Spunbond non-woven fabric production process

Definition of spunbond non-woven fabric:

The spunbond method is a non-woven fabric production method of spinning directly into a net. During spinning and melting, the process method of non-woven products formed by spinning, laying net and then strengthening.

Spunbond process flow:

Feeding-melt spinning-filtration-cooling-air drafting-spreading-hot rolling-winding-packaging

1 Feeding

1 In the feed, there should be no hard objects such as metal, and no water. Ensure cleanliness.

2 Lack of material: fan failure, filter blockage, pipeline leakage, injection machine failure alarm

3 Injection machine: using weighing type, directly input the required percentage. Two melt spinning

2 screw extruder

2.1 Function: Melt solid slices into melt

Under a certain head pressure, the melt is quantitatively output to compress, exhaust, mix and materialize the material
2.2 Screw segmentation: feeding section, compression section, metering section
Feed section: complete the supply of slices, and the feed section is solid. Compression section: complete melting, solid and liquid coexisting section
Metering section: complete quantitative and extrusion, single-phase melt

2.3 Temperature setting
Judge and set according to the height of the slice melt index. Usually the melt index range of non-woven fabric spinning needs: 15-45g/10min. Generally, if the melt index is high, the molecular weight distribution is large, the molecular weight is small, and the screw temperature is relatively low. If the melt index is small, the molecular weight distribution is small, the molecular weight is large, and the screw temperature is relatively high. If the melt index is between 15-25g/10min, a molecular weight regulator (modified masterbatch) needs to be added.

3 filter

To complete the filtration of the melt, the E line usually has a pressure difference between the pressure after filtration and the pressure before filtration at about 5MPA, and the filter needs to be replaced. In addition, the filter is usually replaced. First, the filter to be replaced is filled with slurry, and then exhausted through the exhaust hole. In the process of replacing the filter, the most important thing is to grasp the speed of switching to avoid shutdown due to loss of pressure.
4 Recovery screw

The recycling screw completes the recycling of waste edges and waste cloth. Pay attention to the following issues during the recycling process:

1 During the recycling process, the colors must be the same and the recycling must be uniform.

2 Monitor the temperature of the recovery screw to prevent temperature changes from causing damage to the recovery screw.

3 There must be no water in the non-woven fabric during recycling.

4 Never allow hard objects such as metal to enter the screw during recycling to prevent damage to the screw.

5 Metering pump

Precise measurement, uniform and continuous delivery of the spinning solution and a certain working pressure to ensure that the spinning solution passes through the spinneret smoothly. Gear pump structure.
Pump volume 1 line 150 cubic centimeters per revolution

1 line 250 cubic centimeters per revolution

2 lines 150 cubic centimeters per revolution

Line 3 currently has two metering pumps, which increase the production speed and can effectively adjust the weight of the left and right widths.
3 spinning box
Spinning box function: A insulation function

● As the base of spinning components

● Make the melt pressure uniform and flow evenly to the spinneret

4 spinneret

The structure includes-filter screen, distribution plate, spinneret aperture is usually 0.45mm.
Function: A filter melt

1 Make the melt fully mixed

2 Distribute the melt evenly to each spinneret hole of the spinneret, and ensure the pressure and the same outlet speed.
3 Make the melt form a trickle. Three cooling drafting, laying net
2 cooling draft
Process control point: A wind temperature 15-20 degrees

● Stable wind pressure

● Even at each point of the wind network, the air is evenly discharged and the pressure is stable. Honeycomb panel structure: honeycomb (hexagon 4mm)
Wind net surface net (80 mesh plain weave)
The upper and lower air ducts are connected with airbags, and the airbags cannot leak, so as not to affect the thread. In addition, the airbag pressure is not easy to be too high to avoid the airbag rupture.
3 hot press roll

The main function is to stabilize the fiber web.

Temperature control: A. The temperature of the electric heating surface is uneven, the middle is higher than the two sides.

1 Control the surface temperature at 80-140 degrees

2 Pay attention to the influence of speed on the surface temperature of the pressure roller

3 If the temperature is too high, it is easy to crack in the middle
Four hot rolling mill
                     1 Function: A Reinforce the fiber mesh into a usable non-woven fabric with good physical properties
1 Make the non-woven fabric have a good feel and gloss

2 Further improve the physical and mechanical properties of the fiber

2 Process control points: A hot rolling pressure 3-7MPA
B Hot rolling temperature 135—155 degrees

3The influence of pressure and temperature on non-woven pull

4Safety: A. Protect the hot roll, and never allow hard objects such as metal to pass through the hot roll

B Personal safety, avoid debugging or other handling of the roll during the operation of the machine.
Five rolls

During the rolling process of B, tension control:

● The tension increases within a certain range, the diameter of the cloth roll decreases, and the width shrinks

● If the tension is increased within a certain range, the tension can be increased. The actual need of the above tension is summarized in actual production to ensure quality.
C During the production process, pay attention to always check the width and roll length

D Paper tube and non-woven fabric roll should be aligned

E Pay attention to the inspection of appearance quality: dripping, broken wire, tearing, etc.

