Increased Body Capacities
The 770 body capacity at 32.8 yd3 (25.1 m3), has increased 3.5 percent over the 769 at 31.7 yd3 (24.2 m3). Payloads are based on 2,800 lbs per LCY (1660 kg per lcm) material.
Electronic Hoist Control
Provides the operator with better control of the load when dumping, including over-center load control and modulated control throughout the operating range. The automatic body snubbing feature reduces impact on the frame, hoist cylinders and operator.
Fast Hoist Cycle Times
Two stage hoist cylinders provide fast dump cycle times of 9.5 seconds for raise and 12.5 seconds for lower.
Body Design
The new dual slope and flat floor body systems will continue to use fully fabricated, mild steel structures, offering a strong, yet weldable underbody structure. All interior, steel body surfaces that come in contact with material are fabricated from 400 BHN steel to provide superior wear characteristics and resistance to impact. Wide box-section ribs provide excellent durability and impact support in the floor, front-wall, sidewall, and top rail areas. Full-length stringer rails enhance strength and rigidity throughout the body. Other new features that further enhance durability of the understructure include:
- Sidewall ribs are integrated into the floor ribs, forming a belt to provide increased strength in the sidewalls.
- Underbody ribs are increased from seven to nine, enhancing the underbody structural support.
- Front wall body rest supports are integrated into the front wall structure for enhanced durability.
- Full-length, single-piece stringer rails are used, improving the structural support in the body, especially in the body pivot support area.
- Front wall is 400 BHN and the thickness is increased from 10.2 mm (0.4 in) to 16.0 mm (0.63 in), eliminating the need for additional liners for impact resistance in most applications.
Application Specific Body Systems
With the introduction of the next generation of trucks, Caterpillar will build on the previous strengths and provide differentiation through six different body systems. Both dual slope and flat floor bodies will be available in the following configurations:
- Low Impact, Steel Body System
- Medium Impact, Steel Body System
- High Impact, Steel Body System
- Heavy Duty Impact, Steel Body System
- High Impact, Rubber Body System
- Heavy Duty High Impact, Rubber Body System
Steel-Lined Body System
The traditional steel-lined system is well understood by users worldwide. In the new 770 steel body system, the unique design allows the floor and liner to work together to provide the impact and wear resistance. The Medium Impact, Steel Body System offers optimum combinations of wear and impact resistance, while maximizing performance. If the application dictates higher impact or wear needs, the High Impact, Steel Body System or the Heavy Duty, High Impact, Steel Body System provides more impact and wear resistance, but at an increase in body weight versus the Medium Impact, Steel Body System.
Rubber-Lined Body System
A new offering available from the factory is the rubber-lined body system. For impact resistance in hard-rock applications, rubber liners offer a practical, durable and cost-effective solution. They dissipate impact energy, maximizing body life and reduce noise, improving job site work conditions inside and outside the cab. These maintenance-free liners also require minimal installation time. The density of rubber is 20 percent of the density of steel, yet its ability to absorb impact is three times that of steel. This gives rubber a high impact strength-to-weight ratio. In addition, truck operators enjoy a better operator environment, without the hard impacts felt during loading.
Body System Selection
Two primary factors affect body selection:
• Impact
Impact is the energy that is created by the material when it hits the truck body. The condition and size of material, combined with the height at which it is dropped, greatly determines the impact energy that the body must absorb. The most measurable effect of impact is structural bending, chipping, cracking, and spalling. These conditions can be created when the impact absorption capability is exceeded by the impact of the material itself. Generally speaking, a high impact material might be basalt or granite. A medium impact material might be mixture of decomposed rock (75 percent rock, 25 percent dirt), while a low impact material might simply be dry, packed dirt.
• Abrasion or Wear
The tendency of a material to grind away the surface of a body by means of friction is abrasion. Abrasion occurs when a material's hardness is higher than the wear surface that it slides on. A high abrasion material could be any rock material containing a high proportion of hard, angular minerals such as quartz. Granite tends to be highly abrasive. A moderate abrasion material might contain a high proportion of minerals such as calcite. Limestone is most likely in the moderately abrasive category. A low abrasion material could be any material that contains minerals such as talc.
Exhaust Routing
There are three exhaust routing systems available for the 770, depending on the customer's requirements for body heat and sound:
• Full-Time Body Routing
The standard design provides full-time routing of exhaust into the body to heat areas where material gathers. This plays a crucial role in preventing material from being retained in the body during dumping. Not for use with rubber liner body systems.
• Full-Time Muffler Routing
The second option is the full-time routing of exhaust through a muffler, which eliminates exhaust in the body. This option should be used for rubber-lined bodies or applications that do not require body heat.
• Diverter Box Routing
The final option provides a diverter box so that the customer has the flexibility to choose whether to route the exhaust through the body or directly to the outside. Both options go through the muffler. Not for use with rubber liner body systems.
Target Payload Strategy
Your Caterpillar Dealer can help you manage to target payload to maximize equipment use, ensure safe operation, increase productivity and lower cost-per-ton.
- Underloading increases costs due to lost payloads, underutilizes equipment, and increases cost-per-ton.
- Overloading causes excessive wear on vehicle components, such as brakes, tires and drive train, reducing component life and increasing maintenance costs and repairs.
Matched Systems
Designed to work as an optimum pass/match system, the 770 is best sized to match the 988H Wheel Loader, with a 4 pass/match, the 990H Wheel Loader, with 3 pass/match, and the 385C Hydraulic Excavator with a 6 pass/match.