Labotek Con-Evator PGT Series
Compact and High-Performance Vacuum Material Conveying Systems
The Labotek Con-Evator PGT series consists of compact vacuum hopper loader systems developed for the reliable, stable, and controlled conveying of free-flowing plastic granules between injection molding machines, extrusion lines, and intermediate bins. The PGT series offers an ideal solution especially for machine-mounted applications and short- to medium-distance conveying requirements where simple installation and high performance are essential.
Con-Evator PGT systems are available in either a single-piece compact design or split configurations where the blower is separated from the hopper, allowing easy adaptation to different plant layouts and weight limitations. Thanks to their robust mechanical design, automatic filter cleaning, and advanced control unit, the PGT series stands out with low maintenance requirements and long service life.
General Operating Principle and Vacuum Conveying Technology
Labotek Con-Evator PGT systems generate vacuum inside the hopper using a side-channel blower driven by an electric motor. This vacuum enables the material to be conveyed from a granule container or bag into the hopper via a suction probe and conveying hose.
During the conveying cycle, the bottom flap remains closed to ensure stable vacuum formation. Once conveying is completed, the blower stops and the bottom flap opens under the weight of the material inside the hopper, allowing the material to discharge directly into the machine hopper or intermediate bin. If the material level is insufficient, the flap remains closed and a new conveying cycle is not automatically initiated, preventing overflow and irregular feeding.
Filter cleaning is performed automatically by reversing the rotation direction of the blower either before or after each conveying cycle. In configurations equipped with an optional blow-back valve, filter cleaning is carried out using compressed air without reversing the blower direction. This system extends filter lifetime and minimizes performance losses.
PGT Series Models and Technical Configurations
The Labotek Con-Evator PGT series consists of two main models:
Con-Evator PGT-I 4
Motor power: 0.4 / 0.5 kW
Installed power: 0.5 / 0.6 kW
Vacuum hopper volume: 8 liters
Noise level: 62 dBA
Conveying hose inner diameter: 32 mm
Standard hose length: 3 m
Net weight: 17.5 kg
Con-Evator PGT-II 6.1
Motor power: 1.3 / 1.6 kW
Installed power: 1.4 / 1.7 kW
Vacuum hopper volume: 16 liters
Noise level: 68 dBA
Conveying hose inner diameter: 38 mm
Standard hose length: 3 m
Net weight: 33.8 kg
All models operate with a three-phase 220–480 V, 50/60 Hz power supply and feature a 24 V control voltage.
Conveying Capacities and Distance-Dependent Performance Values
The conveying capacities of the Con-Evator PGT series are determined based on approximately 0.6 kg/l bulk density, free-flowing granules, and the assumption that the hopper is completely filled during each cycle.
Typical capacities for the PGT-I 4 model:
3 m vertical + 1 m horizontal: approximately 227 kg/h
3 m vertical + 12 m horizontal: approximately 173 kg/h
5 m vertical + 24 m horizontal: approximately 118 kg/h
Typical capacities for the PGT-II 6.1 model:
3 m vertical + 1 m horizontal: approximately 542 kg/h
4 m vertical + 24 m horizontal: approximately 363 kg/h
5 m vertical + 36 m horizontal: approximately 304 kg/h
Actual conveying capacity may vary depending on granule size, material density, number of bends, and hose length.
Filtration System and Automatic Cleaning
The PGT series features a dual-stage filtration system consisting of a disk filter positioned between the blower and the hopper, and a filter bag located in the lower section. This configuration protects the blower from dust and prevents particle emissions into the surrounding environment.
Filter cleaning is fully automatic and does not require compressed air in the standard configuration. For dusty or demanding applications, optional pneumatic blow-back valves, cartridge filters, and cyclone solutions can be integrated.
Control Unit, Programs, and Safety Functions
The Con-Evator PGT control unit offers four standard conveying programs:
P1: Filter cleaning with reverse air before conveying
P2: Filter cleaning with reverse air after conveying
P3: Filter cleaning using a blow-back valve
P4: Conveying with closed system and slide valve
Bottom flap position sensors, external level sensors, and dosing valves can be integrated into the control unit. The system is equipped with safety functions such as motor overtemperature protection, conveying alarms, and thermal protection.
Mechanical Design and Durability
The hopper body and critical mechanical components of the PGT series are manufactured from durable metal alloys to ensure long service life. The bottom flap is made of stainless spring steel and can optionally be supplied with a PTFE-coated version to prevent sticking caused by static electricity.
Thanks to its compact design, direct mounting on the machine is possible, minimizing the need for additional support structures.
Application Areas
Plastic injection molding machines
Extrusion and co-extrusion lines
Masterbatch and compounding plants
Intermediate bins and machine-mounted feeding applications
Short- and medium-distance granule conveying systems
Industrial Advantages
Compact and space-saving design
High and stable conveying capacity
Filter cleaning without compressed air
Low noise level
Easy installation and maintenance
Long service life and high process reliability
Up to 3 years warranty excluding wear parts
