Flexible Cut-Out - ABB TPL85-B14 Operation Manual

4.6
4.6
CAUTION
CAUTION
© Copyright 2016 ABB. All rights reserved.
Operation

Flexible cut-out

Flexible cut-out
At low load, an engine that is being charged by several turbochargers can
be operated with one turbocharger shut down. Flexible shutting down or
switching on of a turbocharger is called "flexible cut-out". In flexible sys-
tems, slide valves or flaps are installed upstream of the gas inlet and
downstream of the air outlet of the turbocharger.
The lubricating oil supply of the shut-down turbocharger must not be
switched off because of engine vibration. To ensure that there are no oil
and gas leaks, this turbocharger must be supplied with sealing air.
A turbocharger may only be shut down or switched on if the engine is sta-
tionary or running "dead slow" (auxiliary blowers in operation). If switching
over results in turbocharger surging, a switch-over may only be carried out
with the engine is stationary until the cause has been eliminated.
Automatic switching of the flaps
During automatic flap control, there is a risk of the turbocharger rotating
opposite the intended direction of rotation if the air-outlet flap is open
further than the gas inlet flap during the switching process. This can
lead to damage on the turbocharger.
The turbocharger should only be switched on or off below charging

pressures of 0.3 bar.
Close the compressor outlet flap just before the gas inlet flap.

Manual switching of the flaps
If the gas inlet flap is opened during cut-out operation or the air-outlet
flap is closed during normal operation, this causes very high turbo-
charger speeds. These can result in damage with serious consequenc-
es or even a total loss of the turbocharger.
Never open the gas inlet flap during cut-out operation.

Never close the air-outlet flap during normal operation.

Operation Manual / TPL85-B14/-B15/-B16
4
4.6 Page 47