1. System Philosophy & Overall Architecture

Traditional material handling in plastics factories relies on individual loaders mounted on each machine. Every loader generates its own vacuum, draws ambient air through the material stream and discharges residual dust and warm air directly into the production hall. The result is a noisy, dusty and thermally unstable environment that compromises both product quality and operator comfort. The EXTRUTEX Central Conveying System reverses this paradigm.

At the heart of the layout is a single, high-capacity central vacuum unit (or a redundant pair of units) that serves every processing machine on the shop floor. Raw materials are stored in a battery of stainless-steel silos or day bins, optionally equipped with drying or crystallizing units. From these central sources, material is conveyed through a network of stainless-steel or aluminium pipes under continuous negative pressure. At each machine a compact, low-noise receiver (hopper loader) receives the material and discharges it into the machine throat on demand. Because the entire circuit is sealed, neither dust nor process heat escapes into the workshop.

The isometric construction layout typically shows a central control cabinet, a vacuum pump station, a bank of material sources, a multi-branch pipe network and a series of machine-mounted receivers. Pipe routing is carefully calculated for minimum pressure drop and maximum conveying distance—often exceeding 100–150 m for multi-storey or multi-building installations. Automatic pipe-cleaning cycles and line-purging sequences prevent cross-contamination when materials are changed.

2. Core Performance Characteristics

The performance advantages of the EXTRUTEX central system are both technical and commercial. They can be grouped into five principal benefits that appear consistently in customer feedback and internal testing data.

3. Detailed Technical Description

3.1 Central Vacuum Generation

EXTRUTEX employs high-efficiency side-channel or claw-type vacuum pumps selected according to total conveying distance, number of simultaneous receivers and material bulk density. Pumps are equipped with frequency inverters that modulate motor speed in real time, maintaining a constant vacuum set-point while minimizing electrical consumption. Redundant pump configurations with automatic change-over are available for 24/7 continuous operation. All pumps are mounted on vibration-damped frames inside sound-attenuating cabinets; residual noise at 1 m is typically ≤ 75 dB(A).

3.2 Material Sources & Storage

Material can be drawn from a wide variety of sources: outdoor aluminium or stainless-steel silos, indoor day bins, octabins, big-bags or directly from drying/crystallizing hoppers. Each source is fitted with a material probe or level sensor that communicates with the central PLC. Automatic source selection allows the system to switch between virgin resin, regrind and additives without operator intervention. Optional integrated drying systems use dual-bed desiccant dryers or infrared crystallizers to ensure that hygroscopic materials (PET, PA, PC, etc.) enter the conveying circuit at the required residual moisture level.

3.3 Pipe Network & Routing

Conveying lines are fabricated from stainless steel (AISI 304 or 316) or anodized aluminium, with smooth internal surfaces and large-radius bends to minimize abrasion and pressure loss. Pipe diameters range from 40 mm to 100 mm depending on throughput. Multi-branch manifolds are equipped with pneumatically actuated diverter valves that route material to the correct destination. Automatic line-cleaning (pipe-purging) sequences empty residual material after each conveying cycle, preventing colour or type contamination when recipes change.

3.4 Machine Receivers (Hopper Loaders)

Each processing machine is equipped with a compact receiver whose volume is matched to the machine’s throughput. Receivers are available in stainless steel or food-grade polymer construction and incorporate a high-efficiency filter cartridge that is automatically cleaned by reverse-pulse air. A level sensor (capacitive or optical) triggers the next conveying cycle when the material level falls below a pre-set threshold. Because the receiver is under continuous vacuum only during the short filling phase, energy consumption and filter loading remain minimal.

3.5 Vacuum Valves & Air-Suction Control

A critical component highlighted in the original construction layout is the vacuum valve. EXTRUTEX vacuum valves are compact, lightweight units fitted with an internal rubber diaphragm that guarantees absolute airtightness. The valve is installed in the air-suction circuit and is controlled by the central PLC. When a receiver calls for material, the corresponding valve opens, allowing vacuum to be applied only to that specific line. All other lines remain isolated, preventing unnecessary air leakage and maintaining system efficiency. The diaphragm design ensures reliable sealing even after tens of thousands of cycles and is resistant to the abrasive action of glass-filled or mineral-filled resins.

3.6 Central Control System

The entire installation is supervised by a programmable logic controller (PLC) of European origin, selected for its robustness and long-term availability of spare parts. The operator interface is a colour touch-screen HMI that displays real-time status of every machine: material loading, machine on/off status, material-shortage alarms, filter-cleaning cycles and vacuum-pump operating parameters. Recipe management allows the operator to assign specific materials and source silos to each machine with a few screen taps. Historical data logging and Ethernet connectivity support integration into plant-wide MES or Industry 4.0 platforms. Remote access via secure VPN is optionally available for factory-floor diagnostics by EXTRUTEX service engineers.

4. Operational Workflow

A typical operating sequence proceeds as follows:

1. The operator selects a material recipe on the central HMI and assigns it to one or more machines.
2. The PLC opens the appropriate source valve and the corresponding receiver vacuum valve.
3. The central vacuum pump accelerates to the required speed; material is drawn through the pipe network into the selected receiver.
4. When the receiver level sensor detects a full condition, the vacuum valve closes and the material is discharged into the machine throat.
5. A brief reverse-air pulse cleans the receiver filter; the line is optionally purged with clean air to remove residual pellets.
6. The cycle repeats automatically whenever the machine level falls below the set-point.
7. If a material shortage is detected at the source, an alarm is raised both on the HMI and, if configured, on the machine’s own control panel.

