advantages:

[0032] 1. Dynamic heat transfer and high efficiency and uniformity;

[0033] 2. The pulsed air flow (controlled by the pulsating valve) periodically impacts the chips, forcing the chips to turn over and avoiding accumulation; the crystallization fan provides stability; 3. Hot air circulation to ensure uniform temperature;

[0034] 4. More efficient than other static or local heating methods, significantly reducing the risk of caking;

[0035] 5. Accelerate molecular chain rearrangement;

[0036] 6. The pulsed air flow induces mechanical vibration, promotes the rapid and orderly arrangement of the internal molecular chains of the polyester chips, shortens the pre-crystallization time and improves the crystallinity at the same time;

[0037] 7. Real-time removal of moisture;

[0038] 8. The high-speed air flow synchronously takes away the moisture, avoiding the interference of water molecules on the crystallization process and ensuring the quality of subsequent spinning (traditional methods require separate drying and crystallization processes);

[0039] 9. Process controllability and scalability;

[0040] 10. By adjusting the pulsation frequency, air temperature and air speed, it can be flexibly adapted to different chip specifications (such as viscosity, moisture content); suitable for large-scale continuous production.

[0041] The crystallization fan and the pulsating valve are used together, and the resulting effects have core effects that cannot be replaced by other heating methods: The dynamic thermodynamic environment jointly constructed by the crystallization fan and the pulsating valve is the core to achieve efficient and uniform pre-crystallization. It is difficult for other single means to synchronously achieve the synergistic effects of temperature control, mechanical disturbance, and humidity management; compared with high-end processes (such as microwave), this combined equipment has low cost, simple maintenance, and energy consumption and production efficiency are more suitable for industrial needs.

[0042] Then, when the slices are sent to the drying tower for preliminary drying, in the drying tower, a heating fan and a dehumidifier are used to dry the slices and remove moisture. After the slices are crystallized and dried to remove moisture, slice particles are obtained. The slice particles are sent to the dry slice storage tank by a secondary conveying device for spinning.

[0043] S2. Feed the slice particles that have undergone drying and crystallization treatment into the feeding pipeline. Utilize the flow of compressed air generated by an air compressor to drive the slice particles to form a fluid with particle properties. The compressed air generated by the air compressor undergoes oil-free and moisture-free treatment. The compressed air then transports the fluid to a screw extruder, where it is melted and plasticized into a flowing melt. Then, a melt filter is used to filter out impurities from the melt. After treatment, the melt is transported to the spinning box.

[0044] Principle of compressed air drive: The air compressor compresses air to a certain pressure and stores it in an air tank or pipeline network. Then, the compressed air is transported to the raw material conveying system through a dedicated conveying pipeline. When the compressed air passes through the pipeline, a high-speed air flow is generated. This air flow can drive the raw materials (such as polyester slices) to move and transport them to the designated location.

[0045] Compared with the traditional mechanical conveying method, the compressed air conveying method can significantly reduce energy consumption because it does not require a large number of mechanical devices to drive the conveying system. Compressed air can generate a high-speed air flow, which can quickly and effectively transport raw materials to the designated location, improving the overall efficiency of the production line. Importantly, since there is no mechanical contact during the compressed air conveying process, the risk of raw material contamination can be reduced, and the cleanliness of the raw materials can be maintained.

[0046] Specifically, after filtering out impurities through the melt filter, it is transported to the spinning box through a melting pipeline. The filtration accuracy range of the melt filter is 10 - 20 microns, aiming to remove impurities and impure substances in the melt to ensure that the produced geotextile filaments have good quality and uniformity.

[0047] The spinning box evenly distributes the melt and then transports it to the spinning pack. Then, the melt stream is ejected from the spinneret holes of the spinning pack to form a melt filament. Specifically, the melt is first evenly distributed by the spinning box to each metering pump, and then quantitatively transported by the metering pump to each spinning pack. Among them, the aperture size of the spinneret hole is 0.1 mm. The fineness and uniformity of the filaments ejected from this aperture are the best. The pitch between the spinneret holes is 1 mm to ensure the uniform distribution of the filaments and avoid entanglement. The material of the spinneret hole is 45# steel, which has high-temperature resistance, corrosion resistance, and wear resistance. The spinneret hole is a very important component in the filament production line, which directly affects the quality and production efficiency of the filaments;

[0048] The melt filament formed by the filament geotextile production line flows in a droplet shape (also known as fibrous flow). After the melt filament is cooled by side blowing in sequence, it is then driven by high-pressure air through a stretching device. Then, after the stretching device performs stretching treatment on the melt filament to form filaments, the filament laying machine lays each bundle of filaments onto the mesh belt of the cross-laying machine to form a fiber web;

[0049] Droplet-shaped flow means that after the melt passes through the spinneret hole, a series of droplets are formed, and these droplets will be stretched and deformed into fibers.

