When we launched the Finishing Academy training resource website in January of 2011, we didn’t just want it to be a one-way stream of information. The Finishing Academy is an extensive resource covering a great deal of information on a variety of finishing topics, and it’s always going to be expanding to include more. We know that there’s no way we can cover every topic and answer every question that exists in every finishing shop in the world, but what we can do is provide a forum where you can get your specific questions answered by our team of experts. So, shortly after we created the Finishing Academy added a button link to the site where you can ‘Ask Us A Question!’. Regardless of what kind of equipment you have or what kind of business you run, you can get your questions answered by the GFS team.
Here are just a few of the questions we’ve received so far from the community, and we will continue to make these answers available to everyone here on the Booth Blog, and in future training information on the Finishing Academy website. Enjoy!
“How many types of paint booths are there?“
This is a tough question to answer, as they are many different “types” of paint booths in terms of airflow style, cabin design, ceiling and pit design, size and features. Booths can be completely enclosed or open in the front (i.e. “open-face”). There is also the main difference between liquid and powder coating booths. For liquid finishing, the two basic types are dry filter booths and water wash booths. For powder coating, there are different styles of powder collection booths.
Examples of a Downdraft (left) and Semi-Downdraft (right) spray booth
Several factors must be considered when determining the appropriate spray booth design for your application. The section on “Spray Booth Design” on the Finishing Academy goes into detail about these factors to explain what you should look for in a booth (http://finishingacademy.com/training/Refinish/Module1/mod1_sys_design.html).
The maximum temperature in the spray area of an enclosed spray booth is 200°F, per NFPA 33 – Standard for Spray Application Using Flammable or Combustible Materials, 2011 Edition. This temperature can be reached in most recirculating spray booths. Quite often there is no need to reach that temperature, since the spray area only needs to get hot enough to cure the paint. Contact the paint manufacturer to learn the optimal temperature for curing.
“How far does a baking booth have to be from the actual paint booth?“
It depends. NFPA 33 requires that booths shall be separated from other operations by a minimum distance of 3 feet or by a partition or wall having a minimum fire resistance rating of 1 hour. This allows access for cleaning and maintenance and minimizes the potential for the spread of fire. However, you may connect your spray booth directly to your oven so that the product can be moved directly from one to the other. If you do, interconnecting doors shall include an interlock to prevent spraying if the doors are open.
A high-temperature limit is required in the spray area to shut down the oven heating system if the temperature in the booth exceeds 200 F. If your process does not allow for interconnecting doors, then you need a pressurized vestibule between your booth and oven. The vestibule must separate the booth from the oven by at least 3 feet. Airflow into the vestibule must be proven so that a loss of airflow shuts down either the oven heating system or the spray application equipment.