High pressure low temperature liquid nitrogen pump hydraulic terminal

The invention discloses a high pressure low temperature liquid nitrogen pump hydraulic terminal, belonging to the oil field liquid nitrogen conveyer device field. The high pressure low temperature pump hydraulic terminal of the invention comprises a plunger piston and a cylinder body; wherein the plunger piston and the cylinder body are sheathed and connected, the cylinder body is provided with an entire valve, a spacer bush is arranged between the cylinder body and the plunger piston, the spacer bush and the entire valve are connected, the outer surface of the spacer bush is provided with a first groove, the end face of the spacer bush far away from the entire valve is opened with a second groove which communicates the first groove and the interior of the spacer bush, the side wall of the cylinder body is provided with a precooling liquid inlet and a precooling liquid outlet, and the precooling liquid inlet and the precooling liquid outlet are respectively communicated with the first groove. The high pressur