The distinctively-designed circular arc sliding block (having obtained a national patent) makes the stress distributed more evenly, the load carrying capacity stronger, and the adjustment easier. The local rigidity in boom supporting point is good, which has improved the lifting capacity on boom with same thickness and achieved the goal of greater lifting capacity on lighter boom.

The unique manual full proportional control incorporates the advantages of traditional lever control and electric-hydraulic pilot control. It not only reserves the merits of safety & reliability of original control structure and low maintenance cost, but also realizes that the working speed of actuating mechanism is only proportional to the opening degree of control valves rather than affected by the load. Furthermore, it has improved the speed-regulation performance.

The slewing mechanism has the functions of protecting the crane automatically when the crane is overloaded, reducing the impacts, and activating hydraulic brake when the hydraulic control valve is in neutral position as well as free swing. In addition, it can automatically make boom, wire rope and lifted load slew simultaneously, and minimize the sway of boom and load while the crane starts or stops quickly, and accelerates or decelerates slewing.