Three common construction methods for grid bolt balls

The processing of grid bolt balls is quite special. This kind of device is generally only used in the grid structure and is not a popular device. Therefore, when constructing this kind of device, it is necessary to formulate the model and style of the bolt ball according to the size and model of the grid steel rod, and there are three ways to install the bolt ball. Let's take a look together.

1. Production of hollow steel balls and steel pipe rods

In order to ensure the installation and quality of the grid and grid bolt ball processing, all hollow steel ball nodes and steel pipe rods are processed in the factory. The steel ball is processed by fetal membrane, and the raw material is 45 steel. The edge is trimmed by a lathe, and the allowable tolerance for processing is: diameter deviation ±1mm, spherical ellipticity deviation <1mm. The allowable deviation of the length of the steel pipe rod is ±1mm, the end face of the rod must be perpendicular to the rod axis, and the allowable deviation is 0.5% R (R is the steel pipe radius), and the maximum bend of the steel pipe rod shall not be greater than 1/1000 of the rod length.

2. Installation of steel grid

Based on and guided by computer simulation theory, a detailed assembly plan was formulated. According to the characteristics of the engineering structure and the layout of the construction site, set up a scaffolding work platform on the ground, lay wooden boards on the scaffold, and then assemble the grid and grid bolt balls on the scaffolding work platform. The assembly of the grid is carried out by the aerial bulk method. construction. According to the actual situation of the grid structure and the characteristics of left-right symmetry, in order to reduce the accumulation of errors in the assembly project of the grid, the assembly of the overall grid should start from the 8 axis and 9 axis of the starting unit, and the starting unit should be assembled first. The vertical and horizontal axis can be adjusted at any time, and the starting unit grid frame can be unfolded from the center to both sides after the starting unit grid frame is deemed correct. During the assembling process, the rods are hoisted in place by the squeegee, and they are assembled and bolted at the design position.

3. Assembling the starting unit

Directly assemble a single rod and a single node into a grid, and the position of each node during the assembling process should be measured and checked. After the grid frame of the starting unit is installed, the self-check is carried out immediately to ensure that the bolts at all nodes are fastened in place. Carry out positioning electric welding (welding 3 points at each support) to ensure that the grid will not be displaced during the subsequent installation process. Then they are assembled in two directions with the starting unit as the center.