Blast Room 101: Things You Should Know About Blast Booth

Like blast cabinets, blast rooms are large enclosures for operators to perform abrasive blasting without any dust emission into the atmosphere. We can think of them as a vast blast cabinet, but the operators are working inside the enclosure instead of outside it.
Let’s go over a typical blast room layout of the blast chamber.

The blast chamber and enclosure used to house abrasive blasting operations can vary extensively inside based upon application requirements. Most blast rooms are customized and sized according to application requirements for more minor blast room requirements.
There are many ways to modify a shipping container for the blast chamber.

We have a partial blast chamber layout for the modified shipping container. The blasting chamber only uses. A partial section of the shipping container and the dust collector uses the rest of the shipping container. The whole shipping container provides ventilation to the blast chamber, and the abrasive recycling and cleaning system is housed outside the shipping container. However, its feed hopper is located within the blast chamber. It allows the blast operator to manually shovel the spent abrasive after blasting it into the feed hopper for further recycling and reuse.
We also have a modified shipping container whose entire container is a blast chamber with an abrasive reclamation and ventilation system sitting outside at the rear of the shipping container.

Because we are building a customized product to suit a particular application, all aspects of the project must be considered to come up with the best design that meets the customers’ requirements and budget constraints and within the physical limitations of the installation site(if any).

Key considerations and Information required for the project would include:

• Maximum dimensions of the weight of the workpiece
• Production, the volume needed for the various workpieces
• Number of blast operators and production shifts
• An abrasive media type that will use
• Physical size and limitations of the installation site, if any
• Availability of existing work handling equipment
• Availability and scope of compressed air supply
• Availability and type of electrical supply
• Integration of blast room system with other new or existing factory equipment (for example, paint room)
• Customers project budget

There are many ways to the blast chamber structure. So long as liners protect the internal surfaces of the blast booth from the abrasive blast stream and the structural integrity is adequate to meet customer expectations. It does not matter what construction method is used.

There are multiple door options for blast chambers. Some common ones include sliding swings and roller shutter doors. Image one shows a sliding door-style blast chamber where the doors open sideways, similar to a building elevator. Image two shows a dual swing door-style blast chamber where the doors open outwards. Finally, image number three offers a roller-shutter-door type design. On the left side of the image, we can see the blast chamber outside with the door in the rolled-up position.

Work handling systems can range from sophisticated mechanized trolleys and turntables with articulated work platforms to basic manual fixed platform track and trolley handling, depending on the client’s requirements and project budget.

• Image number one is a typical full-blown work handling solution with articulated work platforms for the operators to traverse the blast chamber’s length, height, and width. Tracks are located in the center of the blasting chamber for the workpieces to get in or out.
• Image two shows an alternate blast room layout to suit inline production operations by having two sets of doors on each end of the blast chamber. The multiple trolleys can minimize abrasive blasting downtime. The extra trolley containing the unblasted workpiece can immediately be moved into the blasting chamber for immediate blasting after the blasted workpiece on the other trolley is moved out from the opposite end of the blast chamber.
• Finally, image number three is also a hoist-crane workpiece handling solution, in which workpieces can be up & down during blast processing to blast processing the bottom.

• The blast chamber must have an excellent ventilation system for an operator to have adequate visibility during blasting. The blast chamber should be equipped with a dust collector at the opposite end of the inlet air plenum to provide the required air crossflow to remove airborne dust and fine abrasive media.
• To get the best performance of the dust collecting system, we need to calculate the cross-sectional area of the blast chamber in square feet and then multiply the flow factor by 30 for metallic abrasive or 45 for nonmetallic abrasive. Then we will get the required dust collector flow rate in CFM. And add 10% to the required flow rate if more than one blast operator uses the blast room system.
• Due to dust overloading from the high abrasive breakdown rates, The blast room system can never use the single-use expendable abrasive media, such as copper slag, crushed glass, or silica sand,
• BlastKing standard dust collector sizes include 3000 CFM, 4500 CFM, 5000 CFM, 5500 CFM, 7500 CFM, 9000 CFM, 10000 CFM, 12000 CFM, 15000 CFM, 20000 CFM, and 30000 CFM. If an application is between standard sizes, it’s better to upsize to the next available size for improved operator visibility.

Like blast chambers, ventilation can also customize dust collectors to suit applications that cannot use standard dust collector designs. For example, let’s take the size of a 5m×5m×10m blast room, a sample that will operate with glass beads (nonmetallic abrasives). The cross-sectional area will be 5m×5m equaling 25 square meters or 269 square feet. Multiplying this by 45 gives us 12109 CFM so that we can select the standard 12000 CFM unit as the ventilation dust collector for this chamber size.

Broadly speaking, there are three ways for abrasive media to be recovered for recycling and reuse:

• Manual recovery
• Mechanical recovery
• Pneumatic recovery

With a pit-mounted recovery system. Must take extra care to ensure that the pit stays dry with no possibility of water entry or adequate drainage provisions to drainage provisions to keep the hole dry. Any water ingress into the abrasive reclamation system will cause equipment failure and loss of production time.

Most mechanical recovery systems are extensions of the manual abrasive reclamation system, provide a means to reduce the effort of operators sweeping required, and mechanically convey the spent abrasive media into the feed hopper or directly into the boot of the bucket elevator.