Rugged construction matters. Ask yourself if the unit is constructed to prevent damage to the unit in industrial use. What to look for:
Heavy-duty structural steel frame
Heavy wall / tubing thickness
Heavy-duty fork pockets and lifting eyes
Corrosion-proof coating and corrosion resistant components
The inner workings of the equipment a) determine if it is a true vapor blast machine and b) indicate likely impediments to smooth operation of your investment over time. (You don’t want to invest in a future “boat anchor” or “doorstop”.)
Low pressure vs. (red flag) high pressure
The beauty and essence of true vapor blasting relies on non-damaging low pressure. Any system using high pressure is not vapor blasting, but a derivative of UHP wet jetting, and will not provide the safety benefits of true vapor blasting.
Dedicated vapor blast vs. (red flag) dry blasting option
True vapor blasting is moisture- driven process. If there is an option to blast using dry grit, it is a hybrid system, not vapor blasting.
Hydraulic pressure vs. (red flag) air pressure only
True vapor blast (the business end) is driven by hydraulic pressure, or pressurized water. Presence of halo nozzles or pressurized air at the hose or valve (business end of the machine), indicates it’s not a vapor blasting machine. If grit remains dry in the hopper/pot, and/or there’s no water pump, it’s not true vapor blasting.
Gravity fed vs. (red flag) induction fed
True vapor blasting relies on a gravity-fed grit/water mixture. Hydraulic pressure condenses the grit, creating essentially grit that is moistened by, and cushioned by water droplets in a “mist” type form, adding mass and force to grit impact while protecting surfaces from damage and mitigating ricochet and risk of grit or substrate particle dispersion into air. Slurry blasting relies on induction-fed grit/water mixtures and is prone to regular clogging, pressure drops and is suppresses dust roughly half as efficiently as true vapor blasting.
True vapor blast machines require grit to be placed into the hopper/pot, which is then filled with liquid (no water measuring needed) which self-pressurizes once the lid is closed/sealed. “Standing” water supply tanks in self-contained vapor blast equipment allows continual and consistent hydraulic pressure in the hopper/pot. If the hopper/pot must be manually filled with water, or grit is moistened at the blast hose (outside the hopper/pot), it is not true vapor blasting.
Is rinse mode “switch & go” immediate, or does it require hose/system flush to get rid of residual grit first?
Valve type: pinch valve vs. (red flag) Thompson valve
No-fail automatic pinch valve offer maximum durability with precise control and virtually no maintenance. A heavy-duty, rugged pinch mechanism positions the sleeve, resulting in precise control and accurate flow control. High-quality pinch valves have no packing to maintain or seats to wear and no fugitive emissions to worry about. Thompson valves in blasting systems are notorious for clogging and being susceptible to heavy wear (with associated breakdown). Better vapor blasting machines do not use Thompson valves.
(red flag) CFM loss/pressure drop/inconcise pressure range
Loss negates control. Engineered blast circuits for virtually no CFM loss work in tandem with variable user-set pressure control, variable water control, and automated no-fail water (fluid) pressure injection are all important features on state-of-the-art vapor blasting machines.
Comprehensive engineering vs. (red flag) makeshift jerry-rigging
Fewer “moving parts” generally means translates into less risk of, and less opportunities for breakdown, which translates into less maintenance, less guesswork when trouble shooting and less complicated repairs.
It almost goes without saying that simple, elegant solutions are preferred, as a maximum desired effect achieved with the smallest, or simplest effort leads to more productivity. CleanerBlast manufactured machines epitomize simple, elegant vapor blasting solutions, using knowledge gained from decades of in-house and trial and error tests in real-world conditions. CleanerBlast engineers understand and what each component is designed to do and how they work together, CleanerBlast machines are engineered for maximum performance using the lowest number of “moving parts”. Each component has a specific purpose. Each configuration has been closely examined to maximize operability, robust operation, efficiency and user-friendliness.
That makes a huge difference, as evidenced by what CleanerBlast technicians regularly find when they service, repair, reconfigure or retrofit customer’s existing units made by other manufacturers (that were previously “boat anchors”) to increase operability and productivity. In doing so, CleanerBlast has discovered with each generation of vapor blasting that many manufacturers seem to have mistakenly tweaked or jerry-rigged systems leading to unnecessary parts and convoluted configurations that detract from the overall functionality of the machine. Extraneous parts may indicate the maker/designer doesn't intricately understand the precise contribution of each component to the vapor blasting system's performance.
Size is a factor here. Lighter weight, self-contained and compact units will travel better, be easier to set up and fit in tight spaces.
Number of required hoses
Vapor blasting is a bit different from dry abrasive blasting when it comes to determining the number of hoses needed. If you plan to vapor blast and then immediately rinse down and treat surfaces, a machine with dual pumps and independent nozzles for blasting and rinsing simultaneously is a better fit. For open-air operations with plenty of space where projects require large areas of blast cleaning, you may want multiple blast nozzles. Conversely, multiple compact machines may perform the job better in large enclosed areas like tanks, where hose to operator proximity ensures better maneuverability.
Suitability to use environment
Humidity, large areas, enclosed spaces, proximity to sensors, environmental protection considerations
Any system requiring a large, truck size volume of water or manual hopper fill is not a true vapor blast system. Standing water supply tanks are an integral part of self-contained true vapor blast units, therefore the tank size will determine how frequently water must be replenished, affecting time “on the blast hose”. Rinse mode will also draw from the standing water supply tank. True vapor blasting equipment will shut off when water is depleted. The size of the water supply tank is an important factor in operations where difficult to access sites with little access to a water source are the norm.
Hopper or pot size
Storage of grit is generally not a problem, as true vapor blast machines consume up to 90% less media. However, as in any abrasive cleaning operation, hopper/pot capacity will determine frequency of grit reloading and affect time “on the blast hose”.
Self-contained vapor blast equipment runs on a charge from a separate air compressor. Run time or blast time will vary from unit to unit. Expect up to 2 hours between charges for very small units; up to 5 hours for larger units. If operations normally require blast cleaning large areas, a larger machine is a better fit.
Ease of access
Easy access to filters and components not only makes maintenance faster and easier but also can affect equipment service life. Removing parts simply to gain access for cleaning or replacing other regularly maintained components creates unnecessary and unwanted opportunities for improper reinstallation. In tight or enclosed space use, lack of easy access can be a huge impediment to smooth operations.
The question here is whether parts are easy to find, and standard across the industry, or if they must only be ordered from the manufacturer (factory parts). In remote locations, this can make the difference between a couple of hours of downtime and a week’s lost productivity.
Many vapor blast machines are able to use quite a wide range of media (from fine to very coarse) but it’s worth asking the manufacturer how efficient the machine is using any grit types and sizes you regularly use so you can compare efficiency for your operation. Most distributors will even provide demos so you can measure results in the field.
Compatibility with other surface preparation processes
The correct vapor blasting solution for your situation may require compatibility with alternative media (such as organics or soda), or chemical surface treatments. Most vapor blast equipment accepts liquid surface preparation treatments, but pot/hopper material or coating compatibility or vulnerability to the chemicals in the treatment or alternative media may vary by manufacturer. When in doubt, ask.