Industrial Sandblast Rooms – A complete Planning Guide
Industrial blasting facilities can provide tremendous benefits to your manufacturing operation. A blast room can allow you to improve your facilities blast production and save on blast media costs. A blast room can also be costly so it is important to understand all the factors to consider when evaluating a blast room to determine what makes sense for your blasting needs.
Factor 1 – Pre Built or Self Made
Pre Built Blast rooms offer a variety of benefits. First, they are specifically engineered to handle the demands of abrasive blasting. Abrasive blasting creates a lot of dust and places demands on the structure it is done in. Pre designed blast rooms from a quality manufacturer like Clemco will have a variety of features to help reduce problems with dust and the structural demands. A pre designed room will have a variety of design features that are incorporated to keep blast media migrating outside of the blast room to a minimum. This can be beneficial when you are blasting product near a paint area and you want to be able to keep your product free from abrasive dust. Additionally, a pre designed blast room will incorporate design features that are meant to prevent excessive blast media from coming into contact with your dust collector which can result in a longer life for your dust collector. Final design features will typically include rigid walls with reinforcement as well as liners that will prevent your underlying walls from deteriorating due to blast media. The underlying structure will also be built of 10 Gauge steel which is very thick and will withstand the demands of blasting well. An additional benefit is that the blast room will have all of its components tied together to allow for ideal operation. The main downside to a completely pre-built blast facility is that they can be costly.
Self-made facilities will typically allow for a lower cost project, but they can often be difficult to build in a way that will last as long as a pre designed facility. It will be harder as well to keep your blast media as well contained which can be important if you need a clean shop environment or will be concerned with blast media migrating toward an area close to your blast facility. If you want to build your own facility you will want to build the walls with heavy gauge steel if possible as well as implement design features to help reduce blast media from migrating outside of the blast area. You will also want to line the walls with an appropriate liner to prevent the underlying structure from wearing out prematurely, we often recommended reclaimed coal mining belt hung loosely from the wall which will allow you to protect the walls at a low cost.
Factor 2 – The Media Recovery Equipment
The type of media recovery equipment you implement will depend on the type of blast media you use in your blast facility. Three main types of media recovery equipment exist and each is designed to accommodate certain types of media (see below for an overview).
Steel Grit, Steel Shot – These types of blast media will typically utilize a mechanical blast media recovery system, which uses a bucket elevator to bring media up to a cyclonic separator that will remove any unwanted contaminant from the media and allow clean media to be placed back into the blast media hopper.
Plastic, Aluminum oxide, and glass bead media – if you are using lightweight media like plastic or glass which is meant mostly to remove coating without harming the substrate like plastic or glass blast media you will typically want to consider a pneumatic media recovery system. A pneumatic media recovery system uses the flow of air is being pulled by your dust collector to move the media into the cyclonic separator that will allow the media to be cleaned and placed back into the blast pot.
In addition to the style of media recovery equipment that you select, you’ll also want to consider how much floor space you want to use when recovering media. Media recovery can be as small as a 3 x 3 hopper in the corner of the room or as large as the entire floor of the blast facility. The larger area you have available to recover blast media, the higher production levels you’ll be able to sustain. However, recovery areas will also require additional equipment which will add to the overall cost of your blast facility. You can also opt for choices that are between a full room and hopper like a single conveyor down the middle of the room or an H pattern in the floor, these options will allow you to sweep media a shorter distance and can help speed up media recovery time.
You also want to consider the type of recovery system that you want to use if you are using more than a 3 x 3 hopper. Common options for media recovery from the floor include pneumatic systems, belt driven systems,screw driven driven systems, and flat trak systems. For the most part if you using a heavy body media a belt driven system will typically provide the longest life without issues and function effectively. For lighter weight medias pneumatic systems are the common choice. Other options like the flat Trak and screw driven system can sometimes make sense depending on the application.
Factor 3-Dust collection for the blast environment
Since sandblasting creates an excessive volume of dust, you want to consider how you will properly vacate the blast facility of dust. You also want to make sure that whatever option you choose will meet all national standards like those enforced by OSHA. The air velocity your blast room will require will depend on what you are blasting off the surface of the product (certain hazardous materials like aerospace paints may require different air velocities). One thing to know is that dust collectors designed for general use are not the same as dust collectors that are built to accommodate blast environments. A general dust collector may cost an initially less money, but they will typically not last as long and there will also be additional costs that can add up. In particular general use dust collectors will often need to have their filters replaced at a higher frequency than a comparable collector that is built for the blast environment. Dust collector filters can easily cost thousands of dollars to replace. Additionally, a collector built for the blast environment will incorporate protective shields to prevent blast media from damaging the internals of your dust collector. If you will be incorporating a blast media recovery system you will need to oversize the dust collector so that it will be able to collect dust from your cyclonic separator which will typically require an additional 500 – 1200 CFM of capacity.
Factor 4 – The Size of the Blast Room
You will want to size your blast room to be able to properly maneuver products as well as allow the blast operator to blast. It is a good idea to allow at least 5 additional feet of space around each side of the product which will provide the operator room to properly work. In choosing the design of the room you typically want to keep the face opening size down to the minimum size you can, this is because the size of your dust collector is typically calculated based on the air flow across the front opening size of the blast room.
Factor 5 – Product Size and Product Flow Through the Blast Room
Blast rooms can be designed to accommodate drive through configurations or where product is brought in and out the same way. The drive through configurations will often allow for higher production levels as you can move your product through an assembly process with minimal unloading and loading time (this can be helpful for higher production volume needs) but the drive through design will typically be more expensive. You will also want to consider how the product will be maneuvered into and out of the blast area. If you will be doing relatively low batches you can often utilize an option like a fork lift or similar option. However, if you will be moving product routinely or if the product is heavy you may want to consider an option like an overhead crane and a crane slot in the blast room to allow the product to be loaded with ease.
Factor 6- Support
We’ve implemented a variety of blast rooms for customers in our area over time and have often had to deal with a variety of issues that have happened in the blast room. Issues including problems with their blast pots functioning correctly to media recovery equipment being worn out from use over time. When these issues occur, if you cannot get timely assistance getting your equipment back up and running you can lose significant time to your production process. That is why is usually ideal to consider whether or not you will have support and parts for your equipment in stock when issues arise.
A blast media recovery room is a large investment with a lot of options to consider. You will ideally want to evaluate the level of production you will want to achieve, the type of media you will use, the size of your product (and if movement will be a problem), and the quality of equipment you may use. By evaluating these factors, you will be better able to determine a blast media set up that will meet your needs effectively.
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