Case CX290B - Hydraulic System

Lep SM290B1002-1NA Issued 01-2010
1002-12
Hydraulic system
Hydraulic pump drive system, directly coupled to the engine (no transmission)
Main pump
Manufacturer............................................................................................................................................... Kawasaki
Pump type .............................................................................................. double variable displacement piston pump
Displacement volume ................................................................................................ 136.7 cm
3
(8.34 cu in) x 2 /rev
Rated operating pressure .......................................................................................................... 34.3 MPa (4975 psi)
Maximum operating pressure .................................................................................................... 37.3 MPa (5410 psi)
Input revolution speed.............................................................................................................................. 1800 min-1
Maximum discharge flow .............................. 246 L/min (64.99 gpm) x 2 / 243 L/min (64.19 gpm) x 2 at 1800 min
-1
Pilot pump
Pump type ............................................................................................................................................... Gear pump
Displacement volume ............................................................................................................ 15 cm
3
(0.91 cu in)/rev
Operating pressure ...................................................................................................................... 3.92 MPa (568 psi)
Maximum flow................................................................................................... 27 L/min (7.13 gpm) (at 1800 min
-1
)
Input horsepower ............................................................................................................................................ 2.8 kW
Control method
Hydraulic simultaneous constant output control.
Maximum flow adjustment control through external commands (negative control).
Setting horsepower adjustment control through external command current.
Control Valve
Model; 4-spool section: integrated (1) or 5-spool section: integrated (1)
Operation method: hydraulic pilot method: travel, swing and operating machine
Maximum flow .......................................................................................................................... 243 L / min (64.19 gpm)
Main relief set pressure........................................... standard; 34.3 MPa (4975 psi), power boost 37.3 MPa (5410 psi)
Overload set pressure..................................................................when boom down; 29.4 ± 0.5 MPa (4264 ± 72.5 psi)
.............................................................................................................................................other: 39.2 MPa (5685 psi)
Foot relief set pressure ............................................................................................................... 2.55 MPa (369.85 psi)
Functions
Straight travel circuit
Boom up / arm 2 pumps internal flow
Boom and arm load holding circuit
Boom-down regenerative circuit
Bucket-close regenerative circuit
Arm-in forced regenerative circuit
Swing priority variable orifice (for arm operation)
2 pumps flow
Variable foot relief
Hydraulic Cylinders
Boom cylinder (x2)
Cylinder bore .............................................................................................................................Ø140 mm (Ø5.51 in)
Rod diametre ...............................................................................................................................Ø95 mm (Ø3.74 in)
Maximum retracted lenghth ........................................................................................................ 1918 mm (75.51 in)
Stroke ......................................................................................................................................... 1369 mm (53.90 in)
Arm (dipper) cylinder
Cylinder bore .............................................................................................................................Ø150 mm (Ø5.90 in)
Rod diametre .............................................................................................................................Ø105 mm (Ø4.13 in)
Maximum retracted lenghth ........................................................................................................ 2205 mm (86.81 in)
Stroke ......................................................................................................................................... 1569 mm (61.77 in)
Bucket cylinder
Cylinder bore .............................................................................................................................Ø135 mm (Ø5.31 in)
Rod diametre ...............................................................................................................................Ø90 mm (Ø3.54 in)
Maximum retracted lenghth ........................................................................................................ 1692 mm (66.61 in)
Stroke ......................................................................................................................................... 1078 mm (42.44 in)