mature program

For more than 60 years, SPÄNEX radial fans have been manufactured for various industrial applications. The many years of experience and the continuous further development form the basis for a mature and comprehensive delivery program of single-suction radial fans. A special focus of the development work of the last years was on the topic of energy efficiency and in this context the speed control by frequency converters.    

The power range of the program includes volume flows from 1,000 to 120.000 m³/h and total pressure increases from 1.000 to 10.000 Pa.

With several series and 20 nominal sizes up to a suction diameter of 1.250 mm, the entire spectrum of our requirements can be covered and the optimum fan can be selected for each individual case.

The fans are mainly used in the exhaust plants and dedusting systems produced and supplied by SPÄNEX, so that the in-house experience from practical use flow in the permanent further development for the improvement and optimization of the fans.

energy efficiency

The radial fan is the core component of any exhaust system in terms of energy-saving operation. The efficiency of the fan has a major influence on the power consumption and thus on the annual energy costs.

However, in the topic of energy efficiency not only the data of the fan is decisive, but also the other consumption-related factors must be included in the consideration:

  • the pipework system and
  • the operation of the plant.

According to our motto "everything from one source", our experienced sales staff will plan and dimension the pipework system for each individual application, so that the fan has to overcome lowest possible pipeline resistances at the given suction volume flows.

A further important contribution to minimising electricity consumption is the speed control of the fans via frequency converters. Due to the intelligent feedback control systems and control technology, the corresponding demand for suction power is recognized at all times and only the required suction power is provided via the control of the fan speed.

Further advantages of speed control via frequency converters can be seen in the following aspects:

  • fans starts without current peaks,
  • lower noise emissions.

materials that can be conveyed

SPÄNEX radial fans are suitable to convey clean air, dust-containing air and chip-/dust-air mixtures with low to high material charge. The chip-/dust-air mixtures of the following material can be conveyed:

  • wood
  • other biomass,
  • plastic
  • paper

practical examples

exhaust- and transport fan installed in sound insulation cabinets
Absaug- und Transportventilator eingebaut in Schallschutzkabinen
radial fan with direct drive during the assembly
Radialventialtor mit Direktantrieb während der Montage
exhaust fans sound-protected with belt drive
Absaugventilatoren schallgeschützt mit Riemenantrieb
transport fan with direct drive
Transportventilator mit Direktantrieb
2 radial fans NG 710
2 Radialventilatoren NG 710



For modern exhaust systems the SPÄNEX radial fans are components of dust collectors and filter units, i.e. they are installed directly into these devices. In the case of exhaust systems with larger air volumes, the radial fans are mainly positioned after the filter units (vacuum system). For only a few requirements, it makes sense to install the radial fans in the pipwork system in front of the filter devices (overpressure-system).

Also in case of pneumatic conveyor systems, the transport fans are usually placed in the clean air-side section of the pipeline.

Different running wheels are available for each of these individual applications:

  • closed wheels with backward bent blades: conveying purified air or dust-air mixtures with low material charge  
  • closed impellers with reversed blades: conveying material-charged air (dust or short-fibre chips with low to medium material charge)
  • open wheels with radial shovels: conveying material-charged air (dust, rough or long-grained shavings as well as chips with high material charge)

The casing and the running wheels are welded solid steel sheet constructions in a heavy design. The casings are reinforced with profile steel and lacquered as standard. At fans with belt drive, the fan and motor are mounted on a common base frame.

The running wheels are statically and dynamically balanced, so that a maximum of quiet running is achieved.

Three types of drive are used:

  • drive directly via motor shaft,
  • drive via coupling and
  • drive via V-belt

When conveying explosive gas-/and/or dust-/air mixtures the fans are equipped according to ATEX, among other things a spark protection at the inlet nozzles.

standard fans

Up to a nominal size of 400, standard fans with different running wheel assembly are available for different pressure levels. The casings and running-wheels of these fans are manufactured in larger series and can be mounted and delivered on demand at short notice. By the series production a particularly favourable price-performance ratio is achieved. Depending on the nominal size, on the installed running-wheels and on the pressure level, motors of the efficiency class IE 3 (optional IE 4) are used with performances between 2.2 kw and 18.5 kw. These are generally direct drives where the running-wheel is mounted onto the motor shaft.

The fans are supplied completely with suction- and pressure-side transitions including assembly rails.

For the standard fans the complete range of accessories is available.

SPÄNEX radial fans

[Translate to English:] Radialventilator mit Direktantrieb
Radialventilator mit Direktantrieb
[Translate to English:] Radialventilator, Nenngröße 800
Radialventilator, Nenngröße 800
[Translate to English:] 2 Radialventilatoren mti Direktantrieb während Montage
Überprüfung von 2 Radialventilatoren


  • counter flanges and transitions for suction side and pressure side
  • compensators
  • vibration isolation devices
  • wear protection for running-wheels and casings
  • sound-damping casing and/or sound insulating cabinets
  • speed control via frequency converter
  • monitoring for rotations, temperature and vibration
  • pipe sound absorber and splitter attenuator
  • explosion protection


  • solid design at highest quality level
  • requirement related running-wheel geometries
  • energy-efficient operation
  • standard use of IE 3 motors
  • long service life
  • powerful service