To Define a Fastener in Creo Simulation Live
Defining a Fastener
Perform the following steps to create a fastener idealization between two or more flanges:
1. Click 
Fastener from the Connections group on the Simulation Live tab. The Fastener Definition dialog box opens.
Fastener from the Connections group on the Simulation Live tab. The Fastener Definition dialog box opens.2. Select the inner surface of a bolt hole or a bolt hole axis through which you want to create the fastener. The selected surface must be a solid cylindrical surface.
3. Based on the selected bolt hole and references, the the fastener dimensions are automatically calculated and displayed in the dialog box. You can change the values of the following dimensions:
◦ Shank diameter: Ensure that the shank diameter is less than the bolt hole diameter.
◦ Head diameter: Ensure that the bolt head diameter is more than the bolt hole diameter.
◦ Material: Click More and then select a material from the Fastener-Materials folder. Fastener materials must be linear isotropic materials only.
To create multiple fasteners with the same parameters, holding the CTRL key to select multiple bolt holes with the same dimensions.
Select another bolt hole and click Repeat to create another fastener with the same properties.
4. To create a fastener through two flanges that are not touching each other but have coaxial holes select the Create fastener through the separated coaxial holes check box.
5. Click OK to create the fastener. The fastener is visible in the Model Tree under the Fasteners node.
Creating Probes for Fastener Result Quantities
The following fastener result quantities are available. You can create a simulation probe to study these results at different locations on the model:
Result Quantity | Type |
|---|---|
Fastener Axial Stress | Maximum Minimum Average |
Fastener Shear Force Sum | Maximum Minimum Average |
Fastener Shear Force Y | Maximum Minimum Average |
Fastener Shear Force Z | Maximum Minimum Average |
Fastener Torsional Moment | Maximum Minimum Average |
You can use the formulae in the following section to calculate the fastener factor of safety measures.
Calculation of Fastener FoS Measures
To provide design guidance on the strength of bolted connections, ANSYS computes a bolt factor of safety based on AISC section J3 using ASD.2 While there are multiple codes and standards governing bolted connections, AISC ASD is a stress-based approach for connections without slip. Because it is not based on categorizing load types it provides design guidance for a wide range of applications.
To compute the fastener shear factor of safety use the following equation:
Shear FoS =Fnv/frv
where:
Fnv is the shear stress limit for the bolt and frv is the maximum shear stress in the bolt computed by the software. The shear stress limit for the bolt, Fnv is computed from the yield stress limit for the bolt based on the following equation:
Fnv = Fnt/1.66
where Fnt is the yield stress limit for the bolt, and 1.66 comes from the ratio used in table J3.2 of AISC, of the bolt minimum yield stress for tension against yield stress for shear when threads are present, which is the worst case.
To compute the bolt tensile factor of safety, use the following equation:
Tensile FoS=min(F'nt,Fnt)/ft
where F'nt is the modified yield stress limit for bolts in tension and shear and ft is the maximum tensile stress in the bolt computed by the software. The modified yield stress limit, F'nt, is defined in equation J3-3b of the AISC for ASD computations as the minimum of Fnt or
F'nt =1.3 Fnt-2Fnt/Fnv x frv
Where replacing the shear stress limit, Fnv, with the yield stress limit, Fnt, divided by 1.66 as shown above, F'nt resolves to the following equation:
F'nt=1.3 Fnt – 3.33frv