Airless Paint Sprayers and Guns

An airless paint sprayer is a special type of paint spraying gun used to apply paint without the use of compressed air. Read more about it here.
Airless Paint Sprayers and Guns
Airless paint sprayers force paint through a paint spray gun, thus atomizing the paint, which then comes out through a small aperture at a high pressure, similar to a garden hose attached with a spray gun. Instead of a compressor, the pressure applied on the liquid comes from a piston pump unit or a motor driven diaphragm. They are called airless paint sprayers because compressed air is not used in order to provide the pressure required.

The size of the valve’s opening and the horsepower are the two numbers you need to check out when you want to determine the capabilities of a paint spray gun. Bigger sized pumps with larger valves are able to handle heavier paint coatings.

A wide range of finishes and coatings can be applied by airless paint sprayers in less time compared to other methods of applying paint. Plus, these paint sprayers can be used to apply the coating of paint at whatever thickness that you want.

Airless Paint Sprayers not used for Detailed Work

Airless paint sprayers are usually not used for spray painting jobs that require detailed work, such as cars or cabinets. They cannot be used for such applications because these paint spray guns apply too much paint too fast. These paint sprayers are ideal for exterior and interior surfaces such as buildings or fences. Airless paint sprayers are available in various designs and configurations; however, all of them generally have the same controls and features. It requires a lot of pressure to force a heavy fluid like paint through the small hole at the tip. Plus, there has to be adequate pressure in order to maintain a proper pattern of spraying that comes out of the tip.

There are Two Types of Airless Paint Sprayer Pumps

The airless paint sprayer’s basic components are: a pump; the hose; the gun; and the tip. There are two types of pumps – the piston and the diaphragm – and both of them work very well. Although the diaphragm type cannot pump very thick paint, which the piston type can handle very well. Hence, the piston pump type of airless paint sprayers are the more versatile.

The Piston Pump Type of Airless Paint Sprayer: This type comprises of several components which include a piston, check valves and packing. When the piston moves up it creates a vacuum so that the paint is sucked up inside a chamber, known as the fluid section, and then when the piston comes down it pushes the paint into a high pressure hose.

A seal is created by the packing so that there is no loss of pressure during the spray painting work. The airless paint sprayers used by professionals are equipped with packing that is self adjusting, which prevents premature wearing and the requirement for repairs.

The flow of the paint from the pump’s fluid section to the hose is directed by the check valves, or the ball and seat valves. This helps in preventing the paint being pumped backward through the pick-up tube.

The Diaphragm Pump Type of Airless Paint Sprayer: A piston is also used in the diaphragm type of airless paint sprayer, although in a different manner. Hydraulic fluid is moved by the piston in order to move the diaphragm, which results in paint being sucked up and then it being pushed through the hose and then the gun.

The diaphragm is not touched by any moving parts. The piston’s and the hydraulic fluid’s movement result in the diaphragm moving up and down in a very rapid manner. Although no packing is used in this design, however check valves have to be used.

This method of application requires a high-pressure hose, which is rated according to the pump’s maximum output of pressure. Typically, the operating pressure is 3000 psi. This hose is very tough, which has the ability to withstand considerably high amounts of pressure and is kink resistant. It is advisable never to try and repair this hose as it can result in an injury. Instead of repairing it is better to replace it.

The Airless Paint Spray Gun

The airless paint sprayer is controlled and the tip is held with the help of the spray gun. It looks like a handgun because it has a trigger and a handle. As soon as the trigger is pulled, the valve opens, which allows the paint to flow through the tip on to the surface that is being painted.

When choosing a spray gun, it is important to look for the comfort factor. Spray guns are either 2 or 4 finger guns. These numbers indicate the number of fingers required to pull the trigger.

The choice of the spray tip is dependent on the pump’s capabilities as well as the type of paint being sprayed. The choice of the spray tip will have an effect on the effectiveness and performance of the airless paint sprayer.

These are the main components that all airless paint sprayers comprise of. Your requirements and expectations will determine the type you choose to buy. Keep in mind that the thicker the paint, the more power you will require.

By Rita Putatunda
Published: 12/11/2007
 
Use the feedback form below to submit your comments.
Your Comments:
Your Name:
Use the form below to email this article to your friends.
Recipient Email Address:
 Separate multiple email addresses by ;
Your Name:
Your Email Address: