Pneumatic discharge control partially filled TF-PNA

The reliable discharge control for wastewater and rainwater

Precise and easy to maintain system

The fast, almost self-cleaning and remotely controllable butterfly valve with pneumatic actuator is based on the flow measurement integrated in the system and limits the flow to an arbitrarily adjustable quantity. As long as the maximum flow is not reached, the flap remains open, while the flow measurement system measures precisely even when partially filled. The system is installed wet in wastewater applications or fitted into a closed pipeline. Due to its easy disassembly and the maintenance opening, the partially filled pneumatic flow control is extremely easy to maintain.

Wet installation and dry installation

The system is available in two designs; firstly for wet installation, whereby the outflowing medium flows from the flap into the open shaft. Secondly for dry installation, where the throttle valve is located in a housing which is connected to the drain pipe of the building. In this case, the medium is guided through the building in a closed system.

Direct drive and scissors drive for closing the control flap up to 10m pre-pressure

The control flaps of the pneumatic discharge control are mechanically designed to close tightly in the standard version up to 4m (and as an option up to 10m) water column. This eliminates the need to install an additional knife gate valve. For the larger nominal diameters from 600mm upwards, the control valve is driven with a progressive transmission (scissor drive) so that the valve closes with even greater force.

Pneumatic discharge control partially filled TFPNA as rainwater basin control in the sewer
Shear drive pneumatic discharge control for large flow rates and high inlet pressure
TFPNA dry installed with closed maintenance flap
TFPNA dry installed with opened maintenance flap
Partially filled pneumatic flow control TFPNA with suspension adapter

Technical information

ATEX Approval

  • Control damper: ATEX Zone I
    Maintenance opening: ATEX Zone I
    Piping: ATEX Zone I

Nominal width Design Control damper Direct drive

  • NW200 to NW500

Nominal width Design Control damper blade Shear drive

  • NW600 to NW1200
  • The control flap is located immediately after the flow measurement. This allows it to react quickly to changes in flow rate and can also maintain the programmed control value with the smallest deviation and delay time.
  • For the comparison with a knife gate valve flow control, the rule of thumb 1 to 10 can be used: Whereas a knife gate valve can move to 100 individual positions in stages, the pneumatic flow control system, thanks to its infinitely variable pressure control, can achieve at least 1000 individual positions – resulting in a massively higher control accuracy.

The control system of the pneumatic discharge control contains a touch display with zoom and wipe function as well as a data logger and a local small DCS for use with a web browser, which can be accessed in the local network or, if desired, via Internet. In addition to the versatile interfaces, the small DCS or the web server can also be integrated and displayed in the customer’s process control system.

Included as standard with modem for using all mobile networks up to 4G/LTE, Fixnet Internet connection and VPN technology

  • Signal outputs: 4-20 mA: instantaneous flow rate and set control value
  • Digital (active/passive): Flow counter and 2x fault
  • Signal inputs: 4-20 mA: set-point control value
  • Digital (potential-free): OPEN (remote); CLOSED (remote); AUTOMATIC; MANUAL START CLEANING;
  • Communication: RS485 (Modbus RTU/ASCII), RS232, Ethernet (Modbus TCP) Connection via Internet/VPN.
  • VPN connection for remote maintenance with STEBATEC(Internet connection with STEBAmobile possible)

Connection diagram on request.


The precise and maintenance-friendly solution

  • Control flap remains open in dry weather, while the flow is precisely measured even when the system is partially filled
  • Controls with high precision, shortest reset times and no running time limit
  • Pneumatic drive is better suited for the wet ATEX environment than an electric drive, for example
  • The throttle value can be variably parameterized/adjusted over the entire discharge spectrum
  • The control is remote controllable and compatible with all commercial process control systems
  • Measures the flow rate with a maximum of 1% deviation from the measured value
  • Combined flow measurement and control system incl. calming sections with minimum space requirement
  • Detects soiling and discharges it selectively (flush function, attachment discharge)
  • Throttles with an emergency program in case of power or device failure more
  • Is easy to maintain and can be disassembled/opened for cleaning without tools
  • Works with a standardized, mature control program
  • The units can be installed dry or wet


Why pneumatic control flap or pinch valve instead of knife gate valve?

  • Air in the pipe apex can escape
  • Speed: Open to closed in 3 seconds
  • Accuracy: Pneumatic drive adjusts very finely, while plate makes large movements compared to
  • No emergency power generator necessary for emergency position in case of power failure, as the system continues to operate with residual pressure in the compressor
  • No wear of the spindle and no sudden jumping behaviour
  • No electric drives in the hazardous area

References to this product

Let us advise you.

  • This field is for validation purposes and should be left unchanged.
Share this page …
Subscribe to our newsletter!

Let’s stay connected! Subscribe to our STEBAletter and receive regular news about our projects and activities.

Mattenstrasse 6a
CH-2555 Brügg

T +41 32 373 15 71

Heilbronner Straße 150
D-70191 Stuttgart

T +49 322 2109 3142

Follow us …

Copyright 2020 © STEBATEC