Conventional sand blasting (below) is labor intensive
The EnvirobotTM system (above) offers a high-tech solution. Above image courtesy of Chariot Robotics, LLC.
The conventional method of grit blasting creates toxic airborne
dust during the blasting as well as 40 lb. of toxic waste
per square foot cleaned. This endangers shipyard workers and
creates an expensive disposal problem. The grit-based method
also drives grit into the hull surface where it decreases
the adhesive properties of the paint. While single-stream
high-pressure water guns are also used, they remove paint
very slowly and do nothing to contain toxic marine paint run-off.
The EnvirobotTM robotic system uses ultra-high-pressure
water jets (55,000 psi) to strip the hull down to bare metal.
Multiple nozzles in a spinning head remove coatings in a wide
swath, not inch by inch. It can remove coatings at
a rate of 500 to 3000 square feet per hour, depending on how
many layers of the coating are being removed.
Magnets hold it securely and enable it to roll almost
anywhere. All the water used in the stripping is recovered
by a powerful vacuum system and recycled. The only residue
of the cleaning is the paint itself, which is automatically
dumped into containers for proper disposal.
Moreover, the water-based stripping process produces a much
cleaner metal surface, which greatly increases the life of
the paint applied to the ship. Compared to any form of sand-
or grit-blasting, a hydroblasted surface is easily proven
to rust less, and to allow paint to adhere better.