 Providing booths to the Air Force can present unique challenges including sizes not seen in commercial applications. This booth is large enough to accommodate a C-17 cargo jet.  One of 16 lifts conducted on a Sunday to avoid disruption of work schedules by other contractors.  3 of 24 reels providing chemical stripping agents and hot water rinse  Two Global strip booths side by side at Tinker. Each booth has 2 roll up doors at each end. Dual recovery and filtration systems are situated between the booths. Interior floors are concrete with high traction (.8 coefficient) urethane coating. Booths meet NFPA33 fire standards including integrated sprinkler system and meet Tinker bio and safety codes. Riveer’s booths and filtration equipment went in so flawlessly that Tinker has since awarded 5 more projects to Riveer for booths, air handling equipment, breathing air and decontamination showers.  Riveer recovery and filtration system, Cyclonator Deuce, with Micro Logics 1200 PLC controller and color panel view user interface.  Custom Global booth
Paint Prep Booths and Equipment, Tinker AFB, a Case History
The US Air Force has hundreds of billions of dollars invested in all manner or aircraft. From advanced fighter jets, to heavy lift cargo jets to unmanned drones. All of these “platforms” have highly specific lifecycle maintenance procedures and checks built into their programs.
As airline passengers we are all aware that the carriers take planes out of service for periodic FAA required engine inspections and tune-ups. To maximize their investments, the Air Force goes beyond commercial carriers and actually rebuilds their aircraft at specific intervals.
The US Air Force has built a complex for completely rebuilding aircraft at Tinker Air Force Base in Oklahoma City. At this facility aircraft are stripped down to the lowest possible components, examined, repaired or replaced, and rebuilt. Start to finish takes over 2 years.
As part of the rebuilding process, components are repainted using very exacting methods specified by the airframe manufacturers. Riveer, with its partner, Global Finishing Systems, was awarded a contract to provide two large booths for chemically stripping paint off of the airframe components prior to repainting. The booths each measured 45’W x 50’L x 22’H. They were constructed over the top of a custom concrete floor with live trenches continuously flushed with water. Riveer recycling equipment was used to capture and segregate paints and other contaminants while allowing the Air Force to reuse the chemical stripping agents.
The booths provided by Global included air handling equipment to provide 70 degree air into the room at 100 CFM. This massive amount of 70 degree air is provided whether the outside air is 10 degrees or 120 degrees. The air handling units were so massive they had to be placed on the roof with a special heavy lift helicopter.
Riveer called on its experience in the equipment washing industry to design a booth and processes for Tinker that dramatically improved the Air Force’s efficiencies. In Tinker’s old strip booth the “strippers” applied the chemical stripping agents with paint spray guns connected to pots that they pulled around on carts in the booth. In contrast, Riveer provided the strippers with fire fighting fog guns hanging on ceiling mounted reels. The chemistry is automatically mixed in a central tank next to the booth and the concentration is monitored to insure compliance with specs.
Hot water pressure washer guns hang down from more reels to provide easy access to rinse.
The floors of the booths have trenches with running water to carry the dissolved paint to the Cyclonator filtration system. The Air Force can reuse the chemicals reducing costs and a hazardous waste stream.
In addition to strip, scuff and paint booths, Riveer also provided Tinker with breathable air for operators, decontamination showers, and paint and chemical storage rooms. The strip and scuff booths both employed Riveer Cyclonator recovery and filtration equipment. Riveer also provided total electric hot water pressure washers.
Riveer as prime contractor with support from Global Finishing Systems met all delivery dates on budget.
Other features of interest with this installation included:
- 24 separate hose reels mounted to interior ceiling for chemical/water delivery
- 4 Total electric 3000 PSI @ 4GPM 140 degree hot water pressure washers
- Breathable air for 32 individual operators in 4 booths
- Trench works throughout the booths with rushing water to collect dissolved paints
- Three stage operations in each booth; plane naked, de-cote and rinse
Lessons Learned
- You can have 70 degree air from ambient at 100 CFM, but do you need it.
The most expensive piece of the Tinker Strip project was the air handling system. A strip booth needs to have 100 CFM of air but using outside fresh air is too expensive. For a tenth of the cost inside air with filtration could have been used without sacrificing quality or safety. The Air Force was trapped by some soon to be outdated specifications so had no choice. An interior air make up unit would avoid the expense of the helicopter lifts and the ongoing energy costs of heating or cooling ambient to 70 degrees.
- Breathable air can be class D, doesn’t have to be from oil less air compressor.
OSHA standards call for breathable air to be class D and there are specific filters and sensors that need to be employed to insure the safety of the air. However, older specification called for oil less air compressors which are more expensive and not as reliable. Again, the Air Force may have been caught by specifications that may need to be updated to meet current industry and OSHA standards.
- Stay with high end components and flexible PLC controls.
With complex systems changes are inevitable. Because the Global Finishing Systems and Riveer Environmental equipment all used Allen Bradley electrical components with programmable logic controllers, on site changes to parameters and functions were easy to accomplish and allowed the systems to be customized to Tinker’s preferences. The PLC’s also made interfacing between the systems for fire alarms, air quality alarms, and system integration relatively simple.
- Experience helps, desire to excel trumps.
Having significant experience in the chemical pretreatment and water filtration market is important in projects like this, but even better is to find a company that understands partnering and is invested in the success of the project. Partnering is a two way street. Find a company you can trust, and then trust them to advise you.
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