Electrostatic turbo bell is the best choice for high quality paint spraying. Either for paint thickness control or surface evenness, turbo bell is unbeatable choice comparing to any other spray gun model. How does an electrostatic turbo bell work and how it’s outstanding from the industry? In this article we’ll briefly introduce from it’s turbo structure design to final application and see why it’s primary choice for high end application.
Electrostatic Turbo Bell Brief View
Being a high end choice spray gun tool, electrostatic turbo bell provides a special design for paint atomizing (up to 60,000 rpm bell rotation speed). The atomized paint is unlike traditional liquid flow but fog like tiny particles as a result of the high speed spinning. Thus paint atomizing grade is extremely high comparing to any other spraying technologies.
How does electrostatic turbo bell work? When spraying with an electrostatic turbo bell, the object is grounded as the anode, turbo bell is connected to a negative high voltage as the cathode, bell is driven by an air turbine. When the paint is sent to the high-speed spinning bell, the paint stretches into a thin film on the bell inner surface due to the centrifugal effect of spinning. Paint obtains huge acceleration to move to edge of the bell then broken into tiny fog like particles under the action of centrifugal force and strong electric field. It is a very fine charged fog that moves to the object surface with opposite polarity to form a uniform coating film.
Electrostatic Turbo bell Advantages
- Paint consumption significantly reduced
- Equipment costs reduced due to the simplified paint booth
- Coating environments improved
- Paint losses and cleaning costs reduced
- Fine atomization due to high-speed rotation and fine finish achieved
- High Transfer Efficiency
- The rotation speed, shaping air pressure and delivery can be freely changed by remote control operations to achieve the best value easily for various coating conditions.
- Applicable to a wide range of workpieces
- Supported materials expended
- 2-component coating material mixed inside the bell
The work logic of a turbo bell (From Graco Probell)
Three fluid lines are connected to the ProBell: the fluid supply, the solvent supply, and the dump line. There are also nine airline connections for various functions, such as triggering valves, bearing air and shaping air.
A low-voltage cable supplies low voltage to the power supply. A magnetic pickup monitors the speed or rotational speed of the turbine.
The air bearing supply should be set between 70 and 100 psi. It should be on all the time to keep the bearing in a floating condition.
The turbine is a match-fit to the air bearing, so there’s a dimensional tolerance that will require a clean, dry air supply.
The bearing air has a return line that provides a pneumatic signal back to the controller pressure switch, so the controller has verification that the air supply to the air bearing is active and ready for operation.
The inner shaping airflow captures and propels the paint towards a part being painted.
The outer shaping airflow assists in bringing the pattern together to help define the pattern shape and improve the transfer efficiency.
Dual shaping air provides a higher degree of pattern control, pattern adjustability, and makes it easier to paint into small spaces and corners.
Turbine air is used to drive the turbine at a rotational speed, ranging from 10,000 to 60,000 rpm (revolutions per minute). A valve-to-piston (V-to-P) ratio is used to adjust this airflow to the turbine to maintain the program speed.
Brake air is used to reduce the speed of the turbine for fast speed changes. The magnetic pick up sensor monitors the rotation of the turbine, providing feedback to the controller by fiber optics.
