EST. 1971

Abrasive Blast Rooms

RSI and Airblast AFC has developed a powerful reputation throughout the world for our reliable, durable and sophisticated surface preparation and coating solutions which make our customers more efficient, productive and profitable. This brochure gives a short outline of the blast booths, abrasive recovery, recycling, and ventilation products offered by RSI and Airblast AFC.

RSI and Air blast AFC equipment sets industry standards and as a result our products are being used with great success in many markets, ranging from multi-million dollar full aircraft stripping hangars, to booths for preparing rolling stock, to an array of smaller industrial enclosures.

Introductory

Beginning at the blast machine the pressure and abrasive content is set to the required limits. Once the operator has closed the dead-mans handle, abrasive is propelled under pressure through a high quality 12 bar blast hose of 1.25” bore and in-turn the blast nozzle. This is only possible provided all safety
interlocks are closed on doors, etc

At this point the abrasive and substrate coating break down into four constituents; i.e. good abrasive, spent abrasive, large contaminants and dust. Good abrasive, spent abrasive and any large contaminants fall to the
recovery floor. Airborne dust particles are carried on the flow of air through the room generated by the dust collector.

The constituents now in the floor are conveyed to the elevator and in turn the Dynamic Separator. This unit comprises of a primary vibrator sieve and air wash. In this section any remaining dust is taken to the dust collector, spent abrasive and large contaminants to a collection bin. This method of separating spent abrasive, in a way that they are not taken to the dust collector, means that the collector elements are prevented from suffering premature wear. The operator, by adjusting the power of the vacuum placed
on the abrasive, decides what minimum size of particle he wishes to remain in the system; i.e. the higher the vacuum the larger the particle taken out of the abrasive.

Introductory
Beginning at the blast machine the pressure and abrasive content is set to the required limits. Once the operator has closed the dead-mans handle, abrasive is propelled under pressure through a high quality 12 bar blast hose of 1.25” bore and in-turn the blast nozzle. This is only possible provided all safety
interlocks are closed on doors, etc.

Clean abrasive is now all that remains and is deposited in a silo equal in capacity to the volume of the blast machine or machines. Once all the abrasive in the blast machine has been delivered (or at any other time the operator releases the dead-mans handle), the blast machine is automatically charged with fresh abrasive from the silo above.

RSI / Airblast AFC Blast Rooms with Full Recovery Floor

In this energy saving option two longitudinal corridors are driven by a bell crank driven by the transversal corridor at the end of the blast room. Our flexible “no mechanical” blades glide over foreign objects dropped into the floor mechanism, which usually stall a metal scraper. Also, as we have no mechanical hinge, the danger of dust causing the hinge to seize is eliminated.
Several corridors run the length of the facility deploying abrasive into a transversal corridor running at right angles to the longitudinal corridors. In this case a pit, with recovery floor, is facilitated by dropping the transversal below it by 130mm.

The RSI – Airblast AFC Recovery Floor automatically recovers abrasive material from beneath the operators’ feet. A full recovery floor effectively renders the blaster with an endless supply of media, thus eliminating the need to stop production to recover media. The Airflex floor is made of modular corridors of various standard widths that can be produced to any length. Six widths are available, and with this flexibility it is possible to recover from virtually any floor area.

Each corridor has a series of flexible rubber blades set at regular intervals. The blades rest against galvanized steel combs thus allowing it to push or pull the abrasive when the comb is behind the rubber. On the alternate stroke the comb passes through the abrasive and the rubber blade passes over it. This back and forth motion, when repeated, causes the abrasive to be shunted along with each alternate stroke.

Eventually, each individual accumulation of abrasive, in the linear corridors, is deposited into a transversal corridor running at right angles to the rest of the floor. This transversal corridor transfers the abrasive to the elevator and grit wash prior to being deposited into the silo over the blasting vessel.

Benefits

 Little or no civil works. With a step of only 5.125” it is possible to put the system on your existing floor level.
 Virtually silent working operation.

 Flexible scraper blades provide for long life compared to other fixed steel blade systems. Scraper blades provide much less long- term maintenance issues as compared to a screw-type auger system.

 No moving metal components in operation in the abrasive circuit or hinges, which are prone to grit ingress. One stalled or stuck scraper blade renders the recovery floor area behind it unable to recover media.

