SPIDER AS-FAN 8Q1911 - Caterpillar

Each cylinder has two inlet valves (10) and two exhaust valves (9) in the cylinder head. The inlet valves open when the piston moves downward on the inlet stroke. When the inlet valves open, cooled compressed air from the inlet port within the inlet manifold is pulled into the cylinder. The inlet valves close when the piston begins to move up on the compression stroke. The air in the cylinder is compressed and the fuel is injected into the cylinder when the piston is near the top of the compression stroke. Combustion begins when the fuel mixes with the air. The force of combustion pushes the piston downward on the power stroke. The exhaust valves open and the exhaust gases are pushed through the exhaust port into exhaust manifold (8). After the piston makes the exhaust stroke, the exhaust valves close and the cycle begins again.Exhaust gases from the exhaust manifold flow into the turbine side of turbocharger (5). The high pressure exhaust gases cause the turbocharger turbine wheel to turn. The turbine wheel is connected to the shaft that drives the compressor wheel. Exhaust gases from the turbocharger pass through exhaust outlet (4), through a muffler, and through an exhaust stack.Turbocharger
Illustration 3 g00291064
Turbocharger (typical example)
(1) Pipe
(2) Exhaust manifold
(3) Turbocharger Turbocharger (3) is mounted to exhaust manifold (2) of the engine. All of the exhaust gases go from the exhaust manifold through the turbocharger.
Illustration 4 g00291085
Turbocharger
(4) Air inlet
(5) Compressor housing
(6) Compressor wheel
(7) Bearing
(8) Oil inlet port
(9) Bearing
(10) Turbine housing
(11) Turbine wheel
(12) Exhaust outlet
(13) Oil outlet port
(14) Exhaust inlet The exhaust gases enter the turbocharger and the blades of the turbocharger turbine wheel are turned. Because the turbocharger turbine wheel is connected by a shaft to the turbocharger compressor wheel, the turbine wheel and the compressor wheel turn at very high speeds. The rotation of the compressor wheel pulls clean air through the compressor housing air inlet. The action of the compressor wheel blades causes a compression of the inlet air. This compression allows a larger amount of air to enter the engine. With more air in the engine, the engine is able to burn more fuel. The overall effect is an increase in power.When the load on the engine increases or when a greater engine speed is desired, additional fuel is injected into the cylinders. This creates more exhaust gases, which causes the turbine wheel and the compressor wheel to turn faster. Additional air is forced into the engine as the compressor wheel turns faster. The increased flow of air allows the engine to produce more power. The engine produces more power because the engine is able to burn additional fuel with greater efficiency.
Illustration 5 g00291087
Turbocharger with wastegate
(15) Canister
(16) Actuating lever The engine can operate under conditions of low boost. Low boost is a condition that occurs when the turbocharger produces less than optimum boost pressure. There is a spring that is inside canister (15). Under low boost, the spring pushes on the diaphragm in canister (15). This moves actuating lever