Valve bag paper bag machine: core equipment and application analysis of powder and granular material packaging

From flour mills to cement plants, intelligent valve bag production lines are reshaping the way powder and granular materials are packaged.

In modern industrial packaging, valve bag paper bag machines have become core equipment for packaging powders and granular materials. In flour processing workshops, 25kg bags of flour are precisely filled and sealed by fully automatic valve bag packaging machines. In cement plants, high-strength reinforced paper valve bags churn out 10-32 bags per minute. In chemical warehouses, corrosion-resistant paper-plastic composite valve bags securely protect various fine chemical raw materials.

With the increasing requirements for environmental protection and the popularization of automation technology, traditional sewn bags are being gradually eliminated due to defects such as high pollution and easy leakage. Valve bags have been widely used in many industries due to their advantages such as one-time molding, fast loading speed, high firmness, moisture-proof and leak-proof, and environmentally friendly and recyclable .

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Working principle and classification of valve bag paper bag machine

The valve bag paper bag machine consists of two core parts: bag making equipment and packaging equipment. In the bag making stage, the fully automatic paper bag machine starts with the roll paper and goes through the following processes: folding, forming, bag cutting, gluing, bottom folding, and bottom gluing, completing the production of valve bags in one go.

In the packaging process, the fully automatic valve bag packaging machine includes automatic bag feeding, bag suction, bag covering, quantitative packaging, bag transportation and other devices . It adopts weight measurement and controls the feeding speed through the output signal of the weighing sensor.

Based on the degree of automation, valve bag paper bag machines can be divided into two types: semi-automatic and fully automatic. Semi-automatic machines require manual bagging and are suitable for small and medium-sized production. Fully automatic machines automate the entire process, from bagging, metering, sewing, emptying, packing, coding, conveying, and palletizing.

According to structural functions, the mainstream equipment in the market includes: paper-plastic composite bag making machines , which are suitable for multi-layer composite materials; high-speed paper bag making machines, with speeds of up to 100-300 pieces per minute; and special paper bag production lines that can produce open-mouth bags and valve bags at the same time.

Analysis of application scenarios in multiple industries

1. Flour and food industry

Flour mills require packaging solutions that meet food safety standards . The valve bag paper bag making machine for this application features 304 stainless steel contact parts with a surface finish of 200 mesh or higher, ensuring smooth material flow and preventing microbial growth. Ultrasonic heat sealing technology seals plastic or PE bags to prevent contamination.

For materials with poor flowability, such as flour, the packaging machine utilizes a double-screw feeding design and gross weight weighing to achieve high filling accuracy of ±0.2%. Wuxi Maijie's LCS-FQ1550 series packaging machine can process 80-120 bags (25kg) per hour and is equipped with a negative pressure dust removal system to maintain a clean workshop environment.

2. Cement and building materials industry

Cement packaging requires extremely high bag strength and moisture resistance. Our environmentally friendly paper bag production line utilizes new high-strength reinforced paper, multi-layer kraft paper, and paper-plastic composite materials to complete bag production in a single step through multiple processes.

Cement valve bags offer significant advantages: compared to traditional sewn bags, glued bags offer greater durability and leak resistance , and are easier to transport in containers. The paper-sand composite cement bag machine is a dual-purpose machine capable of producing both sewn-bottom and glued-bottom bags, with a production speed of 10-32 bags per minute, significantly improving cement packaging efficiency.

3. Chemical industry

The unique characteristics of chemical raw material packaging lie in the diversity and high risk of these materials. Valve-type paper bag machines for this application require three key capabilities: corrosion resistance , high sealing performance , and explosion-proof design . Customized packaging machines can feature corrosion-resistant coatings and enhanced sealing devices, and are compatible with a variety of materials, including kraft paper bags, coated woven bags, and aluminum foil bags.

For ultrafine chemical powders, Shanghai Ruifeng's RF-C50 packaging machine uses negative pressure dust removal technology to effectively control dust pollution. By changing the feeding method, it can adapt to the filling and metering of materials from ultrafine powder to large particles, meeting the packaging needs of different chemical raw materials.

Key parameters and technical configurations for selection

Performance parameter benchmarks

• Packaging speed : Bag making machine speed is 100-300 pieces/minute; packaging machine speed varies significantly according to material fluidity - ordinary powder is 100-240 bags/hour, sticky powder is 80-120 bags/hour.
• Precision control : static accuracy 0.1%, dynamic accuracy 0.2%-0.3%, using Toledo sensor + UNIPULSE intelligent instrument system.
• Material adaptability : paper weight 30-80 g/m2 (high-speed paper bag machine); supports kraft paper/laminated woven bags/PE bags/aluminum foil composite bags, etc. (packaging machine).