[0050] This type of flow is very important for the subsequent heat treatment process added in the present invention because it can improve the fineness of the fibers, increase the uniformity of the fibers, improve the mechanical properties of the filaments, and moreover, droplet-shaped flow can increase the production speed and efficiency of the filaments.

[0051] In addition, droplet-shaped flow can ensure the quality and uniformity of the filaments, improve the mechanical properties and production efficiency of the filaments. These requirements can ensure that the production line of filament geotextiles has the characteristics of high efficiency, stability, and reliable quality.

[0052] In addition, the stretching device is a roller stretching system. The roller stretching system consists of multiple rollers, and each roller has specific speed and temperature control. The roller stretching system stretches and heat-sets the filaments through the rollers. The spun filaments formed after the melt filament is cooled form a fiber web with a certain thickness on the conveyor belt of the cross-laying machine. By controlling the extrusion amount of the metering pump and adjusting the linear speed of the mesh belt, the gram weight of the fiber web can be adjusted.

[0053] The present invention uses a roller stretching device + a filament laying machine. Roller stretching can evenly stretch the raw material, thereby achieving more uniform consistency in the size of the raw material. And by stretching the melt filament through the roller to form filaments, the raw material can exhibit better stability and consistency in the subsequent processing. Roller stretching can align the fibers in a specific direction, which is very important for the subsequent weaving or braiding process. Since the raw material is evenly stretched and directionally aligned, the finally produced geotextile can have better mechanical properties, such as tensile strength and elastic modulus.

[0054] In summary, the cylinder draft and the fiber laying machine play different roles in the production line of polyester filament spunbonded needle-punched geotextiles. The cylinder draft can achieve effects such as uniform stretching, improving the stability of raw materials, improving fiber orientation, and enhancing the mechanical properties of materials, which cannot be achieved by the fiber laying machine.

[0055] S3. The mesh belt of the cross-lapper sends a fiber web with a certain thickness to the needle-punching machine, and the needle-punching machine performs fixation and shaping treatment on the fiber web, so that the fiber web is combined to form a cloth surface;

[0056] After two needle-punching treatments on the cloth surface, the cloth surface is conveyed to a calender. The cloth surface is synchronously clamped and ironed by the upper and lower opposed hot calender rolls of the hot calender to complete the shaping treatment. The purpose is to improve the pores between the filament bundles' entanglement, make the pores smaller, and improve the dry sieve pore size performance. The heating temperature of the upper roll body is 210°C, and the heating temperature of the lower roll body is 180°C;

[0057] It should be noted that the fixation and shaping method is that the needles of the needle-punching machine move up and down at a certain frequency and speed to perform through-punching on the fibers, so that the fibers form through holes.

[0058] Among them, through-punching refers to that the needles of the needle-punching machine pass through from one side of the geotextile to the other side, forming through holes. These holes can cross-link the fibers of the geotextile to achieve the strengthening and stabilization of the geotextile.

[0059] The principle of through-punching is as follows: Needle movement: The needles of the needle-punching machine move at a certain frequency and speed to form up and down movement.

[0060] Geotextile penetration: The needles pass through from one side of the geotextile to the other side, forming through holes. Through-punching can quickly and efficiently achieve the strengthening and stabilization of the geotextile. Through-punching can produce good mechanical bonding to ensure that the geotextile has good strength and stability. The purpose is to enhance the mutual entanglement between the filament bundles, and then further perform fixation and shaping by the main needle-punching machine, that is, further enhance the mutual entanglement between the filament bundles;

[0061] S4. The cloth surface after the shaping treatment is first conveyed to a tension frame for uniform stress treatment, and then after the storage cloth tension adjustment treatment, it is conveyed to a winding machine. Finally, the polyester filament spunbonded needle-punched geotextile is formed into a roll by trimming the edges of the winding machine. The uniform stress treatment is that the tension frame applies tension to the cloth surface by clamping the cloth surface, and then makes the tension uniform and maintains the tension, so that the cloth surface is uniformly stressed in the whole width and length, maintains the consistency of shape and size, improves the strength and stability, and improves the appearance.

