3. B modeling#

3.1. Characteristics of modeling#

This modeling illustrates the methodology for tightening a stud by automatically adjusting the value of the relative displacement between the nodes of the nut and the stud. To do this, the macro command MACR_RECAL is used in a master file and the modeling A is used as a slave file.

The function of the target effort to be achieved:

CIBLE = DEFI_FONCTION (

NOM_PARA =' INST ',

NOM_RESU ='DZ',

VALE = (0.0, 0.0,

1.0, F_ RESULT,),

)

The call to the recalibration command:

RECAL = MACR_RECAL (

PARA_OPTI = _F (NOM_PARA =' DEPL_R__ ',

VALE_INI = 0.004, VALE_MIN = 0.004, VALE_MAX = 0.012,),

COURBE = _F (FONC_EXP = CIBLE, NOM_FONC_CALC =' REACF ',

PARA_X =' INST ', PARA_Y ='DZ'),

)

In the slave file the reacf calculation:

REACF = POST_RELEVE_T (

ACTION =_F (INTITULE =' FZ_CEG ',

OPERATION =' EXTRACTION ',

RESULTAT = RESU,

NOM_CHAM =' REAC_NODA ',

RESULTANTE ='DZ',

GROUP_NO ='N_ SCEG ',),

)

3.2. Tested sizes and results#

The realignment carried out makes it possible to determine a value of DEPL_R_ close to \(8.0E-3\mathit{mm}\). This value makes it possible to put the stud under tension with an average stress of \(30\mathit{MPa}\) in its shaft.

The only quantity that can be retrieved in concept MARC_RECAL is the value of the parameter. The test_result is therefore carried out on this value, and it is a non-regression test.

Result

Reference

Reference Value

Tolerance

Resulting force on the nut

non- regression

\(0.0079595\)

\(5.0E-06\)

Note: in the slave file a printout reacf is made. The effort value corresponding to the parameter is \(\mathrm{-}1.69560E+03\) * , which corresponds to the target effort value.