Blind Rivet / Multi Rivet

Good practice in the use of the blind rivet / the advantages of the multi-serrated rivet: In order to guarantee a high performance riveted joint, it is important to pay attention to a few things when using the blind rivet. 1) Make sure that the thickness of the material to be riveted is within the rivet's "clamping range". If the thickness to be crimped is "out of range", the following phenomena will occur:

 

  • Case 1: The thickness to be crimped is greater than the clamping range :

The chuck head may fall off after crimping, making the assembly less strong, less tight and less durable.

 

  • Case 2: The thickness to be crimped is less than the clamping range :

 

The mandrel head will not ensure optimum deformation of the rivet: there will be a "banana" deformation and the assembly will not have the expected strength. There is a risk that the mandrel head will eventually come off.

This phenomenon is largely limited by the use of "multi-serrated" rivets, which have a much greater tightening range than standard rivets and, above all, are much more tolerant when used with little precision. In this second case, it can be seen that the multi-serrated rivet deforms "by stratum", ensuring a correct and durable hold.

2) Make sure that the drilling diameters and positions are in accordance with the rivet installation data. - If the drilling diameter is too large, the mandrel will pass "through" the parts to be crimped, without correctly ensuring the deformation of the body and therefore the crimping.

This will jeopardise the durability and strength of the assembly.

 

Again, the use of multi-set rivets is preferred as they will more easily "fill" the drill hole, ensuring a better crimp.

 

- If the hole is too close to the edge of the material, there is a risk of material tearing and failure of the joint under high shear loads:






3) Contact corrosion :

Ensure that the rivet/support material is well matched to avoid the appearance of an electrolytic couple which could accelerate corrosion and thus deteriorate the assembly prematurely. This phenomenon is called "fretting corrosion". contact corrosion".