The steel tubes for the floor type scaffolding shall be 48mm in the outside diameter and 3.5mm in the wall thickness. The surface of the steel tubes shall be smooth without any cracks, fissures, scratches or bending. Newly manufactured steel tubes shall be provided with quality safety certificate. The scaffolding frame shall be sampled tested before put into applications. The steel tubes shall be tested for deformation and extension capacities. Only they are approved can they be used.
The steel tubular scaffolding system erected in this project can use the forged couplers, and comply with the “ steel tubular scaffolding coupler standards” JGJ22-85. All the couplers shall be provided by certified manufactures to make sure all the couplers produced without any fissures, air holes, loose or shrinkage or sand holes.
The specification of the couplers shall be matching that of the steel tubes and the fitting surface shall be even and solid; the moving parts shall be flexible and opening distance of the couplers when they are clamping the steel tubes shall be no less than 5mm. When the torsion force of the bolts reaches 70N.M, the couplers shall not be broken.