Fairbanks Tundra Series Truck Scale - Manual (Page 25)

Section 4: Scale Installation
12/12 25 51193 Revision 5
4.3. WEIGHBRIDGE SECTION ASSEMBLY CONTINUED
9. Coat checking bolts with "anti-seize" compound.
4.3.1. Proper Bolt Torque
Tightening bolts to the proper torque is extremely important to the scale’s strength
and durability. Listed below describes how to determine torque level for the different
rigidity of bolts.
The screw’s strength and hardness is Identifying by markings on its head.
U.S. GRADE
of BOLTS
2 5 7 8
SOCKET
HEAD CAP
SCREW
I.D. MARKS
No markings 3 lines 5 lines 6 lines Allen head
MATERIAL
Low Carbon Medium-
carbon
tempered
Medium-
carbon,
quenched &
tempered
Medium-
carbon,
quenched &
tempered
High-carbon,
quenched &
tempered
TENSILE
STRENGTH
(MINIMUM)
74, 000 psi 120,000 psi 133,000 psi 150,000 psi 160,000 psi
Various factors reduce the force needed to get the torque amount.
LUBRICANT OR PLATING TORQUE CHANGES
Oil
Reduce torque 15 to 25%
Dry Film (Teflon or Moly-based) Reduce torque 50%
Dry Wax (Cetyl Alcohol)
Reduce torque 50%
Chrome Plating
No change
Cadmium Plating
Reduce torque 25%
Zinc Plating
Reduce torque 15%