Pressure-resistant screen changer

Product Name: Compression Screen Changer

I. Core Functions and Working Principles

Core Functions:

1. Continuous Filtration under High Pressure: In the high-pressure (usually 10 - 50 MPa) melt flow at the extruder outlet, the melt is forced through a high-precision filter screen to effectively intercept solid impurities such as carbides, gel particles, metal chips, and unmelted materials, ensuring the purity of the discharged material.

2. Screen Changing without Stopping the Machine: When the screen is clogged and the head pressure rises to the set value, the screen-changing slide or sleeve is driven by the hydraulic system.Instantly (0.1 - 2 seconds), the working position of the clogged dirty screen is moved out of the melt flow channel, and at the same time, the new working position with a pre-installed clean screen is moved in. Throughout the process, the melt flow is not interrupted, and production continues without interruption.

3. Stable Extrusion Pressure and Quality: Through fast and smooth screen-changing actions, the fluctuations of melt pressure and temperature are minimized, avoiding quality problems such as broken strips, uneven thickness, and decreased output caused by screen changing.

II. Main Structural Components

• Ultra-high Pressure Heavy-duty Machine Body: Made of High-quality alloy steel (such as 34CrNiMo6) After precision machining and heat treatment (quenching and tempering, nitriding), it has extremely high Fatigue resistance, creep resistance, and corrosion resistance and can withstand high temperature and pressure for a long time.

• Hydraulic Drive System:

  • Hydraulic Cylinder

• Screen-changing Slide (Core Moving Part):

  • Materials and Processes: Made of Special high-temperature alloy steel and the surface is subjected to Ultra-hardening treatment (such as boronizing, hard chrome plating) and High-precision grinding to ensure smooth sliding, wear resistance, and reliable sealing under high temperature and pressure.

  • Heating and Temperature Measurement: Built-in Heating rods and thermocouples to achieve precise control consistent with the machine body temperature and prevent the melt from cooling and solidifying at the slide gap.

• High-efficiency Sealing System:

  • Multi-layer Combined Sealing: Made of "Metal Sealing + Flexible Graphite Sealing + Spring-energized Sealing" and other multiple sealing combinations to ensure absolutely no leakage for a long time under a high temperature of 370°C and a high pressure of 50 MPa.

III. Core Features and Advantages of the Product

• Extremely High Reliability and Safety: Designed specifically for extreme working conditions to prevent Melt leakage (material running out) major safety accidents caused by material fatigue or sealing failure, ensuring the safety of personnel and equipment.

• Excellent Filtration Effect and Stability: The flow channel design is optimized, the filter screen area is large, the dirt-holding capacity is strong, and the screen-changing process has minimal impact on the melt pressure, temperature, and output, resulting in highly consistent product quality.

• Long Service Life and Low Maintenance Cost: The key components are made of top-grade materials and processes, with a long design life. The modular design makes maintenance simple, and the main sealing parts can be replaced online.

• Wide Process Adaptability:

  • Suitable for almost all plastic granulation processes: Such as granulation of new and recycled materials of PP/PE/ABS/PET/PA/PC, etc., filling modification, cable materials, and masterbatch production.

  • Suitable for High-viscosity Materials: Such as UHMW-PE, TPU, highly filled materials (calcium carbonate, glass fiber).

• Energy Saving and Efficiency Improvement: Screen changing without stopping the machine avoids the huge energy and time waste caused by traditional screen changing with machine shutdown, such as heating up, cleaning the machine, and leading in materials, significantly improving the equipment utilization rate and comprehensive production capacity.

IV. Key Application Scenarios and Technical Parameters

• Typical Application Scenarios:

  • Plastic Recycling Granulation Line: Filtering impurities such as sand, metal, and charred materials in recycled materials, it is an Essential equipment for producing high-quality recycled particles.

  • Modified Plastic Production Line: Filter glass fibers, filler agglomerates and gels produced during the manufacturing process.

  • Color masterbatch and functional masterbatch production line: Ensure uniform dispersion of pigments or additives and filter out coarse particles.

  • High - end special material pelleting: Such as materials with extremely high purity requirements, such as medical devices and auto parts.