JUNTTAN PM 20L - Testing Releasing Valves of Forward Inclination Cylinder

JUNTTAN Daily operation section
61
6.4.1.2 TESTING RELEASING VALVES OF FORWARD INCLINATION
CYLINDER
• The forward inclination cylinder is released during leader lifting and lowering.
• If there is any rubbish in the releasing valves it is possible that valves do not
hold the load.
• The valves must be tested every time when lifting the leader to working
position.
Test method:
1) Leader lift device fully up
• Lift the leader up about 5-10 cm from the leader lift device with the forward
inclination cylinder.
• Stop the leader lifting and check out that leader do not sink down against the
leader lift device.
• If the leader stays its place everything is OK and the valve Y5A is closed.
o You can continue leader lifting.
• If the leader sinks down against the leader lift device.
o Lower the leader to transport position and repair the valve Y5A.
2) Leader in vertical position
• Leader in vertical position (see inclinometer).
• Lower the equipment (rotary head/hammer) and the leader foot near ground.
• Check out that the leader do not sink forward.
• If the leader stays its place everything is OK and the valve Y5B is closed.
o Go to the next test (leader inclined 5º forward).
• If the leader sinks forward stop sinking by pulling backwards forward
inclination cylinder lever.
o Lower the leader to transport position and repair the valve Y5B.
3) Leader inclined 5º forward
• The equipment (rotary head/hammer) and the leader foot near ground.
• Incline leader forward about 5º (see inclinometer).
• Stop leader inclining and check out that leader do not sink forward.
• If the leader stays its place everything is OK and the valve Y5B is closed.
o You can start normal working.
• If the leader sinks forward stop sinking by pulling backwards forward
inclination cylinder lever and if necessary lower the leader foot against ground.
o Lower the leader to transport position and repair the valve Y5B.