There are many key factors that must come together to be able to use electrostatic guns effectively. First you should select the proper atomization technology for the 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 used in applications that require a “Class A” automotive finish. The guns offer lots of control at the gun such as for example fluid flow by utilization of the fluid needle adjustment knob and fan control through the utilization of the fan adjustment knob. Furthermore, the total amount of fluid can be controlled by how far back the operator pulls the trigger. This really is referred to as “feathering” the gun.
The key source of fluid control is decided by the fluid pressure from the low-pressure pump, the air starting a pressure pot or with a fluid regulator mounted near, or in the spray booth. The viscosity of the coating and how big is the fluid nozzle also affect the fluid flow. Although air spray electrostatic guns have great atomization, they are also the least efficient of the electrostatic guns. This really is as a result of the potential utilization of high air pressure to atomize the coating. The use 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 is the HVLP electrostatic gun. The gun operates almost identically to the air spray gun except so it uses less atomizing air pressure. Instead, spray on protection the gun uses more cubic feet of compressed air or CFM. The effect is a gentler spray pattern which lowers the velocity at that your paint particles travel. This permits for more of the charged particles to remain in the electrostatic field which supports to improve transfer efficiency. Like any HVLP gun, some coatings might be too viscous or the application form rate might be too high, which may make it burdensome for the HVLP electrostatic gun to supply high productivity and acceptable finish quality for a few applications. Furthermore, HVLP guns usually require more CFM that may cause 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 will be the principal way of atomizing the coatings. Once the gun is triggered, the high fluid pressure is allowed to flee into the atmosphere through a tungsten carbide tip that’s cut to make an elliptical spray pattern. The size of 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.
In general, airless technology does not provide the exact same amount of atomization as air spray or HVLP electrostatic guns but they work nicely for a few coatings, particularly when spraying large products at high rates of speed. Tip plugging is definitely an issue when spraying materials that contain an aggregate such as for example 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 expected to generate the fluid pressure. Since these kind of guns use lower fluid pressure than airless and less air pressure than air spray, they are able to 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 more effective than either the air spray or the airless electrostatic guns. Sometimes they are even more effective compared to HVLP electrostatic guns.
However, air-assisted airless electrostatic guns don’t offer the exact same amount of control at the gun since the air spray or HVLP electrostatic guns. This is because the fluid pattern cannot be fully adjusted from very narrow to very wide without changing the tip. Also, such as the airless electrostatic gun, the operator cannot feather the gun. This might be problematic when spraying very complex substrates where in actuality the operator needs that type of control at the gun. Tip plugging can be a concern with some aggregate filled materials.
The most efficient manual electrostatic spray gun is really a portable 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 effect is very good transfer efficiency. However, the gun creates a doughnut-shaped spray pattern which does not work nicely for some production finishing applications and is employed mostly for the on-site refinishing industry.