For the 2004 season, the Akrapovic company is introducing a new production technique in its exhaust system manufacturing process. Hydroforming is a process of tube forming using a medium based on a water emulsion with lubricant additives. The introduction of this technology allows the complete realization of technological ideas which have been developed by Akrapovic R&D. One such idea is our patented D-type header tubes, which up to the present have been manufactured using other production processes. Hydroforming is extremely rare in the motorcycle exhaust system industry, and has been used by our competition more as a prototype technique for exhaust system manufacturing.
The procedure
Mastering the hydroforming process requires a high level of knowledge and thorough preparation. After months of studying and testing, we obtained our first results which we could transform into concrete products, used in the composition of our top Racing and Evolution exhaust systems.
The starting point for the process is the precision production of a mold in which the tube is finally formed. The entire hydroforming process is performed in a closed system under high pressure, in which the mold is placed. The preformed tube is placed into the mold, and the medium is forced through it. Preforming the tube is a process of bending and measuring the size of the tube element so that it conforms to the mold.
Setting up the hydroforming process is exceptionally demanding, since the pressure on the materials themselves increases as the pressure of the medium is increased. The maximum forming pressure is 4000 bar, while 1000 bar is normally sufficient for our purposes. The duration of a work cycle is approximately 30 seconds.
The advantages of hydroforming over classical deep drawing are:
(in the case of tube constructions):
- forming of difficult shapes from a single piece of tubing – changing the tube diameter can be performed as needed, at any point, determined by the shape of the mold
- production of precisely defined shapes – with the optimal tube shape the flow of exhaust gases is improved – unnecessary gas vortices are avoided
- fewer component parts
At the moment the hydroforming process is being used in the production of Akrapovic exhaust systems from our ROAD program. At the same time, due to the unlimited possibilities of adaptation of the process, we are also working on systems from our OFFROAD program.
At Akrapovic we have approached this project very seriously, firmly convinced of its technological advantages, since our development and final products are all aimed at a single goal, improving performance. The introduction of this manufacturing process is also based on the principle that this process should be available not only to the narrowest circle of racers, but to all motorcyclists. The use of hydroforming gives added value to Akrapovic exhaust systems, which the users of such new technologies appreciate, since they know how much effort goes into making this type of technology available.
