Manitowoc Grove RT770E Service Maintenance Manual

BOOM RT770E SERVICE MANUAL
4-2
Published 11/26/2014, Control # 447-05
THEORY OF OPERATION
Boom extension and retraction is accomplished with one
two-stage telescope cylinder, 10 extension cables, and 6
retraction cables. The cylinder rod of the second stage (7,
Figure 4-1) is secured to the rear of the boom base section
and the barrel is secured to the rear of tele 1 by a trunnion;
therefore, extending and retracting the second stage of the
cylinder causes tele 1 to extend and retract, respectively.
The cylinder rod of the first stage (6, Figure 4-1) is secured to
the rear of tele 2 by a trunnion; therefore, extending and
retracting the first stage of the cylinder causes tele 2 to
extend and retract, respectively. The tele 3 extension cables
(qty 6) (8, Figure 4-1) are secured to the rear of tele 2 on one
end, run around the extension sheaves on the front of the
telescope cylinder, and are secured to the rear of tele 3 on
the other end; the tele 4 extension cables (qty 4) (9,
Figure 4-1) are secured to the rear of tele 2 on one end, run
around the extension sheaves on the front of tele 3, and are
secured to the rear of tele 4 on the other end. Tele 3
retraction cables (qty 4) (10, Figure 4-1) are secured to the
front of tele 1, run around the retraction sheaves on the rear
of tele 2, and are secured to the front of tele 3; the tele 4
retraction cables (qty 2) (11, Figure 4-1) are secured to the
front of tele 2, run around the retraction sheaves on the rear
of tele 3, and are secured to the front of tele 4. Therefore,
when the first stage of the telescope cylinder extends and
retracts, tele sections 2, 3, and 4 will extend and retract,
respectively, in a synchronized manner.

Manitowoc Grove RT770E Specifications

General

Brand	Manitowoc
Model	Grove RT770E
Category	Construction Equipment
Language	English