For slabs when erecting scaffolding system, as the erecting height of four way ring scaffolding system may not be enough to reach transom, there will erect u-head scaffold screw jacks at the top of the scaffolding system to adjust the height of standing tubes in the slab system. And the u-head screw jack, if extruded out of the head, the extruding length shall be less than 20cm.
For the extra extrusion length, take measures and treatments relatively like setting another u-base plate at the bottom of four way ring scaffolding. That is to say, set at both the top and bottom of the scaffolding with a u-screw jack to adjust the entire height of the whole scaffolding system. It shall be guaranteed that extrusion length of the screw jack shall be less than 20cm to keep the shoring systems and u screw jacks stable when working under pressure.
For setting posts, one row of scaffolds can be excluded when erecting to leave space for setting up formwork. Once the formworks has been set up, use steel tubes and crossing couplers to adjust the screw thread of the u-screw jacks and then fix the formworks on the four way ring scaffolds.