Elliott Digger Derrick, Руководство по эксплуатации и техническому обслуживанию, Страница: 201 / 376

Four Section Boom Operation-common EEC-0021 V1.3
Four Section Boom Operation
Lubrication of the extend cable sheaves located on the boom tip end of the
extend cylinder and the retract cable sheaves located on the inside rear of the 2
nd
and
3
rd
section and the extend cable sheave attached to the bottom of the top plate of the
second section at the sheave case end of the boom are accomplished with the boom
fully retracted. A grease zerk is located on each lubrication point.
Four Section Cable Tensioning
After boom reassembly or from time to time if interior proportioning cables appear loose,
cable tensioning may be required. Tensioning must be done with the boom horizontal
Slightly tighten all cables. Then cycle the boom approx. 4 feet (120cm) out and in a few
times to equalize the extend and retract cable/boom section sequence positioning.
A. Fully retract boom. Do not induce and hold hydraulic pressure. At full retraction,
observing through the winch mount end of the boom, the second section should
be bottomed on the extend cylinder butt plate, the third section should be
bottomed on the thick vertical side plates welded to the inside of the second
section, the fourth section should be bottomed on the thick vertical side plates
welded to the inside of the third section.
B. It is important to achieve these boom section positions before torqueing. If the
boom sections do not bottom out as specified (boom is out of sequence), adjust
cables to achieve proper section positioning. After proper section position has
been established, a scribe mark on all the sections at the boom tip end to identify
proper sections at the boom tip end to identify proper section position relative to
each other may be helpful during the tensioning process.
C. Torque 4/3/2 retract cables to 7 ft-lb (9.5 N.m). Cable adjustment point is located
at the sheave case end of the boom on the bottom of the 2
nd
section. Use the
flats at the front of the cable ends to keep the cables from turning while torqueing
retainer nuts.