[0062] According to the differences in process parameters during the preparation process, the following specific embodiments are used to further illustrate a production process of polyester filament spunbonded needle-punched geotextiles provided by the present invention.

[0063] Example 1

[0064] S1. The polyester chips are sent to the wet chip storage tank by the conveying equipment and stored therein. In the storage tank, a crystallization fan and a pulsating valve are used in combination to perform pre-crystallization treatment on the chips. The operating temperature range of the crystallization fan is 170°C, and the pulsating valve is adjusted to the fully open mode;

[0065] Then, when the chips are sent to the drying tower for preliminary drying, in the drying tower, a heating fan and a dehumidifier are used to dry the chips and remove moisture. After the chips are subjected to crystallization and drying treatment to remove moisture, chip particles are obtained. The chip particles are sent to the dry chip storage tank by the secondary conveying equipment;

[0066] S2. The chip particles are fed into the feeding pipeline, and the flow of compressed air generated by the air compressor is used to drive the chip particles to form a fluid with particle properties. The compressed air then transports the fluid to the screw extruder, where it is melted and plasticized into a flowing melt. After that, a melt filter is used to filter out impurities from the melt. After treatment, the melt is transported to the spinning box. Specifically, after filtering out impurities through the melt filter, it is transported to the spinning box through the melting pipeline, and the filtration accuracy range of the melt filter is 20 microns;

[0067] The spinning box evenly distributes the melt and transports it to the spinning assembly. Then, a melt stream is ejected from the spinneret holes of the spinning assembly. Specifically, the melt is first evenly distributed to each metering pump by the spinning box, and then quantitatively transported to each spinning assembly by the metering pump. Among them, the aperture size of the spinneret holes is 0.1 mm, the hole pitch between the spinneret holes is 1 mm. After the melt stream is cooled by the side blowing air, it is then driven by a high-pressure air flow to pass through the stretching device. Then, the stretching device performs stretching treatment on the melt stream to form filaments, and each bundle of filaments is laid on the mesh belt of the cross-lapper by the filament laying machine to form a fiber web;

[0068] In addition, the stretching device is a roller stretching system, which consists of multiple rollers, and each roller has specific speed and temperature control for stretching and heat setting the filaments;

[0069] S3. The mesh belt of the cross-lapper sends a fiber web with a certain thickness to the needling machine, and the needling machine performs fixing and shaping treatment on the fiber web to make the fiber web combine to form a fabric surface;

[0070] After two needling treatments on the fabric surface, the fabric surface is transported to the ironing machine. The fabric surface is synchronously clamped and ironed by the upper and lower opposed hot ironing rollers of the hot ironing machine to complete the shaping treatment. The heating temperature of the upper roller body is 210°C, and the heating temperature of the lower roller body is 180°C;

[0071] It should be noted that the fixing and shaping method is to perform through-needling on the fibers by the up-and-down movement of the needles of the needling machine, so that the fibers form through needle holes;

[0072] S4. First, the cloth surface that has completed the shaping process is transported to a tension rack for uniform stress treatment, and then after passing through the storage cloth tension adjustment treatment, it is transported to a winding machine. Finally, it is cut and wound by the winding machine to form polyester filament spunbonded needle-punched geotextile. The uniform stress treatment is that the tension rack applies tension to the cloth surface by clamping the cloth surface, and then equalizes and maintains the tension, so that the cloth surface is uniformly stressed across the entire width and length, maintaining the consistency of shape and size.

[0073] Example 2

[0074] S1. Polyester chips are sent to a wet chip storage tank by a conveying device and stored. In the storage tank, a crystallization fan and a pulsating valve are used in combination to perform pre-crystallization treatment on the chips. The operating temperature range of the crystallization fan is 190 °C, and the pulsating valve is adjusted to the fully open mode.

[0075] Then, when the chips are sent to the drying tower for preliminary drying, in the drying tower, a heating fan and a dehumidifier are used to dry the chips and remove moisture. After the chips are crystallized and dried to remove moisture, chip particles are obtained. The chip particles are sent to a dry chip storage tank by a secondary conveying device.

[0076] S2. The chip particles are fed into a feeding pipeline. The flow of compressed air generated by an air compressor is used to drive the chip particles to form a granular fluid. The compressed air then transports the fluid to a screw extruder, where it is melted and plasticized into a flowing melt. Then, a melt filter is used to filter out impurities from the melt. After processing, the melt is transported to a spinning box. Specifically, after filtering out impurities through the melt filter, it is transported to the spinning box through a melting pipeline, and the filtration accuracy range of the melt filter is 15 microns.

