C7 Engine with ACERT Technology
ACERT Technology incorporates a series of innovations working at the point of combustion to optimize engine performance while providing high reliability and easy servicing.
C7 Engine with ACERT TechnologyThe C7 engine provides a full-rated gross power (SAE J1995) of 149 kW (202 hp) at 2200 rpm with a torque of 783 Nm. Meets European EU Stage IIIA engine emission regulations. The combination of large displacement and high torque allow the AP755 to perform under the toughest conditions.
HEUI™ fuel injection.The hydraulically actuated electronic unit injectors (HEUI) fuel system is unique and combines the technical advancement of an electronic control system with the simplicity of HEUI fuel injection. The HEUI fuel system excels in its ability to control injection pressure over the entire engine operating speed range. These features allow the C7 engine to have complete control over injection timing, duration and pressure.
Multiple injection fuel delivery.Multiple injection fuel delivery involves a high degree of precision. Precisely shaping the combustion cycle lowers combustion chamber temperatures, which generates fewer emissions, optimizes fuel combustion and translates into more work output for your fuel cost.
High cylinder pressures.High cylinder pressures combined with tightly controlled tolerances promote extremely efficient fuel burn, less blow-by and lower emissions. C7 cylinder block. The C7 engine’s cylinder block offers increased tensile strength. It features improved sealing with gaskets to ensure fewer leaks. This new design supports the engine’s higher compression ratios and increases its power density. The incorporation of straight-thread “O” ring connection points reduce the loss of engine oil and fluids.
Sound reduction features.The C7 engine sound reduction features include composite valve covers with a fully isolated base, a steel oil pan and a cast iron front cover. The HEUI™ fuel systems rate-shaping technology also provides control of sound and vibration levels.
Service, maintenance and repair.Easier service, maintenance and repair is accomplished by monitoring key functions and logging critical indicators. Advanced electronic diagnostic capabilities are possible using CAT Electronic Technician.
Turbocharged and Air-To-Air Aftercooling (ATAAC).The turbocharged air-to-air aftercooling system provides high horsepower with increased response time while keeping exhaust temperatures low for long hours of continuous operation. Air-to-air aftercooling keeps air intake temperatures down, maximizing fuel efficiency and minimizing emissions.
ADEM™ A4 electronic control module.The ADEM A4 electronic control module manages fuel delivery, valve timing and airflow to get the most performance per liter of fuel used. The control module provides flexible fuel mapping, allowing the engine to respond quickly to varying application needs. The control module also monitors engine and machine conditions while keeping the engine at peak efficiency.
Cooling system.The high capacity cooling system provides efficient operation in high ambient temperatures. The system promotes operator comfort by drawing ambient air through the engine compartment and exhausting it on the right side of the machine, away from the operator.
Efficient hydrostatic propel system eliminates chains and other mechanical linkages between the engine and final drive components.
Closed-Loop Hydrostatic Propel SystemClosed-loop hydrostatic propel system provides accurate control of propulsion and low-maintenance operation.
Hydrostatic PumpsTwo variable displacement, hydrostatic pumps are driven by the diesel engine and drive two fixed displacement motors. Pumps are infinitely variable and electronically controlled for starting and stopping ramps.
Speed ControlInfinite speed selection within two propel ranges: one in working mode and one in travel mode, to select the best speed range according to operating modes.
Propulsion ControlAn electro-proportional servo-control provides machine starting and stopping (for asphalt supply, etc.) with no pre-set working speed variation.
Mechanical BenefitsBecause the system is completely hydrostatic, there are no mechanical linkages such as gear cases, transmissions or chains between the engine power take-off and the drive system. This results in a significant reduction in mechanical parts and less chance for mechanical failure.
The steel track undercarriage provides optimum weight distribution, tractive effort assuring great performance.
Two Rubber Shoe CrawlersThe track-type asphalt paver provides a reliable, smooth ride. The optimum tension of the tracks is assured by a grease piston with a shock absorbing system.
Bonded Track PadsThe track pads contain a special rubber compound in order to provide long life and optimum traction. Pads are attached with four bolts for easy replacement.
Two-Speed Planetary DriveTwo fixed displacement motors drive two-speed planetary track drive gearboxes in order to provide infinitely variable speed selection.
The dual operator stations provide complete control and optimum visibility from either side of the operating platform.
Dual Operator StationsThe ergonomic dual operator stations incorporate two adjustable suspension seats fitted on mechanically sliding semi-platforms.
Enhanced VisibilityBoth operator seats and console panel are mounted on pivoting pedestals enabling the operator to rotate either to the left or right. The stations can extend beyond the machine frame for optimum visibility when joint matching or while paving other applications where precise control is required. With the engine mounted forward and low in frame, the operator is positioned away from engine heat and exhaust.
Control ConsoleThe sliding operator’s console panel is fully equipped with comprehensive controls allowing the operator to conveniently monitor all machine functions. A multifunctional LCD-display fitted to the console panel provides detailed information regarding the operating parameters of machine and engine. A lockable vandal cover protects console controls.
Canopy OptionTwo optional canopies are available: folding canopy or hydraulic raising canopy. Both canopies provide full width with two side extending wings for optimum comfort and protection. Canopies can be lowered (manually or hydraulically) for easy transportation.
Material Handling System
Precise mix delivery and productivity through an advanced material handling system.
HoppersThe independent movement of the two hoppers is provided by means of two hydraulic cylinders assuring efficient material flow. Wear-resisting steel provides conveyors and hopper bottom plate for long wear life.
Feeding ConveyorsTwo feeding conveyors are independently controlled and proportionally driven by two ultrasonic sensors. Conveyor rotation can also be inverted from either operator’s console panel or from rear screed control boxes. Conveyors have drive chains to maximize the live conveyor area and reduce center line segregation. This design also provides greater ease of servicing the conveyor drive system. In order to control mix delivery, the operator sets a speed rate for each conveyor that will maintain the desired mix level in the left and right auger chambers.
