How to Test Riveting Nut Mechanical Properties?(Ⅰ)

Test load

Test load is an axially applied load, rivet nut thread should not be flaking or fracture under this load. In terms of the test, test load means a value; while for the application in design, it is a maximum.

In the test, test load loaded to the test nuts by the tested bolt which has done axial load or machine tool spindle. When to unload, it must be free to remove the nut from the bolt or mandrel. This requirement is very interesting, due to it proves the extent thread twisted is not enough to make the engaging threads binding together. Test shows that when the applied load reaches the 95% of the load which is able to flake the nut thread, then they will bond together.

Test load of nuts in most class standards of nuts strength use the term "stress", which means pounds per square inch. When calculate the real test load in pounds, using experimental stress (psi) multiplied by the force area.

It is very important that in addition to the common stress areas, test load is unrelated with those specified externally threaded fasteners . To be continued...