Do not mixing the use of steel tubes of diameters of 48mm and 51mm. The putlog couplers on adjacent standing tubes shall be stagger settled, and the connecting heads on adjacent standing tubes shall not be set in the same lift. For the adjacent tube heads every one standing tubes, the splitting placement distance on the height shall not be less than 500mm. And the distance from the tube head center to the main joints shall not be bigger than 1/3.
When starting the erection of standing scaffolding tubes, there shall also be set an prop every 6 spans and can be dismantled until the tie members are sturdily installed and fastened to the main building body.
When the erection height reaches to the structures of tie members, when all the standing tubes including the stainless steel square tube, longitudinal tubes and the transverse tubes are erected, the tie members shall be added into immediately close to the main tube joints and the deviation distance to the main joints shall be no more than 300mm. And the intermediate space to the building body shall be: when the scaffolding height is less than 50m, the longitudinal space shall be 3 meters and the transverse space shall be 300mm.