Hose Rupture Valves (Option); Boom Lowering After Hose Rupture - Volvo EC330B Operator's Manual

Hose rupture valves (option)

Hose rupture valves (option)
General
WARNING!
Do not dismantle the hose rupture valve yourself.
It is a pressure-loaded valve, if dismantling is attempted the
components inside the valve and which are under spring
tension may be expelled with great force causing personal
injury or injury to others.
Contact an authorized Volvo CE dealer workshop, if
problems occur.
Hydraulic oil is hot, poisonous and under high pressure.
Oil which jets out can penerate your skin and cause severe
injury. People who are injured by a jet of hydraulic oil need
medical attention at once.
S82184A
The hose rupture valves are mounted directly in the inlet port of
each boom cylinder.

Boom lowering after hose rupture

Never stand beneath a raised boom.
There are three cases when you have to lower the boom mechan-
ically.
1 Engine running
Lower the boom with the right operating lever in the usual way.
Collect the oil from the ruptured hose in a suitable vessel.
2 Engine stopped
The servo hydraulic pressure is maintained by a pressure accumu-
lator for a few minutes, which permits the operator to lower the
boom in the usual way. Do not wait too long to lower the boom, the
pilot pressure will reduce at a speed depending on your machine's
condition and equipment. Collect the oil from the ruptured hose in
a suitable vessel.
3 Engine stopped and no servo hydraulic pres-
sure
B A
1 Loosen lock nut (B) with a 13 mm spanner and turn adjusting
screw (A) with a 4 mm L-wrench counter-clockwise slowly.
Before turning the adjusting screw, mark its position to fa-
cilitate assembling later (pressure setting 365 kgf / cm)
The boom will then slowly be lowered to the ground.
S82184D
WARNING!
If the adjusting screw is screwed out completely, the oil
under pressure may cause personal injury, and an
uncontrolled boom drop
2 Turn adjusting screw (A) to its original position.
3 Hold adjusting screw (A) securely and tighten lock nut (B).
4 Contact an authorized Volvo CE dealer workshop.
Operating instructions
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