The oval-shaped inflatable mandrel into the mold: 

 The oval-shaped inflatable mandrel into the mold to be in the ground interview inflatable to check oval inflatable mandrel during the last construction is damaged, leakage, ensure that the mold intact pulled into the hollow plate girder, in order to avoid pouring the process of concrete caused by hidden quality problems. Hollow plate beam within the mold should be in the penetration of the longitudinal interface of the jacket should be facing upwards, in order to reduce the friction of the pull jacket with concrete. In the bottom of the plate girder concrete pouring is completed, the mandrel by rope traction penetrate reinforced cage. Mandrel It hoist traction, fixed pulley-oriented. Bundled hollow plate beam internal model shall be white coir rope, shall not use the rope direct contact with the hollow plate beam mode, in order to avoid core mold damage. 

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