7826-B, 9-26-03/GA
Page 2 of 4
Manitowoc Cranes, Inc.
Manitowoc, Wisconsin 54220 U.S.A.
888 SERIES 2
Luffing Jib Raising Procedure
Fixed Jib No. 138 On Luffing Jib No. 135 On Boom No. 22EL
Longer boom, luffing jib and fixed jib combinations must be raised and lowered using this method
B. Layout Jack-Knife Method With Fixed Jib Attached
Raising:
Boom, luffing jib and fixed jib are assembled in layout, end to end, position. Raise fixed jib strut and attach pendants and
backstays. Attach fixed jib stop to fixed jib butt and temporarily tie off to fixed jib strut. Boom, luffing jib and fixed jib must
be inline over front of blocked crawlers prior to raising boom and luffing jib. 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 and fixed 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 and Table 3 and Table 4. Tighten luffing jib suspension with luffing jib hoist. Boom and luffing
jib are then raised together using boom hoist while fixed jib point wheel rolls on ground. Continue raising until fixed jib
suspension tightens. Attach fixed jib stop to luffing jib top. Boom, luffing jib and fixed jib are then raised together using
boom hoist until boom reaches desired boom operating angle. Fixed jib radius must be within capacity chart before swinging
over side of machine.
Lowering:
Position boom at 75 degrees with boom and luffing jib and fixed jib inline over front of blocked crawlers prior to lowering
luffing jib. Lower luffing jib until boom to luffing jib angle reaches value specified in Table 3 and Table 4. Lower boom
until fixed jib point wheel contacts ground. Remove fixed jib stop from luffing jib top and temporarily tie off to fixed jib strut.
Lower boom as fixed jib point wheel rolls on ground. Lower boom until luffing jib point wheels contact ground. Continue
to lower boom while luffing jib and fixed jib roll 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!
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