Wholesale/Supplier Wet and Dry Sandblasting Equipment Automatic Sandblasting Machine

What is a Sandblast Cabinet?

Sandblast cabinets include systems or machinery and components for projecting blast media against a part's surface to abrade, clean, or modify the surface. Sand, abrasive, metal shot, and other blast media are driven or propelled using pressurized water, compressed air, or a blast wheel.

Sandblast cabinets are also known as abrasive blast cabinets, dry blast cabinets, wet blasting cabinets, micro-abrasive blast cabinets, micro-blasters, micro-jet machines, and shot peening cabinets.

Sandblast Cabinet Technology

If you want an answer to, "How do sandblasters work?", then you will need a better understanding of the technology empowering blast equipment. The shape and hardness properties of the media, or whether any media is used at all, is another parameter controlling the blasting process.

The technology employed to energize, propel or project the blast media is an important aspect characterizing sandblast cabinet types.

The propulsion technologies blast machinery employs to clean, peen, or modify surfaces include:

Air Blast or Dry Blast Cabinets - Air abrasive blasting or dry blast equipment utilized compressed air to move the blast media. Pneumatic or compressed air blast systems can be divided into two types, suction, and direct pressure.

Suction or Siphon Blast Cabinet - Suction blasters or blast cabinets employ the venturi siphon effect to such abrasive into a pressurized stream of fluid, air, or water.

Direct Pressure or Pressure Blast Cabinets - Pressure or direct pressure abrasive blast equipment makes use of a pressure vessel to energize the abrasive media. A pop-up or metering valve on the pressure vessel is opened to release pressurized fluid and blast media into a blast hose. The pressurized media travels through the blast hose to the direct pressure cabinet and blast gun.

Direct pressure cabinet blast machines expel the blast media at much higher flow rates or speeds compared to suction blast equipment. Impact or kinetic energy (K) of the blast media is K = ½ mv² where m = blast media mass and v = velocity.

Doubling the flow or velocity quadruples the impact energy and blast cleaning efficiency.

The higher blast media speeds enable direct pressure systems to impact clean parts up to 4 times faster than suction blast machines. Pressure levels are more adjustable with direct pressure blast cabinets, so cleaning and surface modification can be more precisely controlled.

Direct pressure blast equipment can lift and propel heavy media such as steel shot, cut wire shot, and steel grit. Suction sandblasters struggle with heavy media. Doubling the blast media mass doubles the impact energy. Heavier blast media (denser or larger) is more efficient at cleaning and profiling compared to lighter, lower density, or smaller media.

The higher speeds, ability to handle heavy steel media, more aggressive nature and better control of direct pressure sandblast cabinet make pressure blast equipment more widely employed in high volume production and automated blasting applications. The higher blast media speeds enable pressure sandblaster guns to operate at greater stand-off distances from the part.

Wet Abrasive Blast Cabinets - Water can replace air as the fluid used to propel the blast media. Wet abrasive blast or water blasting can reduce the dust generated during abrasive blasting by over 90%, which can be important when stripping or cleaning a part containing heavy metals and hazardous materials. While some suppliers refer to wet abrasive blasters as dustless blast equipment, no abrasive blasting system suppresses 100% of the dust generated.

Water blasting can keep the parts cooler compared to dry blasting, which can reduce warping or distortion of thin sections. If the dust generated during blasting is explosive such as aluminum or titanium dust, then wet blasting is advantageous because static discharges and ignition are suppressed.

Water blasting can consume up to 50% less blast media compared to dry blasting. Wet blasting provides deep cleaning with less or no imbedding of abrasive media. Wet blasting systems can employ closed-loop media can recyclers, oil separators, demisters, and filtration systems. Dust is converted to clean, disposable sludge waste.

In dry blasting, the dust must be removed with an air blow gun or washing. Wet blasting combined washing and dedusting with the blasting step. Detergents can be added to the water to loosen deposits, dissolve oils or greases and accelerate the cleaning process.
Rust inhibiting agents can be added to the water to prevent rusting of wet steel after the blasting process is complete. If rust suppressors are not added to the water, then the steel should be dried, oiled, or painted after blasting to prevent rust formation.
Bacteria and microbes can grow in the blast water forming slime films and releasing odors. The blast water like other metalworking fluids and grinding coolants require the addition of antimicrobial agents.