HOSE 2858862 - Caterpillar

Illustration 1 g06283074
Travel counterbalance valve
(1) Crossover relief valve
(4) Piston
(7) Spool
(10) Crossover relief valve
(11) Check valve
(12) Passage
(13) Check valve
(14) Left travel motor
(16) Passage
(17) Spring chamber
(18) Counterbalance valve
(19) Spring chamber
(20) Spring
(21) Passage
(23) Passage
(24) Passage
(26) Port
(27) Passage
(28) Passage
(29) Passage
(30) Port
(31) Passage
(34) SpringThe travel counterbalance valve consists of counterbalance valve (18), crossover relief valve (1), and crossover relief valve (10). The travel counterbalance valve is bolted to travel motor (14). The travel counterbalance valve has the following four functions.
The travel counterbalance valve prevents a shock load when travel is stopped.
The travel counterbalance valve prevents overspeed while the machine is traveling down a slope.
The travel counterbalance valve prevents cavitation.
The travel counterbalance valve routes a portion of the oil to the travel parking brake in order to release the brake.Counterbalance Valve Operation During Level Travel
Illustration 2 g06281616
Left travel motor and travel brake valve
(1) Crossover relief valve for reverse travel
(10) Crossover relief valve for forward travel
(14) Left travel motor
(18) Counterbalance valve
(26) Port
(30) PortCounterbalance valve (18) consists of crossover relief valve (1), crossover relief valve (10), check valve (11), check valve (13), spring (20), and spring (34). All of these components are located in counterbalance valve (18). During forward travel on level ground, pump oil is supplied to port (26). The oil flows from port (26) through passage (23) to check valve (11) in spool (7). The pressure oil forces check valve (11) to open. Oil flows through passage (24) to motor (14) in order to drive the motor.A portion of the oil delivery from the left pump in port (23) flows past check valve (11) through passage (21) and passage (12). The oil proceeds to flow into spring chamber (17). The oil in spring chamber (17) pushes spool (7) to the right against the