There are many key factors that must get together to be able to use electrostatic guns effectively. First you have to select the proper atomization technology for your coating application needs. There are many electrostatic atomization technologies to choose from. The oldest and probably most common will be the air spray electrostatic guns. These guns use compressed air as their primary and sole way of atomizing the coating. These guns are most commonly utilized in applications that want a “Class A” automotive finish. The guns offer lots of control at the gun such as for instance fluid flow by utilization of the fluid needle adjustment knob and fan control through the use of the fan adjustment knob. In addition, the amount of fluid could be controlled by how far back the operator pulls the trigger. This really is called “feathering” the gun.
The key supply of fluid control is set by the fluid pressure from the low-pressure pump, the air entering a force pot or by a fluid regulator mounted near, or in the spray booth. The viscosity of the coating and how big the fluid nozzle also affect the fluid flow. Although air spray electrostatic guns have great atomization, they’re also minimal efficient of the electrostatic guns. This really is because of the potential utilization of high air pressure to atomize the coating. The usage of high air pressure can defeat the electrostatic attraction by forcing the charged particles of paint after dark part or by creating excessive bounce back or overspray.
An alternative of the air spray electrostatic gun could be the HVLP electrostatic gun. spray on coating The gun operates almost identically to the air spray gun except that it uses less atomizing air pressure. Instead, the gun uses more cubic feet of compressed air or CFM. The end result is a softer spray pattern that lowers the velocity at that the paint particles travel. This enables for more of the charged particles to stay in the electrostatic field which helps to boost transfer efficiency. Like any HVLP gun, some coatings might be too viscous or the application rate might be too high, that might ensure it is hard for the HVLP electrostatic gun to provide high productivity and acceptable finish quality for a few applications. In addition, HVLP guns usually require more CFM that may result in increased electrical costs for compressed air.
For the application of very viscous materials or for very high application rates, some manufacturers use airless electrostatic guns. These guns use pumps to produce very high fluid pressure which can be the principal way of atomizing the coatings. Once the gun is triggered, the high fluid pressure is allowed to escape in to the atmosphere via a tungsten carbide tip that’s cut to create an elliptical spray pattern. The size of the pattern and the amount of fluid leaving the gun are controlled by the tip. The viscosity of the coating and the fluid pressure used also affects the application rate.
In general, airless technology does not provide the same degree of atomization as air spray or HVLP electrostatic guns but they work well for a few coatings, especially when spraying large products at high rates of speed. Tip plugging can be an issue when spraying materials that contain an aggregate such as for instance silica or zinc. Air-assisted airless electrostatic is really a hybrid version of the airless electrostatic and the air spray electrostatic. These guns use both fluid pressure and air pressure to atomize the coating. Pumps are essential to produce fluid pressure. Since this kind of guns use lower fluid pressure than airless and less air pressure than air spray, they could offer companies a great compromise between the speed of an airless and a finished quality nearer to the air spray electrostatic. The best part is that technology is normally better than either the air spray or the airless electrostatic guns. In some instances, they’re even better than the HVLP electrostatic guns.
However, air-assisted airless electrostatic guns don’t offer the same degree of control at the gun as the air spray or HVLP electrostatic guns. This is because the fluid pattern can’t be fully adjusted from very narrow to very wide without changing the tip. Also, like the airless electrostatic gun, the operator cannot feather the gun. This may be problematic when spraying very complex substrates where in fact the operator needs that type of control at the gun. Tip plugging may also be a concern with some aggregate filled materials.
Probably the most efficient manual electrostatic spray gun is really a handheld rotary atomizer. These guns use centrifugal forces and a very high voltage electrostatic field to atomize the material. Since there is no atomizing air the paint particles travel very slowly through the electrostatic field. The end result is very high transfer efficiency. However, the gun puts out a doughnut-shaped spray pattern which does not work well for some production finishing applications and is employed mostly for the on-site refinishing industry.