Sequential opening and clamping device

The invention discloses a sequential opening and clamping device which comprises a clamping and supporting block and a clamping block. A welding support is arranged between the clamping and supporting block and the clamping block to be fixed. A through hole is formed in the middle portion of the clamping block. A bolt locating block is arranged in the through hole. The clamping block and the bolt locating block are of two independent structures. The bolt locating block and the clamping block are arranged to be two independent mechanisms, after bolt welding locating is completed, the bolt locating block is firstly pulled out of a bolt (the clamping block keeps still), the clamping block still enables the support to be pressed and attached to the clamping and supporting block at this moment, and the bolt can retreat from the bolt locating block easily. The sequential opening and clamping device is simple in structure and convenient to operate, and the welding quality and efficiency are greatly improved. 本发明公开了种