Pneumatic rubber mandrel is a kind of cylinder bag that can expand, shrink, used to form concrete component of cavity。 It is easy to be used, convenient and durable, is soft and can fold, curly, contraction when it isn inflate, it have the enough strength to withstand the pressure of concrete when it is inflated, this is incomparable 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, not only save materials, and has a shape characteristics, it could be round, oval, rectangle, vaulted, trapezoidal pipeline, etc. Also you can make a straight hole, etc, can make a building structure light, thin wall hollow, change the concrete performance have been used rigid characteristic template situation.