SOFTWARE GP-POWER TRAIN 3520552 - Caterpillar

STEERING COMPONENTS
1. Left steering cylinder. 2. Oil line. 3. Rear frame. 4. Left steering cylinder rod. 5. Front frame. 6. Junction. 7. Oil line. 8. Hydraulic oil pump. 9. Oil line from pump to control valve. 10. Oil line. 11. Oil line. 12. Steering control valve. 13. Return line to tank. 14. Steering control valve spool. 15. Oil line. 16. Right steering cylinder. 17. Junction. 18. Drain line from steering control valve. 19. Oil line. 20. Hydraulic oil supply tank. 21. Right steering cylinder rod.The head ends of the cylinders are mounted to the rear frame and the cylinder rods are attached to the front frame. The cylinders pull and push the front frame from side to side to produce the required turning angle.When making a right turn, oil is directed to the head end of the left steering cylinder and the rod end of the right steering cylinder. The left cylinder rod extends and the right cylinder rod retracts, moving the front frame to the right. When making a left turn, the oil flow is reversed.
STEERING COMPONENTS
6. Junction. 7. Oil line. 8. Hydraulic oil pump. 9. Oil line from pump to control valve. 10. Oil line. 11. Oil line. 12. Steering control valve. 13. Return line to tank. 14. Steering control valve spool. 15. Oil line. 17. Junction. 19. Oil line. 22. Follow-up linkage. 23. Steering gear assembly.Flow Of Oil In Neutral Position
When control valve spool (20) is in NEUTRAL (centered position), the vehicle is not steering. Oil pressure in steering cylinders (1 and 2) is equal because of the small amount of pump oil from passage (14) flowing through slots (A) into ports (12 and 16) which lead to the steering cylinders.
STEERING SYSTEM IN NEUTRAL POSITION
1. Steering cylinder. 2. Steering cylinder. 3. Linkage. 4. Gear sector. 5. Gear nut. 6. Lever. 7. Steering shaft worm. 8. Follow-up linkage.The equal pressure in both cylinders eliminates erratic steering cylinder operation. A small amount of oil is allowed to circulate through control valve spool unloading slots (18) to the cylinders to compensate for steering shock.Oil from the pump enters the valve body through passage (14). With control valve spool (20) in NEUTRAL position, the valve spool blocks most of the oil flow to cylinder ports (12 and 16).Oil pressure overcomes the force of springs (17), moving valve (13) to the left. As valve (13) moves, passage (11) is opened to tank and pump oil is returned to the supply tank.
FLOW OF OIL IN NEUTRAL POSITION
9. Spring. 10. Chamber. 11. Return passage to oil tank. 12. Outlet port to cylinder. 13. Valve. 14. Inlet passage from oil pump. 15. Spacer. 16. Outlet port