Automatic aligning system and aligning method thereof

The invention discloses an automatic aligning system comprising a positioning device and a cap removing and sealing device. The positioning device comprises clamping mechanisms and two retainers; the two retainers are arranged on a conveying passage of a storage tank in a manner of moving vertically; the clamping mechanisms are arranged on two sides of the conveying passage and in directions perpendicular to the conveying direction of the storage tank. The cap removing and sealing device comprises a lifting mechanism and a grab mechanism which are connected with each other, and a positioning sensor group includes a first sensor and a second sensor which are arranged outside the grab mechanism at an interval. The first sensor is used for scanning the storage tank along the first direction and the second sensor is used for scanning the storage tank along the second direction perpendicular to the first direction. The positioning device is used for primary aligning of the storage tank, and the first sensor and the second sensor are used for precise aligning of the storage tank, so that high aligning precision is achieved. The automatic aligning system is simple in structure, convenient to install and easy to maintain, and low in running and maintenance cost. The invention further discloses an aligning method of the automatic aligning system.