Culvert making balloon, also called inflatable rubber core mold or inflatable rubber framework, which is to form cavities for large reinforced concrete structures including bridge, tunnels, roof, stake, roof board column, beam, building construction, irrigation works and water conservancy projects, etc. In this way, 20% weight of building structure is reduced than those with solid concrete structures. Meanwhile, inflatable rubber culvert balloon shorten the pipe foundation, increase span as well as provide a simpler and safer construction.
Inflatable rubber culvert balloon can be divided into many kinds according to its shape: round, rectangle, octagon, hexagon, trapezoidal and so on. And round inflatable culvert balloon and octagonal inflatable rubber culvert balloon are common used in most projects.