[0077] The spinning box evenly distributes the melt and transports it to the spinning components. Then, a melt stream is ejected from the spinneret holes of the spinning components. Specifically, the melt is first evenly distributed to each metering pump by the spinning box, and then quantitatively transported to each spinning component by the metering pump. Among them, the aperture size of the spinneret holes is 0.1 mm, and the hole pitch between the spinneret holes is 1 mm. After the melt stream is cooled by side blowing, it is then driven by a high-pressure air flow through a stretching device. Then, the stretching device performs stretching treatment on the melt stream to form filaments, and each bundle of filaments is laid on the mesh belt of a cross-laying machine by a filament laying machine to form a web.

[0078] In addition, the stretching device is a roller stretching system, which consists of multiple rollers, and each roller has specific speed and temperature control for stretching and heat setting the filaments.

[0079] S3. The mesh belt of the cross-laying machine sends a web of a certain thickness to a needling machine, and the needling machine performs fixation and shaping treatment on the web to form a cloth surface by combining the webs.

[0080] After the fabric surface is subjected to two needle punching treatments, the fabric surface is conveyed to an ironing machine, and the fabric surface is clamped and ironed synchronously by the upper and lower opposed hot ironing rollers of the hot ironing machine to complete the shaping treatment. The heating temperature of the upper roller body is 210 °C, and the heating temperature of the lower roller body is 180 °C;

[0081] It should be noted that the fixing and shaping method is to penetrate the fibers through needle punching by the up and down movement of the needles of the needle punching machine, so that the fibers form through needle holes;

[0082] S4. The fabric surface after the shaping treatment is first conveyed to a tension frame for uniform stress treatment, and then after passing through the fabric storage tension adjustment treatment, it is conveyed to a winding machine. Finally, it is cut and wound by the winding machine to form a polyester filament spunbond needle-punched geotextile. The uniform stress treatment is that the tension frame applies tension to the fabric surface by clamping the fabric surface, and then evenly distributes and maintains the tension, so that the fabric surface is uniformly stressed in the entire width and length, and the shape and size are kept consistent.

[0083] Example 3

[0084] S1. The polyester chips are sent to a wet chip storage tank for storage by a conveying device. In the storage tank, a crystallization fan and a pulsating valve are used in combination to perform pre-crystallization treatment on the chips. The working temperature range of the crystallization fan is 210 °C, and the pulsating valve is adjusted to the fully open mode;

[0085] Then, when the chips are sent to the drying tower for preliminary drying, in the drying tower, a heating fan and a dehumidifier are used to dry the chips and remove moisture. After the chips are crystallized and dried to remove moisture, chip particles are obtained. The chip particles are sent to a dry chip storage tank by a secondary conveying device;

[0086] S2. The chip particles are fed into a feeding pipeline, and the flow of compressed air generated by an air compressor is used to drive the chip particles to form a fluid with particle properties. The compressed air then conveys the fluid to a screw extruder and melts and plasticizes it into a flowing melt. Then, a melt filter is used to filter out impurities from the melt. After the treatment, the melt is conveyed to a spinning box. Specifically, after filtering out impurities through the melt filter, it is conveyed to the spinning box through a melting pipeline, and the filtration accuracy range of the melt filter is 10 microns;

[0087] The spinning box evenly distributes the melt and conveys it to a spinning component. Then, a melt thin stream is ejected from the spinneret holes of the spinning component. Specifically, the melt is first evenly distributed to each metering pump by the spinning box, and then quantitatively conveyed to each spinning component by the metering pump. Among them, the aperture size of the spinneret hole is 0.1 mm, and the hole pitch between the spinneret holes is 1 mm. After the melt thin stream is cooled by side blowing, it is then driven by a high-pressure air flow to pass through a stretching device. Then, the stretching device performs stretching treatment on the melt thin stream to form filaments, and each bundle of filaments is laid on the mesh belt of a cross-laying machine by a filament laying machine to form a fiber web;

[0088] In addition, the drafting device is a roller drafting system, which consists of multiple rollers, and each roller has specific speed and temperature control for stretching and heat setting filaments.

