8248-A
, 2011-10-19
Manitowoc Cranes, Inc.
4/10 Manitowoc, Wisconsin 54220 U.S.A.
999 SERIES 1, 2, 3
Luffing Jib Raising Procedure
Luffing Jib No.135 On Boom No. 82 or 22EL
B. Layout Jack-Knife Method:
(Longer boom and luffing jib combinations must be raised and lowered using this method)
Raising:
Boom and luffing jib are assembled in layout, end-to-end, position. Slowly raise boom until luffing jib stop strut
is just clear of ground. Attach luffing jib stop pendants and unpin luffing jib stop inner strut from retracted
position. Slowly raise boom until luffing jib stop strut is fully extended and pins engaged (approximately 168
degree boom-to-luffing jib angle). Boom is then raised while luffing jib point wheels are allowed to roll on
ground. Tension should be applied to luffing jib hoist to keep luffing jib strut off luffing jib during boom raising.
Boom up until boom-to-luffing jib angle reaches value specified in table below or vertical, whichever occurs first.
Tighten luffing jib suspension with luffing jib hoist. Boom and luffing jib are then raised together using boom
hoist until boom reaches desired boom operating angle. Luffing jib radius must be within capacity chart before
swinging over side of machine when raising over end of blocked crawlers.
Lowering:
Position boom at 75 degrees prior to lowering luffing jib. Lower luffing jib until boom-to-luffing jib angle reaches
value specified in table below. Lower boom until luffing jib point wheels contact ground. If luffing jib is hanging
vertical, raise luffing jib a few degrees forward of vertical. Continue to lower boom while luffing jib rolls along
ground. Keep enough tension on luffing jib hoist to keep luffing jib strut off luffing jib. Stop lowering boom when
luffing jib stop pendants start to go into tension (approximately 168 degree boom-to-luffing jib angle).
Disengage luffing jib stop strut pins and lower boom to retract luffing jib stop inner strut. Pin strut in retracted
position and unpin luffing jib stop pendants. Rotate luffing jib stop struts forward and lower boom and luffing jib
to ground.
REFERENCE
ONLY!
