Sandblasting vs wetblasting is the question that comes up anytime a blasting job is needed. These are two surface treatment processes that use abrasive media to clean, prepare, or shape surfaces. Sandblasting is a more traditional process that uses dry abrasive media, while wetblasting uses a mixture of abrasive media and water.
Both sandblasting and wetblasting are effective processes, but they have different advantages and disadvantages. Sandblasting is typically faster and less expensive, but it creates more dust and can be more aggressive on surfaces. Wetblasting is slower and more expensive, but it creates less dust and is gentler on surfaces.
In this comparison paper, we will discuss the advantages and disadvantages of sandblasting and wetblasting in more detail and provide guidance on how to choose the best process for a particular job.
What is sandblasting?
Sandblasting, also known as abrasive blasting, is a process that uses a stream of abrasive material to clean, smooth, roughen, or shape a surface. The abrasive material is typically propelled by compressed air, at a very high pressure.
Sandblasting is a powerful tool, but it can also be dangerous if it is not used properly. It is important to wear proper personal protective equipment (PPE) when sandblasting, including safety glasses, a respirator, and gloves. It is also important to use sandblasting equipment in a well-ventilated area.
Key features of sandblasting
Media: Common blasting media include sand, aluminum oxide, glass beads, walnut shells, and silicon carbide. The hardness and shape provide different cutting effects.
Nozzle: The blasting nozzle focuses the incoming compressed air and media stream into a directed jet. Nozzle sizes, materials, and shapes vary.
Compressor: Provides high pressure (60-150 psi) compressed air to accelerate the abrasive media and direct it against the work surface.
Blasting gun: Handheld trigger gun with controls to start and stop the air/media flow. Allows aiming the blast at the workpiece.
Surface profile: Sandblasting erodes the top layer of the substrate, leaving a rough, textured profile for coatings to adhere to.
Dust containment: Sandblasting generates large amounts of potentially toxic fine dust requiring containment and personal protection.
Media recovery: Spent media and residue must be captured, cleaned, and recycled via cyclone separators and screening rigs.
Applications for sandblasting
Sandblasting is used in a wide variety of applications, including:
- Cleaning surfaces to remove rust, paint, graffiti, and other contaminants
- Preparing surfaces for painting, coating, or welding
- Roughening surfaces to improve adhesion
- Shaping surfaces, such as removing excess material or creating a textured finish
Advantages and disadvantages of sandblasting
It is very important that you can consider all what sandblasting implies, so you can take the best decision when choosing the process to go. So, here are some of the advantages and disadvantages of sandblasting.
Advantages of sandblasting
Effective cleaning and preparation: This is a very effective way to clean and prepare surfaces for painting, coating, or welding. It can remove rust, paint, graffiti, and other contaminants quickly and easily.
Versatile: Can be used on a wide variety of materials, including metal, wood, concrete, metal, stone, fiberglass, and brick.
Inexpensive: This is a relatively inexpensive method of surface cleaning and preparation.
Uniform results: Produces consistent surface profile and cleaning action across large surface areas.
Accessibility: Complex or confined geometries can be blasted using specialty nozzles and machines.
Automatable: Can be adapted to automated blasting systems and robots for continuous processing.
Relatively easy to use: Sandblasting equipment is relatively easy to use, even for beginners.
Disadvantages of sandblasting
Dangerous: It can be dangerous if not used properly. Sandblasting can create a lot of dust and debris, which can be harmful to breathing. Sandblasting can also damage delicate surfaces. It is important to wear proper personal protective equipment (PPE) when sandblasting, including safety glasses, a respirator, and gloves.
Creates dust and debris: It can create a lot of dust and debris, which can be harmful to breathe and can also damage surfaces in the surrounding area. It is important to take steps to control dust and debris when sandblasting, such as using a dust collection system and working in a well-ventilated area.
Can damage delicate surfaces: Sandblasting is a powerful tool that can damage delicate surfaces, such as glass, ceramics, and plastics. It is important to carefully select the abrasive material and blasting pressure when sandblasting delicate surfaces.
Line of sight process: Limitations blasting recessed or concealed areas without special tooling.
Operator skill: Producing a consistent surface profile requires an experienced blaster technique.
Air compressor demand: Requires large volumes of high pressure compressed air.
Noise: Blasting operations generate noise levels exceeding 85dB, necessitating hearing protection.
Cleanup: Spent media and dust must be thoroughly cleaned from equipment and work area after blasting.
What is wet blasting?
Wetblasting, also known as hydroblasting, vaporblasting, liquid honing, and slurry blasting, is a process that uses a mixture of abrasive media and water to clean, smooth, roughen, or shape a surface. The mixture is propelled by compressed air and applied to the surface through a nozzle.
It is safe to say that wetblasting combines the abrasive cutting action of traditional dry sandblasting with the benefits of water for suppression, cleaning, and containment.
Key features of wetblasting
Dust suppression: The water captures dust generated during blasting, minimizing airborne particles. This reduces clean up and hazards.
