Packed sand throwing and filling method by tuck net

The invention relates to a method for filling sand in net bag, belonging to the technique that constructing tank in deep water. Wherein, said invention comprises sand bag, net bag and sling device; it is characterized in that: the size of sand bag is 2.8m*2.8m; the net bag is woven by nylon lines whose surface is coated by fishing net sheets and four angles are connected to slings; four slings are connected to three lifting rings, while two slings at one side are connected to one lifting ring, and another two slings are connected to two lifting rings; two lifting hooks are connected to two movable hooks; the loose hook of movable lifting hook is connected to the sling of another hook; when lifting the net bag, two lifting rings of net bag are suspended on the movable lifting hooks, and the mouth of movable lifting hook is closed, the lifting ring of two slings is suspended on another lifting hook, then using lifter to move the sand bag above the throw point, falling the movable lifting hook, to automatically release two lifting rings of movable lifting hook, utile the sand bag is fallen to the throw point.