What are the General Types of Space Frame Nodes? What are the Characteristics?

Hollow sphere joint: The advantages of this joint are simple structure and manufacturing, beautiful sphere shape, universality, and can be connected to rods in any direction. The disadvantage is that because the ball joint is made of steel plate of equal thickness, the stress concentration is obvious at the junction with the steel pipe, forming a peak of stress, which makes the sphere force uneven. Because the steel pipe and the ball are orthogonally connected, the weld length is equal to the circumference of the steel pipe. There is no margin, and the welding seam needs to be as strong as the steel pipe, and in most cases, the workpiece cannot be turned over when connecting, resulting in a full-position connection of down, side, and upside welding in a circle of welds. So, the requirements are high, but it is difficult.

bolted-ball space frame

Bolt ball joint: The advantage of this kind of joint is that the manufacturing accuracy is guaranteed by the factory, and the on-site assembly is quick and the construction period is short, which is conducive to the shortening of the house construction cycle; its production cost is higher than that of the hollow spherical joint and the assembly cost is lower. This kind of node can be used to construct temporary facilities for easy disassembly and assembly. The disadvantage is that there are many parts that make up the node, which increases the manufacturing cost. The slotting on the strong bolt is unfavorable to its force, and it is difficult to check whether it is tightened during installation. During installation, special attention should be paid to the sealing and anti-corrosion treatment of the joint surface, especially in the southern areas with high humidity.
Steel plate joint: The advantage of this joint is low manufacturing cost, does not require a lot of machining, and is simple in structure. The disadvantage is that the workload on site is too large. It is suitable for the connection of the two-way truss of the angle steel member, and can also be used for the connection of the quadrangular pyramid truss.

Bearing node: it can be directly supported on the top of the column or on the ring beam or brick wall.