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Paint spray guns

The paint gun is the fundamental tool of the painter, what would your car's finish if they had been painted with a brush?, Thanks to the evolution of paint guns, now get excellent aesthetic finishes with a high speed application and with a lower consumption of paints and solvents.

The spray guns are the family of paint guns more common in the car repair area, are the most widespread and used guns, thanks to the ease of handling and excellent aesthetic paint finishes obtained.

The spray guns base their operation on spraying paint into small particles by the physical phenomenon known as the venturi effect.

Imagine you have a full glass of water to which place a tube, if we blew the tube horizontally we can see that the water rises due to depression, until impact with the air blow, spraying the water into fine particles; this phenomenon is the venturi effect.

To make the spray or paint atomization, spray guns have the following 2 inputs:

The input of air is the means by which air flows at a pressure of between 3 and 6 bar for conventional spray guns, this air will impact on the paint at the exit of the gun in order to break it into small particles, this process is known as atomization or spray of the paint.

The input of paint is the means by which the paint is supplied to the gun, in this type of pistols feeding the paint can be by:

The suction and gravity spray guns, are appropriate when we have to paint small areas or to carry out paints retouches, cup volume determines the amount of paint that can be applied.

Within the range of spray guns we find 3 families of different guns depending on the technology used:

The spray guns HVLP (High Volume Low Pressure) and use less pressure and more air volume to atomize the paint, getting lessen the impact velocity of the particles of paint on the workpiece, thus reducing the rebound of paint and the high overspray and mist created with the conventional spray guns, so that by using the HVLP reduces the consumption of paint thus decreasing the consumption of solvents and emission of VOC's (volatile organic compounds), which is why this type of gun also known as green guns.

The hybrid spray guns were developed due the need of the market for the use of HVLP technology in applications with more viscous paints, where it is necessary higher level of atomization of the paint in order to obtain excellent finishes, this is achieved by increasing outlet pressure of 0.7 bar air available to the HVLP to 1.5 bar available to the hybrid, while maintaining the same volume or flow of air than HVLP.

Below is a table comparing the advantages and disadvantages of conventional spray guns.

Conventional spray gun advantages:
Conventional spray gun disadvantages:
    • Economic guns, low investment costs

    • Easy to use

    • Easy adjustment of range width and amount of paint

    • Uniform layer thickness

    • Quality finish

    • Easy to clean

    • Low maintenance

    • Low flow

    • Only for apply low viscosity products

    • Low efficiency of paint transfer

    • High overspray

    • For gravity and suction guns can be applied only a small amount of paint

paint spray gun

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