 No compressed air consumption. Typically we drive our floor sections with a 1.5kW motor. Other systems incorporate pneumatic drives which can be prone to wear in a dusty environment.

 Bucket Elevator and grit wash provide three filter / cleaning devices. This design results in efficient separation of constituents (good abrasive, spent abrasive, large contaminants and dust) and longer life expectancy of cartridge filters.

 A standard feature of all our dust extractors is our bin balance system. This system offers protection to the operator when disposing of the dust collected in the machine. By linking the outside of a bag, placed in the collection bin, to the dirty side of the dust collector we can prevent the bag from being pulled into the hopper of the extractor. This allows the operator to seal the bag and its contents before disposal. Systems that do not employ this method often leave the operator engulfed in dust, which he is supposed to be protected from, when emptying the contents of the collection bin.

Booth Construction

Our modular style booth enclosure is based on a 10′ x 3′ galvanized tray interspaced with structural steel to provide rigidity. This concept has proved to be a popular industry-wide choice and by producing in volume, we are able to keep our production costs low and offer much faster lead times than our competitors.
Booths based on this design meet the majority of our customers’ requirements but if a custom enclosure is required for a particular project we will design and manufacture made-to-measure panels. Connecting these panels by a diaphragm plate means that the structure will maintain its intended integrity (shown here in blue).

One of our unique features is the ease at which our booths can be installed as a waterproof option. Rather than relying on the flat roof, container-type booth offered by many of our competitors, we prefer to incorporate our modular booth into a portal framed cold rolled steel building. Booths based on mass produced shipping containers have their place in the market as a budgetary solution as they can be converted into a reasonable enclosure for blasting. However, their flat roof and single skin construction inevitably lead to a number of problems ranging from a short working life to ongoing condensation within the work area.
We utilize sophisticated design software, which when used in conjunction with the Zip/Postal Code for the area where the blast room is to be located, allows us to design a cold rolled galvanized portal steel structure that replaces the standard diaphragm system discussed earlier. The software also recognizes national and local building codes. By installing standard blast room panels to the inside of the structure and cladding to the exterior, a cost effective weatherproof blast bay is produced.

Lighting

Doors

Sound Attenuation

Dust and impact resistant high intensity lights.

RSI and Airblast AFC has perfected the ability to replace fluorescent blast room lights with high intensity 400W metal halide units. Ignored by our industry because of the problems associated with extreme heat and the percussive effect of abrasive on the light glass resulting in the glass shattering. These light units are a standard feature on most of our facilities. With the correctly sourced glass diffuser we are able to withstand the rigors of the blast booth environment.

By utilizing these units the lux achieved is
superior to other products. Each unit is
positioned outside the booth shining light
through the glass which sits on a seal
fitted to an aperture in the roof. This
ensures that there is no build up of dust
which can be found when light systems
are fitted to the booth itself.

Designed for value, quality and performance.

Our cargo doors stand testament to our
belief in organic design. Many blast room
doors fail as a result of their structural
weakness – large doors hanging off
proprietary hinges in a blast booth often
leading to problems. Our design capabilities and non-reliance on outsourced components mean that we always provide a superior door hinge of such strength that enables us to hang doors up to 20′ high x 20′ wide.

Our design ensures that our doors will be
used over many years without the need for rubber curtains which can be trapped in the door or its hinges.

Sound attenuation for improved working
conditions outside of the booth and
limiting environmental impact.

All of our blast booth panels and doors are designed to accept sound attenuating
foam. In the case of an external booth, the
cavity between the blast booth and the
external building also provides an ideal
space for compressed rock wool.

Media Recovery Floor

This scraper floor has many features that separate it from those offered by our competitors.

The most specified product in our range. This scraper floor has many features that separate it from those offered by our competitors. The scrapers comprise of a natural rubber flap set against a steel comb, multiples of which are set in 10′ long frames. This assembly is then adjoined to others to form a corridor running the length of the blast booth.

Available in six standard widths, each corridor moves in a reciprocating back and forth motion. Because the distance between the scrapers is less than the distance of travel, each scraper moves abrasive forward, as the rubber flap in this direction is locked against the steel comb behind it, to the next (A) in a shunting motion. On the reverse stroke the rubber scraper blade, unhindered in this direction by the steel comb, is free to pass over the
previous scrappers deposit of abrasive (B). The abrasive is pushed forward to a final corridor positioned at right angles to the booth where it conveys the abrasive to an elevator and is recycled.

