THE RIMS

Steel rims or aluminium rims ? In this last case, hot forged rims or moulded ? In one, two or three parts? The choice depends mainly of the mission, of the vehicle and of the quantities.
As experts, we know to design and to manufacture all the best solutions, mainly hot-forged two parts aluminium rims and stamped steel rims.
One point is obvious about the choice between several rims technologies: To decide is easy when people knows the right and real specifications of using.
Please read informations below, and don't hesitate to contact us for help and advises!

Some points...

Whatever the rims, five main points are important:
a) Which insert will be fitted (to choose between single part rim or two parts bolted rims) ? Inserts for heavy conditions need a two parts bolted rim

b) How the air flow of the CTIS system will cross from the compressor to the tire valve ? Only aluminium rim can be crossed by the air flow. In case of steel rim, it will be necessary to use an external air pipe, fragile point in case of shoot or shock.

C) By the way, single or two parts ?
> In case of single part rim, stamped steel is the right solution because single part alu rim are molded (die casting) and have not shock resistance. > In case of two parts bolted rims, obviously best solution is hot forged aluminium rim. Material and process offer the best performances.

D) About the cost: Aluminium is more expansive than steel, especially for small series. Nevertheless experience says that sometimes looking systematically for the low cost solution is more expansive than the “right” solution.

E-About design, important point is the “offset”. Not about performances but about the possibilities to use the same forging tools for different wheels in case of aluminium rims

1-ALUMINIUM RIMS

Our alu rims join two bolted parts made in hot forged aluminium 6061. Hot forging technology changes the molecular composition. It is similar to the forging of swords and sabres. Forged blocks are pre-machined and machined. The gap is small (0,1mm) and the quality is constant.
Special technical paints and surface treatment are available.

Cost is sometimes expansive for prototypes or small series because it is necessary to create the forging tools (around 100 000€ by rim design) or to machine aluminium full blocks. Nevertheless, considering forging tools can be used for manufacturing around 50 000 rims or more, cost can be very interesting at long time.


Assets of our aluminium rims:

In comparison with steel rims, aluminium two parts rim offers:
- Light weight (40 Kg lighter than steel), authorising more payload
- Best mobility (reduction of G Force) facilitating heavy off-road
- Excellent rigidity, facilitating beadlock function
- No-corrosion
- Integrated air circuit for CTIS flows through the face of the rim, more secure than external air pipe. Our rim-integrated air flow system is patented in all countries. We are only two manufacturers in the world with this asset...

Nota about the ratio weight/cost: Taking in consideration a 15 tons military armoured 4x4, difference between aluminium and steel rim is around 200kg, increasing the payload. This difference correspond for example in 200 litres fuel, meaning maybe 800km of range increasing... The difference of cost is around 6% of the cost of the vehicle, decreasing at 2,8% for a heavy 8x8...

2-STEEL RIMS

Process of manufacturing is deep drawing, stamping and welding of steel sheets. Cost of manufacturing is low: Specific stamping tools are not expensive, life duration of the machine tool is around 60 years. It is efficient for prototypes, small and large series.

Steel rims are an alternative to hot forged aluminium rims in three scenarii:
- Very large diameter and no fast off-road using (Trailers for tanks or missiles carriers, for example).
- Light vehicles in normal conditions or soft off-road
- Low cost systematic concept of the vehicle

Characteristics of the steel rims:

A steel wheel is designed to withstand the increased weight and forces of modified vehicles, for applications such as light armoured vehicles or cash in transit applications.
RFI steel rims offer high load wheels for some of the most popular armoured light vehicles including Toyota Landcruiser (up to 2200kg load rating), Toyota Hilux, Nissan Patrol, Mercedes G Wagon, Mercedes S Class, Audi A8, Ford F550…

In comparison with hot forged aluminium wheels (and not with die casting alloy), characteristics of steel  rims are:

  • Low price
  •  Weight two times more important
  •  Poor rigidity and structurally too large gap, creating beadlocking problems in case of some runflating inserts (in rubber, for example)
  • Impossibility to use the rims itself for CTIS airflow crossing. External pipe is necessary