Polypropylene（pp） Woven Bags are widely used in different sectors. Aside from its use in agricultural products packaging, PP woven bags are used in cement bag packaging, food packaging, tourism, and various households. PP woven bags contain strips or threads that have been incorporated in two directions (warp and weft) to create light and durable, heavy-duty materials.
PP is the primary material used in producing woven bags. It is a slight transparent semi-crystalline thermoplastic with lasting durability, high water-resistant, and high melting point.
Polypropylene woven bags are an excellent alternative to other bags because they are healthy, light-weight, and non-staining. They are made to endure weighty materials and can be used again. Besides, they are porous with a layered film and can take a high processing temperature with a melting point of 167oC. They are also resistant to stress and cracking.
Process of Manufacturing PP Woven Bags
PP Woven Bags are generally made and printed regarding customer’s requests. The end customers get novel kinds of concealing mixes and Plans in the Printing of these Bags to pass on the message(s), characteristic(s), sum and quality-related nuances and managing bearings, etc. For specific kinds of unequivocal applications like filling of Hydroscopic Materials. For instance, Synthetic compounds, Manures, Food Items, etc., these Woven Bags are overlaid moreover. The Way toward assembling PP Woven Bags incorporates the accompanying three phases:
•Manufacturing of Tape
•Ousting of film
•Quenching of film
•Slitting of film
•Orientation of tapes
• Strengthening of tapes
•Winding
Ousting
The route toward assembling PP woven bags incorporates mixing crude materials beginning with PP or HDPE pellets and various added substances, ousting the natural materials into a yarn PP pitch is warmed with a sensor of CaCo3 and conceal, mellowed and removed as a level film. It is then cut into tape yarn by the cutting unit and expanded and strengthened. At that point, a take-up winder winds the warmth arranged tape yarn onto a bobbin.
Meshing
Meshing the yarn into a piece of texture is a cycle like the weaving of materials. These levelled tapes are then woven into an indirect surface by a Round weaving machine. As needs are woven roundabout texture is then cut into the required estimation. String from the bobbin in the round loom’s creel stand is woven into cylindrical Material The Meshing of Raffia Tapes into Fabrics is completed in Roundabout Weavers, produce Roundabout Material of needed Width. The route toward Weaving is Programmed and Persistent in nature. Amounts of Roundabout Weavers introduced to coordinate the Viable Yield of the Raffia Tape producing Plant. The Material conveyed by each loom is continually curved on Pivoting Lines.
Completing and Sewing
The Moves of Woven Material are made to the Completing and Sewing Part of the Unit. The fabric is cut into needed size and then printed. Subsequent to printing the cut pieces are sent for sewing. Going before the sewing of the Material, a valve is made in one corner of the cut piece, as indicated by the Clients particular. The Woven Sacks went through the Quality Control Test are bundled in 500 or 1000 Nos. Furthermore, pushed on a Bailing Press. The crushed Woven Sacks are wrapped, bundled, stuffed and dispatched. The Quality Control takes a gander at are conveyed at every single movement to keep away from excusals. The boundaries relating to the Weight, Denier, Blasting Strength, etc. are painstakingly clung to…
There are three main types of woven bags. These include:
● Plastic Woven Bags
● Composite Plastic Woven Bags
● Various Woven Fabrics
Plastic Woven Bags
The plastic wooden bags’ journey begins from a woven fabric which involves weaving many threads or tapes in two directions. The production of PP woven bags is in three phases:
● Printing
● Cutting
● Sewing
Depending on the machine used, you can print before cutting or vice versa. Regardless, an automatic cutting and sewing machine can do all the work. The device can process up to 45 bags per minute, and the cutting length is flexible. Also, the stitching can be single or double.
The woven fabric can form a tarpaulin, woven bags, container bags, valve bags, etc. Woven fabric usually have frays at the edges. So, the bag can be made after hemming bonding.
Technical Indicators of Fabric Woven Bags
Things to look out for in the production of standard woven bags include:
● Durability
● The bottom stitching direction
● Hemming edge direction breaking force
● Printing ink clarity and smoothness of other parts of the bag
● Layout position accuracy
● Stitching method
● The gaps in seaming
● Thread breakage
● Lack of stitches
Composite Plastic Woven Bags
Composite plastic woven bags are produced with wooden fabrics covered in compound materials and paper mixed to form barrel fabric. The resulting sheet material can be cut, printed upon, sewed, and turned into ordinary sewing bottom bags. It can be hit, folded, cut, printed, and stitched to produce cement bags.