[0089] S3. The mesh belt of the cross-lapper feeds a fibrous web of a certain thickness to the needling machine, and the needling machine fixes and shapes the fibrous web, so that the fibrous web is combined to form a fabric surface.

[0090] After two needling treatments on the fabric surface, the fabric surface is conveyed to the calender. The fabric surface is synchronously clamped and ironed by the upper and lower opposed calender rolls of the heat calender to complete the setting treatment. The heating temperature of the upper roll body is 210°C, and the heating temperature of the lower roll body is 180°C.

[0091] It should be noted that the fixing and shaping method is to penetrate the fibers by the up and down movement of the needles of the needling machine, so that the fibers form through needle holes.

[0092] S4. The fabric surface after the setting treatment is first conveyed to the tension frame for uniform stress treatment, then conveyed to the winding machine after the storage fabric tension adjustment treatment, and finally cut and wound by the winding machine to form a polyester spunbonded needle-punched geotextile. The uniform stress treatment is that the tension frame applies tension to the fabric surface by clamping the fabric surface, then equalizes the tension and maintains the tension, so that the fabric surface is uniformly stressed in the whole width and length, and the shape and size are kept consistent.

[0093] Table 1 Comparison of process parameters in Examples 1-3

[0094] Crystallization fan operating temperature / °C Filtration accuracy / µm Example 1 170 20 Example 2 190 15 Example 3 210 10

[0095] Comparative Example 1

[0096] This comparative example adopts the manufacturing process of Example 1, sets the working temperature of the crystallization fan to 150 degrees Celsius, and the rest remains unchanged. The specific steps are similar to those of Example 1, and will not be elaborated in this comparative example.

[0097] Comparative Example 2

[0098] This comparative example adopts the manufacturing process of Example 1, sets the working temperature of the crystallization fan to 220 degrees Celsius, and the rest remains unchanged. The specific steps are similar to those of Example 1, and will not be elaborated in this comparative example.

[0099] Comparative Example 3

[0100] This comparative example adopts the manufacturing process of Example 1, sets the filtration accuracy of the melt filter to 5 microns, and the rest remains unchanged. The specific steps are similar to those of Example 1, and will not be elaborated in this comparative example.

[0101] Comparative Example 4

[0102] This comparative example uses the manufacturing process of Example 1, sets the filtration accuracy of the melt filter to 15 microns, and keeps the rest unchanged. The specific steps are similar to those of Example 1 and will not be elaborated here.

[0103] Table 2 Comparison of process parameters in Example 1 and Comparative Examples 1-4

[0104]

[0105]

[0106] Comparative Example 5

[0107] This comparative example uses the preparation method of Example 1, changes the step of pre-crystallizing the chips by combining a crystallization fan and a pulsating valve to pre-crystallizing the chips by using hot plate conduction heating, and keeps the rest unchanged. The specific steps are similar to those of Example 1 and will not be elaborated here.

[0108] Comparative Example 6

[0109] This comparative example uses the preparation method of Example 1, changes the step of pre-crystallizing the chips by combining a crystallization fan and a pulsating valve to pre-crystallizing the chips by using microwave heating, and keeps the rest unchanged. The specific steps are similar to those of Example 1 and will not be elaborated here.

[0110] Comparative Example 7

[0111] This comparative example uses the preparation method of Example 1, changes the step of pre-crystallizing the chips by combining a crystallization fan and a pulsating valve to pre-crystallizing the chips by using vacuum drying, and keeps the rest unchanged. The specific steps are similar to those of Example 1 and will not be elaborated here.

[0112] Test Example

[0113] Geotextiles were prepared respectively according to the manufacturing processes provided in Examples 1-3 and Comparative Examples 1-5, and the properties of the geotextiles were tested. According to "GB / T 15788 Geosynthetics - Wide-width tensile test", specimens of 200 mm × 100 mm were cut from the geotextiles, and then a tensile testing machine was used to stretch them at a constant rate until they broke, recording the maximum elongation before fracture under the maximum load (elongation rate = (length of the stretched geotextile - original length of the geotextile) / original length of the geotextile × 100%), and the results were recorded in Table 3.

[0114] Table 3 Comparison of the properties of geotextiles in Examples and Comparative Examples

[0115]

[0116]

[0117] As can be seen from Table 3, the maximum elongation rates of the geotextiles prepared in Examples 1-3 are not less than 25%. When comparing Examples 1-3 with Comparative Examples 1-7, the maximum elongation rates of the geotextiles made in Comparative Examples 1-7 are significantly lower than those of the geotextiles made in Examples 1-3.

