User manual CATERPILLAR 844H BROCHURE

[. . . ] 844H Wheel Dozer ® Engine Engine Model Gross Power Net Power Operating Specifications Blade Capacities Weights Operating Weight Cat® C27 ACERTTM 512 kW 687 hp 468 kW 627 hp 15. 9-30. 7 m3 70 815 kg 20. 7-40. 2 yd3 156, 120 lb 844H Wheel Dozer A strong power train combined with a heavy-duty front frame provides long life and economical operation. Power Train Cooling System Structures The 844H features a box-section rear frame and four-plate front frame providing strength and stability. Together they provide resistance to dozing shocks and stresses while absorbing shock loads and twisting forces. The Next Generation Modular Radiator EPA Tier 3/EU Stage IIIa compliant and with Air-to-Air Aftercooling System combined with MEUI, ADEMTM IV, has been added to the 844H to help axle-shaft brakes and impeller clutch meet emissions requirements and torque converter with lock-up clutch improve efficiency, serviceability provides smooth consistent shifting and sound levels. 4 Serviceability Large engine doors, rear access stairs and convenient service platform with large doors enhance serviceability on the 844H. [. . . ] The casting for the rear trunnion mount also serves as an engine mount, which provides a load path for the weight and torque of the engine to travel down to the trunnion and then on through to the axle. Other castings used in the engine-end frame include: front trunnion mounts, steering cylinder brackets, articulation stops and lock link. 1 Box-Section Rear Frame. Absorbs shock loads and torsional forces, solidly maintaining alignment for hitch pins and driveline. Provides maximum structural strength to resist twisting loads during dozing applications. Pivot on double-tapered roller bearings and are shaped to direct stress away from the end of the weld, resulting in a smoother transition of stress loads. 4 Spread-Hitch Design. Helps square up the frame and provides more clearance for hydraulic lines. Double tapered roller bearings and hardened pins resist both horizontal and vertical loads to increase life. Are designed to use mushroom and cup-shaped ISO mounts, reducing component vibration and sound levels. The engine mounts directly to the rear cross member, simplifying and improving load transfer structure. 7 Hydraulics Well-balanced hydraulics deliver precise, low-effort control and trouble-free operation. 3 Load Sensing Steering with STICTM Control System. Is a revolutionary system that integrates steering and transmission into a single controller. The variable displacement pump maximizes machine performance by directing power through the steering system only when needed. More efficient use of power results in decreased fuel consumption and higher production. · Simple side-to-side motions of the stick turn the machine right or left offering a 35 degree steering angle in both directions. Center-point frame articulation allows the front and rear wheels to track. Transmission shifting forward, neutral or reverse is controlled by the operator's fingers and gear selection is controlled by the operator's thumb. · XTTM-3 and XTTM-5 Hose. O-ring face seals and large-bore lift and tilt cylinders top off the hydraulic system, delivering the performance and durability owners expect. A variable displacement pump drives the fan's hydraulic motor so that fan speed varies with coolant temperature. The fan draws only the power needed for cooling, reducing fuel consumption and increasing efficiency. 1 Two Separate Hydraulic Systems. Features four positions: raise, hold, lower and float with detente hold on float. Offers operator selected single or dual-tilt and fingertip control for easy operation. Semi-U Blade. Provides increased capacity with the addition of short wings which include only the dozer end bits without sacrificing spreading characteristics of straight blades. · 9 Operator Station Comfort and control -- a top quality operator station helps maximize productivity. 5 1 6 2 4 3 10 Cab Design. Is spacious and incorporates innovations for operator comfort and productivity, including an excellent viewing area, interior sound levels below 75 dB(A), Cat Comfort Series seat, standard coat hook, cup holder, storage bin, sun visor, trainer's seat with lapbelt and intermittent wet-arm wipers. [. . . ] Cat dealers offer a variety of product support agreements and work with customers to develop a plan that best meets specific needs. These plans can cover the entire machine, including attachments, to help protect the customer's investment. Cat dealers use a worldwide computer network to find in-stock parts to minimize machine downtime. You receive the same warranty and reliability as new products at cost savings of 40 to 70 percent. [. . . ]