The OMAX waterjet cutting tool is typically used by FRCSW in manufacturing skins, angles and ribs for the F/A-18, E-2/C-2 and H-60 airframes. (US Navy photo.)
Fleet Readiness Center Southwest (FRCSW) artisans use a variety of tools and unique machinery in their daily work to provide the fleet with mission-ready aircraft. One such machine, the waterjet, which is assigned under the industrial manufacturing program in Building 472, has the ability to cut aircraft wings in half. With a 30-horsepower water pump and able to accommodate parts and materials up to 6 feet by 12 feet in its water tank, there's not too much the manufacturing cutting tool can't cut, curve, or shape.
An abrasive waterjet, the unit uses a combination of high pressure water and an 80-grit garnet abrasive that travels through a water line to cut material. Water enters a filtration system to a pump which boosts it up to 50,000 psi, and then sends it to a nozzle which has a mixing chamber where the abrasive is introduced. The abrasive grit collects at the bottom of the water tank where it is captured and disposed of as hazardous material. The 80-grit abrasive is about the size of beach sand and is typically used for making rough cuts. Finer grits of abrasive are used for making more precision cuts to create intricate parts. An abrasive waterjet can cut through a variety of materials including stone, wood, titanium, and Teflon.
Unlike lasers, which FRCSW uses for cuts and patterns from minimally thick pieces of steel and aluminum, the waterjet does not use heat, sparing metals and other substances from the potential damage or intrinsic property changes associated with heat-cutting devices.
Operation of the machine begins with an AutoCAD (Computer Aided Design) that interprets the blueprints of the part to be manufactured or cut. AutoCAD results are transferred to the waterjets computer terminal which estimates the time to complete the job, an estimate of the cost, and the amount of abrasive required based upon the material used and its thickness. The FRCSW waterjet can handle thicknesses of up to 18 inches.
Manufactured by the OMAX Corp., FRCSW purchased the machine in mid-2009 to replace its aging unit. The waterjet is routinely used to cut out F/A-18, E-2/C-2, and H-60 Sea Hawk helicopter parts including skins and ribs for the airframes.