Dapeng Town Industrial Park, Tongshan District, Xuzhou City, Jiangsu Province, China
The bearing steel balls in grid installation are very small, which can easily cause collisions between rods and cause obstructions during installation. In the construction drawings of large grids and special-shaped grids, bolt balls with a diameter of more than 300mm often appear, that is, the bearing steel balls are too large. Due to the influence of many factors such as the market, production processing, and on-site installation, the installation work will eventually be obstructed.
The following methods can be used for adjustment:
(1) Under the condition that the standard allows, the large balls can be replaced or the corresponding rods can be changed to solve the problem.
(2) Under the condition that the standard does not allow, the cone head and rod of one of the collision rods will be laser cut off, and then a thick steel plate 2~4mm thicker than the wall thickness will be imitated and welded on. The opening edge of the cone head and the rod cut off and the thick steel plate for repairing should be welded (with a hand grinding wheel). After repairing, use a brake to level, remove rust and apply two coats of anti-rust treatment paint.
Solution to the uneven weld:
In some projects, the uneven weld between the seamless steel pipe and the cone head (or connecting plate) often occurs. For some large diameter and thick wall pipe rods, several weldings are required to obtain wide and thick welds. For the uneven welds, repair welding is required. The installed grid processing is feasible under the function of its own weight. For the grid with full static load on the roof, it should be properly supported or welded in sections at intervals to prevent the entire cross section of the rod from being in a high temperature state.
Quality problems of cone head processing and welding with seamless steel pipes:
During the welding of grid rods, the coaxiality limit error between the center of the cone head end hole and the center line of the seamless steel pipe often exceeds 0.02mm. This situation will cause the rod to be in a bending or bending state, and will also cause unrounded stress and reduce the bearing capacity.
It is necessary to adjust the axial force of the rod caused by excessive coaxiality error based on the plastic deformation caused by the partial pressure resistance and the cone head base.
