Blind Rivet Pull Through Issue

[Damiano77]

In a 1/8 blind rivet application I am seeing a pull through failure. The mandrel head pulls through the application and normally breaks off once it reaches the bottom of the rivet body. In other cases the mandrel head completely pulls through.

I am measuring the diameter of the hole in the application to be 3.30 mm (recommended is 3.28 - 3.38 mm)

The rivet body is Aluminum and mandrel is coated steel. I do not have any specifics relating to the material hardness of the rivet body or mandrel.

I isolated the equipment as being a problem all together and still seeing the issue.

Any other factors I should consider?

Please see the picture.

 

[CoryPad]

How about grip length? If your combined panel thicknesses are less than the required range, you can "collapse" the rivet body incorrectly, which can cause the mandrel to pull through.

Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[Damiano77]

I am also looking into the grip range as a possible issue. Currently the rivet body is protruding out approx. 5 mm beyond the combined panel thickness(overall joint thickness).

I am requesting samples with the grip size of the body to be 1 - 1.5 mm shorter than current.

Please see the picture.