CORE AS 2W7002 - Caterpillar

Illustration 1 g03876527
Air inlet and exhaust system
(1) Air-to-air aftercooler (ATAAC)
(2) Exhaust manifold
(3) Turbocharger
(4) Clean Emissions Module (CEM)
(5) NOx Reduction System (NRS) cooler
(6) NRS venturi
(7) NRS valve
(8) Exhaust valve solenoid
(9) Intake manifold
(10) Cylinder headThe engine has an electronic control system. The system controls the operation of the engine and communicates with the Clean Emissions Module (CEM) Aftertreatment Electronic Control Module (ECM). The CEM consists of the following components: Diesel Particulate Filter (DPF), Selective Catalytic Reduction (SCR), and systems.The system consists of the following components:
Electronic Control Module (ECM)
Wiring
Sensors
ActuatorsInlet air is pulled through the air cleaner . The inlet air is then compressed and heated by the compressor wheel of turbocharger to about 150 °C (300 °F). The inlet air is then pushed through air-to-air aftercooler core and the inlet air is moved to the air inlet elbow. The temperature of the inlet air at air inlet elbow is about 43 °C (110 °F). Cooling of the inlet air increases the combustion efficiency. Increased combustion efficiency helps to lower fuel consumption. Also, increased combustion efficiency helps to increase horsepower output.Aftercooler core is a separate cooler core. The aftercooler core is installed in front of the core of the engine radiator. Air that is ambient temperature is moved across the aftercooler core by the engine fan. The aftercooler core cools the turbocharged inlet air.From aftercooler core , the air is forced into the cylinder head to fill the inlet ports. Air flow from the inlet port into the cylinder is controlled by the inlet valves.
Illustration 2 g01880505
Air inlet and exhaust system
(11) NRS cooler
(12) Exhaust manifold
(13) Aftercooler
(14) Exhaust outlet from turbocharger
(15) Turbine side of turbocharger
(16) Compressor side of turbocharger
(17) Air inlet
(18) Inlet valve
(19) Exhaust valveThere are two inlet valves and two exhaust valves for each cylinder. Inlet valves open when the piston moves down on the inlet stroke. When the inlet valves open, cooled compressed air from the inlet port is pulled into the cylinder. The inlet valves close and the piston will move up on the compression stroke. The air in the cylinder is compressed. When the piston is near the top of the compression stroke, fuel is injected into the cylinder. The fuel mixes with the air and combustion starts. During the power stroke, the combustion force pushes the piston downward. After the power stroke is complete, the piston moves upward. This upward movement is the exhaust stroke. During the exhaust stroke, the exhaust valves open, and the exhaust gases are pushed through the exhaust port into