thicker mat is produced. When the rear edge of the
To Support Screed for Travel
screed is raised, a thinner mat is produced. (See Figures
1. Short Distance Travel - The screed lift hydraulic
4 and 5) Mat thickness at each end of the screed is
system includes a locking or holding valve which will
controlled independently so that a tapered mat can be laid
maintain any screed elevation established by the operator
in order to level or to super-elevate a roadway.
with a centering of the console switch toggle. The paver
The pull point height adjustment is made prior to the
can travel short distances safely with the screed
paving job start-up when the normal mat thickness for that
hydraulically "held" in the raised position.
job has been established. (A Table of pull point heights
2. Long Distance Travel - Safety cables are provided
recommended for various mat thickness is shown in
for long distance travel. It is recommended that for all
following paragraphs).
It should be noted that a
travel other than short on-the-job paver movement, the
difference in materials used for paving will have a great
safety cables be attached to the support hooks.
affect on all adjustments of pull points and handwheels.
To hook the cables, raise screed to upper limit until
cables can be hooked. Then lower screed until slack can
be observed in both lifting cables.
To Support Screed for Maintenance Work
IMPORTANT! Whenever the screed is to be
worked-on while it is elevated, use the safety
cables to support its weight. Never rely upon
the hydraulic lock feature to keep the screed
elevated when personnel are in the screed area.
Effect of Handwheel Adjustment on Screed
Figure 5
A foot operated lock keeps the handwheel adjustment
fixed. The operator must step on the pedal and release
the lock before the handwheel can be turned. When
released the lock engages automatically.
Each end of the long screed can be adjusted so that
the mat thickness is far from equal when measured at
Making Mat Thickness Adjustment - R.H. Side
each edge. (See Figure 6)
Figure 4
HANDWHEEL GAUGE AND SCALE
MAT THICKNESS CONTROL (MANUAL)
A gauge and scale on each handwheel screw serve as a
The thickness of the material deposit or mat left by the
reference for the operator. The vertical scale, graduated
paver is determined by two factors;
in inches, is fixed to the pull arm. The disc type gauge is
(1) The height of the screed pull points on the tractor
held in place on the handwheel screw by means of a
unit.
setscrew and can be moved up or down, to establish the
(2) The screed angle in relation to the pull arm. The
desired reference. It is marked to show 12 equal divisions
screed angle adjustment, made by turning the
of one complete turn. (See Figure 7)
handwheel at each end of the screed, is the
intended manual control of mat thickness during a
paving run. When the handwheels are turned to force
the rear edge of the screed downward, a
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