Rivet

History

The rivet is, like part of assembly, contemporary of the work of metals. Derived from the manufacture of the nails, they were then manufactured one by one, the Forgeron.

One later designed machines to manufacture the rivets. These machines of " cold striking " deal with wire whose section is that one wants to allot to the rivet. The free part of the wire is drawn by the machine which it " frappe" to obtain the head which will have an adequate form with its future use (round head, punt, milled, etc); the machine divides the wire so that the rivet has the desired length. It is then the turn of the following rivet.

The Workshops of the Haute-Garonne, rested by Marcellin Jules Charles Auriol (1874-1953) currently became the first world company for the manufacture and the sale of the rivets. Marcellin Auriol, after his Tour de France as blacksmith Companion of the Duty, was established as craftsman blacksmith with In Gélis (Saint-Germier, hamlet of the commune of Teyssode, Tarn). He became then contractor of beatings in the Tarn and finally industrialist with Toulouse (16-18 Rue Notre-Dame).

The assembly of the rivet was initially carried out hot: the rivet sufficiently heated to become easily deformable, is set up and beaten. Its cooling will take part in the work-holding assembled. To avoid the heating, the rivet can be out of deformable metal with hammering. But this mode of assembly requires the access to the two assembly surfaces.

Types of rivet

Standard rivet

It is the traditional rivet assembled cold or hot according to its size. It can be out of mild steel, copper, out of aluminum, duralumin or out of alloy with sufficient plasticity. Selected metal depends on the resistance awaited but also of materials to be assembled. Its head can be round, punt or milled (90° or 120°). Its length is adjusted with the thickness of the assembly: too much short the assembly will be impossible and too length, the dimension of the head exceeding of the assembly the fragilisera.
Two great types: full rivets and semi-drilled rivets. The latter underwent an additional stage during manufacture with the creation of a more or less deep cylindrical hole on the opposite part with the head. Setting being done then while turning over the wall on itself by forming a snap. Typical use: folding chairs.

There exist also plastic rivets, riveting being done generally hot practically without pressure.

Double rivet

Certain rivets consist of two parts comprising each one a head, riveting being obtained by engaging the stem of a part in the stem digs other, light conicity allowing wedging the depression. These rivets are generally out of brass or plastic.

Blind rivet

A true revolution in riveting was carried out by the appearance of the rivet plugs (or marque rivet pop déposée) which does not require any more this double access. This rivet consists of a hollow body (tube with flange) out of deformable alloy, and of a stem whose end is reinflated: the nail. The head can be round, milled or broad for better distributing the clamping force. It is posed with a special grip which draws on the stem whose reinflated end penetrates in the body of the rivet to carry out riveting. When blocking is carried out, the stem breaks automatically by leaving the rivet in place. The nail breaks because of a reduction in the diameter realized under its head during its manufacture. This point of rupture is important because the gripping force will depend on the force necessary to the rupture of the nail.

There exist blind rivets whose body is not bored from beginning to end, but only one side. What gives a tight rivet.

In ordinary version this rivet is out of aluminum with steel stem. But there exist also rivets in Titane for aviation or out of plastic with a low behavior mechanical but corrosion resistant. Other matters are possible for the body: copper, stainless steel A2 or A4, cupronickel…
Also possible of the coatings improving the behavior with corrosion or painting.

The standard blind rivets meet standards AFNOR or DIN. The principal diameters are: 2,4 mm - 3,0 mm - 3,2 mm - 4,0 mm - 4,8 mm - 5,0 mm - 6,0 mm and 6,4 Misters
These diameters are resulting from the metric systems and Anglo-Saxon what explains certain proximities of size (e.g.: 3,0 and 3,2 mm).

Rivet with laminates

During the installation, one intercalates a disc on the side beaten to ensure a better distribution of the efforts of the assembly. This type of rivet is in general short and is often used for the assembly of fabrics and fabrics: the assembly is similar to that of the eyelets.

To withdraw the rivet

To withdraw any rivet (aluminum, plastic, copper…) it should be bored with a drill a little smaller than the center (in general of 6 mm for metals), one can also saw the head.

See too

the Eiffel Tower, an architectural example of the use of 2.500.000 rivets.

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