Hydraulic non-stop screen changer

Product Name:Beltless continuous screen changer (also known as: belt filter, fully automatic belt filter machine)
Technical positioning:In plastic granulation production lineRevolutionary melt filtration solutionIt abandons the traditional circular single-piece filter and intermittent filter replacement mode, and adopts...Special porous sintered metal mesh belt or high-precision steel mesh beltAs a filter medium, throughContinuous, slow movement of the conveyor belt,accomplishTruly 100% uninterrupted, pressure-fluctuation-free continuous filtration and impurity removalIt is an ideal choice for ultra-long-term stable operation and high-quality production.

I. Core Functions and Working Principles

Core functions:

1. Absolutely continuous dynamic filtering:The filter belt is drivenContinue to move slowly(Speed ​​adjustable), fresh, clean filter material continuously enters the main filter zone, while areas clogged by impurities are continuously removed. Melt pressure, flow rate, temperature.Achieve zero disturbance。

2. High-efficiency fine filtration:useHigh-precision porous sintered metal (powder metallurgy) mesh beltorSpecial woven steel mesh beltIt has high and uniform filtration accuracy and can stably filter fine gels, carbides, unmelted matter, etc.

3. Automatic waste removal and self-cleaning:The dirty mesh belt section removed from the main filtration zone has its attached impurities and filter cake automatically removed by a scraper or high-pressure backflushing device and collected in a waste box. The process is fully automatic and requires no manual intervention.

4. Extremely long operating cycle:In theory, as long as the mesh belt does not break, continuous filtration can be achieved indefinitely, making it particularly suitable for...Materials with high impurity content (such as highly contaminated recycled materials)Or requireRunning continuously for weeks or even monthsThe production line.

Working principle (dynamic continuous filtering):
The special filter belt moves unidirectionally at an extremely slow speed (such as a few millimeters to a few centimeters per minute) under the traction of two sets of precision drive/tension rollers.

• Filtering area:The melt enters the screen changer from the extruder and is forced through under high pressure.A moving, clean conveyor belt areaImpurities are trapped on the surface of the mesh belt to form a filter cake, while the pure melt flows to the mold.

• Removal and Cleaning Area:The conveyor belt section, carrying impurities, slowly moves out of the high-pressure filtration zone and passes through...Automatic scraper or high-temperature, high-pressure gas/melt backflushing deviceThe solidified impurity filter cake is peeled off and falls into the waste collector below.

• Continuous supply:The cleaned mesh belt (or the consumed mesh belt) continues to move, constantly providing new clean filter surfaces for the filtration zone, while the used mesh belt is wound up and collected or recycled (depending on the design).

II. Main Structural Components

• Heavy-duty pressure-resistant housing:Made of high-strength alloy steel, with a precise design.Mesh belt guide rail and sealing surfaceThis ensures stable operation of the conveyor belt under high temperature and high pressure with zero leakage of the melt.

• Core filtration and transmission system:

  • Special filter belt: Core ConsumablesMostlyMultilayer sintered stainless steel powder metallurgy striporSpecial dense braided steel stripIt has high porosity, high strength, high dirt holding capacity and excellent creep resistance.

  • Precision drive/tension roller system:Driven by a servo motor or stepper motor, and equipped with a high-precision reducer and tension control system, it ensures that the conveyor belt moves at a constant speed and has stable tension.

• Automatic cleaning system:

  • Scraper device:A carbide scraper is used to scrape off the removed filter cake impurities by adhering closely to the back of the mesh belt.

  • Backflush system (optional):Use high-temperature inert gas or a small amount of cleaning melt to backwash the mesh belt pores for deep cleaning.

• Waste collection and disposal system:The sealed waste collection tank can automatically discharge solid waste residue on a timed or continuous basis.

• Intelligent temperature control and sealing system:

  • Multi-zone independent temperature control:Precise temperature control is implemented for the machine body, conveyor belt, and cleaning area, etc.

  • Special end face seal:Use on both sides of the mesh beltFlexible graphite, spring energy storage coil or magnetic fluidAdvanced sealing technologies are used to prevent molten material from leaking from the edges of the conveyor belt.

• Advanced control system:

  • Integrating PLC and HMI:Control the conveyor belt speed (which can be automatically adjusted based on melt pressure feedback), cleaning cycle, temperature, alarms, etc.

  • Stress monitoring and adaptation:It monitors the pressure difference before and after filtration in real time and automatically adjusts the conveyor belt speed to maintain a stable pressure difference.

III. Core Features and Advantages of the Product

• Ultimate production stability: Completely eliminatePressure peaks and valleys and temperature fluctuations caused by screen changes must be addressed to ensure extrusion output and product quality (such as bar uniformity and color).Absolutely stableIt is a powerful tool for producing high-end products.

• Unmanned, fully automated operation:The entire process, from filtration, screen removal, slag cleaning to waste discharge, is automated, greatly reducing labor costs and operational risks.

• Unparalleled continuous operation capability:Especially suitable24/7 uninterrupted productionUnder these operating conditions, there is no need for planned downtime due to network replacement, and the equipment utilization rate reaches its theoretical maximum.

• Excellent impurity handling capabilities:Its large effective filtration area and dynamic renewal mechanism enable it to handle materials with extremely high impurity content (such as heavily contaminated recycled film), whereas traditional screen changers may require frequent screen replacements.

• High economic efficiency in long-term operation:Although the initial investment is higher, it saves the cost of frequent filter replacements and downtime losses, resulting in a significant overall cost advantage during long-term high-load operation.

• Environmental protection and safety:Waste residue is automatically collected in a sealed container, ensuring a clean working environment; there is no risk of high-temperature molten material spraying.

IV. Key Application Scenarios and Technical Parameters

• Typical application scenarios:

  • High-quality recycled plastic pelleting:likeFood-grade PET bottle flakes, high-grade HDPE recycled materialsThe production line has extremely high requirements for stability.

  • Granulation of high-filler/high-impurity materials:likeHigh-filled calcium carbonate masterbatch, glass fiber reinforced modified material, and heavily polluted agricultural film recycled material。

  • Direct granulation (reactive extrusion) in large-scale polymerization reactorsIt requires absolute continuity and no interruption.

  • Special materials such as cable materials and medical catheter materials are extremely sensitive to pressure fluctuations.Production.

• Technical parameters (example):

  • model:BCF-250 (Compatible with screw diameter)

  • Design pressure/temperature:35-50 MPa / ≤350°C

  • Mesh belt type:Stainless steel sintered powder metallurgy belt

  • Filtration accuracy:40-120 micrometers (equivalent to approximately 150-400 mesh)

  • Belt width / effective filter width:For example, 150mm / 120mm

  • Belt moving speed:0.1 - 10 mm/min (infinitely adjustable)

  • Drive method:Servo motor drive

  • Control method:PLC fully automatic, differential pressure feedback adaptive control

V. Selection and Usage Considerations

1. Investment return analysis:The equipment cost is significantly higher than that of traditional hydraulic screen changers. It is necessary to consider one's own circumstances.Annual operating time, material impurity levels, and product added valueTo assess the investment payback period.

2. Material compatibility assessment:Materials with extremely high viscosity (such as UHMW-PE) or containing ultra-hard impurities (such as sand and gravel) may cause significant wear to the conveyor belt, and special consultation is required.

3. Key points of operation and maintenance:

   • Mesh belt installation and tension adjustmentThis is crucial and must be done strictly according to the procedures.

   • Regular inspectionScraper wearsituation andSealing systemstate.

   • monitorMesh belt consumption rateandWaste discharge statusThese are indicators of system health.