Wellhead-lifted vertical oil pipe inner wall scraping and washing device, scraping and washing system and scraping and washing method

The invention relates to a scraping and washing device, a scraping and washing system and a scraping and washing method for the inner wall of a vertical oil pipe hoisted at a wellhead. The scraping and washing device comprises a hanging assembly and a wax scraping assembly which are arranged up and down; the suspension assembly comprises a central shaft, and an unlocking mechanism, a crank sliding block mechanism and a pre-pressing elastic piece which are sequentially arranged along the central shaft from top to bottom; the slider-crank mechanism is in an outward stretching state under the action of the elastic force of the pre-pressing elastic piece, so that the scraping and washing device is hung at the top end of the oil pipe; the unlocking mechanism can move downwards along the center shaft under the downward pressing effect so as to drive the crank sliding block mechanism to contract towards the center shaft, and the scraping and washing device can be inserted into the oil pipe. The paraffin scraping ass