Piping structure and hydraulic excavators

The present invention discloses a hydraulic excavator and the piping structure, wherein the structure comprises a hydraulic circuit inside the pipe 3 provided at a plurality of boom excavator 1, the fuel tank by an excavator arm of an excavator and a plurality of tubing 3 cylinders 4 and 5 excavator bucket cylinder communicating. Aspect of the present invention by the conduit passage is arranged in the interior of the boom, that the outer steel pipe protection, longer life and thus, prevent the occurrence of line breakage safety fault, and fault lines in the event of breakage of the security when it can be further protected.