Agricultural hydraulic design systems must be energy efficient, easy to operate and maintain, and of course reliable.
Designers of hydraulic systems for agricultural machines face some difficult challenges. This is especially true for high horsepower tractors with not only steering and brake functions, but where a great variety of hydraulic implements will be connected and towed. With the operating parameters of a farmer’s collection of cross-branded, specialty implements unknown to a tractor designer, the hydraulic system may be either inefficient due to oversizing and over-design—or it might fail to perform adequately if under-designed.
John Deere Row Crop Tractor, courtesy Deere & Company.
Self-propelled row crop harvesters, as well as fruit and vegetable harvesters now approach the size of many pulling tractors with engines larger than 500 hp. Some forage corn harvesters have engines with more than 1,000 hp. For some of these machines, the only reason to start the engine is to power hydraulic pumps. Others split the mechanical functions between a direct drive gearbox and a hydraulic system. System design must balance the challenge of evenly distributing hydraulic flow to all of the subcircuits while retaining the capability of bringing all of the hydraulic power to bear on motor functions for quick travel between growing areas.
Read the full article by Carl Dyke »