The acquired sheet fabric can be stitched, tied up, imprinted upon, cut, fixated, and turned into adhesive bottom bags. Similarly, the Material can be fused, folded, and transformed into tarpaulin and absorbent textile. Flat sheet cloth and other round fabrics can be covered and uncovered to produce canvases and filter fabrics.
The logic behind Composite Bag Production is its Make-up Materials.
The principle of covering up materials is to coat the wax on the bottom of the Material’s woven cloth in a molten state. This molten resin is the only coated Material on the woven fabric immediately cooled to produce a two-hued woven cloth. There may be a situation where the molten resin paper is placed between woven cloth and plastic film during the mixture, resulting in a three-in-one woven cloth coating. In such a process, the molten resin film is coated on both sides of the tube cloth.
The coated woven fabric can be printed, cut, and stitched to form a coated tube cloth. This cloth can then be used to make a series of bag types, while the coated Material can be rolled up into a tarpaulin.
Various Woven Fabrics
Plain woven fabric and cylindrical cloth can be coated and uncoated to form tarpaulin, filter cloth, and valve bag.
Brief description of the plastic pellet manufacturing process
Add an adequate proportion of polypropylene powder, several preservatives, activated calcium into an enhanced blender in series, and stir in succession for a certain period. Then, put them into the hopper, and move them into the feeding screw. Once they are in the barrel, they can be melted and extruded through a heated chamber by a screw. The material strip is allowed to cool down and moulded by the water tank, resulting in moisture absorption by the absorption fan.
Cooling
At this stage, the material garb enters the pelletizer to cut the plastic pellet, which the vibrating screen will screen. After that, the shell will be moved by the conveying belt into the boiling bed to cool down until it is solid enough to be in the material tank. The Material gets sucked into the storage container by the feeder. After passing through a thorough inspection, the next is quantitative packaging, which performs the full production procedure.
The Process of Making Plastic Flat Yarn – Brief Introduction
The first production step of PP woven bag is flat yarn drawing. It determines PP woven bags standard, and it makes the raw Material of PP woven fabrics. They are manufactured with polyethylene through melting extrusion by the heating valve at 190-250°C and the screw and barrel’s mutual shear. After that, the sheet is cut into long pieces by the blade. The core silk is then straightened out in a high-temperature oven until it turns into a flat fibre.
The obtained flat yarn is heat-set on the hot roller, contracted under the condition of low friction speed, and refined by the cold roller at low temperature, and finally rolled and formed by the disc-differential tension winding system.
The primary process of flat yarn includes material modification, mixing, colouring, filling, preparation, anti-ageing, temperature controlling during extrusion, pressure and flow regulation, rheological extrusion, power consumption, and production rate. https://www.wovenpp.com/production-process-index-of-flat-yarn-for-plastic-woven-bag.html
Four Primary Technical Variables of Flat Yarn Production
The technical indexes of the flat wire production process are in four main categories:
● Physical and Chemical Modification: This involves blending modification, mixing ratio, adding a certain amount of functional preservatives, mixing ratio of recycled natural resources.
● Physical Rheological Indicator: This features mainly draft ratio, blow ratio, inflation ration, and contraction ratio.
● Mechanical Performance Indicator: This encompasses breaking force, relative breaking force, elongation at break, linear speed, linear density deviation.
● Tolerance Size Index: This mainly concerns the flat wire thickness and width.
Brief Description of the Circular Weaving Fabric Base Process
The first step is to stretch the warp yarn from each row of yarn spindles on the warp frame, which will produce the weft yarn and the warp yarn. Put the weft yarn into the shuttle magazine. Once the machine is put on, the shuttle will be driven by the propelling device to make a circular motion under the warp yarn supply system’s close cooperation and the shutting pushing device.
The next step is to weave into a rod-shaped flat fabric. Here, the mesh is pulled upward by the traction device on the top of the loom. After going through the guide roller, it is wound by the winding machine behind the warp frame. When the helical circumference reaches 1.2 meters, it is removed and transferred to the next stage.
Conclusion
Aside from the cement, agricultural, and food industry, PP woven bags are also used in households in packing items. Despite its use widely, not many people know the amount of effort put into making these bags. The process looks tedious, but with patience and practice, it becomes a walk in the park.