F Pack according to production requirements, pay attention to tidy and strong packaging

G Sampling test for each batch
B production speed:
                  Production constant = volume of metering pump * number of pumps * melt density * pump efficiency / production width

3-line metering pump volume: 150 cubic centimeters per revolution Melt density: 0.75 grams per cubic centimeter
The amount of change in pump efficiency needs to be obtained according to the actual situation. Net speed = constant * pump speed / gram weight
C theoretical weight:

Theoretical weight = gram weight * width * roll length pay attention to the use of units
Seven functional non-woven fabric

● Hydrophilic-hydrophilic masterbatch, hydrophilic agent
● Water repellent-jellyfish pellets

● Anti-aging-anti-aging masterbatch

●  Antistatic-masterbatch, antistatic agent

● Antibacterial and insect repellent-masterbatch
1. The definition of non-woven fabric: (more formal name non-woven fabric) a cloth-like material made of directional or messy fiber network, it is the application of fiber friction, self-adhesive force or external adhesive adhesion Force or two or more forces combined together.
Classification: 1 Dry-laid nonwovens: (mechanical reinforcement: needle punching, stitching, spunlace)
(Chemical bonding: spraying, foam)
(Heat bonding: hot melt, hot press)
● Polymer direct web method (meltblown, spunbond, film split)

● Wet method: round net, needle net
An introductory explanation of the concept, classification and development situation of non-woven fabrics
2. Raw materials: Note must be pp (polypropylene)
Explanation content: the concept of size, density, thermal decomposition temperature, melting point, molecular structure

Impact on production, concept of melting index, etc.
Third, the basic conditions necessary for the class leader: a sense of responsibility for various tasks, serving the public, and effectively coordinating the class
Various tasks, coordination and work between classes in the entire workshop, quickly master various production skills,
Achieve timely communication from top to bottom.
Give a specific explanation on the specific situation.
4. Production safety: personal safety, operation safety of the production line, use of equipment and tools on the production line
Safety, fire safety of the entire workshop.

Give specific explanations on the above safety requirements and easy problems.
5. Workshop environment. All colleagues in the workshop are required to fully realize the importance of a clean and tidy workshop environment, and focus on explaining the requirements of the workshop environment and its impact on the company’s development.
importance.

Six, S single-die head production line production process: the problems that should be paid attention to in the suction system (using negative pressure suction), such as the reasons for poor suction, the principle of suction, etc.
→Injection machine (when producing products with different performance and different colors, accurately measure and proportion each raw material and additives, and conduct preliminary mixing of raw materials and additives) attention to the problem, the working principle of the injection machine, and the true meaning of the raw material ratio , The input of the injection volume, the method and practical significance of the standard quantity, the precautions when the color difference occurs in the transfer, etc.
→Large screw (for further mixing of raw materials, high-temperature melting of the raw materials, so that the solid particles are converted into melt, so that the melt advances and generate a certain pressure) Note: the fluctuation of the rotation speed of the large screw when the current is normal Happening. Heating conditions in each zone, causes and solutions for looping, temperature setting requirements and meanings in each zone, screw structure and various indicators. →Melt filter (filtering out impurities that are not conducive to spinning in the melt), require each shift leader to grasp the method of replacing the filter and precautions as soon as possible, the structure of the filter and the pressure of the box before and after filtration Significance and impact on production.
→Measuring pump (accurately meter the melt flowing through the pump, and make the melt produce a certain working pressure forward). Pay attention to the problem. The output is mainly realized by changing the pump speed. The metering pump and the screw are in linkage working principle. →Spinning box (distribute the melt so that the melt is distributed as evenly as possible to the entire width). Pay attention to the problem, the temperature control of the spinning box and its impact on production, the melt distribution of the spinning box Principle, equal time and equal distribution.
→Spinning components (diffusion, filter, distribution plate, spinneret, distributing the melt, further filtering the melt, further distributing the melt, holding the filter, so that the fluid melt is extruded into the spinneret Silk). Pay attention to the problem. The spinning temperature and the replacement of spinning components must be mastered by everyone. The calcination, cleaning, ultrasonic, and assembly requirements of spinning components must be mastered by the team leader.
→Pull monomers (negative pressure to remove small molecules that are not conducive to spinning) pay attention to the problem, the impact of monomer pumping on production, and the problems that should be paid attention to in the monomer pumping system during production. →Side air cooling (cooling and stretching of high-temperature tow), pay attention to the problem, the air system has a great influence on the quality and appearance of the cloth surface, and macroscopically affects the uniformity of the cloth surface, the fineness of the fiber, the quality of the spinning, etc. The microscopic influences on the molecular orientation and crystallization of the fiber, the size of the air volume, the regularity of the wind, etc., have a particularly large impact on the quality of the fabric surface. Pay attention to summing up experience in the production.
→ Downdraft (stretching the tow, so that the tow is adsorbed on the netting curtain) pay attention to the problem, the influence on the spinning, size and uniformity of the cloth surface. →The drafting tunnel (flare mouth, where the fiber is cooled and stretched) pay attention to the problem, the bell mouth must be airtight and smooth inside in general. It has a great influence on the laying form of the tow, and the effect of dispersing the tow is achieved by the hole effect. In the production, attention should be paid to summarize the influence of the width of the tunnel on the laying.
→Pre-press heat roller (initially press the fiber web, make the fiber web flat, and seal the drafting tunnel). Pay attention to the problem, the effect of tightness, temperature and pressure on production and fabric surface, and the effect on cracking and discounting.
→Pay attention to the problems of the netting curtain (supporting the fiber web, conveying the fiber net), the influence of the density and tightness of the netting curtain on the drafting, the problems that easily occur in the production process, the installation method, the cleaning of the melting point, the protection of the net curtain, etc.

