Blast and spray facilities for aluminium and mild steel structures
A large aerospace and defence group
To assess a blast and spray operation and radically improve throughput without completely replacing existing facilities
Following the success of our surface preparation and painting facility for Boeing 747-sized aircraft in Cambridgeshire (detailed in a previous case study), Airblast Eurospray was asked to assist on a project that involved building semi-permanent logistics facilities.
The aim was to create a more efficient process for blasting and coating a high volume of temporary structures designed to accommodate machinery and personnel. The frames of these portable facilities were made from aluminium and mild steel independently, which needed to be abraded to achieve a surface profile of 75 microns and, for mild steel, a surface cleanliness of SSPC-SP-10 or SA2 ½ and then coated.
Airblast suggested six key changes which would completely overhaul the current system and drastically increase the facility’s productivity.
1. By re-engineering the electrical controls of the existing spray booth and adding an insulated roller door, Airblast was able to convert a single spray facility into two 10 m long spray rooms – each of which could be operated independently of the other.
Not only did this mean that two products could be sprayed at once, but it also meant that one product could be sprayed while another was simultaneously baked. Furthermore, the electrical modifications ensured that the two halves were not permanently separated but could still be combined to create one long spray booth if required.
2. Airblast installed two blast rooms on site to enable the client to switch from hand abrading to a faster, safer grit blasting system.
When preparing surfaces for coating, the client in question was accustomed to hand abrading every surface, which was a time-consuming and labour-intensive process. Now, they are able to prepare an entire unit in one hour using grit blasting – a dramatic improvement on their previous system. Additionally, the team also found that paint adhesion was improved on surfaces that had been blasted, rather than hand abraded.
When DAing, it’s necessary for operators to take regular breaks to avoid Hand-Arm Vibration Syndrome (HAVS), also known as Vibration White Finger (VWF). Grit blasting isn’t subject to the same restrictions, meaning operators can continue to work for longer periods in a safer, more comfortable environment. This allows our clients to achieve striking improvements in efficiency and a rapid return on investment.
3. To avoid interruptions, each blast room was fitted with an Airflex Recovery Floor system, which would recover and recycle media automatically. These allow the operator to keep blasting on an uninterrupted basis.
4. The client needed to process a high volume of aluminium and mild steel surfaces. Following trials, the abrasive media chosen were stainless steel grit and hardened steel grit.
Hardened steel grit is typically used for surface cleaning, preparation, and the finishing of non-ferrous metals. In the past, the most popular media for these surfaces were friable abrasives such as aluminium oxide. These quickly break down, resulting in dust that affects visibility and can settle on surfaces, potentially affecting the finish. Hardened steel grit is a cleaner alternative that creates far less dust, resulting in less time spend on clean-up and a higher quality finish.
5. Airblast created a new control system for managing the ventilation, spray, and bake modes. This gave staff an intuitive interface for controlling each half of the spray facility independently, making it easy to switch from spray to bake mode when required.
The ability to spray in one end of the room and bake in the other simultaneously – without the temperature in one half affecting the other – greatly increased the potential productivity of the facility.
6. In each blast room, Airblast installed a Blast Lift – a pneumatically powered, blast-proof platform. In place of the pneumatic rams found in a traditional scissor lift, the Airblast Blast Lift uses inflatable bags. It has a working height of up to 4 metres and a weight capacity of up to 250kg with a smooth raising and lowering operation. It is also easy to reposition, giving it all the benefits of a traditional scissor lift without the vulnerabilities.
Airblast’s design ingenuity gave a new lease on life to an existing surface preparation and finishing facility. As a result, our client was able to meet the increased demand without having to invest in an all-new setup.
Also, by replacing hand abrasion with grit blasting, the client was able to achieve better surface preparation in far less time – an improvement that was aided by the introduction of the Airblast Blast Lift.
Although many companies still rely on hand abrading, we find that most of our clients stand to make significant savings in both time and money by switching to grit blasting. Some of our customers have even cut their processing times by a factor of eight by installing a blast room, resulting in a marked improvement in their output. To learn more about Airblast blast room technology, see our blast rooms page or contact us below.