PAINT & POWDER efficiency . To the contrary , low pressure air spray guns are streamlined and performance capabilities have limitations .
Rotary bell applicators are designed exclusively for automation . They offer some unique functionalities not possible with air guns , such as automatic spray head rinsing and integrated fluid return dump valves . Some can include internal fluid valves for internal 2K mixing of plural components inside the atomizer or for internal color changing . With automatic spray head cleaning , they can be more sustainable for continuous operation allowing for reduced manual cleaning and maintenance .
Another difference is that air spray guns rely on cleanliness of the air cap orifices and overall condition to ensure a repeatable and consistent painting result . Sometimes a bad air cap can create unwanted splits and paint slug type defects . Rotary bells commonly produce a more repeatable finishing process .
Typically , paint coatings used in the general industry are formulated for use by manual hand held air atomizers . Automatic versions of the same applicator are used for automated processes . To use the same coatings with rotary bells , viscosity or reducing solvent changes might need to be adjusted to produce optimal or improved painting results .
Type of applicator has a big influence to robot path programming . Air guns require that manipulators manage wrist positioning very specifically to keep the oval shaped paint spray patterns orientated specifically on the work piece . In contrast , the symmetrical plume produced by rotary bells allow robots more freedom of movement , enables shorter cycle times and greatly simplifies robot motion programs and paths , which helps avoid singularity issues . Based on the applicator overall size , weight , and angle as mounted on the robot can make programming easy or difficult . Overall , air guns tend to be smaller and lighter weight .
Experience from the auto industry has proven rotary bells can offer considerable advantages based on paint savings , reduced cycle time , maintainability , paint re-work , and booth cleaning . In circumstances when paints have very high cost or the quality standards require a smooth appearance , rotary bells might be the better choice . Clearcoat finishes are more appealing when applied by rotary bells due an increase of evaporated solvents , which enhances material flow properties and helps prevent unwanted solvent pop defects . Depending on your paint process and targets for your automatic spray process , air guns can be the best overall choice .
In summary , both types of applicators have specific pros and cons . Air guns , particularly HVLP type applicators , are considered benchmark atomizers for low pressure painting in the general industry . Rotary bell atomizers can offer significant key improvements for robotic painting . In the end , both atomizer technologies should be openly and carefully considered for your specific robotic spray process .
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