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The new Caterpillar® AP-755 Track-type Asphalt Paver leverages the strength of its predecessor, the Bitelli® BB 781. This innovative paver incorporates the newest Cat technologies, high production capacities and unsurpassed paving quality. Increased travel speed and material transfer speeds, and a smooth, comfortable ride round out its appeal. The AP-755 replaces the BB 781 and competes in its same class, the over 19 000 kg class size.

The AP-755 was designed for high-production paving applications where optimum paving quality is required at an efficient pace – including motorways, highways, airport runways, and large infrastructure projects in developing countries.

High production is assured regardless of material type, as the AP-755 easily handles hot or modified bituminous mix, or aggregate production. Two rubber crawlers provide excellent traction and its undercarriage progressively overcomes surface irregularities, ensuring machine stability and mat smoothness.

The AP-755 employs a 6-cylinder Cat 3126B ATAAC diesel engine that generates 149 kW (202 hp) at 2300 rpm. Its turbocharged air-to-air aftercooling system provides high horsepower with responsiveness, while keeping exhaust temperatures low.

This generates significant improvements to airflow, improving efficiency and at the same time reducing emissions. Its Electronic Control Module (ECM) provides the operator with constant confirmation of engine performance through a multifunctional digital LCD display on the operator’s control console. The Cat 3126B ATAAC engine meets Tier 2 (EPA U.S. standards) and Stage II (European standards) emissions regulations for off-road applications.

A hydrostatic, closed-loop propel system drives the AP-755’s rubber tracks. Its two pumps are infinitely variable and electronically controlled for starting and stopping ramps. Two variable displacement hydrostatic pumps are driven by the diesel engine and drive two fixed displacement motors.

The AP-755’s working speed ranges from 0 to 26 m/min, with travel speed ranging from 0 to 6 km/h. Reliability benefits are the result of the machine’s completely hydrostatic propel system that eliminates linkages, such as gears, transmissions or chains between the engine power takeoff and the drive system. Less mechanical parts mean less chance for mechanical failure. A variety of popular grade and slope control options are available.

The material handling system of the new AP-755 manages an uninterrupted material flow from hopper to screed. The machine’s two hoppers move material independently by means of two hydraulic cylinders.

Two independently-controlled feeding conveyors are proportionally driven by two ultrasonic sensors. And, conveyor rotation can be inverted from either the operator’s console or from the rear screed control boxes.

Two independently-controlled augers spread the conveyed materials to both sides. Augers are reversible, hydraulically adjustable in height, and their rotation speed can be varied automatically to ensure a homogeneous distribution of material in front of and across the length of the screed. This superior material distribution system leads to unsurpassed mat quality.

Operator comfort was high on the list when the AP-755 was designed. As a result, the machine is equipped with a dual operator’s station that includes two seats fitted on a mechanically sliding semi-platforms. Both seats and sliding console are mounted on pivoting pedestals that allow the operator to easily rotate to the left or right for enhanced visibility. An optional folding canopy assures operator comfort and protection from the elements.

Visibility into the hopper is excellent due to the AP-755’s strategic engine mount (forward and low-to-the-frame). And, its high-capacity cooling system draws ambient air through the engine compartment and exhausts it on the right side of the machine – well away from the operator.

The steering wheel assures simplicity of operation through an electronic digital device that adjusts right and left track motion, providing constant speed and direction. Propel speed is independent of steering commands.

This allows the operator to focus on maintaining head of material, truck contact and other important aspects of the paving operation. Comprehensive machine controls are centrally located on the operator’s console. Controls operating tamper, vibration and screed assist are also located to the rear of the machine for ground crew accessibility.

The AP-755’s low transverse engine mount allows for convenient accessibility to the hydraulic pumps. A wide front service panel is hinged and easily accommodates routine filter and traction valves service. Hydraulic motors are fitted outboard and conveyor motors are conveniently positioned under side panel doors for improved accessibility as well.

A 24-volt electrical system employs two 12-volt batteries and a 24-volt, 70-amp alternator. Caterpillar enhanced-life electrical standards increase reliability and are easy to troubleshoot and maintain. Numbered, nylon-braided and wrapped wiring harnesses are routed away from wear areas and are held securely in place.

Three extendable screed combinations have been paired with the new AP-755 – allowing paving material to be laid to the desired width and depth. All screed options provide exceptional initial compaction and unsurpassed mat smoothness matching operator preference or job specification.

Hydraulic screed models AS-3251 and AS-4251 offer either LPG or electric heating systems. The hydraulic model RM 5700 offers LPG heating systems. Screed combinations offer variable frequency tamper and smoothing plate vibration frequencies.

All screed models are equipped with screed assist, an electro-hydraulic device that maintains constant screed pressure on the bituminous mix, independent from the mix bearing capacity and the paving width. In addition, part of the screed weight can be transferred to the tracks of the AP-755, increasing traction.