The depth of the recovery channel is only 5″ ensuring that in many instances, ie. those where objects being taken into the booth may be carried by hand, it can be located directly onto an existing factory floor. When a flush finish is required between the factory floor and the blast room, only minor excavation is required. The scraper system
is covered by a pedestrian grating (C) on which the operator stands and through which the abrasive falls. In certain applications when heavy items are being processed, this grating can be increased in strength to provide greater loading capacities. An alternative method of supporting a heavier item is to incorporate rails into the floor, positioned conveniently between the recovery corridors on which a cart can be mounted.

Abrasive Elevators

Our method of grit reclassification is proven to extend the life of dust extraction filter cartridges.

With a recovery floor the RSI Airblast AFC elevator requires no pit. Designed to allow abrasive to be picked up as it is pushed into its base from the recovery floor, the abrasive passes up through a vibrating sieve which discharges oversized contaminants to a collection bin at floor level. Smaller particles of abrasive then pass through a dynamic air wash where dust is discharged into the dust collector.

Undersized abrasive is also eliminated. Rather than being conveyed with the dust to the dust
extractor, in our system undersized abrasive is also delivered to the collection bin at floor level. When undersized abrasive is taken to the dust collector, its mass causes it to travel faster than the maximum filter velocity dictated by the filter manufacturer. This results in premature wear to the filter media.

Our method of grit cleaning is proven to significantly extend the life of filter cartridges or bags. This is very important as changing the dust extraction filters is the single most costly maintenance issue associated with any blast booth.

Large Capacity Elevator & Abrasive Recycle

In those instances where an abrasive recovery floor is not required or cannot be justified, we offer two “sweep to” systems. The most advanced of these systems is an adaptation of our elevator which allows for a much larger capacity for storing abrasive. This system can provide for up to 8 hours continuous blasting.

Vaculift

A cheaper and simpler grit elevator and recycler is the RSI Airblast AFC Vaculift. Rather than physically vacuuming the abrasive the Vaculift system blows the abrasive vertically. As fast as the abrasive can be swept to the Vaculift hopper it is delivered by a micro venturi at its base, through a ceramic and steel pipe into a ventilated air plenum where dust is extracted to the dust collection unit.

Non-Recovery Floor – Steel Floor Detail

Where a recovery floor is not installed in a large booth RSI Airblast AFC will incorporat e a detail into the ¼” steel plate floor. This provides a guide rail against which a plow can be run pushed by a fork lift or skid loader. This durable feature allows for rapid recovery of abrasive to the elevator.

Abrasive Elevators

Providing market leading standards of visibility with the blast booth for optimum safety and production.

Our booths provide market leading standards for operator visibility and dust extraction. Very often the environment within our booth differs very little in terms of visibility from that of the environment in which you are probably reading this brochure.

Our dust extraction units are not only calculated to provide booth airflow of 50ft per minute but our carefully designed replacement air inlets and outlets ensure that there is no turbulence within the booth maintaining optimum conditions.

Plastic Media Stripping

Plastic Media Blasting (PMB) is a dry abrasive blasting process, designed to replace chemical paint stripping operations and conventional sand blasting. This process uses soft, angular plastic particles as the blasting medium. The process blasts the plastic media at a much lower pressure (less than 40 psi) than conventional blasting. PMB is well suited for stripping paints on substrates that could be damaged, since the low pressure and relatively soft plastic medium have minimal effect on the surfaces beneath the paint.

After blasting, the media is passed through a sophisticated reclamation system that consists of cyclone centrifuges, air wash, multiple vibrating classifier screen decks, and a magnetic separator. In addition, some instances call for dense particle separators as part of the reclamation system. The denser particles, such as paint chips, are separated from the reusable blast media, and the reusable media is returned to the blast machine.

Below is one of the turnkey projects incorporating PMB that RSI Airblast AFC has built for the Royal Air force.

Containerized Booths

When an item to be blasted can be processed within the constraints of a standard shipping container a containerized booth may be considered. This versatile mass manufactured watertight box is an ideal starting point for a blast room particularly when the booth may be relocated at some point or if it is to be situated outside in the elements.

RSI Airblast AFC purchases new containers and re-design them to incorporate features
described earlier on this site. Options range from booths simply ventilated with media reclaimed by use of a Vaculift to the incorporation of full recovery floors.

Rhodes Systems International