What are the differences between bolted ball grids and welded ball grids?

 There are a number of differences between bolted ball grids and welded ball grids in terms of fabrication, construction and design. The following are specific comparisons:

1. Manufacturing process: The manufacturing of bolted ball net frame is mainly carried out in the factory, using mechanical shot blasting to remove rust, and then spraying paint, plastic spraying or zinc spraying treatment to enhance corrosion resistance. 

The steel pipe and welded seam of welded ball mesh frame can only be descaled manually on site, and then paint or fireproof coating is brushed. For the welded part, it needs to be descaled and brushed at a stage to maintain, which increases the cost of later use and affects the safety of the structure.

2. Construction process: 70% of the workload of bolted ball grid frame is prefabricated in the factory, 30% of the workload is installed at the site, only a wrench is needed to tighten the bolts at the site, which is easy and fast, and can be constructed in 300-500 square meters per day. Welded ball mesh frame needs to be operated on site, including material according to the drawing, work release, angle calculation, positioning spot welding, ring welding, cleaning and testing of welded seams and other steps, construction of 80-150 square meters per day, the steel pipe is all butt-welded, the workload is larger, the construction period is slower.

 

3. Project cost: Although the amount of steel used in bolted ball mesh frame is slightly higher, but due to the factory production, only small tools are needed at the construction site, and scaffolding platform is not needed, which can be assembled and greatly save the cost. Welded ball mesh frame itself is lower material costs, but the site construction volume is larger, more welding equipment, higher electricity costs, more welders, scaffolding construction platform occupies a long time, the overall lifting costs, so the project cost is higher than expected.

 

4. Spatial effect: The bolt ball is a solid ball, with specifications of Φ80~Φ400, evenly matched with the pipe fittings, harmonized in proportion, reflecting the bright, lively, elegant and modern style. Welded ball is a hollow ball node, i.e., the ball diameter is very large, specifications for Φ160 ~ Φ900, the spatial level of the ball is large and thin, the proportion is out of proportion, it looks bulky, rigid, depressing.

 

In general, bolt ball net frame and welded ball net frame are different in manufacturing, construction and design. Bolted ball net frame has high degree of factory production, easy construction, cost saving and good space effect. Welded ball mesh frame is mainly made on site, the construction personnel welding technology has high requirements, construction period is long and high cost, generally mainly applied to large span and large load with special requirements of the structure.