Pneumatic rubber mandrel (Inflatable formwork) is a kind of cylinder bag that can expand, and shrink. It is easy to use, convenient and durable, it can fold and curl for easy storage when it isn’t inflate, it has the enough strength to withstand the pressure of concrete when it is inflated, and is comparable with any traditional template. It is used in reinforced concrete members, including stake, roof, roof board column, beam, building, water conservancy project (shipyards, slipway, dock) Construction practice proves that Inflatable rubber mandrel is simple to use, save materials, and can be manufactured in several shapes such as round, oval, rectangle, vaulted, trapezoidal pipeline, etc.