Over Driving of Rivets

[MrHiLok]

Hi,

I have a two layered skin panel. One layer is 0.200” inch thick and the other layer is 0.050” thick.
BACR15FV8KE(*) rivet will be installed in this panel. Head will be on the thicker panel side and tail on the 0.050” thick panel.

Is there is a minimum skin thickness requirement regarding overdriving of the FV rivet? Can the buck tail be over driven to 1.5D or this will damage the 0.050” thickness panel in the process?

Thanking everyone in advance for their response.

 

[A380istoobig]

As per Boeing SRM 51-40-02 Figure 3 and BAC5004-1, there is no minimum sheet thickness for the tail side. From personal experience, provided the 0.050" layer is backed by the 0.200" layer, there will be no damage caused by the bucking.

 

[WKTaylor]

CAUTION.
The thin sheet may circumferentially buckle around he rivet as a result of rivet-shank interference and tail compression stresses.

NOTE.
1/4D KE rivets have very high driving forces and are a pain to set without squeeze tooling.

NOTE.
Cherry recommends minimum blind-side sheet thicknesses and alloy/tempers for its high strength blind rivets... because the bulb formation depends on the yield strength/stiffness of the back-side sheet hole-lip.



Regards, Wil Taylor

Trust - But Verify!

We believe to be true what we prefer to be true.

For those who believe, no proof is required; for those who cannot believe, no proof is possible.

 

[jd750ace]

I am making an argument on a current project for the same reason. 2 pieces of 7075T6 .050 sheets joined by a 3/16" E rivet, where a DD was originally specified. The DD, properly prepared, will not damage these sheets, but the E rivet in this instance will overwhelm the bearing strength of the sheets while driving those miserable things. Most of the time, this causes the above mentioned condition, at best, or a tipped over shank which damages both sheets, and increases the headache.