Milton CAT 770 - Manual (Page 8)

Box-Section Design. The 770 frame uses
a box-section design, incorporating two
forgings and 13 castings in high-stress
areas with deep penetrating and
continuous wrap-around welds to resist
damage from twisting loads without
adding extra weight.
• Steel Structures. Mild steel used
throughout the frame provides flexibility,
durability and resistance to impact loads,
even in cold climates and allows for easy
field repairs.
• Castings. Castings have large radii with
internal reinforcing ribs to dissipate stress
in areas of high stress concentration.
Castings move welds to lower stress
areas for greater frame life.
Integral Four-Post ROPS Cab.
Resiliently mounted to the main frame
with all-new cab mounts that reduce
vibration and sound, the integral ROPS
is designed as an extension of the truck
frame. The ROPS/FOPS structure
provides “five-sided protection”
for the operator.
Forgings and Castings.
• The 770 features a drop tube/casting
design and two forged steel mountings
for hoist cylinders, similar to the
design as found on the 773.
• A volcano casting that holds the center
tube is enhanced with thicker wall
dimensions for increased durability.
• New strut-mount castings have been
moved 254 mm (10 in) forward and
25.4 mm (1 in) outward on each side.
These thicker strut-mount castings
and their location improve ride
characteristics as well as durability.
• New steering casting (same as 773)
accommodates larger steering
cylinders and ball studs.
• New tail casting accommodates new
angled rail design.
Superior Weld Quality. Structural frame
welds are J-groove type, ensuring full
weld penetration for strength and
longevity. During fabrication, weld
integrity is further enhanced by rotating
the frames 360 degrees to provide
optimal, flat welding surfaces.
Technology Enhanced.
Caterpillar structures are tested using
System Structural Analysis (SSA) to
dynamically simulate operations in field
environments and identify potential
structural improvements in high stress
areas. With analysis of machine structures
and variables, such as haul road and
payload, structural improvements were
made to the frame to accommodate the
new cab, platform, engine and radiator.
Quality Control. A Coordinate
Measuring Machine (CMM) is used to
inspect truck frames for consistency in
the manufacturing process. In addition,
all critical welds receive testing to verify
weld penetration, which results in frame
durability.
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Rugged Cat structures are the backbone of the 770 off-highway truck’s durability.
Structures