maax® BF
Automation solution for backflush screen changer
maax® BF is Maag’s well-proven control system
for the fully automatic backflush screen
changers. It allows the processor of highly
contaminated polymer melts a simple handling of the backflush screen changer and a
fully automatic screen cleaning and manifold
use of the screens. The automation system is
particularly well suited for retrofitting extrusion lines with screen changers with backflush
function. Operation, control, and regulation
as well as monitoring of operating parameters
are simplified. Process and operation reliability
of the entire system are increased.
Your benefits
Simple and clear operation of filter and system functions
Increased productivity
Increased productivity through storage of recipes in parameter lists
Integrated temperature control of the system components
Rapid error detection via clear text messages
Scalable visualization of different operation parameters in a trend
maax® BF
Automation solution for backflush screen changer
Technical specifications:
Control cabinet:
Rittal system cabinet
Convenient and safe operation via color display with touch function and key
Operating voltage (standard):
3 x 400 V/N/PE
Control voltage:
24 VDC
Teleservice function for PLC program and visualisation
Solenoid valves:
24 VDC
Displacement transducer:
Online language changeover
Micropulse transducer with Profibus DB
Signaling of operating mode and plant status
Melt pressure:
DMS 3.3 mV/V
Anti-block mode with motion monitoring
Melt pressure measurement
Operating panel:
Touch Panel 10'', color
Recipe memory
Heating control for 8 heating zones
On the basis of a Simatik, the control system
maax® BF fulfils the requirements of simple
recycling plants up to process-constant direct
recycling applications, such as the processing
of PET bottle flakes to thermoforming sheet
on an extrusion line. Depending on the
specific needs, the extruder and melt pumps
can be incorporated in the control system.
Mode 1: Pressure-dependent piston positioning
In all commercial recycling filters, cyclical screen cleaning and screen
venting take place for functional reasons due to small amounts of
material from the main melt stream. By these volume losses a negative
impact on the process could not always be excluded in the past. The
new, dynamic piston positioning in Mode 1 constantly monitors the
maximum deltaP requirement of the user, in which the piston distances
and retention times are adjusted in a self-optimizing manner. This will
limit pressure fluctuations and prevent exceeding the permissible product tolerances.
Mode 2: Pressure-dependent volume control
maax® BF offers you a full service
Supply of all electrical equipment mounted in the control cabinet
Complete supply of the functional system
Screen changer integrated into your production line control system
Technical guidance and advice and process optimization
System commissioning and operator training
“Round-the-clock” service with short response times
Global contacts, see
Contact us at
The data and illustrations refer to the date of printing. Necessary changes can be made at any time without special notice. Maag´s products and processes are protected by IP rights.
CSC/BF-4F: For many years the benchmark
for cost-efficient and reliable filtration of
highly contaminated polymer melts. The fully
automated screen cleaning permits multiple
uses of the screen.
The new control guarantees an almost absolute pressure and throughput consistency in the process in conjunction with a conveyor stiff
extruder or an extrex® melt pump. Here, in mode 2 during screen cleaning or venting cycles the constant extruder or pump speed is temporarily suspended. As a result, the pressure reduction due to volume loss is
proportionally compensated by short-term speed increases. With a constant flow rate and melt pressure at the tool a consistently high product
quality is guaranteed. Thereafter, the control switches back to the
normal operation with constant speed of the extruder or melt pump.