You need to perform the calculation. In reviewing ASME Section VIII, Div 1 Part UG-43, specifically paragraph (g), regarding tapped holes for studs; the threads shall be engaged based on stud length not less than the larger of
the diameter of the stud d(s), OR
0.75d(s) x (max allowable stress of stud at temperature)/
(max allowable stress value of tapped material at temp)
the thread engagement shall not exceed 1.5 x d(s)