High pressure paint spraying

FIGURE 1.6 Airless or high pressure paint spraying. (From Wang, L.K. et al. Case Studies of Cleaner Production and Site Remediation, Training Manual DTT-5-4-95, United Nations Industrial Development Organization, Industrial Sectors and Environment Division, Vienna, Austria, April 1995.)... 

Fan Spray 100-1000 High-pressure painting/coat ing, Annular combustors Good atomization, Narrow elliptical spray pattern High supply pressure... 

Galvanized Painted Ceiling and Walls High pressure water spraying 80 - 99+... 

Painted Steel Walls, Ceiling, High pressure water spraying 70 - 95... 

In conventional spraying paint is forced under pressure to the spray gun, where it mixes with air and, forced through a small orifice, atomises. Airless spray is created by forcing paint at extremely high pressures through an accurately designed small hole. Rapid expansion as it leaves the gun produces an extremely fine and very even spray pattern. No air is mixed with the paint before it leaves the gun, so avoiding dry spray . A wetter, heavier... 

Airless spray In this process, a high pressure (12-35 MN/m ) is applied to the paint to force it through a fine orifice in the spray gun. This process allows rapid transfer with reduced overspray. 

Airless Spraying the process of atomisation of paint by forcing it through an orifice at high pressure. This effect is often aided by the vaporisation of the solvents especially if the paint has been previously heated. The term is not generally applied to those electrostatic spraying processes which do not use air for atomisation. 

A method for atomizing and spraying a liquid, suspension, or emulsion by high pressure, without using compressed gas at the spray nozzle. Also termed hydraulic spraying . Airless spraying is used for paints and urethanes among others. 

The most widely used method of application in heavy industrial projects is airless spraying. This utilises high pressure, the liquid paint being ejected through a fine specially designed nozzle which causes the paint stream to break up into fine droplets in the form of a fan. This rapid method of paint deposition also allows application of high dry-film thickness with each coat, 150 /an being not unusual in this respect. A coat of "decorative paint applied by brush would probably yield a thickness of 30-40 fim. 

As part of the NAFTA Technical Working Group on Pesticides, priority areas for development of biocide applicator data have been agreed upon. These include, in order of priority, high-pressure spray, low-pressure spray, painting (roller/brush), wipe/mop, place solids, aerosol spray, painting (airless), pour solid, pour liquid and pump liquid. 

Sodium bicarbonate is also used in cleaning products on both a household and industrial level. Many householders use commercial baking soda, such as that sold by the Arm Hammer company, to clean kitchen and bathroom appliances, such as sinks, stoves, and toilet bowls. Industries also use sodium bicarbonate filters to remove sulfur dioxide and other pollutants in flu gases released from factory smokestacks. The compound is also used in the treatment of wastewater to maintain proper acidity, remove certain odors (such as those of sulfur dioxide), and destroy bacteria. Some communities have used aqueous solutions of sodium bicarbonate sprayed at high pressure to remove graffiti paint soot and smoke residues and mold from buildings, walls, and other public structures. 

Surface-Painted metal surface. Polymeric Application Method-High pressure spray (700-1400 psi) Manufacture-Dry Blend/Agglomerati on Composition Wt%... 

D. Injection of hydrocarbons can cause local tissue inflammation, pain, and necrosis. Severe scarring and loss of function has occurred after injection into a finger with a paint gun or other high-pressure spray device containing a hydrocarbon solvent. Often the puncture wound and local swelling appear minor, but tracking of hydrocarbon solvent down fascial planes into the palm may cause widespread inflammation and injury. 

High-pressure injection injuries (eg, from paint spray guns) are important not because of systemic toxicity due to absorption of an injected substance (eg, paint thinner) but because of extensive irritant-related tissue necrosis. Emergency surgical evaluation of such cases is mandatory. 

In airless hydraulic) atomization the paint is forced through a slit nozzle of hard metal under high pressure (8-40 MPa). On account of the high degree of turbulence, the paint stream disintegrates immediately after leaving the fluid tip. A similar atomization process occurs in spray cans where the paint pressure is produced by the propellant gas. 

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