Rice Lake Combination System - Precision Loads On-Board Weighing Systems - Manual (Page 33)

Applications 29
7. Mark the centerline of the hanger before it is removed from the frame.
8. Burn the old hanger off the frame. Take special care not to damage the frame rails with the cutting torch.
9. Clean the underside of the frame on both sides with a grinder until the underside of the frame rail is smooth
and clean.
10. Inspect the area where the load cell bearing plate(s) will be welded and remove any burrs, debris, paint or
undercoating.
11. Mark the centerline of the load cell assembly so the centerline of the load cell is aligned with the centerline
mark of the center equalizer hanger.
4.4.2 Assembly
1. Assemble the load cell and clamp it into place on the frame so the marked centerlines are aligned.
2. Normally equalizer hangers are laterally centered on the trailer frame and while these hangers are typically
4 to 5 inches in width, the load cells are typically 3 inches in width. Center the load cell bearing plate(s) to
the cross dimension of the trailer frame. If in doubt, assemble the load cell and modified hanger, clamp this
assembly to the trailer frame, and adjust the lateral position to align with the equalizer, springs and torque
arm.
3. Once the load cell bearing plate(s) are correctly positioned, centered and clamped, tack weld to the frame.
Re-check alignment before final welding. It is normally recommended that clamps remain in place for final
welding, if possible.
4. For final welding of the bearing plate(s) the load cell must be removed. Attempting to weld bearing plates
with load cells assembled can result in load cell damage and void the warranty.
Note
Note
Stick welding is generally preferred over wire feed for final welding of the bearing plate(s) to the trailer frame.
5. Follow welding procedures in “Welding Specifications” on page 59.
Allow welds to thoroughly cool before assembling load cells and modified hangers.
6. Assemble modified hangers to the load cells. Use a thread locking compound on all bolt threads. Ensure
the bolts used are Grade 8 and are of the correct thread depth.
Generally, the bolt hole depth of the PL9000-50 load cell is 0.875 inch. A 3/4 inch bolt depth into the load
cell is optimum. Bottoming out a longer bolt can create a hazardous operating condition. Use calipers to
measure thread depth of the load cell bolt holes where the hanger attaches, the thickness of the modified
hanger plate being used and thickness of the washer (if applicable) to ensure (1) adequate thread depth into
the load cell is achieved and (2) bolts cannot bottom out in the load cell.
Rice Lake Weighing Systems provides modified hangers using plates with countersunk bolt holes or with
standard through-bolt holes, depending on the hanger model. For hanger plates without countersunk holes,
hardened (F-436) washers must be used with all bolts.
7. Measure new shaft or tube to connect the two center equalizer hangers laterally. Measure 1/4 inch past the
outside of the hanger hole so the shaft or tube can be welded on the outside of the hanger. Solid shaft or a
thick-walled tube is recommended.
8. Weld the shaft or tube in place on both the outside and inside of the hanger.
9. Reassemble equalizer and torque arm to the hanger on each side of the suspension.
10. Paint the hanger assembly and load cell bearing plate(s) with a high quality enamel paint or spray with an
underbody coating material such as 3M #8883 Universal Rubberized Undercoating.