There are numerous key factors that must come together to be able to use electrostatic guns effectively. First you must select the best atomization technology for your coating application needs. There are numerous electrostatic atomization technologies to choose from. The oldest and probably most typical will be the air spray electrostatic guns. These guns use compressed air as their primary and sole method of atomizing the coating. These guns are most commonly used in applications that require a “Class A” automotive finish. The guns offer lots of control at the gun such as for instance fluid flow by use of the fluid needle adjustment knob and fan control through the usage of the fan adjustment knob. Furthermore, the total amount of fluid could be controlled by how far back the operator pulls the trigger. This is referred to as “feathering” the gun.
The key source of fluid control is set by the fluid pressure from the low-pressure pump, the air entering a stress pot or by a fluid regulator mounted near, or in the spray booth. The viscosity of the coating and the size of the fluid nozzle also affect the fluid flow. Although air spray electrostatic guns have great atomization, they’re also the least efficient of the electrostatic guns. polyurea coating This is due to the potential use of high air pressure to atomize the coating. The utilization 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.
A variation of the air spray electrostatic gun could be the HVLP electrostatic gun. The gun operates almost identically to the air spray gun except so it uses less atomizing air pressure. Instead, the gun uses more cubic feet of compressed air or CFM. The result is a gentler spray pattern which lowers the velocity at which the paint particles travel. This enables for more of the charged particles to remain in the electrostatic field which supports to boost transfer efficiency. Like any HVLP gun, some coatings might be too viscous or the application form rate might be too high, which can ensure it is difficult for the HVLP electrostatic gun to provide high productivity and acceptable finish quality for a few applications. Furthermore, HVLP guns usually require more CFM that may lead to increased electrical costs for compressed air.
For the application form of very viscous materials and for very good application rates, some manufacturers use airless electrostatic guns. These guns use pumps to generate very good fluid pressure which is the primary method of atomizing the coatings. Once the gun is triggered, the high fluid pressure is allowed to escape to the atmosphere via a tungsten carbide tip that’s cut to make an elliptical spray pattern. How big is the pattern and the total 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 form rate.
Generally speaking, airless technology doesn’t provide the exact same degree of atomization as air spray or HVLP electrostatic guns however they work nicely for a few coatings, especially when spraying large products at high rates of speed. Tip plugging can be an issue when spraying materials which 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 needed to generate the fluid pressure. Since these kind of guns use lower fluid pressure than airless and less air pressure than air spray, they can offer companies a good compromise involving the speed of an airless and a finish quality closer to the air spray electrostatic. The best part is that technology is generally better than either the air spray or the airless electrostatic guns. In some cases they’re even better compared to the HVLP electrostatic guns.
However, air assisted airless electrostatic guns do not offer the exact same degree of control at the gun whilst the air spray or HVLP electrostatic guns. The reason being the fluid pattern can not 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 the operator needs that kind of control at the gun. Tip plugging can be a problem with some aggregate filled materials.
The most efficient manual electrostatic spray gun is really a handheld rotary atomizer. These guns use centrifugal forces and a very good voltage electrostatic field to atomize the material. While there is no atomizing air the paint particles travel very slowly through the electrostatic field. The result is very good transfer efficiency. However, the gun generates a doughnut shaped spray pattern which doesn’t work nicely for most production finishing applications and is employed mostly for the on-site refinishing industry.