Patented CT-R 360 Dynamic Journal Bearing Turbocharger
In addition to the very successful Triplex Ceramic ball bearing system that imparts very rapid acceleration to the turbocharger rotors, Comp Turbo also produces turbochargers that have conventional floating sleeve bearing systems. The sleeve bearing systems have been used in commercial turbochargers for decades and consist of two floating sleeve bearings, spaced apart axially and the bearings are free to rotate in the bearing housing bore. They are accompanied by a stationary thrust bearing that carries rotor thrust forces in both axial directions.
The floating sleeve bearings are supplied with lube oil ducted from the engine lube oil system to the turbocharger bearing housing. The lube oil is fed separately to each of the sleeve bearings inner and outer clearance spaces, and these oil films not only lubricate the bearings but also provide cushioning against shock and vibration from external sources. The thrust bearing has a separate oil feed that supplies pressurized oil to both thrust faces.
The lube oil supply from the engine should be a value between 35 psi minimum to 85 psi maximum. The 35 psi minimum is necessary to properly lubricate the system. The 85 psi maximum is a limitation to prevent oil leakage past the piston ring seals in the turbocharger due to excessive lube oil flow.
As previously stated, the floating sleeve bearing systems provide a very satisfactory service life, proven by the many years of use in commercial turbochargers. Both ball bearing and sleeve bearing systems are available in Comp Turbo turbochargers and selection is a matter of customer preference.