HD320-3 is a kind of crawler bulldozer with the advanced world technology.The hexahedron ROPS cab is of good visibility and excellent appearance.The controls on the both sides are easy,convenient and flexible which accord with the man-machine engineering principle.The machine adopts the hydraulic transmission and hydraulic control technology,and is equipped with the famous Cummins engine.The machine is of high reliability, a long service life and low fuel consumption. The driving parts adopt the high quality steel and are of a long service life.The main forced parts adopt the special alloy-steel to increase the intensity greatly.The blade adopts the special wear-resistant steel to increase the wear-resistance doubly.The hydraulic control adopts the servo-mechanism to make the operation be flexible,easy and convenient.The machine is also equipped with the three-stage wrning electronic monitoring system.