WIWA: WIWA spray technology

WIWA 250 D Airless spray gun with easy-moving two-finger trigger, spray technology

AIR COMBI automatic gun, spray technology

AIR COMBI manual spray gun, spray technology

WIWA 400 Airless automatic gun, spray technology

WIWA 300 automatic gun, spray technology

WIWA 500 F and return flow manifold for hot spraying systems. Robust Airless spray technology spray gun with four-finger trigger and front connection

WIWA 500 D Airless high-performance spray gun with WIWA swivel and easy-moving four-finger trigger, spray technology

Compressed air spray processes

With this conventional spray process/spray technology, the material to be processed is atomized at a very high air pressure of about 2 to 8 bar. The spraying equipment, painting systems and coating systems are relatively simple and cheap and the necessary air is generated by a compressor.

Advantages of this spray technology:

Very fine atomization enhances surface quality
Can be set on a very precise and flexible basis to match the object to be coated.
Very suitable for small and very small amounts
Runny materials can be processed very well due to the material application amount that you can precisely regulate on the spray gun
Cheap and simple spraying system

Disadvantages of the spray technology

The fine atomization achieves a high overspray
Only about 30% of the material is actually applied to the workpiece.
Low application performance
Only suitable for materials with a low solid content
Highly viscose materials can only be processed to a limited extent

Airless spray technology, Airless spraying equipment

Airless spray technology is an economical and environmentally friendly spray process with a high application performance. The high pressure pump draws the spraying agent from any desired container and transfers it to the spray gun under high hydraulic pressure via a high pressure hose. With Airless spray technology, fine, airless atomisation is achieved through a specially designed spray nozzle. The spray jet is ejected onto the material at high speed, thereby providing an optimal finish.

Advantages of this spray technology:

High working speeds
Good spraying due to superfine paint droplets
Easy handling of the spray gun
Paint can be taken from the original containers
High material yield

Disadvantages of this spray technology:

Relatively large amount of time and effort for cleaning
Complex apparatus
High rate of nozzle wear
During spraying, it is not possible to regulate the application amount
In the case of spraying errors, there is clouding and striping
Increased investment necessary

Air Combi spray technology combines the advantages of Airless and conventional spray processes. Using this painting method, the spraying agent is transferred to the spray gun under moderate pressure and pre-atomised. The fine spray distribution is achieved by applying regulated compressed air as the paint is discharged. A soft, controllable spray jet is produced with minimum paint mist. Ideal for highly refined painting tasks on large surface areas as well as for angular components and shaped or small workpieces.

Advantages of this spray technology:

Less overspray, fine atomization
High application performance
The application amount can be regulated by changing the spraying pressure
The width of the spray jet can be regulated by means of the support air
Highly suitable for materials with a high solid content
It is also possible to process highly viscose materials, which means that thick layers are possible in just one pass

Disadvantages of this spray technology:

Coarser atomization than with conventional air sprays
Only suitable to a limited extent for coating small parts
A lot of material is needed to fill the pump and hose

HVLP spray technology

HVLP stands for "High Volume, Low Pressure". With this spray technology, the spraying agent is atomized at low air pressure of about 0.2 to 1 bar and at high air volumes. A compressor or a turbine make available the necessary amount of air.

Advantages:

Less overspray
Apart from the electrostatic systems, the system with the highest material application rate (up to 80 %)
Low energy consumption
Lower disposal costs
Ideal with small-surface processing and repairs
Suitable for difficult spraying conditions in body corners or spaces
Runny materials can be processed very well due to the material application amount that you can precisely regulate

Disadvantages:

Coarser atomization than with conventional air sprays
Highly viscose materials must be thinned more
As with high-pressure spraying, the viscosity of the paint must be matched to the spray gun
Slower processing speed

Electrostatic spray technology

In the case of electrostatic spraying, the paint is electrically charged – generally in the spray gun. These charged paint particles go along electrical field lines from the spray gun to the workpiece. Due to the electrostatic wrap-around effect, it is often not necessary to rotate the parts with this spray technology; this is particularly the case with filigree or pipe-like objects. Even surfaces where it is not possible to achieve a wrap-around effect are suitable for electrostatic spray technology, since there is virtually no overspray.

Advantages:

Material saving of around 25-30 %
Shorter application times, since difficult areas are easy to reach and the wrap-around already paints the rear to some extent.
Better painting quality – completely even layer thickness, perfect
coverage of edges.
Protected environment for the paint operative: Overspray can be avoided.
Less maintenance: Because the spray booth is less contaminated.
Environmental protection: Because less solvents are released.

Disadvantages:

Can only be implemented with workpieces that are electrically conductive
Due to the electrical charge, you must take particular fire prevention measures