NASA Neutral Buoyancy Pool Recoat with Bio-Dur E560
DESCRIPTION
THE CHALLENGE: After over 20 years of hard service, the NASA Neutral Buoyancy Lab underwater coating needed a freshening up. During late 2017 the space agency had contracted with Underwater Construction Corporation to coat the North wall with BIO-DUR E560SW. After observing the result for almost two years the decision was made to continue coating the entire balance of the 24,000 sq.ft. vertical wall. NASA decided to apply the coating underwater while the pool remained in service because of the demanding astronaut training schedule and the heavy costs of draining the pool for repainting.
THE DIVING SOLUTION: Underwater Construction Corporation (UCC) mobilized a four-man team of diving professionals to finish the project. After an initial pressure washing to remove superficial surface contamination BIO-DUR E560SW packed in special plural component cartridges would be pumped to a diver in “deep dress” using a UCC developed pressure pad applicator to spread the coating on the walls. Mixing took place in a static mixer integral with the delivery system with delivery being controlled through communication between diver and a surface operator. This system ensured the pristine integrity of the pool and adjacent work areas was maintained throughout the project
Most of the wall surfaces were coated by a diver standing in an underwater “cage” which allowed free access to the wall while bracing the diver against its structure. This system gave maximum productivity by relieving the diver of vigorous movement.
The BIO-DUR E560SW product used was originally developed for underwater application to cathodically protected steel surfaces. These surfaces are difficult to coat underwater and require an especially surface tolerant and adhesive coating. BIO-DUR E560SW had been used many years before in the neutral buoyancy pool and had given excellent long-term results.
IMPLEMENTATION: A four-man dive team from UCC arrived in Houston to begin the last phase of the project; recoating the other three walls of the training pool. The last applications were made with the UCC application team worked in close harmony with the astronauts and their SCUBA equipped handlers.
