Sand-control washing energy-saving and environment-friendly oil-well pump with long plunger

The invention discloses a sand-control washing energy-saving and environment-friendly oil-well pump with a long plunger and relates to the technical field of oil exploitation equipment. The oil-well pump comprises a pump cylinder and a plunger which is arranged in the pump cylinder in a sliding manner, wherein one end of the pump cylinder is fixedly connected with a lower connection pipe; a fixed valve assembly is arranged at the end part of the lower connection pipe; one end of the plunger is arranged in the pump cylinder in a sliding manner, and the other end of the plunger is arranged in the lower connection pipe; a gap is formed between the lower connection pipe and the plunger; the plunger located in the lower connection pipe is also provided with an oil inlet structure; a free valve assembly is also arranged in the pump cylinder; one end of the free valve assembly is connected with the plunger, and the other end of the free valve assembly is connected with a sucker rod through a connection structure; and the pump cylinder is provided with a drain hole in the connection structure. Pipe spraying and environmental pollution are avoided during well washing operation, and the problems that a well site is large in cleaning difficulty and high in cost after well repairing are solved.