Rice Lake Weigh Modules/Mount Assemblies - Manual (Page 35)

WEIGH MODULES
2-6
Single-Ended Beams
SURVIVOR ® 1855HE Modules
These modules use single-ended beam load cells in center-pivoted
modules with capacities up to 10,000 lb per module. Load cells are
NTEP-certified, 1:5000 divisions Class III load cells for up to 0.02%
total error. While these are compression-style modules, the cell is
actually mounted in tension since the load is introduced through
a center loading bolt in a hanging trunnion suspended beneath the
load cell. The trunnion can pivot in all directions on a set of
spherical washers, allowing the top plate (attached to the vessel) to
rock without twisting the load cell. This arrangement makes the
modules self-centering, and able to accommodate movement in all
directions. This module is self-checking and provides lift-off pro-
tection.
The 1855HE modules allow the installer to adjust overall height
easily with the center loading bolt that is attached to the hanging
trunnion. This adjustment feature speeds the process of equalizing
the load between all modules. These modules allow load cell
removal and replacement without raising the tank—an important
consideration in some installations.
Allowable Movement
Figure 2-9 illustrates the 1855HE module with arrows indicating
allowable movement.
Figure 2-9: SURVIVOR 1855HE
Figure 2-10: SURVIVOR RL1800 Modules on
Horizontal Cylindrical Tank
Loading
Bolt
Construction and Features
1) A base plate and spacer support the load cell.
2) A trunnion block is suspended below the free end of the cell
and is attached to the cell using a bolt in tension which is
screwed into a threaded load hole. A spherical washer set is
placed between the bolt head and block.
3) A chair arrangement is attached to the trunnion block through
pivot screws, and the load is applied to the top plate of this
chair. This arrangement allows the chair to move in the
directions indicated in Figure 2-9.
4) Because the load is suspended from the underside of the cell,
the module is self-centering; that is, after a disturbance
temporarily moves the top plate laterally, it will tend to return
to its original position under the influence of gravity.
5) The module provides lift-off protection and lateral restraint.
6) The module provides height adjustment.
7) Hermetically-sealed stainless steel load cells are guaranteed
against moisture damage.
8) The 1855HE module is available in capacities from 1000 lb-
10,000 lb in stainless steel
9) A Teflon ® -jacketed cable and integral conduit adapter heighten
chemical and moisture resistance.
Typical Installation
Teflon is a registered trademark of E.I. Dupont