Grab bucket of portal crane

The utility model provides a portal crane grab bucket which comprises a fixing seat, two jaw plates symmetrically arranged below the fixing seat, a supporting frame hinged to the outer side of the upper end of each jaw plate, a connecting plate fixedly arranged on the inner side of the upper end of each jaw plate, the upper end of each supporting frame hinged to the fixing seat, and a supporting shaft fixedly arranged on each connecting plate. A pulley is rotatably arranged on the supporting shaft, a steel wire rope is sleeved on the pulley, a traction device for tightening or releasing the steel wire rope is arranged on the fixed seat, and jaw plate protection components are detachably and fixedly sleeved on the opposite sides of the two jaw plates; in the material grabbing process, the jaw plate protection assembly is in friction with the ground and the materials, jaw plate abrasion caused by direct contact between the jaw plate and the ground is avoided, when the jaw plate protection assembly is abraded af