Because the vacuum is applied only to the active line, multiple receivers can be served sequentially or in carefully timed parallel groups without loss of conveying velocity.

5. Customisation & Options

EXTRUTEX recognises that no two plastics plants are identical. The system is therefore modular and fully customisable:

• Stainless-steel hoppers and receivers in any required volume and geometry.
• Integration of gravimetric or volumetric dosing units for masterbatch and additives.
• Inline metal detection and automatic rejection of contaminated material.
• Multi-component blending stations for complex recipes.
• Outdoor silo farms with pneumatic truck unloading and automatic inventory management.
• Explosion-proof (ATEX / IECEx) configurations for dusty or solvent-laden environments.
• Special abrasion-resistant pipe linings for glass-fibre or mineral-filled compounds.

All custom components are designed in Austria and manufactured under strict quality control at the Nanjing and Shanghai plants, ensuring consistent metallurgy, welding standards and surface finishes.

6. Technical Specifications Table

The following table summarises the principal technical parameters of a typical EXTRUTEX Central Conveying System. Exact values are project-specific and confirmed during engineering design.

7. Installation Layout Considerations

The isometric construction layout provided by EXTRUTEX engineers shows the recommended spatial arrangement. The vacuum pump station is ideally located outside the production hall or in a dedicated plant room to isolate noise and heat. The central control cabinet is placed in a clean, accessible area—often adjacent to the production supervisor’s office—so that operators can monitor the entire system at a glance. Material sources (silos, dryers, day bins) are clustered to minimise pipe runs. Machine receivers are mounted directly on the feed throat of each extruder or injection-moulding machine, with flexible hose connections that accommodate machine vibration and occasional repositioning.

Pipe bridges and overhead trunking keep the floor clear for forklift traffic and maintenance access. All valves, sensors and receivers are accessible from catwalks or portable platforms, facilitating routine filter changes and inspection. The layout also anticipates future expansion: spare pipe branches and electrical conduits are installed during the initial phase so that additional machines can be connected with minimal disruption.

8. Quality, Safety & Environmental Benefits

Because the conveying circuit is completely closed, ambient air does not contact the material stream after the material leaves the source silo. This eliminates the risk of moisture pick-up, airborne contamination and thermal degradation. Product quality—particularly critical for optical, medical and food-contact grades—is therefore protected throughout the handling process.

From a safety perspective, the absence of open dust sources reduces the risk of dust explosions and improves occupational hygiene. Centralised dust collection means that operators never handle fine powders directly. All electrical components are selected and wired in accordance with European machinery directives; emergency-stop circuits and interlocks are fully integrated into the PLC safety architecture.

Environmentally, the reduction in energy consumption and the elimination of local exhaust fans translate into a measurable lowering of the plant’s carbon footprint. Captured dust can be recycled or disposed of in a controlled manner rather than being released into the atmosphere.

9. Why Choose EXTRUTEX

10. Project Execution & After-Sales Support

Every EXTRUTEX central conveying project follows a structured engineering workflow:

1. Site survey & data collection – material types, throughputs, distances, machine list, existing infrastructure.
2. System design & 3-D layout – pipe routing, vacuum calculation, receiver sizing, control architecture.
3. Detailed engineering & bill of materials – final drawings, valve lists, electrical schematics.
4. Manufacturing & factory acceptance test – assembly and functional testing in Nanjing or Shanghai.
5. Installation supervision & commissioning – on-site support by EXTRUTEX engineers or certified partners.
6. Training & handover – operator and maintenance training, documentation package.
7. Ongoing support – remote diagnostics, spare-parts supply, periodic inspections.

Customers receive a complete documentation package that includes P&IDs, electrical drawings, operating manuals, maintenance schedules and recommended spare-parts lists. Software updates and recipe expansions can be performed remotely when the system is connected to a secure network.

11. Conclusion

In an increasingly competitive plastics-processing landscape, the ability to deliver consistent product quality while controlling energy costs and improving workplace conditions is a decisive advantage. The EXTRUTEX Central Conveying System addresses all three requirements simultaneously. By centralising vacuum generation, sealing the material path and placing intelligent control in the hands of a single PLC, the system removes dust, noise and thermal pollution from the production hall, reduces power consumption by up to half, and gives operators full visibility and remote control over every material movement.

Whether the plant is a multi-line extrusion facility, a large injection-moulding hall or a compounding operation handling dozens of formulations, the modular architecture of the EXTRUTEX system scales gracefully. Custom stainless-steel hoppers, abrasion-resistant pipework, integrated drying and dosing, and advanced recipe management ensure that the solution fits the process rather than forcing the process to fit the equipment.

Backed by Austrian design expertise and manufactured to exacting standards in Nanjing and Shanghai, EXTRUTEX delivers a reliable, future-proof materials-handling platform that protects product quality, lowers operating costs and elevates the professional image of the entire production facility. For plastics processors seeking a cleaner, quieter and more efficient plant, the Central Conveying System is no longer an option—it is the new standard.