Tubular members and matched connections for three-dimensional roof grids
A space-frame roof depends on the fit of every bar and node. We supply the steel members and connection package against the project grid, with member ends, node orientation and support details kept together through fabrication and packing.
| Tubular members | Diameter, wall, grade, finished length and end arrangement by member mark |
|---|---|
| Nodes and connectors | Joint type, node orientation and mating connection geometry from the approved system detail |
| End components | Specified cones, sleeves, bolts or welded end arrangements, matched to the node system |
| Supports and perimeter | Bearing nodes, seats and edge members included as scheduled items |
| Roof attachments | Purlin stools or other secondary connections at the designed grid positions |
| Protection | The ordered coating or galvanizing route, including thread and mating-surface treatment |
| Packing identity | Member, node and zone marks carried into the parts list |
Where the selected node detail uses ISO metric threads, the pitch is part of the connection identity. These coarse-pitch pairs help distinguish the intended mating thread.
| Thread designation | Nominal diameter (mm) | Coarse pitch (mm) |
|---|---|---|
| M12 | 12 | 1.75 |
| M16 | 16 | 2.00 |
| M20 | 20 | 2.50 |
| M24 | 24 | 3.00 |
| M30 | 30 | 3.50 |
| M36 | 36 | 4.00 |
No matching specification. Clear the search to see every row.
Scroll sideways to see every column.
ISO metric coarse-thread reference, cross-checked in the WDS thread-dimensions table. Node-system drawings set the actual thread, tolerance, engagement and end assembly. These values are thread dimensions only.
Two bars with the same outside diameter can have different walls or grades. The component schedule preserves both, together with the finished member length,, so visually similar bars stay separate items.
A bolted node can use a particular bolt, sleeve and tapered member end. Joint fit and design resistance come from that specified set. We price the complete specified connection set.
The structural design identifies the system and joint behavior. Fabrication records cover the supplied member and connection work, with the adopted material, welding and examination requirements assigned to the relevant parts.
Tube cutting dimensions are derived from the approved finished-member geometry and the connection allowances. End cones or plates are fitted on that basis so the assembled bars meet at the intended node positions.
A node with a different hole angle or support attachment is a different component, even if its outside diameter matches. Node marks identify those geometric differences before the pieces reach the installation zone.
The protection route accounts for coated threads and mating faces. The supplied thread fit follows its specified tolerance and finish, so components arrive matched and assemble without force at site.
Perimeter bars, roof openings and support nodes rarely follow a repeating internal grid without changes. Their end arrangements and local secondary attachments are separated in the bill of material.
Repetition helps organize the steel lot, but edge and support zones still have their own bars and nodes. Each zone is supplied with its required component mix.
Curved or stepped roof geometry produces changing member angles and elevations. Coordinates, member marks and the correct end connections carry that geometry into the fabricated package.
Openings and suspended attachments have defined locations in the grid. Their support details belong in the node or member design, resolved before delivery.
Length checks use the finished-member datum and the specified end components. Diameter, wall and grade stay linked to that member mark so each member is identified by its actual steel section.
The check covers the relevant end fit, thread identity and access to the connection hardware. Any trial-assembled grid module uses the specified members and nodes, not a collection of similar-looking sample parts.
Component marks identify the grid location and mating parts. The final parts list distinguishes repeating bars from special edge, opening and support components.
Long members are supported and bundled with protected ends. Nodes and loose end components are counted separately so the receiving team can reconcile a complete installation zone before assembly.
Our quotation identifies the scheduled bars, nodes, end fittings and support steel. Roof area describes the project size; the component quantities and connection scope are listed separately.
A replacement bar or node retains its original geometry, material and mating-end references. That information matters more than ordering a general tube diameter or ball diameter from a photograph.
The quoted package identifies the fabricated members, nodes and connection parts. Structural design, site erection and temporary stability work are separate responsibilities unless expressly included in the contract; supplying the steel components does not include those services automatically.
The proposed load and attachment location return to the responsible structural designer. The affected bars, nodes and local connections are checked before a revised component schedule is issued. For parts already produced, that revision also identifies the required modification or replacement work.
No. They have different connection geometry, assembly methods and potentially different joint behavior. A change of system belongs in the structural design and component schedule before fabrication.
A replacement fastener must meet the specified joint design, material, thread, engagement and assembly requirements. Ordinary rod with a matching diameter does not establish those properties or the complete end-connection fit.
Yes. The standard coarse pitch is 2 mm, while a common fine pitch is 1.5 mm. Those mating threads are different. The connection schedule retains pitch, tolerance and engagement as well as diameter, so an M16 description alone is not a replacement specification.
No. Material identity and physical fit answer different questions from joint resistance. Where a connection test or system approval is required, its record identifies the relevant joint configuration, test method and acceptance basis. A successful dimensional trial assembly is not reported as a load test.
Other items in the same product category.
We wrote these for buyers specifying and receiving exactly this kind of package.
Share the roof grid, component schedule, joint details and required finish. We will price the bars, connection parts and support steel by the defined supply package.