Analysis of the manufacturing process of bag making machine

In the modern packaging industry, bag-making machines are key production equipment. Their manufacturing process integrates technologies from multiple fields, including mechanical engineering, electrical automation, and materials science. The creation of a high-performance bag-making machine requires rigorous design, precision machining, system integration, and rigorous testing. The following is an analysis of the entire bag-making machine manufacturing process.

1. Design and development stage

The manufacture of bag-making machines begins with in-depth market research and customer needs analysis. Engineers must clearly define the target product's specifications, including the material type (e.g., PE, PP, composite film), bag size range, production speed requirements, and any special functional requirements (e.g., punching, handle installation, etc.).

During the design phase, CAD (Computer-Aided Design) and CAE (Computer-Aided Engineering) software were used for 3D modeling and structural simulation. Mechanical structure design prioritizes mechanical stability, motion accuracy, and long-term wear resistance. Drive system design involves the selection and layout of components such as servo motors, cylinders, and cams to ensure coordinated motion across all actuators.

Electrical control system design involves hardware selection (such as PLCs, human-machine interfaces, and sensors) and software programming. Control algorithms must optimize motion control logic to achieve precise timing coordination for processes like feeding, sealing, cutting, and punching. Modern bag-making machines often integrate IoT modules to support remote monitoring and production data management.

2. Raw Materials and Components Procurement

The materials required for bag making machine manufacturing mainly include:

• Frame structure: Made of high-quality carbon steel profiles and steel plates to ensure the rigidity of the entire machine
• Transmission components: including precision ball screws, linear guides, gear racks, etc.
• Power system: servo motor, stepper motor, pneumatic components
• Surface treatment materials: anti-rust paint, chrome-plated parts, engineering plastics
• Electrical components: industrial-grade PLC, inverter, sensor, wiring materials

All purchased parts are subject to strict quality inspection to ensure they meet design specifications and durability requirements.

3. Mechanical processing and manufacturing

The machine frame is machined using large CNC gantry milling machines and machining centers to ensure the flatness of the mounting surface and the accuracy of the hole positions. The machining accuracy of key components is required to reach the micron level, such as the flatness error of the tool holder mounting surface does not exceed 0.02mm.

The heat-sealing system is the core component of the bag-making machine. The sealing blade must be made of high-quality copper alloy with a Teflon coating. Heating uniformity must be strictly controlled during the process, with a temperature difference of no more than ±1°C.

The assembly of transmission components requires professional technicians using precision instruments such as laser alignment tools to ensure the parallelism and perpendicularity of each axis. Bearings are installed using a shrink-fit process to ensure accurate fit and long service life.

4. Electrical system integration

The electrical cabinet assembly adheres to industry-standard wiring specifications, with strong and weak currents separated to minimize signal interference. All terminals are crimped and permanently marked. The control system undergoes ground resistance testing to ensure compliance with safety standards.

Servo system debugging includes parameter tuning and gain adjustment to optimize motor response characteristics. Motion control programming involves multi-axis linkage algorithms to achieve precise positioning of material conveying, typically requiring positioning accuracy of ±0.1mm.

The human-machine interface is developed with a focus on ease of operation, providing functions for recipe management, fault diagnosis, and production statistics. The system integrates multiple communication protocols to support data exchange with upper-level management systems.

5. Final assembly and debugging

The entire machine is assembled in a modular manner: the frame and base platform are installed first, followed by the drive system, heat sealing device, feed mechanism, and receiving device. Dowel pins and precision bolts connect each module to ensure repeatable assembly accuracy.

Mechanical commissioning includes:

• Adjust the conveyor belt tension to avoid deviation and slipping
• Heat sealing pressure balance adjustment to ensure sealing quality consistency
• Cutter stroke adjustment to ensure thorough cutting without burrs
• Photoelectric correction system calibration to achieve precise tracking of the web edge

The no-load test runs each motion unit to check for abnormal vibration and noise. The loaded test uses actual production materials to verify the machine's operating stability at different speeds.

6. Quality Inspection and Performance Testing

The whole machine inspection is carried out in accordance with national machinery safety standards and industry technical specifications. Inspection items include:

• Static accuracy detection: measure the flatness and parallelism of each mounting surface
• Dynamic performance test: Evaluate vibration indicators under high-speed operation
• Heat seal quality verification: testing seal strength and tightness
• Electrical safety testing: insulation resistance, voltage withstand test
• Noise testing: assessing compliance with workplace noise standards

The continuous production test runs for at least 72 hours, simulating actual production conditions and assessing equipment reliability and stability. Key parameters are recorded during the test and a complete test report is generated.

7. Surface treatment and packaging

After testing, the equipment is thoroughly cleaned and treated for rust. Exposed surfaces are sprayed with protective paint in a color that complies with company standards. Moving parts are appropriately lubricated with grease to prevent oxidation during transportation.

The packaging is moisture-proof and shock-resistant, with corner protectors. Key components, such as precision guide rails and lead screws, are secured with dedicated fixtures to prevent shifting and damage during transport. Complete technical documentation, operating manuals, and spare parts lists are provided with the equipment.

The manufacture of bag-making machines is a systematic project, requiring precise control and rigorous quality inspection at every stage. Excellent bag-making machines require not only sophisticated manufacturing techniques but also a deep understanding of packaging processes. With the advancement of intelligent manufacturing technology, modern bag-making machines are evolving towards higher speeds, higher precision, and greater intelligence, providing more reliable equipment support for the packaging industry.

The bag-making machines produced through the above manufacturing process can ensure long-term stable operation, meet the production needs of various packaging bags, and create continuous value for customers.