→Hot rolling mill (reinforcing the fiber web) pay attention to the problem. The mechanism is to heat and press the fiber web, so that the fibers at the pressure point are melted and bonded to each other. The different temperature and pressure required to produce different products are different from the temperature and pressure to the cloth. Strong influence, the basic structure of the rolling mill,
Easy-to-produce problems, cross-meaning methods, and different touch requirements for different customers.
→Hydrophilic device (adding hydrophilic treatment to the products produced). Pay attention to the problem, the working principle of the hydrophilic device, the requirements for the production of hydrophilic products, the basic type of hydrophilic agent, the hydrophilic effect, etc. →Winding machine (cutting and winding the product according to customer requirements). Pay attention to the problem, master the operating procedures of the winder, the adjustment of the width and tension, and the different diameter and tightness requirements of the customers for the cloth rolls.
→Packaging (package the product according to customer requirements). Pay attention to the problem, the on-site hygiene is absolutely clean and tidy, and truly understand the packaging requirements of each customer. Give specific explanations on the precautions of each part.
Seven, quality problems and solutions that often occur in production.
● Abnormal spinning, broken filament, melting point, etc., influencing factors, raw materials, wind system, temperature
Wait, do a specific analysis.

● The appearance of the cloth surface, there are many cases, the thickness of the silk, the uniformity of the cloth surface such as thin spots,
Uneven thickness, thin and thick cloth surface, influencing factors, three wind system, spinning temperature
The influence of pressure, the influence of drafting tunnels. Make a specific analysis.

● Influencing factors of the physical properties of the cloth (strength, elongation, hand feel), mainly include hot rolling, the degree of drafting of the fiber, and the influencing factors of the degree of drafting include temperature, stretching speed, cooling, etc. Make a specific analysis.
8. The issue of batch transfer in production,
● speed, and the problems that should be paid attention to in the process of batch transfer.
● The conversion between different colors, pay attention to the problem, the cleaning of the masterbatch, the color saturation
Reconciliation time, color coloring time, injection volume input, color matching method, factors affecting color change, color monitoring in the production process, the length of the transition time of various colors, the appropriate sequence of conversion between different colors .
Give specific explanations on the above issues.

9. Production methods and performance of various special performance products.
Flame retardant non-woven fabric, anti-aging non-woven fabric, anti-static non-woven fabric, antibacterial non-woven fabric, water-repellent non-woven fabric, hydrophilic non-woven fabric, soft non-woven fabric, etc.
Make a specific introduction,
10. Record and data conversion of various forms in production,



B. The various meanings of the production order, the calculation of the roll weight and the length of the roll, the filling method and actual meaning of various record sheets, the requirements and records of the weight, the weight test and the calculation method and meaning of the record.
C masterbatch, calculation of the amount of masterbatch required when producing various products. 11. Meltblown non-woven fabrics,
Superfine staple fiber, illustrated in the illustration.
12. SMS production line