Tadano TT-800XXL1, Service Manual

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F-4 F-4
Counterbalance Valve (Winch)
8
W 11 9-0500E
1 0 1 .Casing
1 5 1 .Plug
1 52.Plug
1 6 1 .O-ring
1 62.O-ring
1 63.O-ring
1 64.O-ring
1 65.O-ring
1 7 1 .Hex. socket head bolt
1 72.Square spring washer
20 1 .Cover
202.Cover
203.Spacer
204.Spacer
252.Air bleeder screw seat
253.Plug
256.Air bleeder screw
26
1 .O-ring
262.O-ring
27
1 .Hex. socket head bolt
272.Square spring washer
273.Hex. socket head bolt
274.Square spring washer
30
1 .Spool
302.Pilot piston
3
1 2.Steel ball
32 1 .Spring
322.Spring
35
1 .Orifice
354.Orifice
355.Orifice
36
1 .O-ring
362.O-ring
5
11 .Plunger
5 1 4.Seat
52 1 .Spring
55 1 .Plug
562.O-ring
563.Backup ring
600.Relief valve
Thread size and tightening torque
Tightening torque
Thread Thread size
N-m ft-lbf
1 5 1 , 1 52 G3/8 69 - 79 5 1 - 58
1 7 1 M 1 2 64 - 74 47 - 54
252 G 1 /4 34 - 38 25 - 28
253 G 1 /4 34 - 38 25 - 28
256 M 1 0 1 4 - 1 8 1 0 - 1 3
27 1 , 273 M 1 2 88 - 1 08 65 - 80
55 1 M33 1 8 1 - 2 11 1 34 - 1 56
600 M33 1 66 - 1 86 1 23 - 1 37
2. Function
2. 1 Balancing and holding functions
1 . During hoisting down, this valve selectively opens
and closes the motor outlet passage in
accordance with the pressure level of the motor
inlet pressure to control the speed of the load and
to prevent the load from falling under weight faster
than the hydraulic motor driving speed.
2. When the inlet pressure is below a certain level,
this valve closes the return passage to hold the
load at a desired position.
2.2 Overload relief function
When the circuit pressure rises above the preset
overload relief level, this valve vents it to protect
the circuit.