CORE AS-OIL COOLER 2994247 - Caterpillar

Illustration 1 g01149409
Tandem Pump Arrangement (Implement) (A) Rear Pump. (B) Front Pump.The implement pump is two pumps in tandem. Front pump (B) is a variable displacement piston pump. Rear pump (A) is a fixed displacement piston pump. Each pump is capable of producing an equal amount of displacement. Both pumps receive hydraulic oil from the same hydraulic tank. Rear pump (A) supplies oil to the right main control valve. Front pump (B) supplies oil to the left main control valve. The rotation of the shaft is counterclockwise when the rotation of the shaft is viewed from the drive end.
Illustration 2 g01150272
Cross Section View (1) Swashplate (2) Shoe plate (3) Bearing (4) Spring (5) Minimum displacement adjustment screw (6) Maximum displacement adjustment screw (7) Piston (8) Barrel assembly (9) Port plate (10) Shaft (11) HeadThe pump rotates when the engine is activated. The pump drive rotates shaft (10) . Pistons (7) , barrel assembly (8) , and shoe plate (2) rotate at the same speed as the shaft. Swashplate (1) and port plate (9) do not rotate. Oil from the hydraulic oil tank flows into pump head (11) at the inlet passage. The oil flows through inlet passages in port plate (9) . As drive shaft (10) turns, the openings of the cylinder barrel move by the inlet passages of port plate (9) .Each piston (7) inside cylinder barrel (8) is held against swashplate (1) by shoe plate (2) . The angle of swashplate (1) is controlled by minimum displacement adjustment screw (5) and maximum displacement adjustment screw (6) .As pistons (7) follow the angle of swashplate (1) , the pistons move in and out of cylinder barrel (8) . When a piston (7) moves out of cylinder barrel (8) , oil is pulled in behind the piston.The angle of swashplate (1) determines the amount of oil that is drawn into each cylinder barrel (8) . As the barrel assembly continues to rotate, the swashplate angle pushes the pistons into the barrel.The pistons push oil out of cylinder barrel (8) through the outlet passages in port plate (9) . The angle of the swashplate determines the amount of oil that is pumped out of each cylinder barrel (8) for each drive shaft rotation.The force of spring (4) holds the barrel assembly against port plate (9) . The smooth surfaces of barrel (8) , head (11) , and port plate (9) create a metal-to-metal seal between the port plate and the barrel assembly. This seals the inlet port from the outlet port. Any wear to the surfaces will decrease the efficiency of the pump.