Vai al contenuto

Ad Arese l'8 chi c'è?


il FUSI

Messaggi Raccomandati:

  • Risposte 106
  • Creato
  • Ultima Risposta

I più attivi nella discussione

I più attivi nella discussione

Leonardo...

mai

MAI

MAI

dare loro queste soddisfazioni. Non mi stancherò mai di ripeterlo.

Uèèèèèèèèèè MUMENT! Non do loro soddisfazione, semmai gli sto dicendo che mi fanno schifo (e tralascio di fare della polemica, oggettivamente lanciai un campanello abbastanza inascoltato mesi fa!).

firmaboh.jpg

'80 Alfasud 1.2 5m 4p --- '09 147 JTDm Moving

Link al commento
Condividi su altri Social

Leonardo...

mai

MAI

MAI

dare loro queste soddisfazioni. Non mi stancherò mai di ripeterlo.

quoto.

perchè levare le cuoia e dar loro la soddisfazione, sopratutto quando la malafede è evidnetissima

la Bibbia del nuovo Alfista: Per il futuro dell'Alfa Romeo è meglio un pianale più economico che poi tanto l'elettronica e le gommature esagerate risolvono i problemi

www.alfaromeo75.it - http://web.tiscali.it/alfetta.gt.gtv - www.arocalfissima.com/vodcast

Link al commento
Condividi su altri Social

è anche vero che purtroppo siamo in pochi qui dentro a far voce contraria, a metter le pulci e dire qualcosa di diverso, anche perchè poi alla fine uniformarsi al pensiero generale porta a vedere in modo distorto la realtà, o magari uscrire con frasi del tipo "stampa venduta" o ancora "quel giornale non ha mai provato quel modello..."

alla fine stanca in effetti dire la propria in un ambiente che non accetta la diversita di opinioni...

la Bibbia del nuovo Alfista: Per il futuro dell'Alfa Romeo è meglio un pianale più economico che poi tanto l'elettronica e le gommature esagerate risolvono i problemi

www.alfaromeo75.it - http://web.tiscali.it/alfetta.gt.gtv - www.arocalfissima.com/vodcast

Link al commento
Condividi su altri Social

  • 2 settimane fa...
  • 4 settimane fa...

SPORTIVA EVOLUTA

The lightening of an automotive vehicle structure, whether it is an engine support, or a complete car body, demands a specific planning so that the mechanical characteristics of the material being used can be exploited to the maximum.

It is therefore necessary in the first place to ask oneself what the structural mission is of the member in question, so that the general proportions can be determined. As such, the first large task is to ensure that the rigidity requirements are satisfied. For example, if a car body is being developed, one of the most important tasks is to ensure that the windscreen mounts are strong enough. Structural members also have to take full advantage of resistance, in the same way as crumple zones do.

A simple geometrical shape (e.g slab, solid beam) has to be derived, which can be used to assimilate the member under study, with the aim being to partially determine by means of analytical processes the state of stress or rigidity. At this point simple functions can be derived for different load situations, that depend on the mechanical characteristics of the material (modulus of elasticity, density, yield value, breaking resistance).

Moreover, the same method can be applied not only in terms of investigating the weight, where the prevailing parameter can be the rigidity or the specific strength, but also towards minimal cost (employing parameters like “density per Euro”).

A comparison between the various materials for each case of basic geometrical shape can then be drawn up (e.g. a slab stressed by bending). As a material of reference, TRIP 800 is chosen, which is a high performance Steel.

For collisions members, such as cross sections, Titanium alloy represents a 60% weight advantage over Steel, and a 30% weight advantage over Aluminium. Sportiva Evoluta makes use of this benefit. For high volume car production the use of Titanium is not feasible however, due to the requirement of sustainable costs.

After detailed structural analyses were conducted for vehicle rigidity, it was decided to use a composite carbon fibre material for the main member.To obtain suitable deformation in impacts, the front and rear crumple zones have been made out of aluminium and titanium. The main module of the so called “Split Frame” chassis design is fixed with a set of elastic mounts, ensuring a desirable compromise between comfort and handling.

Two processes have been used in the manufacturing of the prototype chassis, which ensure a strong design capable of resisting the high forces imposed during high speed handling and crashes; “hand lay-up” manual lamination, and “RTM” resin transfer moulding.The main chassis is split into two parts, the bulkhead and backbone, which are connected by two rows of bolts.

Manual lamination was used for the backbone member,using a sandwich type structure to increase the strength whilst remaining light in weight. This solution consists of two carbon-fibre sheets, between which an ultra low-density honeycomb panel is inserted to improve rigidity characteristics.

The carbon-fibre sheets themselves consist of many layers of overlapping pre-impregnated woven carbon fibres. To optimize torsional rigidity, and to absorb forces transferred from the suspension, the main backbone tunnel has closed sections.

There are two disadvantages of the manual lamination process, the main one being the fact that it would only be possible to produce one to two cars a day. Although the initial investment for the process is very low, the high labour hours, and more specifically the need for skilled labour elevate the variable costs.

The complex shape of the bulkhead section triggered the engineers at the CRF to explore the potentials of the RTM process. The RTM process uses a stamp, into which a glass-fibre mould is initially inserted.A resin matrix containing carbon fibres is subsequently pumped in under a controlled pressure and temperature. To increase the structural characteristics of the member, a reinforcing material called Nomex was also used.

An economic analysis of the RTM process was also carried out during the project, and demonstrated that the high convenience of the technology would allow for a production figure of between 5 to 10 cars a day.

Advantages and possibilities:

-Weight control: The complete chassis (excluding the suspension) weighs less than 100 Kg.

-Chassis performace adapted for super-sports car: The torsional and flexible rigidity assures compliance with the Euro-NCAP standard (offset collision at 64 km/h with deformable barrier).

-Technologies adapted for production volumes of upto 5 cars a day: The labour intensive process of manual carbon fibre lamination has been eliminated by a new process called VRTM (Vacuum Resin Moulding Transfers).

-This concept represents the first application of VRTM where woven carbonfibre is used for certain high strengh chassis members."

The chassis makes use of split frame architecture technology, allowing for different 'upper bodies' to be mounted on the basic 'lower chassis', by means of elastic mounts which provide the necessary comfort by filtering road and engine noise.

Extensive testing revealed a substantial reduction in noise, vibration and harshness, with audible road and engine noise decreasing by 4-6 dBA (over a regular chassis). Not only can different body styles be used on the same chassis,but the chassis itself can also be easily adapted for different wheelbases, engines, and traction schemes (2WD, 4WD).

Source-italiaspeed

Link al commento
Condividi su altri Social

Crea un account o accedi per lasciare un commento

Devi essere iscritto per commentare e visualizzare le sezioni protette!

Crea un account

Iscriviti nella nostra community. È facile!

Registra un nuovo account

Accedi

Sei già registrato? Accedi qui.

Accedi Ora

×
×
  • Crea Nuovo...

 

Stiamo sperimentando dei banner pubblicitari a minima invasività: fai una prova e poi facci sapere come va!

Per accedere al forum, disabilita l'AdBlock per questo sito e poi clicca su accetta: ci sarai di grande aiuto! Grazie!

Se non sai come si fa, puoi pensarci più avanti, cliccando su "ci penso" per continuare temporaneamente a navigare. Periodicamente ricomparità questo avviso come promemoria.