Rice Lake Weigh Modules/Mount Assemblies - Manual (Page 62)

VESSEL ATTACHMENTS
3-10
Restraint Systems
Safety Check Rods
Safety check rods are similar to stay rods in that they
may be applied to a vessel in similar fashion as stay
rods. However, they are fitted loosely to the vessel and
may also be applied in a vertical direction.
Safety check rods are left loose so that under normal
operation they do not apply any axial forces to the
weigh vessel. They are not an active part of the weigh
system. The safety check rods shown do add to the tare
weight of the vessel, but this is constant and does not
affect the weighing accuracy. Safety check rods are, as
the name implies, a safety feature intended to restrain
the vessel if and when it is subjected to large external
or internal forces or if there is a mechanical failure in
the vessel’s normal support mechanism.
Horizontal safety check rods should be
used to:
■
Assure the stability of tall slender vessels or
vessels with heavy eccentrically-mounted
equipment.
■ Assure the stability of vessels against wind or
seismic forces or threat from vehicular traffic.
As shown in Figure 3-7 (a), to be most effective, safety
check rods must be fitted at or above the filled vessel’s
center of gravity. Note that stay rods will perform all
these functions and more; however, safety check rods
are less critical to system operation and therefore do
not require the same attention to detail for successful
installation.
(c) (b)
(a)
Figure 3-7
Vertical safety check rods should be used:
■
On all vessels mounted in tension where failure of the normal
suspension means would allow the vessel to fall and cause
injury or damage, see Figure 3-7 (b).
■ In place of horizontal check rods when it is not practical to use
these to ensure the stability of tall slender vessels or those
subjected to wind or seismic forces, see Figure 3-7 (c).
Vertical safety rods must be installed in an oversized hole in the
lower bracket so that they do not interfere in any way with the
vertical movement of the vessel.
For more information, see Calculating Thermal Expansion of
Vessels and Stay Rods in Section 1.