Auger AssemblyTwo independently controlled augers spread the material conveyed to both sides. Auger rotation speed can be varied automatically to ensure a homogeneous distribution of material before the screed. Two ultrasonic wave detectors control proportional auger movement and can be adjusted from the screed control boxes. Conveyors and auger design eliminate voids under chain case to minimize segregation. Augers have outboard mounted motors for easy serviceability.
Optimum ProductivityThe material handling system allows the operator to maintain an uninterrupted flow of material from the hoppers to the screed. The system is responsible for maintaining the proper head of material - the volume of asphalt in front of and across the length of the screed.
Adjustable Height Auger AssemblyAugers are reversible and hydraulically adjustable in height providing benefits to mat quality and better distribution of material in front of the screed. The ability to raise the auger assembly simplifies loading and unloading from a transport vehicle. Also, when working with larger stone mixes, segregation can often be eliminated or minimized by raising the augers to allow mix to flow unrestricted under auger assembly.
Generator System (Optional)
Continuous-duty integrated design ensures peak performance and high reliability.
Industrial, Continuous-Duty GeneratorWorking range from 1250 to 2200 rpm provides high reliability and low sound levels.
Single Control SwitchA single control switch located on the tractor’s operating console activates the generator.
Full PowerThe integrated, tractor-mounted generator provides full power to the electric screed while the engine is operating from 1250 rpm.
Circuit Breaker ProtectionExtend service life and internal electronic voltage regulation system provides consistent power.
Auxiliary Rear Control Panel
The auxiliary rear control panel provides Full control of tamper and vibrators frequencies for easy ground crew usage.
Right-Hand Auxiliary Rear Control PanelMounted on the right rear side of the tractor provides constant and easy control for ground crew usage during paving operations.
Monitoring And AdjustmentTamper and vibrators frequencies, screed assist & counterbalance system and augers group are conveniently controlled on the panel.
Screed AssistAn electro-hydraulic device maintains a constant screed pressure on the bituminous mix, independently from the mix bearing capacity and the paving width. Screed assist and counterbalance system guarantees superior mat quality and flatness regardless of the speed variations and machine stops for material refilling.
Lockable Panel CoverThe lockable vandal cover efficiently protects panel controls.
Electric heated and LPG hydraulic screeds combine the flexibility to match equipment to operator preferences or job requirements.
Screed ChoicesThe AP-755 is available with the AS-3251 screed and the AS-4251 screed both available with variable frequency tamper and vibrators and with LPG and electric heating system. Also available is the RB 5700 hydraulic LPG screed.
AS-3251 ScreedHydraulic power extendible asphalt screed, it paves from 2.50 m to 4.70 m. With solid extensions added to both sides, maximum paving width is 7,50 m.
AS-4251 ScreedDouble width hydraulic power extendible asphalt screed, it paves from 2.55 m to 5.00 m. With solid extensions added to both sides, maximum paving width is 7,80 m.
RB 5700 ScreedHydraulic power extendible asphalt screed, it paves from 3.00 m to 5.70 m. With solid extensions added to both sides, maximum paving width is 9,10 m.
Tamper and VibratorFor all screed models are operated automatically when the asphalt paver advances following a preset ramp. Tamper starting and stopping ramps are adjustable in order to maintain an optimum mat finish even with the AP-755 stopped during material reloading operations. All screeds are equipped with electronic ignition, automatic and independent adjustment of the smoothing plate temperature for central and each mobil plate.
Electric Heating SystemAvailable for AS-3251 screed and AS-4251 screed. The electric heating system features a tractor-mounted generator, replaceable heating elements and operator friendly controls providing an operator-friendly environment. The system is equipped with automatic adjustment of the smoothing plate and tamper bar temperature for central, each mobile plate and bolt-on extensions up to 7.5 m. Rapid screed preheating is obtained at low engine rpm for quiet operation. Heavy-duty, user-friendly screed heating control unit with self-diagnostic control is positioned at the rear of the machine for easy ground crew usage.
Reliability and Serviceability
Reliability and serviceability are integrated into every Caterpillar machine. These important features keep your machine investment profitable.
Large Access Doors and PanelsLarge access doors and panels ensure quick and easy inspection of the main parts. The service doors and panels also provide optimum ground level serviceability and easy access to the hydraulic pumps and external engine components.
Low Transversely Mounted EngineLow transversely mounted engine provides optimum access to the hydraulic pumps mounted to the right side of the engine. The front service panel features a single wide hinged door that provides easy filter and traction valves serviceability.
Propel Pump ServicingThe optimum displacement of the propel pump provide enhanced servicing.
Ergonomic Operator’s StationEquipped with rotating seats and console panel provides optimum comfort, all-around visibility and easy control during machine operations.
Hydraulic Motors ServicingHydraulic motors for augers are fitted outboard for improved accessibility and serviceability. Motors for conveyors are fitted under the side doors promoting easy access for servicing.
Hydraulic Hoses and Electrical Wiring HarnessesCleanly routed and clamped to reduce wear and provide easy service.
Exposed HosesExposed hoses provided with nylon sleeve protection to reduce abrasion.
Vibrator System Hydraulic LinesCat XT hoses provide optimum durability and resistance to damage.
Integrity of The Electrical SystemIntegrity of the electrical system is ensured with the use of high-quality components.
The Caterpillar Electrical StandardsEnhance reliability and durability, feature numbered and color-coded wires. Nylon-braided wrap efficiently protects the electrical wires.
Electrical SchematicsDetailing wire numbers, wire colors and component part numbers are located in the electrical schematic technical publication.