Bobcat recently upgraded the hydraulic system of many of its mid-size excavators to boost performance, controllability, and efficiency. Improvements include a loadsensing pump with torque limiting, smaller cylinders, higher operating pressure, and a new closed-center directional control valve.
Upgraded with the latest in hydraulic pumps, control valves, and cylinders, mid-size Bobcat excavators offer hydraulic advantages over previous models and competitive brands.The advanced hydraulic system, now standard on Bobcat 331 series and 430 excavators, is similar to that used in large excavators. It offers owners and operators several benefits, ranging from smoother, more precise control to more efficient use of engine power.
The excavator's hydraulic system now uses a variable-displacement, axial-piston pump with dual outlet and load-sensing and torque-limiting features. Load sensing enables the pump to respond to changes in load, which prevents bogging down the engine, improves fuel economy, and extends component life.
Smoother operation is provided by a closed-center directional control valve that manages oil flow for seamless multi-function operation as speeds and loads change. This feature produces a consistent, predictable response when a control is actuated.
Smaller bore cylinders, combined with higher operating pressure, improve lifting functions by reducing overall flow requirements. The smaller cylinders also make more efficient use of engine power.
Finally, a pilot-operated travel control system requires less effort to operate and makes machine control smoother, with more predictable response. As with older models, travel can be controlled through a pair of pedals, or hand levers.