Reduced media rebound: Water causes the abrasive to lose energy upon impact, reducing bounce-back and making the process more efficient.
Cooling: Water cools the surface during blasting which can enable more aggressive material removal on heat sensitive materials.
Rust/paint stripping: Water enhances the paint and corrosion removal effects of the abrasive.
Cleaning: Water flushes away blasting residue, leaving a clean surface without secondary cleaning required.
Containment: Closed loop wetblasting systems contain all water, media, and waste for recycling or disposal.
Media options: Wetblasting can utilize traditional abrasives as well as soluble media, sponge particles, ice, and others.
Environmental advantages: The containment of blast debris prevents hazardous dust and footing hazards.
Applications for wetblasting
Wetblasting is used in a wide variety of applications, including:
- Cleaning surfaces to remove rust, paint, graffiti, and other contaminants
- Preparing surfaces for painting, coating, or welding
- Roughening surfaces to improve adhesion
- Shaping surfaces, such as removing excess material or creating a textured finish
Advantages and disadvantages of wet blasting
Wetblasting is a versatile and effective tool that can be used for a variety of purposes. It is a good alternative to sandblasting, especially for jobs that require a high degree of precision or where dust control is important. Anyway, it is convenient to consider at length its advantages and disadvantages.
Advantages of wetblasting
Reduced dust: It creates much less dust than sandblasting, making it a safer and more environmentally friendly process.
Gentler on surfaces: It is less aggressive than sandblasting, making it ideal for cleaning delicate surfaces.
Improved finish: Wet blasting can produce a smoother and more consistent finish than sandblasting.
Can be used on a wide variety of materials: Wet blasting can be used safely on metal, wood, concrete, brick, and other materials.
Visibility: Operators can see the surface condition better through the water vapor.
Reduced media rebound: Water inhibits abrasive from bouncing back off the surface, improving efficiency.
Waste containment: Water and abrasive/coating debris can be collected for disposal rather than contaminating soil.
No static electricity: Water eliminates static sparking hazards when blasting sensitive explosives or flammable coatings.
Relatively inexpensive and easy to use: Wet blasting equipment is relatively inexpensive and easy to use.
Disadvantages of wetblasting
Can be slower than sandblasting: Can be slower than sandblasting, especially on tough jobs.
Added equipment: Requires water pumps, capture tanks, treatment systems and splash guards.
Part drying time: Surfaces require thorough drying after blasting before coating.
Shorter media life: Water forces abrasives into target more rapidly, slowing their breakdown but requiring more frequent replacement.
Corrosion promotion: Without thorough drying, retained water can initiate surface corrosion and coating defects.
Process complications: Adding water requires monitoring flow rates, abrasive saturation, nozzle wear, and other parameters.
Can create a mess: Wet blasting can create a mess, so it is important to take steps to protect the work area.
Sandblasting vs wetblasting: Comparison
When comparing sandblasting vs wetblasting, there are tradeoffs to consider in choosing the best method:
Choose sandblasting for:
Lower setup costs: Requires less ancillary equipment like water pumps, tanks, and reclamation systems.
Faster process times: No drying step required between blasting and coating application.
No moisture risks: Eliminates any risks of flash rusting or coating defects from retained moisture.
Simpler process: Does not require monitoring water quality, flow rates, nozzle clogging, etc.
Familiar technology: Traditional dry sandblasting methods are better known by most operators.
Choose wetblasting for:
Superior dust control: Greatly reduces risks from airborne contaminants and contains waste.
Lower media consumption: Water prevents abrasive from being ejected from the surface, requiring less media.
Cooling benefits: Allows more aggressive blasting on delicate or heat-sensitive materials.
Enhanced cleaning: Water improves removal of coatings, mill scale, and rust.
Reusable media: Water keeps abrasive cleaner and allows recycling it more times.
Operator comfort: Water vapor is more comfortable to work in than clouds of dust.
Environmental: Containment reduces pollution, hazards, and clean up.
Sandblasting vs wetblasting in a nutshell
After reading separately about these 2 processes, here are some additional considerations when choosing between wet blasting and sandblasting, regarding the same point:
Cost: Wet blasting is typically more expensive than sandblasting, but the difference in cost may be offset by the reduced need for dust control measures.
Environmental impact: Wet blasting is more environmentally friendly than sandblasting, as it produces less dust and waterborne pollutants.
Surface type: Wet blasting is a good choice for delicate surfaces, while sandblasting is better suited for tough surfaces.
Desired finish: Wet blasting can produce a smoother and more consistent finish than sandblasting.
Job requirements: If the job requires a high degree of precision or where dust control is important, then wet blasting is the better choice.
Sandblasting vs wet blasting: Final thoughts
The best process for a particular job will depend on a number of factors, including the type of surface being treated, the desired finish, and the budget.
In general, sandblasting is a good choice for jobs where speed and cost are important, while wetblasting is a good choice for jobs where dust control and surface integrity are important.
We have several decades of helping companies to define the appropriate abrasive blasting for their circumstances. Feel free to reach out to us so we can help you too with the equipment and assessment you need to get started.
