Board logo

roll-bar; arness anchorages
xico_ze54 - 2/2/07 at 09:18 PM

can you please take a look at this sketch and say your opinion if this kind of roll-bar/arness anchorages would pass in a SVA test? Rescued attachment roll-bar.jpg
Rescued attachment roll-bar.jpg


Guinness - 2/2/07 at 09:36 PM

I'm no expert, but I don't think it would pass like that

Imagine being in a head on accident, you and your passenger will still be moving forward, stopped only by the seat belts.

Both seat belts are mounted to the cross rail of the roll bar. That means that bar has to hold approx 3000kgs?

(Assuming each passenger is 75kg and the SVA manual wants to see a 20G loading?) See here for recent thread.

http://www.locostbuilders.co.uk/viewthread.php?tid=59030

It would have to be pretty thick and securely welded to the vertical hoop to cope with that sort of shock load.

Far better to introduce some triangulation into it (IMHO).

Mike


ProjectX - 2/2/07 at 09:43 PM

Not sure about the bolts to the chassis and Mike you beat me to it!

quote:

I'm no expert, but I don't think it would pass like that



This might help with the seatbelt anchorages



HTH

Jamie


scutter - 3/2/07 at 10:29 AM

Your half way there, the rear braces need to be stronger, why not take them down the rear corners of the chassis. Mine passed SVA like this.


getting worse
getting worse


ATB Dan.


xico_ze54 - 3/2/07 at 12:42 PM

thanks for the advices.

but... How about those cases of chromated rol-bars (I was thinking in chromated mine)? they have to be bolted on chassis, not welded. Or is that the case of SVA no longer accept bolted roll-bars?

another thing: I also made those calculations in case of colision, but aren't you forger that weights have to be divided by 2, due to lower anchorages?

one more thing: my main tubes are Ø45mm/2,5mm wall, and intend for the rears Ø25mm/2mm wall.

[Edited on 3/2/07 by xico_ze54]

[Edited on 3/2/07 by xico_ze54]