Precision cleaning with compressed air –
Intermediate / blow-off box

Not only a hot wind for your processes, but precise and efficient parts cleaning!

The KNOTH SurfaceAircleaner and PrecisionAircleaner cleaning systems were the forerunners amongst the industrial parts cleaning systems with regard to two-dimensional as well as precise cleaning tasks with compressed air as the medium. Up to then, the area of intermediate cleaning had been a neglected topic: Manual workplaces with compressed air pistols were preferably used, larger production lines were equipped with inefficient, high-maintenance blast air systems, to be able to ensure at least surface cleanliness. By now, our intermediate cleaning systems and precision cleaning systems are part of the usual inventory at almost all larger automotive production lines.

No mixing of media, only air!

Highly precise, selective cleaning!

Small space requirement!

Short cleaning time!

The common name for our SurfaceAircleaner and PrecisionAircleaner cleaning systems worldwide is KNOTH “blow-off box”. This is proof for the worldwide brand awareness and function of our systems.

While our SurfaceAircleaner cleaning systems are used for the general cleaning of workpiece contours and indentations (for example simple intermediate cleaning or pre-cleaning before final washers), our PrecisionAircleaner cleaning systems target defined cleaning tasks, which must ensure process reliability for subsequent work steps WITHOUT further work steps.

In both cases, the installed cleaning units in the “blow-off boxes” consist of nozzle assemblies directly adapted to the workpiece. This means there is no mere creation of wind and superficial blow-drying of the workpiece. The nozzles are individually aimed at areas to be cleaned, based on a patented process, to maximally utilise the flow of the compressed air. The movements of these nozzle assemblies are planned dependent on the environmental parameters (cycle time, size, process), and implemented in the system exactly defined.

More than 200 different types of nozzles are available to us for this cleaning process – however, this portfolio continues to be further developed and complemented by new products within the scope of energy efficiency: Rotary nozzles with various bearing, drive and retrieval systems are – if permitted by the workpiece contour – also used.

Our “blow-off boxes” (SurfaceAircleaner and PrecisionAircleaner) replace industrial parts washers for intermediate wash processes in many production lines. Process reliability after previous parts cleaning with our systems can even be guaranteed for example for subsequent screw connection or press-in operations.

Furthermore, no flushing cycle is required! This means connection to a washing water source or treatment station can be abandoned in most cases! As a consequence, there will be no unnecessary costs associated with treatment and/or disposal of the medium.

All systems are individually adapted to the workpiece types of our customers by taking energy efficiency into consideration, to be able to get most of the energy of the compressed air to the workpieces. Furthermore, all cleaning units are divided into several groups, to be able to clean every part of the workpiece individually with the actually required cleaning time and pressures (0.5-2 bar). It goes without saying that these properties, combined with energy-saving cleaning nozzles, create maximum effectiveness. Moreover, all our Aircleaner models are designed for operation with 3 bar networks.

Depending on the given cycle time, our Aircleaner cleaning systems have a connection value of for example 12 kW (comparison: crankcase, coolant, cycle time 60 seconds, cleaning time 40 seconds). Proportionally controlled, in this example this results in a consumption of approx. 9 kWh. This means as little as 0.15 kWh per workpiece.

If there is not sufficient space, of course our SurfaceAircleaner and PrecisionAircleaner cleaning systems can also be supplied via the compressed air networks of our customer. More information on this can be found under “Energy savings package”.

The SurfaceAircleaner and PrecisionAircleaner cleaning systems provide the following benefits:

  • Cleaning of complex structures
  • Cleaning of areas that are hard to reach (e.g. water spaces in cylinder heads)
  • Up to 98% removal of contaminations without additional workpiece flushing units (weight proportions)
  • No workpiece heating
  • No mixing of media
  • No compressed air consumption outside of cleaning cycles
  • External movement units
  • Simplest maintenance
  • Nozzles for process-relevant workpiece areas are fixed for quick replacement in case of damage
  • Nozzles for general areas are secured against maladjustments with patented ball joints
  • Automatic processing chamber cleaning
  • Design as inline concept, as gantry-loaded system or as special designs with several loading and unloading options
  • Precise workpiece preparation for subsequent processes

KNOTH offers the following additional options:

  • Stand-alone control unit, incl. CPU and display
  • Energy efficiency package
  • Stand-alone supply via compressed air station
  • Return pumping station
  • Stand-alone extraction units
  • Different separating devices

Typical workpieces / applications for precision cleaning with compressed air:

Automotive (truck / passenger car)

  • Motor: Crankcase, cylinder head, crankshaft, camshaft, connecting rod, balance shaft, turbocharger, pump housing, valve housing etc.  
  • Gear unit: Clutch housing, gear case, countershaft, drive shaft, gear shaft, gear wheels, shifting fork, shift lever, CV transmission shafts etc.
  • Steering: Steering rack, steering gearbox etc.
  • Drive: Drive shaft, calliper, cardan shaft, quick-release axle, thrust tube etc.
  • Chassis: Steering knuckles, half-axis, U-joint crosses, wheel carriers, servo pump, pin fork, track rod end etc.
  • Body: Chassis parts, special section tubes, air conditioning compressor elements etc.
  • E-mobility (electric motor): Rotor shaft, stator, motor housing, battery compartments, electrical connecting elements

Machining tools / measuring equipment

  • Cleaning of measuring equipment
  • Injection tools
  • Extruder tools
  • Workpiece holders
  • Workpiece clamping adapter

White goods / household goods

  • Aluminium housing, pump elements, compressor elements, compression elements etc.

Non-metallic workpieces

  • Plastic, ceramic, glass fibre, carbon etc.

Large-scale production parts & precision parts

  • Hydraulic components, valve blocks etc.
  • Screws etc.


  • Packaging