TECHNICAL BROCHURE 1
INTRODUCTION The development of turbochargers (TC) is of particular interest due to the need for low consumption and very low emission diesel and gasoline engines. Downsizing of engines is closely associated with the development of new components that must handle increasing exhaust gas temperatures, leading to the use of advanced materials and technologies for the design of TC bearings. TC-Lube is a separate lubrication system dedicated to the development and testing of turbochargers (TC). It includes programmable temperature and pressure regulation systems. TC-Lube allows lubrication of turbochargers independently from the engine block. It can be used as a stand alone unit that regulates automatically oil temperature and flow in the turbocharger. These parameters can also be regulated externally through a test rig / test bed control system. TC-Lube can also be combined to on-line measuring tools for monitoring oil consumption (turbine stage and compressor stage, independently), fuel dilution, oil aeration and bearing wear. TC Lube equipment installed in a test cell 2
RANGE OF APPLICATIONS TC-Lube can be used for the following purposes: To lubricate a turbocharger independently from the engine. The turbocharger can be lubricated with a different oil formulation from the engine oil, at a different pressure, and/or at a different temperature; To study oil consumption issuing from the turbocharger only. TC Lube can be coupled to C-Lube equipment for on-line measurement of oil consumption associated to the compressor stage and/or to the turbine stage. Various types of lubricants can be used to study the impact of their formulation on oil consumption; To study turbocharger bearing wear. TC Lube can be coupled to the TLA/RNT equipment for on-line monitoring of turbocharger bearing wear independently from the rest of the engine. Thin sand particles and/or diluted oil can also be added into the TC lubrication circuit to study their impact on bearing wear, without damaging the engine; To investigate lubrication limits. Combination of a TC-Lube system with on-line wear measuring tools make it possible to determine the minimal oil pressure conditions needed at various operating conditions: continuous operation or during specific cycles such as Stop & Start cycles. TC-Lube is compatible with other tools such as C-Lube equipment for on-line oil consumption measurement of turbochargers, Air-X equipment for monitoring lubricant aeration, and TLA-RNT tools for on-line bearing wear measurement. OPERATING PRINCIPLE Oil that lubricates the turbocharger (TC) is contained in a main tank. Oil supply is performed using a pump with variable speed and oil pressure is accurately regulated, based on a preset value or on an external parameter issuing from the test bench control system or from a pressure transducer installed in the engine gallery A dual loop oil circuit is used to regulate oil temperature. The oil constantly circulates between the main tank and two heat exchangers - one for heating up and the other one for cooling down, assuring accurate temperature regulation and very fast response. Oil that feeds the turbocharger: It is heated up when it passes through the first heat exchanger. The heating circuit includes a unit where special oil is heated by resistors up to 200 C. This high temperature grade oil is sent to the heat exchanger where heat transfer to the secondary loop is accurately controlled through a variable speed pump. Such configuration prevents from oxidising the oil that lubricates the turbocharger; Cooling down is performed through a water/oil heat exchanger where cold water is circulated through a motorized valve. The oil temperature set point is regulated based on a local preset value or on an external parameter supplied by the test bench control system. 3
OIL PRESSURIZATION AND TEMPERATURE SET POINT The device includes: A regulation system for fine control of oil pressure in the turbocharger; A regulation system for maintaining oil temperature constant at +/- 0.5 C, in a range between 40 and 150 C TC-LUBE schematic OIL CONDITIONING LOOP TURBOCHARGER OIL CIRCUIT HEATING CIRCUIT TURBOCHARGER OIL TANK TURBO CHARGER ENGINE HEATING UNIT (tank with heaters) H.E. FOR OIL HEATING Heating pump Coolant input Conditioning pump H.E. FOR OIL COOLING Turbocharger pump COOLING CIRCUIT M Coolant output Motorized valve Oil pressurization and temperature regulation systems The dual loop heating system offers the following benefits: No direct contact with resistors means that oil that feeds the turbocharger is not degraded, even when test duration is high; This design allows measuring accurately the blow-by gas flow issuing from the turbocharger. A blow-by meter can be easily installed; The oil contained in the secondary loop feeds the turbocharger. It is designed in such a way that oil volume is minimal. 4
1. «TC-LUBE» HARDWARE TURBOCHARGER OIL TANK HEATING UNIT ELECTRIC CABINET MOTORIZED VALVE (FOR COOLING) Front side of the cart The turbocharger oil tank is situated at the lower level of the cart. Drain plugs are easy to access and oil circuits are quickly drained. Both tanks (containing turbocharger oil and heat transfer oil) are covered with insulating material to minimize heat losses and energy consumption. The electric cabinet contains the Programmable Logic Controller (PLC), the pump controllers, the heater controllers, two PID regulators, and the electric breakers. It includes communication tools with the test bench control system (i.e. temperature and pressure set points). 5
HEATING PUMP H.E. (COOLING) H.E. (HEATING) TC PUMP CONDITIONNING PUMP Rear side view of the cart (electrical cabinet removed) PLC CONTROLLER PUMPS CONTROLLERS TC OIL PRESSURE SETPOINT TC OIL TEMPERATURE SETPOINT Electric cabinet - outside view 6
HYDRAULIC SET-UP - CONNECTION TO THE TURBOCHARGER TC-Lube installed in a test cell for turbocharger development tests Genuine oil supply (locked) Oil supply from TC- Lube Genuine oil return (locked) Temperature sensor T et Oil return to TC- Lube Pressure sensor p et TC-Lube hydraulic connection to the turbocharger 7
For more information: DSi - Delta Services Industriels SPRL Rue Mont d Orcq, 3 B-7503 Froyennes BELGIUM Tel: +32 69 64 06 04 Fax: +32 69 78 00 79 Web site : www.deltabeam.net e-mail : infos@deltabeam.net 8