Improvement measures of low air pressure in driving room of hydraulic excavator

Due to the limitations of existing manufacturing capacity and die conditions, it is impossible to make too much change on the structure of the cab. It can only be improved from the details in light of the problems found during the test process. The highest level in the industry, that is, the driving room pressure 100Pa as the improvement target, mainly from the following 3 aspects of improvement:

(1) the sealing of special-shaped steel pipe. In view of the poor sealing property of the special-shaped steel pipe, the welded steel plate is blocked at the end of the special-shaped steel pipe, and the hoisting hole on the upper part of the cab is blocked by installing a plastic plug.

(2) improved driving side door frame of the sealing chamber. Optimization of seal section shape, filling material and add in the seal around the corner, in order to ensure the sealing effect of the door with the door frame, and strictly control the flatness of the door and the door frame.

(3) improve the seal between the cab skeleton and the skin. The inner leakage of air between the skeleton and the skin is reduced by welding the insulating plate on the skin and filling the sealing material.

(4) improve the sealing between the hydraulic line and the electric harness and the bottom plate. A new hydraulic tube holder is designed and the pilot pipe is fixed to the floor. The pipe clamp adopts a frame and a press plate type structure, and a rubber block with the shape of a guide pipe is filled in the inner part of the guide pipe to play the role of sealing pipelines and through wire holes.

(5) to improve the tightness between air duct and skin. The air filter duct with the cab caused by skin clearance problems in pressing duct, re design the duct fixing structure, namely Z type fixed plate welding in the skin, form a U groove through the bolt will be fixed in the air duct U grooves, thereby avoiding the generation gap between duct and skin.

Carry out prototype test according to the above improvement measures and stress test on the improved cab. Test results show that the pre-set target has been reached.

After the pilot cab is improved, the dust in the cab is obviously reduced and the working environment is greatly improved. For the whole machine, the improvement of the air tightness in the cab can not only reduce the amount of dust entering the cab, but also adopt sound absorption, sound insulation and other noise reduction measures to reduce the basic conditions of cab noise.