Table: Comparison of main technical parameters of valve bag paper bag machine

Device Type	Bag making speed	Packaging accuracy	Power Configuration	Applicable bag type
High-speed paper bag machine	100-300 pieces/minute	-	6 kilowatts	Shopping bags, food bags
Fully automatic packaging machine	80-240 bags/hour	≤±0.2%	4-11 kW	Valve bags, open bags
Paper bag production line	10-32 pieces/minute	-	28 kilowatts	Paste bottom bag, sewn bottom bag
Paper-plastic composite bag machine	75 m/min	-	28 kilowatts	Multilayer composite bags

Core configuration considerations

• Control system : Japan Mitsubishi PLC programmable controller + touch screen human-machine interface, realizing parameter setting, fault alarm and remote monitoring.
• Drive system : servo motor + variable frequency speed regulation, such as the paper-plastic paper bag machine adopts high-precision servo control system to achieve stepless speed change.
• Dust removal design : Active return air dust removal device (air volume 800-2500m³/h), negative pressure dust suction port integrated into the feeding nozzle.
• Structural design : Modular steel structure, such as the main head of the paper-plastic paper bag machine is made of 45# steel plate (40mm thick) to ensure long-term operation stability.

Mainstream equipment and technology development

Bag making equipment

• Paper bag production line : completes the whole process of multi-color printing, tube making, cutting, sealing, pressing and stacking in one go, and supports open bag/valve bag dual-mode production.
• Paper and sand compound machine : innovatively realizes automatic warp and weft mesh laying + automatic paper loading/gluing/printing/perforation, with bag making specifications of 350-650mm2 in width.
• High-speed paper bag machine : adopts PLC programmable servo system, bag making length is adjustable from 150-400mm, and is set on a touch screen.

Packaging equipment

• Shandong Bensen 5-50kg packaging machine : modular design, optional gravity/spiral/belt feeding methods, equipped with chain conveyor + automatic sewing integrated system.
• Wuxi Maijie LCS-FQ1550 series : Equipped with automatic bag feeding, bag suction and bagging devices, the packaging speed is 3-5 bags/minute (25kg), suitable for the range of 10-50kg.
• Hangzhou Lianyou ZL-50 pellet machine : gross weight weighing, static accuracy 0.1%, vacuum dust removal system (flow rate 10-12m³/min).

Technology Trends

1. Modular expansion : By replacing parts, one machine can be used for multiple purposes. The paper bag machine can switch between producing sewn bottom bags and glued bottom bags.
2. Energy saving and consumption reduction : The host power of the new generation of equipment is reduced to 4-11kW (packaging machine), and the gas consumption is 0.2-0.6m³/min, which saves more than 30% energy compared with traditional models.
3. Intelligent control : Remote diagnosis system based on the Internet of Things, equipped with communication interface to realize network management.
4. Adaptation to environmentally friendly materials : Develop special models suitable for environmentally friendly materials such as water-soluble yarn composite paper, recycled paper, and degradable PE.

Selection Practice Guide

Industry customized solutions

Table: Key points for selecting valve bag paper bag machines in different industries

industry	Recommended device type	Key feature requirements	Typical Configuration Examples
Flour foods	Fully automatic packaging machine	Food grade stainless steel, high sealing	Ultrasonic heat sealing + negative pressure dust removal
Cement building materials	Paper bag production line	High strength, moisture resistance	Multi-layer composite of reinforced paper + automatic bottom pasting
Chemical raw materials	Explosion-proof packaging machine	Corrosion-resistant and explosion-proof design	Pneumatic bag clamp + anti-corrosion coating
Mineral feed	Large tonnage packaging machine	Wear-resistant structure, large capacity	Belt feeding + 2 tons/bag expansion

Case Study : When upgrading its packaging system, a cement plant selected a paper bag production line paired with an automatic packaging machine. The bag-making process produces high-strength three-layer kraft paper valve bags . The packaging process integrates automatic bagging, weighing (with 0.2% accuracy), and conveying and sewing . This increased cement packaging efficiency by 40% and reduced the bag breakage rate from 1.2% to below 0.3%.

Return on investment calculation

A standard valve bag paper bag production line (bag making and packaging) costs approximately 1.5 to 3 million yuan. For cement packaging, for example, traditional sewn bags cost 1.2 yuan each, while valve bags cost 1.5 yuan each. However, this increases filling speed by 50% (up to 200 bags per hour) and reduces labor by 60%. With this overall efficiency improvement, the payback period is typically 18 to 24 months .

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With the continuous innovation of technology, valve bag paper bag machines are developing towards multifunctional integration - new equipment has realized unmanned production from roll paper to finished bags ; intelligent control systems can monitor the status of the packaging line in real time through mobile phone apps; modular design allows the same machine to process different materials such as flour, cement, titanium dioxide, etc.

After a chemical company adopted paper-plastic composite valve bag technology, its product damage rate during transportation dropped from 5% to 0.8% . A flour mill saved 50,000 yuan in monthly labor costs by upgrading its packaging machines. These data demonstrate the economic value of valve bag technology.

The future of valve bag paper bag machines will be smarter, more environmentally friendly, and more efficient. When companies face the crossroads of equipment selection, they need to consider their product characteristics, production capacity requirements, and sustainable development strategies to choose a truly suitable valve bag technology solution. This is not only an upgrade in packaging technology, but also a win-win situation for production efficiency and environmental responsibility.