1. Design Drawing Breakdown
A complete set of drawings for bolted spherical joint space frames includes design specifications, space frame plan view, layout drawings for top chords, bottom chords and web members, support and bracket detail drawings, material schedules for steel members, bolt spheres, bolts, sleeves, set screws, end plates and conical heads, plus manufacturing detail drawings of bolt spheres.
First, cross-check the space frame plan against the foundation layout drawing to ensure the space frame supports align with building foundations. Next, verify the member material schedule: check the axis length of each grid, then calculate the welded length of members based on axis dimensions, followed by the blanking length of steel tubes. Once all checks pass, generate workshop blanking schedules for steel members according to the member material list.
2. Member Length Calculation
The member length of bolted spherical space frames is controlled by bolt sphere diameter, bolt sphere cutting allowance, sleeve length and conical head dimension.
Member blanking length = Member welded length − 2 × (Conical head length − Conical head stop shoulder length − 1 milímetros)
(The 1 mm value represents the clearance between steel tube and conical head to guarantee welding quality.)
Member post-weld length = Member geometric length − (Radius of one bolt sphere + Radius of the other bolt sphere + Length of one sleeve + Length of the other sleeve) + Cutting allowance of both bolt spheres.
The geometric centre length of members, welded length, blanking length, conical head length, conical head stop shoulder length, sleeve length, bolt sphere cutting allowance, welding gap and component assembly details are illustrated in the attached drawing.
