Marine ore sand jet relay conveying equipment and working method

The invention discloses ocean ore sand jet relay conveying equipment and a working method, the ocean ore sand jet relay conveying equipment comprises an outer cylinder, an upper cover, a linear driving mechanism, an inner cylinder, an injection pipe, a lifting pipe, a sand washing assembly, a water pump and a control unit, the upper cover slidably sleeves the top of the outer cylinder, and an ore sand input pipe is arranged on the side wall of the outer cylinder. And the linear driving mechanism is arranged outside the upper part of the outer cylinder and drives the upper cover to lift relative to the outer cylinder. The injection pipe is arranged on the upper portion of the inner cylinder, and a mixing cavity is formed between the injection pipe and the inner cylinder. The sand washing assembly comprises a core pipe, an upper nozzle and a lower nozzle, the upper nozzle and the lower nozzle are arranged at the upper end and the lower end of the core pipe respectively, a negative pressure suction cavity is for