[0118] Under the working conditions of this embodiment, the geotextiles prepared in Examples 1-3 have good elongation rates, indicating that the polyester filament spunbonded needle-punched geotextiles made by the manufacturing process provided by the present invention have good mechanical properties.

[0119] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions in the specification are only preferred examples of the present invention and are not used to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A manufacturing process for polyester filament spunbonded needle-punched geotextile, characterized in that, It includes the following steps: S1. The polyester chips are sent to the wet chip storage tank by the conveying equipment and stored. In the storage tank, a crystallization fan and a pulsating valve are combined to perform pre-crystallization treatment on the chips; Then the chips are sent to the drying tower for preliminary drying, and then the chips are crystallized and dried to remove moisture to obtain chip particles. The chip particles are sent to the dry chip storage tank by the secondary conveying equipment; S2. The chip particles are fed into the feeding pipeline, and the compressed air generated by the air compressor is used to drive the chip particles to form a fluid. The fluid is transported to the screw extruder and melted and plasticized into a melt. Then, the melt filter is used to filter out impurities from the melt. After treatment, the melt is transported to the spinning box; The spinning box evenly distributes the melt and transports it to the spinning component. Then, a melt fine stream is ejected from the spinneret holes of the spinning component. After the melt fine stream is cooled by the side air blow, it is driven by the high-pressure air flow to pass through the stretching device. Then, the stretching device performs stretching treatment on the melt fine stream to form filaments. Each bundle of filaments is laid on the mesh belt of the cross-lapper by the filament laying machine to form a fiber web; S3. The mesh belt of the cross-lapper transports the fiber web to the needling machine, and the needling machine performs fixation and shaping treatment on the fiber web to form a fabric surface by combining the fiber webs; After two needling treatments on the fabric surface, the fabric surface is transported to the calender. The fabric surface is clamped and ironed synchronously by the upper and lower opposed hot calender rollers of the hot calender to complete the shaping treatment; S4. The fabric surface that has completed the shaping treatment is first transported to the tension frame for uniform stress treatment, and then after passing through the storage fabric tension adjustment treatment, it is transported to the winding machine. Finally, it is trimmed and wound into a roll by the winding machine to produce a polyester spunbond needle-punched geotextile.

2. The manufacturing process of the polyester filament spunbonded needle-punched geotextile according to claim 1, characterized in that: In S1, the operating temperature range of the crystallization fan is 170 - 210 °C, and the pulsating valve is adjusted to the fully open mode.

3. The manufacturing process of the polyester filament spunbonded needle-punched geotextile according to claim 1, characterized in that: In S1, when performing preliminary drying in the drying tower, a heating fan and a dehumidifier are used to dry the chips and remove moisture.

4. The manufacturing process of the polyester filament spunbonded needled geotextile according to claim 1, characterized in that: In S2, after filtering out impurities through the melt filter, it is transported to the spinning box through the melting pipeline, and the filtration accuracy range of the melt filter is 10 - 20 microns.

5. The manufacturing process of the polyester filament spunbonded needle-punched geotextile according to claim 1, characterized in that: In S2, the melt is first evenly distributed to each metering pump by the spinning box, and then quantitatively transported to each spinning component by the metering pump. The aperture size of the spinneret holes is 0.1 mm, and the hole pitch between the spinneret holes is 1 mm.

6. The manufacturing process of the polyester filament spunbonded needled geotextile according to claim 1, characterized in that: In S2, the formed melt fine stream is in the shape of a droplet, and the stretching device is a roller stretching system. The roller stretching system consists of multiple rollers, and each roller has specific speed and temperature control.

7. The manufacturing process of the polyester filament spunbonded needle-punched geotextile according to claim 1, characterized in that: In S3, the fixation and shaping method is to perform through-needling on the fibers by the up-and-down movement of the needles of the needling machine, so that the fibers form through needle holes.

8. The production process of the polyester filament spunbonded needle-punched geotextile according to claim 1, characterized in that: In S3, the heating temperature of the upper roller body is 210 °C, and the heating temperature of the lower roller body is 180 °C.

9. The manufacturing process of the polyester filament spunbonded needle-punched geotextile according to claim 1, characterized in that: In S4, the uniform stress treatment is that the tension frame applies tension to the fabric surface by clamping the fabric surface, then evenly distributes the tension and maintains the tension, so that the fabric surface is uniformly stressed in the entire width and length.

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