Metso MP1000, Technical Reference Manual

Page: 140 / 180

SECTION 3 - M. FRAME, ADJ. RING, TRAMP REL. & CLRNG JACK ASSY
3-22
MP SERIES CONE CRUSHER TECHNICAL REFERENCE MANUAL
3.4.7 Clearing Jack Installation
Install a new or repaired cylinder, as follows:
1. Push the jack push rod into the cylinder until
the piston bottoms.
2. Attach a sling around the cylinder, and to a
suitable lifting device.
3. Carefully lift the cylinder and position the
cylinder rod up into the frame flange.
4. With the cylinder in place, attach pipe strap
wrench around the jack cylinder head and
turn the jack in a clockwise direction until
the head is tight against the main frame
flange.
5. Tack weld head of clearing jack to main
frame as shown in Figure 3-16.
On the MP800 make sure the cylinder rod
goes through the rod seal, located between
the flanges of the adjustment ring and main
frame. This seal prevents dirt from
accumulating around the cylinder rod and
main frame. Accumulation of dust and dirt
in this area could cause premature piston
seal failure.
6. Connect the clearing jack circuit hoses to the
bottom of the cylinder.
7. After the cylinder is installed and all
connections completed, the system must be
bled to remove any entrapped air. The
system is then pressurized and checked for
leaks. Refer to Section 12 for information on
bleeding and checking the system.
3.4.8 Accumulator Replacement
A faulty accumulator, either the nitrogen gas
escaping to atmosphere or a leak in the internal
bladder, is a serious condition that requires
immediate attention (refer to Figure 12-13). In
either instance, the accumulator will completely fill
with oil. Since the gas or pre-charge has escaped or
leaked from the bladder, the tramp release
arrangement will not function properly. Oil which
is normally displaced from the tramp release
cylinder into the accumulators when uncrushable
material or overloads are encountered, cannot
compress the nitrogen gas within the accumulator
bladders, thereby creating excessive forces within
the crusher’s components.
The accumulator gas pressure should be checked
every 200 hours (1 month). If the accumulator gas
pressure is not at its normal pre-charge level,
69 BAR (1000 PSI) or is unable to sustain the
recommended level of normal operating pressure,
the accumulator should be removed and replaced.
Replace a faulty accumulator as follows:
WARNING
Prior to performing maintenance work on
any part of the Crusher, lockout and tag all
electrical power supplied to the power unit
and Crusher and release stored pressure in
all hydraulic circuits. Death or serious injury
may result if the Crusher systems are
activated while maintenance work is being
performed. Turn the POWER OFF/ON
switch located on the local control station to
the OFF position and lock out and tag the
power supply to the power unit and Crusher.
Depressurize the hydraulic circuits by
opening (turn counter-clockwise) the needle
valves located at the hydraulic power unit
cabinet. This will vent the pressurized oil in
the hydraulic circuits back to tank.
WARNING
Do not attempt to disconnect any of the
hydraulic connections without first insuring
that the system has been depressurized.
Disconnecting a hose while under high
pressure is dangerous due to the high
velocity of the escaping oil and due to the
possibility of being struck by the free end of
a whipping hose.
WARNING
Releasing stored pressure in the hydraulic
circuits does not relieve the gas pre-charge
pressure held in the accumulators. Death or
serious injury may result from a sudden and
explosive release of pressure. Follow all
maintenance procedures when servicing
accumulators.