BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI - Universitatea ...

Bul. Inst. Polit. Iaşi, t. LVI (LX), f. 2, 2010 217
4M
τ = .
tc
(3) f 2
πdds
The obtained values are within the safety range of the torsional strength and
the shearing strength of the material. Even if as a result of these calculations a
good dimensioning of the coupling will be obtained, to answer a series of
additional issues (the torque asymmetry on the coupling parts, the distribution
of critical sections on each coupling part, etc.) should be further analyzed by
advanced numerical methods.
2. The Structural Analysis of the Sleeve Coupling
with Pins in the same Plane
The main steps of the procedure for structural analysis of sleeve couplings
with cylindrical pins in the same plane using CATIA/Generative Structural
Analysis environment are:
1. Creating the 3D model. Shall be carried out separately the five elements
of the coupling using the Part workbench. The appropriate materials are
assigned to each element. The assembly of the five coupling elements is
carried out using the Assembly workbench, Fig. 2a.
2. Configuring the mesh. Shall be carried out separately for each element,
by changing the characteristic parameters “Size” and “Sag”, Fig. 2b.
3. Applying the restraints. On the free extremity of the driven shaft a
clamp condition must be applied, Fig. 2c.
4. Applying the loads. On the free extremity of the driving shaft an 800
Nm torque around the shaft axis will be applied, Fig. 2d.
5. Applying the conditions for the interaction between the five elements of
the sleeve coupling. First, the interaction condition of General Analysis
Connection type will be applied between the driving shaft and the first
pin, between the first pin and the sleeve coupling, between the sleeve
coupling and the second pin and finally, between the second pin and the
driven shaft. Second, for all the active areas in terms of the torque
transmission the shearing strain condition must be specified by setting
the just property of interaction between the active coupling elements
(Bolt Tightening Connection Property), Fig. 2e.
6. Launching the solver, running the numerical analysis and results
visualization. The von Misses stress will be presented for both the
driving and the driven shafts in Fig. 2f (scale factor 500), for both the
cylindrical pins in Fig. 2g (scale factor 700) and, finally for the sleeve
coupling in Fig. 2h (scale factor 500).