Shantui Construction Machinery Co., Ltd. has unveiled the "Ground-Adaptive" blade control system for its new DG220 motor graders. In fine grading operations, the blade often encounters hidden obstacles like tree roots or large rocks. When the blade hits a hard object, the machine's frame typically lifts or bounces, damaging the grade finish and stressing the hydraulic cylinders.
The Ground-Adaptive system uses a "Relief-Logic Cartridge" integrated into the lift cylinder circuit. Traditional systems use simple relief valves that open at a fixed high pressure. The new system uses a "Pressure-Derivative Sensor." It monitors the rate of pressure rise in the lift cylinder. If the pressure spikes rapidly (indicating an impact with a rock), the system instantly opens a "Soft-Release Valve," lowering the blade pressure momentarily to allow the blade to ride over the obstacle without bouncing the machine.
The core engineering innovation is the "Blade Float Assist." In traditional graders, the operator uses the "Float" position on the valve bank. In the new system, the ECU calculates the draft force on the blade. If the draft force is high (indicating hard digging), the system commands the lift cylinders to "Active Float," applying a downward force to keep the blade in the cut. If the draft force drops (loose soil), the system reduces the downward force, preventing the blade from digging too deep. This "semi-automatic" logic allows the operator to maintain a consistent grade without constant manual adjustments, increasing productivity by 25% in rough terrain.
