4438889 Original Excavator Hydraulic Pump Oil Pipe for ZX330

Hitachi original excavator hydraulic pump oil pipe (part number: 4438889) is a critical high-pressure pipeline used to connect hydraulic pumps with main valves or actuators. According to the accessory information, the oil pipe is designed for universal use, and its specifications (M14 * 1.5 threaded horn mouth) make it possible to adapt to the hydraulic systems of various Hitachi ZX series and some EX series excavators, such as the ZX200, ZX210, ZX240, ZX330 and other common models.

This oil pipe is the core channel for transmitting high-pressure oil in the hydraulic system. As an original or high-quality substitute, it is usually made of high-quality seamless steel pipes and treated with thickened white zinc plating, which has excellent corrosion resistance and rust prevention ability. Its key parameters include a length of approximately 28 centimeters, an inner diameter of 6 millimeters, an outer diameter of 8 millimeters, a wall thickness of 1 millimeter, and the ability to withstand blasting pressures up to 10 megapascals (MPa). The pipe joint adopts a standard M14 x 1.5 threaded horn mouth design to ensure a sealed connection with the hydraulic pump outlet or valve block interface.

The core of maintenance for hydraulic pump oil pipes lies in regular inspections, prevention of leaks, and standardized replacement. A visual inspection should be conducted every 250 working hours in daily life, with a focus on checking for wear, indentation, rust on the pipe body caused by vibration and friction, as well as oil leakage at the joints. Due to the long-term exposure of hydraulic oil pipes to high pressure and temperature cycles, fatigue cracks may occur in their metal parts, and rubber seals may age. It is recommended to conduct a systematic inspection of critical high-pressure oil pipes every 2000 hours of operation or annually