3071564 Original Excavator Spare Parts Oil Pipe for EX200-5 EX220-5 EX280-5

Part number 3071564 is labeled as PIPE (Metal Oil/Piping) in Hitachi's original system and belongs to the disassembly diagram of the main hydraulic pump device (HPV102 series pump assembly). It is often referred to as the hydraulic pump device oil pipe/pump body return (or bypass) oil pipe. This item is mainly suitable for medium-sized excavator platforms of the EX/EX-5 generation, with typical models including EX200-5, EX220-5, EX210H-5, EX230-5, EX270-5, etc. (derivative versions such as EX200-5HG, EX200-5X, EX220-5HHE, EX225USR (LC) and other platform variants also share this pump system architecture).

As the original metal piping on the pump device, its main function is to establish a reliable oil passage in the specific oil circuit of the pump body (commonly known as the shell return/drain/bypass oil circuit), safely guide the oil back to the oil tank or into the system return side, and participate in the sealing boundary of the external interface of the pump unit. The original factory pipe body is usually made of cold drawn seamless steel pipe, which undergoes CNC bending → two end pier making/machine joint → stress relief treatment → surface rust prevention (phosphating/coating or plastic coating). The sealing surface of the joint is mostly O-ring groove or metal metal cone surface, and the bending size, pipe end perpendicularity and sealing surface flatness are strictly controlled to prevent micro cracks, leakage and looseness under continuous vibration of the pump unit and system pressure.

Daily visual inspection only: monitor whether there are fresh oil stains or gray lines at the joints of the body and both ends, whether the pipe wall rubs against other parts, and whether the pipe clamp/shock-absorbing adhesive falls off - vibration abrasion through the outer wall often starts from here. There are three key points when disassembling and assembling: ① First, remove the system pressure and clean the sediment around the joint; ② Before dismantling the pipe, take photos and record the pipe path and clamp sequence. When installing a new pipe, let it "naturally sit in place" and never use a lever to forcefully break it into place; ③ Replace all sealing components (O-rings/copper pads/aluminum pads) at both ends and tighten them according to the specified torque (tightening too tightly will cause deformation of the joint neck and leakage, while loosening too loosely will result in vibration loosening).