PRESTRESS metal bellows tube because the appearance of a significant bump double wave, pipe joints for tight embossed type, firm not trip, contact with the scene after pouring concrete bond strength is very strong, with concrete to form a complete The one, enhance the seismic performance of the structure. Heng-licensing PRESTRESS lightweight thin-walled metal bellows, rigidity, not broken, do not leak pulp, fine features, compared with the general solid tablet, it light weight, span, small deflection, no column caps, safety good, and lower total cost, thus increasing the building clearance, increase the use and sale of the area, with the existing ordinary domestic slab structure, solid flat slab, unbonded prestressed concrete floor compared to save steel 5% -7 %, saving 10% -30% of concrete, saving vertical water, electricity, air conditioning, elevators, interior and exterior decoration with 5% -15%, and has the effect of noise insulation, the considerable economic benefits to the owners. Prestressed concrete bridge with metal bellows Uses: used in bridges, multi-storey factories, car parks, office buildings, apartment buildings, stadiums and other large buildings. Prestressed metal bellows product performance: a rigid test: anti-concentrated load 0.75KN or uniform load when 1.5KN, radial deformation ≤0.1d. 2, permeability test: Spam or grout cement ratio of 0.5 for 30 minutes without leaking, leaking slurry. 3, tensile test: axial tension 5KN wall without damage. 4, anti-pull test: buried in concrete pullout design for bolt for bolt design pullout pullout of more than 2.3 times five, bending experiment: When the curvature radius of curvature for the 30d, no leakage , plasma leakage.