Questions
Answers
Are aluminium rivets resistant to high temperatures?
As temperatures rise, the levels of mechanical resistance of all materials fall off drastically, so the
performance ratings will certainly not be as specified in the catalogue.
For example, aluminium melts at 660°C but already loses 40% of its mechanical resistance at 150°.
Can a rivet be used for non-metallic materials?
Correct positioning can’t be guaranteed. The rivet may draw completely or partly precisely because there is
no resistance to its upward movement, in which case it will cause warping of the parts to be fastened.
We recommend specific rivets for fastening operations of this kind (Multifar or Graf).
Can stainless steel rust?
Stainless steel is highly resistant to corrosion in oxidizing environments.
However, corrosion may occur in reducing environments (in which there is no contact with oxygen).
Does interaction take place during corrosion between the base material and the rivet material?
Corrosion may be marked to varying degrees according to the nature of the materials coming into
contact. It is precisely for this reason that the material of the rivet selected should be endowed with the
same mechanical and physical characteristics as those of the components with which they are to be
assembled.
Galvanic corrosion may take place in the presence of contact between two materials differing in nature.
Rivet material
| Base metal |
Aluminium |
Carbon steel |
Copper |
CuproNickel |
Stainless steel |
| Aluminium |
- |
OK |
OK |
OK |
OK |
| Carbon steel |
NO |
- |
OK |
OK |
OK |
| Copper |
NO |
NO |
- |
OK |
OK |
| CuproNickel |
NO |
NO |
NO |
- |
OK |
| Stainless steel |
NO |
NO |
NO |
OK |
- |
OK = the rivet is protected
NO = the rivet may undergo preferential corrosion
Does the zinc coating conform to the recent directives?
Zinc coating is carried out with Chromium III as set forth in the 2000/53CE, 2000/95CE and 2005/56CE
directives. The coating is white.
However, zinc coating with yellow or black passivation is possible for special needs.
What about the presence of other heavy metals or unauthorized substances?
Our products, rivets and inserts, are constructed with materials which do not contain lead (with the
possible exception of alloys, in which the percentage is authorized), mercury, cadmium, polybrominated
biphenyls (PBB) or polybrominated diphenyl ether (PBDE).
What happens when the holes are larger than specifications?
- The rivet may draw either partly (see Fig. 1) or completely (see Fig. 2)
- The parts may not be fully fastened
- For misaligned holes or holes which are wider or oval, it is best to use specific rivets (Multifar or Tamp).
What happens when you use thicknesses to be fastened which do not conform to specifications?
If greater, retention by the head of the rivet cannot be guaranteed
If less, the rivet may draw or may not fully fasten the parts
What’s the difference between A2 stainless steel and A4 stainless steel?
The basic difference between the two steels is that A4 steel alloy contains molybdenum.
This chemical composition provides optimal resistance to local corrosion (greater than A2 stainless steel
resistance) and therefore enables use in processes bringing this steel into contact with various acids and
chemical reagents even at high temperatures.
This steel is used above all in the pharmaceuticals and food-processing sectors.
Which is the correct nozzle for a blind rivet?
Which technical tests have been carried out on the blind rivets?
Which technical tests have been carried out on the threaded inserts?
Why does the Farbolt rivet draw?
Make sure the riveter nozzle you use is the right one for this product.
Why does the insert thread warp?
This is generally because riveter travel is excessive.
Why doesn’t the insert fasten?
You must adjust inserting machine travel.
Why has the rivet head detached from the bushing?
During assembly it may be that, in order not to warp the bushing by broadening it out, the rivet has not
been fully pushed in.
This does not create problems during the riveting stage because the riveter, through rivet traction, draws
the two components together.
Why is the stainless steel rivet sometimes magnetic?
The material is not truly magnetized. We are dealing with residual magnetism (since stainless steel is a
diamagnetic material) induced by mechanical working (drawing and moulding).
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