To support the fleet's higher operational pace, along with accelerated wear and tear on Navy and Marine Corps aircraft, Fleet Readiness Center Southeast (FRCSE) is expanding its manufacturing capabilities by using technologically advanced equipment, such as vertical and high-speed grinders and precision measuring machines, to ensure reliable power for the military's high-performance aircraft.
From shore-based aircraft like the P-3 Orion maritime patrol aircraft powered by four Allison T-56-A-14 engines with propellers to the carrier-based F/A-18 Super Hornet attack fighter powered by two internal F414-GE-400 turbofan engines - the these power plants must be in tiptop shape to support any mission.
Carl Finger, engine machine shop supervisor in the FRCSE Crinkley Engine Facility at NAS Jacksonville, said these power plants are staying on the aircraft longer than ever before. He said the engines division has a dedicated machine shop to rework worn parts to like new condition.
"Our new equipment is producing better engine performance, saving time and giving Warfighters improved mission capability," said Finger. "The high speed grinding technology integrated with laser measuring creates a more accurate final product in less time.
FRCSE purchased two Reform High Speed Blade Tip Grinders, that each turn at 3,000 revolutions per minute.
Finger said the high speed technology allows artisans to grind blade tips on the same axis of rotation that the rotors spin to simulate engine conditions.
The engine blades must rotate at high speeds to counteract the force of the grinder. The high-speed feature allows the blades to extend fully during the grinding process for better results.
It is essential that engine blades be machined evenly. Unbalanced grinding can make a blade heavier on one side than on the other, which can lead to heavy vibration, the loosening of internal structural bolts, accelerated engine wear or even failure.
The Reform grinder measures every blade at every stage of production with laser technology to ensure grinding accuracy.
The machines grind high pressure compressor rotor blades from a TF34-GE-100 turbofan engine thata powers the Air Force A-10 Thunderbolt II and the Navy's S-3 Viking aircraft.
In addition, the machine supports the F404-GE-402 engine that powers the F/A-18A-D Hornet with 17,700 pounds of static thrust per engine, and the F414-GE-400 turbofan engine that powers the Super Hornet and the EA-18G Growler Airborne Electronic Attack aircraft. Each engine is capable of producing 22,000 pounds of static thrust according to the Navy Fact File.
Another technology solution FRCSE is utilizing is the DANOBAT Vertical Grinder to machine stationary engine components like stator cases. It replaces the Pope Grinding Spindle with its outmoded manual dial indicator and the Electronic Run-Out Machine (EROM) used to perform pre- and post-production measurements.
"I was happy to see that go," Finger said of the EROM. "It did really good on the rotors, but when we converted to laser measurements it never really worked. It was touchy; it gave us problems."
The high-precision DANOBAT integrates different machining options for a wide range of engine components. The machine uses touch probes to provide induction measurements thus ensuring parts can be held to diametric tolerances that can be machined.
FRCSE performs out-of-airframe testing on all jet engines repaired at the facility to ensure maximum reliability and performance to the Fleet.
The computer-controlled test cells have a thrust capacity of 40,000 pounds and a bed capacity of 100,000 pounds.
All engines are tested through their entire operating range in both automated and manual modes to verify oil pressure, exhaust, gas temperature, vibration, speed, and bearing-vent pressure.