VTEC News

VTEC Jet Engine Cone Seal

A flight critical part fabricated from VTEC GF63 acts as the main oil seal on the front stage of jet aircraft engines. The part is bolted directly to the engine frame with NO GASKET. The oil is running at a normal operating temperature of 350°F (177°C) with excursions to 475°F (246°C). Testing was performed near the equator in Singapore where the highest sustained jet engine temperatures are recorded. To do this, VTEC passed the extremely stringent Hot, Wet, Open-Hole Compressive Strength Test of polymer matrix composite laminates without cracking. In another thermal test, no recordable weight loss was measured during Thermal Gravimetric Analysis (TGA) on VTEC at 932°F (500°C).

The coefficient of thermal expansion (CTE) of VTEC is so low — similar to ceramic — no leak occurs over the entire operating temperature range even though there is no supplemental sealing gasket. VTEC's outstanding dimensional stability further convinced designers that it is the logical choice. The part is truly flight critical; catastrophic engine failure will defiantly occur if the part would happen to fail. VTEC replaced an epoxy material in this application. Oil leaks, frequent maintenance and cracking were common with the former epoxy part.

VTEC GF63 is the approved part on the following military and commercial jet aircraft: F-16, F-18, KC135, Boeing 737, Boeing 757, Boeing 767, Boeing 777, and AirBus. In addition, RBI is proud to announce that Air Force One (President George Bush's aircraft) and Air Force Two (Vice President Dick Cheney's aircraft) have recently been retrofitted with engine oil cone seals made from VTEC.