Abaqus for CATIA V5 provides two main strategies for modeling the effects of pretensioned bolts in bolt-tightened assemblies. You can use a general analysis connection and either a bolt tightening connection property or a virtual rigid bolt tightening connection property to define the contact surface pairing between the bolt thread and the bolt support tapping. Alternatively, you can create pretensioned bolts in an assembly by defining the bolts as parts of your assembly, meshing them, and assigning material properties and connection methods to them.
“Real” and virtual bolt tightening connection properties
Abaqus for CATIA V5 includes two connection properties that model bolt tightening in an assembly: the bolt tightening connection property models pre-tensioning at the site of a bolt part in your assembly, while the virtual rigid bolt tightening connection property models pre-tensioning without the use of an actual part. Both connection properties enable you to account for the elastic deformability of the bolted interfaces, but only the non-virtual bolt tightening connection properly accounts for the elastic deformation of the bolt as well.
If you use either of these options, Abaqus for CATIA V5 applies pretension forces to the first step in your simulation history. In the second step, Abaqus for CATIA V5 imposes the relative displacement of the bolt nodes as a displacement constraint, and any loads can be applied in that step and in any subsequent steps.
Bolt pretensioning property
The bolt pretensioning property uses geometry as its support, and you can use bolt pretensioning by applying a point load to the property in your assembly. Because it uses geometry, one advantage that bolt pretensioning provides over the two bolt tightening connection properties is that it enables you to model deformation in the bolt.
Another advantage that bolt pretensioning affords is that you can apply it during any step in your analysis. This difference provides more flexibility, for example, you can resolve some overclosures in the first step before applying bolt tightening in the second step; or you can tighten the bolts in your assembly one at a time in separate steps in the analysis.
Both tightening properties are model properties, so CATIA applies them to all analysis cases in the analysis. If you want to account for the effects of bolt pre-tensioning in only one analysis case in the analysis, consider using one of the two bolt tightening connection properties instead.