TIP GP-WHEEL 2572553 - Caterpillar

Illustration 1 g03719232
Front view of the main control valve
(1) Stick drift reduction
(2) Pilot port
(3) Drain port The stick drift reduction valve is placed in the stick circuit between the main control valve and the stick cylinder. When the joystick for the stick is in the NEUTRAL position, the stick drift reduction valve stops oil leakage from the rod end of the stick cylinder. Stopping oil leakage prevents stick drift.Stick Out
Illustration 2 g03711846
Stick drift reduction valve (STICK OUT)
(1) Stick drift reduction valve
(2) Port
(3) Drain port
(4) Port
(5) Passage
(6) Valve
(7) Spring chamber
(8) Passage
(9) Drain passage
(10) Spool
(11) Passage
(12) Spring
(13) Port
(14) Stick I control valve
(15) Spring chamber
(16) Plug During a STICK OUT operation, pilot oil is not sent from the pilot control valve to port (2) of stick drift reduction valve (1). Spool (10) does not shift.The oil flow from the stick I control valve enters port (4) and combines with the oil from the stick II control valve. The combined oil flow flows into passage (5). As the oil pressure in passage (5) increases, valve (6) shifts against the force of spring (12). The oil in spring chamber (7) flows through passage (8), spool (10) and passage (11) to port (13). The oil delivery in passage (5) now flows through port (13) to the rod end of the stick cylinder.Stick In
Illustration 3 g03711847
Stick drift reduction valve (STICK IN)
(1) Stick drift reduction valve
(2) Port
(3) Drain port
(4) Port
(5) Passage
(6) Valve
(7) Spring chamber
(8) Passage
(9) Drain passage
(10) Spool
(11) Passage
(12) Spring
(13) Port
(14) Stick I control valve
(15) Spring chamber
(16) Plug When the joystick is moved to perform a STICK IN operation, pilot oil is sent from the pilot control valve to port (2) of stick drift reduction valve (1). Spool (10) shifts down until the spool contacts plug (16). The oil in spring chamber (7) flows through passage (8), spool (10), spring chamber (15), and drain line (9) to the hydraulic tank.The return oil from the stick cylinder rod end enters port (13). Since the pressure in spring chamber (7) is low, the oil in port (13) shifts valve (6) against the force of spring (12). The oil from the rod end of the stick cylinders flows through port (13), passage (5) and port (4) to the stick I control valve.Stick Hold
Illustration 4 g03711871
Stick drift reduction valve (STICK HOLD)
(1) Stick drift reduction valve
(2) Port
(3) Drain port
(4) Port
(5) Passage
(6) Valve
(7) Spring chamber
(8) Passage
(9) Drain passage
(10) Spool
(11) Passage
(12) Spring
(13) Port
(14) Stick I control valve
(15) Spring chamber
(16) Plug When the joystick is returned to the NEUTRAL position, the stick cylinder is held in the OUT position. No pilot oil is supplied to port (2) and piston (10) does not shift downward. Oil in passage (8) cannot drain to the hydraulic tank.With the stick suspended above the ground, the weight of the stick creates pressure on the rod end of the cylinder. Oil pressure increases in passage (11), passage (8), and spring chamber (7). This action causes valve (6) to shift to the closed position. Oil can no longer flow from the rod end of the