The BW Industries' Cold Rolled Overlap joint is used to connect one or two purlins/rails to a rafter/stanchion. It can be used for overlap connections; butt connections; in the middle of double span purlins/rails; and at gable ends. It should not be used for connections to hip rafters for which a separate connection is available.
For simplicity, this help text, and the joint dialogue, will refer only to purlins and rafters, but unless explicitly stated otherwise, these terms should be taken to mean purlins/rails and rafters/stanchions.
Before and after
- Any modification of the selected parts will cause this joint to be updated.
- Most of the data required for this joint is fixed and is stored in a series of data files supplied with Tekla Structures. The joint cannot handle purlins which are not explicitly included in these files, Tekla Structures will give an error message and leave a red joint symbol. Please contact Tekla Structures support for assistance if that occurs.
- Where the standard data is not applicable, then certain items can be modified through the Tekla Structures connection dialogues, (see below), but it is also possible to tailor the data files to individual requirements. Again, assistance will be given by Tekla Structures support.
- Purlin Positioning
- To achieve the correct bolt positions in purlins and cleats etc., purlins will need to be set out correctly in the model before applying the joint. Where two purlins are to be connected, their centre-lines must be co-linear and they must have the same depth. For the overlap connection, the purlins should be set out with alternate rotations (Top then Bottom).
- It is also recommended that purlins are set out to the rafter centre-line, the connection will automatically extend the purlins to form any overlap and any gable overhang can be entered into the relevant connection parameter. The standard offset from the rafter flange should be obtained from the manufacturer's own literature.
- For consistent cleat positions along a run of purlins, the two purlins will clash with each other in the model, and it is recommended that they be excluded from clash checks by using the select filter, e.g. enter PURLIN in the Name field.
Selection order example
- Click middle mouse button