Instert Heavy Oil Pump is a large channel tubular type oil extraction pump used for heavy oil recovery. There are two different diameter pump barrels and plungers connected in series, with the small diameter plunger and pump barrel at the upper part and the large diameter plunger and pump barrel at the lower part. The upper pump barrel is fixed with an inserted mechanical support anchor, and the bottom plunger of the pump can be connected to a weight rod. When the pump is running on the down stroke, the upper plunger bears the liquid load inside the oil pipe. This liquid load, along with the weight of the weighting rod, helps the sucker rod overcome the resistance of heavy oil and prevent the sucker rod column from bending. The pump does not have a fixed valve, and both the inlet and outlet valves are installed on the plunger assembly. When starting and stopping the pump, the upper pump barrel, inlet valve, and outlet valve are installed together with the plunger. When the lower stroke is blocked, the pump sucks in crude oil, and when the upper stroke is blocked, the crude oil is discharged. The larger valve in the lower part is the inlet valve, which has low inlet resistance. This pump is suitable for heavy oil wells and deviated wells.