Diesel high pressure fuel pipe assembly

The high pressure fuel pipe assembly of the diesel engine is a high pressure pipeline for the high pressure fuel pump to deliver high pressure fuel to the high pressure fuel nozzle. When the diesel engine is in operation, the high pressure fuel pipe assembly is subjected to the heavy impact load of the high pressure fuel and the additional load generated by the vibration of the diesel engine. Therefore, the high pressure fuel pipe assembly connected to the high pressure fuel pump and the high pressure fuel nozzle must have sufficient pressure resistance and the ability to lock, anti-vibrate and prevent leakage.

A high pressure fuel pipe assembly for a diesel engine is composed of a high pressure fuel pipe, a locking sleeve and a coupling nut. The three-dimensional spatial structure of the high pressure fuel pipe at both ends of the left-handed fine external thread is matched with the left-handed fine internal thread of the rigid portion of the locking sleeve. The heads at both ends are a composite surface of a spherical surface and a waist surface, and the spherical surface cooperates with the high pressure fuel pump and the tapered surface of the end of the high pressure fuel nozzle to form a high pressure sealing joint surface; the locking is installed at both ends of the high pressure fuel  pipe. The sleeve is divided into a rigid section which is connected with the left-handed fine thread of the end of the high pressure fuel pipe and an elastic section which is matched with the high pressure fuel pipe, and the outer end surface of the elastic section is a spherical surface; the inner hole of the coupling nut which is set on the high pressure fuel pipe is thinly right-handed the tooth thread and the cone surface are formed, and the right-handed internal thread is coupled with the right-hand external thread of the high pressure fuel pump and the end of the high pressure fuel nozzle, and the tapered hole surface cooperates with the spherical surface of the outer end of the elastic portion of the locking sleeve.

In order to solve the above technical problem, the diesel high pressure fuel pipe assembly of the present invention comprises a tubing body, a sheath, a compression washer and a pipe joint nut, and the end of the tubing pipe body is expanded and formed, and the tubing pipe body is expanded outside the pipe end. A sheath is disposed at the joint of the expanded pipe end and the fuel pipe body; a pipe joint nut is disposed outside the fuel pipe body; and the fuel pipe is integrally formed.

The surfaces of the tubing body, the sheath, the compression washer and the union nut are all galvanized.

After adopting the above structure, since the fuel pipe body is integrally formed and the pipe end of the fuel pipe is provided with a sheath, the fuel pipe body is protected, and the pressure washer and the pipe joint nut make the high pressure fuel pipe connect more firmly and tightly.