Application and development
With the continuous deepening of the process of industrial automation and the further attention to the quality of packaging, the requirements for woven bags are getting higher and higher, which are mainly manifested in: mechanical properties, that is, strong and strong, anti-falling, able to cope with bumps in long-distance transportation and barbaric loading and unloading methods.
Use performance, such as moisture-proof, good sealing, to ensure that the product will not be affected by moisture in the process of storage and transportation, no product leakage, will not cause loss.
In terms of automation function, it can be filled efficiently, quickly and accurately.
In response to the above requirements, plastic woven square bottom valve bags have been widely used in both demostic and abroad.
Mainly used in cement, lime, grain, chemical fertilizer, chemical raw materials, chemical products and other packaging.
At present, the production of square bottom valve bag equipment, one is the adhesive paste bottom bag-making equipment, the other made by the heat seal welding process.
The former machine has higher requirements for the thickness of woven fabric, which is higher than 110g/ m 2.
At the same time, expensive adhesive is needed to paste the bottom in production, and the production cost of single bag is high.
In contrast, the thickness requirement of heat seal welding equipment for woven fabric can be as low as 50-60 g / m2, and there is no adhesive, so the cost per bag has a competitive advantage.
As shown in figure 1, the bag-making equipment for heat-sealed welded square bottom valve bag.
The main feature of this bag-making equipment is non-adhesive hot sealing production, which can save expensive adhesive.
The heat seal welded bag is a low-cost PP woven bag suitable for automatic packaging using a polypropylene woven fabric with PE film coating and with the help of an innovative adhesive-free heat seal production process.
The upper and lower seals of the square bottom valve bags do not need any sewing thread and expensive adhesive, but use the coated woven fabric for stable thermal bonding.
The film at the bottom of the bag, as well as the cover of the valve opening plate and the sealing film, are softened by hot air and then thermally sealed together by pressure.
The way of the bag bottom and the valve port of the heat seal welding makes the sealing of the bag bottom and the valve mouth extremely firm, and the force of the whole bag body is uniform in the case of falling, which avoids the weak part of the sewing pinhole of the sewing bottom bag.
In the bag-making machine, the transmission of the bag is carried out through the permanent magnet chain, which not only does not damage the bag body, but also ensures the accurate position and synchronous operation in the bag filling and transportation.
Through the reasonable setting of the drilling device, the bottom seal of the bag and the valve opening piece are bonded to each other, and the edge of the valve port is more firm, which can ensure that the high-speed filling bag is more stable, and the bag body can be checked in advance by the built-in opening tool, which ensures the high quality and high yield of the heat seal welded square bottom bag.
The main results are as follows:
(1) the sealing performance of the heat-sealed welded bag is good.
First of all, the manufacturing process requirement of the heat-sealed welding bag is to use the PP woven tubular fabric with film coating to ensure the tightness of the bag body; secondly, in the processing process, especially at the bottom, the sewing pinhole is avoided and the tightness of the bag body is maintained.
In contrast, after the sewing bottom bag is filled, the package, especially the powder, is very easy to leak out from the seam.
(2) the characteristic of the valve bag is that the valve mouth closes automatically after filling the material, but there is a great difference between the hot air welding bag and the seam bottom in the tightness of the closure.
Due to the full filling of the heat-sealed welding bag, the valve pocket can be closed automatically, and if necessary, the valve pocket can be completely sealed by ultrasonic wave through hot air pliers or filling line, so as to completely eliminate leakage.
After this kind of square bottom valve mouth packing bag is filled, the brand information printed on the side and bottom is clear and easy to see, the bag body is clean and beautiful, and there is no stain caused by adhesive.
The main results are as follows:
(1) equipped with twin-roll micro-hole device, when cement and other powdered products are filled at high speed, the fine micro-hole can ensure that the air in the bag can be discharged quickly to achieve high-efficiency filling.
And because of the fine micro-hole and the configuration of two-way micro-hole roller, the leakage of powder filling can be avoided, and a good waterproof and moisture-proof effect can be achieved.
(2) the square bottom valve bag is rectangular brick after loading, the palletizing is neat, the number of stacking layers is high, it is easy to transport and convenient for mechanized loading and unloading and storage.
(3) the valve port of the packing bag can be used not only for manual bag insertion, but also for automatic bag insertion mechanized assembly line filling, even when filling powdery materials such as cement, the speed of automatic bag filling machine can greatly improve the production efficiency.
(1) the production of square bottom valve bag does not require expensive adhesive or sewing thread.
(2) the product quality is high, the breakage rate is extremely low, and the raw materials are saved to the maximum extent.
(3) compared with the production of sewing bags, it can save a lot of labor and reduce the cost of production management.
In recent years, with the rising prices of raw materials, the proportion of the cost of raw materials in the cost of the whole woven bag has become more prominent.
The hot seal welding square bottom valve bag only because of the above reasons, especially the low consumption of raw materials and no adhesive, the production cost is greatly reduced.
At present, due to the characteristics of the valve bag, it has been widely used in packing powdery items such as cement and chemical fertilizer, and it is the best powder packaging bag in the world today. it is expected that it will be widely used in chemical industry and other fields because of its superior performance.
Post time: Dec-22-2022