The overall structure of small wheeled excavator is basically the same as that of general excavator, and the main differences are turntable, slewing mechanism and walking chassis. The main frame is welded with channel steel, and the sub frame is welded on the main frame, which is used to install the slewing seat and swing oil cylinder, so that the working device can realize 180 ° half rotation. The turning center should be arranged 100 ~ 150 mm in front of the rear axle to improve the walking stability and climbing ability. The steering front axle is elastically connected with the frame, and the driving rear axle is rigidly fixed with the frame. In order to ensure the stability during operation and no-load of tire and axle, two frog legs are installed on the subframe in the middle of the frame, and two eight shaped legs are installed on the back of the frame, which can increase the bearing capacity and make the mechanism easy to arrange. During excavation, the four outriggers are opened, the front and rear tires of the excavator are 200 ~ 250mm above the ground, and the front and rear outriggers can not exceed the width of the chassis after being folded up. The engine is installed in the front of the frame, and the transmission system adopts auto parts. The whole frame and walking mechanism should be simple, economical, practical and easy to manufacture.
Reasonable cost reduction and performance improvement are very important for small wheeled excavators. Due to the limitation of the cost of the whole machine, it is impossible to choose the special parts for construction machinery. In the selection of hydraulic pump, directional valve group, hydraulic cylinder and engine and other accessories, we should consider not only the quality, but also the price, and require a harmonious balance between cost, performance and quality.
The manufacturing method of structural parts of small wheel excavator is also quite different from that of general excavator. By designing the structure of boom, stick, bucket and frame reasonably and adopting unique manufacturing method, the manufacturing cost can be effectively reduced.