The tensile test shall be carried out on full-size bolts in conformity with the tensile test on machined test pieces
. It is carried out for the purpose of determining the tensile strength. The calculation of the tensile strength,
Rmt is based on the nominal stress area AS ,nom :

AS ,nom= (π/4)*((d2+d3)/2)2


d2 is the basic pitch diameter of the thread (see ISO 724);
d3 is the minor diameter of the thread


in which
is the basic minor diameter (see ISO 724);
H is the height of the fundamental triangle of the thread (see ISO 68-1).
For testing of full-size bolts, screws and studs the loads given in tables 6 to 9 shall be applied.

When carrying out the test, a minimum free threaded length equal to one diameter (1d) shall be subjected to the
tensile load. In order to meet the requirements of this test, the fracture shall occur in the shank or the free threaded
length of the bolt and not at the junction of the head and the shank.
The speed of testing, as detemined with a free-running cross-head, shall not exceed 25 mm/min. The grips of the
testing machine should be self-aligning to avoid side thrust on the test piece.

Tags: Tensile Test