Hardi COMMANDER DELTA FORCE, Instruction Book

Page: 179 / 218

6 - Maintenance
179
Yaw Damping
The unfolded spray boom will create yaw movements, when
•
driving over uneven terrain
•
turning on headland
•
speeding up
•
braking.
The three accumulators located in the boom centre act as dampers for
the yaw movements, when driving in the field.
Damping Function
Each accumulator contains nitrogen gas and hydraulic oil, separated by a diaphragm. When the boom makes a yaw
movement, hydraulic oil will be transferred into the accumulator. The oil pushes the diaphragm while compressing the gas.
When this compression overcomes the oil pressure from the boom, the boom wing is moved back to its original position
dampened by the oil flow in the circuit.
Accumulator Service
If the yaw damping seems to be insufficient, the accumulators needs to
be recharged or replaced. Ask your HARDI dealer to assist you.
1.
Check for any leaks.
2.
Check pressure setting for the accumulators in the test sockets,
which are located in the hydraulic block (A). Hydraulic hoses for the
accumulators are also connected to this block.
3.
Fill nitrogen gas (N
2
) into the accumulators:
Gas pressure = 12 bar -0/+2 for booms of 24-28 meters.
Gas pressure = 18 bar -0/+2 for booms of 30-39 meters.
The gas volume in the accumulator is approx. 0.5 litres.
4.
Fill hydraulic oil into the accumulators:
Oil pressure = 20 bar -0/+2 for booms of 24-28 meters.
Oil pressure = 35 bar -0/+2 for booms of 30-39 meters.
€
DANGER! Do not fill the accumulators with other gases, such as air or pure oxygen. Risk of explosion.
μ
ATTENTION! The accumulators are automatically pressurized at
35 bar, when the boom is unfolded.