Door frame welding device convenient to assemble and not prone to loosening

The utility model provides a door frame welding device convenient to assemble and not easy to loosen, which comprises a base, two sliding chutes are arranged in the base, a translation mechanism is arranged above the base, the translation mechanism comprises clamping blocks clamped in the sliding chutes, a sliding plate is fixed above the clamping blocks, and the sliding plate is connected with the sliding chutes. A protection assembly is fixed to the side wall of the sliding plate, a sleeve is fixed to the left side of the sliding plate, a fixing plate is fixed to the upper surface of the base, and an elastic mechanism is installed in the second concave table. According to the highway bridge structure stability detection device, the sliding plate forms a translation structure through the movable rod between the clamping block and the sliding groove and the electric cylinder, the movable rod can be controlled to move in the left-right direction through driving of the electric cylinder, and the movable rod mov