EnviroSpec’s Technical Library
Section: Description – Specialty Rotating Nozzles
These rotating pressure water nozzles have a zero degree nozzle assembly that is contained in a housing. The water pressure is used to spin this nozzle assembly around the inside of the housing. The tip of the nozzle assembly rotates in a very tight pattern against a race in the front of the body. The back section rotates inside a larger section of the body. The result is a zero degree nozzle that rapidly spins in a cone shape. This produces a much larger contact area with the surface to be worked than would be contacted without the rotating action. Rotating pressure washer nozzles are used when strong impact won’t damage the surface. They are ideal for paint preparation, stone cleaning, etc. The nozzle needs to be sized properly to the equipment. If the orifice is too large it won’t spin quickly and the impact will be less. An undersized rotating nozzle will spin very fast and hit hard, but it probably will fail prematurely.
Section: Surface Damage
Be aware of what the nozzle is doing. The more powerful the tool, the closer you need to watch. Rotating pressure specialty washer nozzles have a strong impact. If, for example you are paint prepping a house, the wood siding can easily be splintered and gouged. Some sidings are softer than others. So watching carefully and adjusting the distance between the nozzle and the surface is the only way to accomplish the job without causing damage.
EnviroSpec’s Technical Library
Section: Specialty Rotating Nozzle Sizes
By size meaning the whole nozzle, not the orifice size. The larger the diameter of the nozzle housing the wider the cone spray angle will be. The wider the cone angle, the larger the surface contact and the faster you will be able to work. The larger the nozzle body the more the nozzle weighs. This becomes a comfort factor sometimes when working for long periods. By using a lance with a 45-degree bend at the end instead of a straight lance the nozzle, the weight can be offset by the water thrust. A large nozzle housing can also make it difficult to work in tight places.
Section: Usage Tips
Keep the nozzle pointed down when starting to spray. The nozzle tip and race are constructed of ceramic. The ceramic can be damaged the impact caused by the water pressure. The parts are already in contact when the nozzle is pointing down. Any debris that gets into the rotary nozzle can potentially damage it. A single grain of sand can etch the ceramic race and cause the nozzle to stop spinning. That is why it is important to install a high-pressure filter just before the nozzle. This filter will block dirt that enters the water stream after the inlet water filter. There are many places for more debris to enter. Scale can break loose from the coil. Rust can be dislodged from fittings. Anytime you quick connect hoses together or connect a trigger gun, grit can get inside the lines. Test surface tolerance and effectiveness prior to doing a whole job. In rare cases a problem isn’t evident until the surface has dried. For example, sometimes when cleaning concrete if the rotary specialty nozzle is moved too rapidly it will leave circles on the surface. These circles don’t always show when the job is still wet. So if you do a complete job, say like a sidewalk in front of a store, you may end up getting a shock as the surface dries. The circles can be avoided by modifying your washing technique. Angling the nozzle spray to the surface, backing off, or slowing down can correct a problem like this. But without a test, you’ll never know.