re: Under-Run Bars on Trucks : Why they are important for you! Good article and it has come out very well with good illustrations.
Additionally there is something called FUPD - Front Under run Protecting Device. This is mandated by CMVR through AIS 069. In simple terms they are fitted below the front bumpers and should be in a height not more than 500mm from ground. Quote:
Originally Posted by the_skyliner ...
Under-run bars have opposition from truck drivers because sometimes it creates Ground Clearance (GC) issues, especially in case of tippers which carry sand/coal/etc and have to travel to river beds or rock/coal mines. Here a fold-able under-run bar could be a solution. | Quote:
Originally Posted by Rehaan |
They don't have any GC issues, as in many cases the diff case will be lower most. The problem with them is, reduced angle of departure. Also they are mandated only for on road vehicles. Off road vehicles like tippers, dumpers are excluded. But now for Tippers also, they are specifically asked to qualify it as a surface and mining. Quote:
Originally Posted by the_skyliner ...
For regular truck drivers, they see it as an additional cost to save someone else life. Manufacturers should put these bars right at factory then. That could help somewhat...... | Quote:
Originally Posted by W.A.G.7 Nice informative article. Are these under run bars provided by the manufacturer itself, when the truck rolls out of the assembly line? Or are these welded later on by the truck owners to comply with the RTO guidelines? | Quote:
Originally Posted by Rehaan I've been told that as per the rules, all three types (Front / Side & Rear Under-run protecting devices) are now being provided on trucks (ICV and above).
^ Not sure if all manufacturers follow this, or what the enforcement of this is like. Will let some of the Commercial Vehicle experts answer this one! | Quote:
Originally Posted by Rehaan ...After that, for the next steps, I'm not sure. Hopefully we will have a better idea once people chip in regarding what the current regulations are, are they retro-active, are the truck manufacturers responsible or the owners?... |
These are mandated by Central Motor Vehicles Rules (CMVR) and Front, Side & Read (FUPD, SUPD & RUPD) are fitted in the factory. No truck can pass CMVR regulations / sold without them. What's happening is, when they are hit and broken they are not replaced. RUPD gets hit most of the time and they are not replaced/rather insisted by officials. Officials should take strict actions when they find trucks without them. Quote:
Originally Posted by Rehaan ...
I'm no expert, but it does look to me like that under-run bar was a bit high - since the Punto has submarined + the Punto bumper doesn't seem damaged + the bonnet has been scraped up.
If i had to guess, i'd say the presence of that under-run bar (regardless of how poorly/well it was constructed) definitely helped, but overall it mustn't have been a very fast impact. | Quote:
Originally Posted by Rehaan PROBLEM 1: Under-ride bars are mounted too high, leading to the wedge effect. ..So to prevent the wedge effect, the under-run bars need to be mounted at a typical car-bumper height: "Rear underride guards must be placed at a maximum height of 400 mm from the ground on an unloaded truck in order to be effective in avoiding underride of light passenger vehicles." - Source
If this maximum height is not adhered to, the rear guard becomes virtually useless. |
CMVR says, we can have upto 60% of Wheelbase (WB) as Rear Over-Hang (ROH). So unlike passenger cars, trucks have larger ROH and hence is the lower departure angle. And again there is min departure angle which needs to be complied. So RUPD's are placed in the exact location which will barely meet the requirements. That doesn't mean that they are just fitted, but are actually collision tested and certified. Also to make things worse, angle of departure is measured for a laden truck and RUPD is for an unladen truck. Quote:
Originally Posted by Rehaan PROBLEM 2: A lot of under-ride bars are not constructed well enough. This causes them to collapse when they are hit hard, or just on one side. This results in the car traveling under the truck. In the USA, even though under-run protection is required by law, the laws aren't strict enough. A recent study of several trucks showed that only 1 of them did satisfactorily well on an off-set collision test. Keep in mind these test were run at 35 mph (only 56 km/h): |
Basically RUPD's are kind of crumble bars and are designed to absorb the collision rather than resist it like FUPD. That's the reason, RUPD's looks flimsy with just a round bar as against FUPD which looks very robust. Also FUPD's tends to last longer than RUPD's and will survive minor collisions / accidents. Quote:
Originally Posted by Rehaan PROBLEM 3: Under-ride protection isn't present on all trucks in India. If you rear-end a truck, even at a fairly slow speed, the lack of under-ride protection could mean extremely serious injury to your upper body and head, regardless of how safe your car is. |
That's because there is no clause that older trucks needs to have this. So there are chances that they were produced and sold without RUPD and continue to run.
Last edited by Rehaan : 17th December 2013 at 11:03.
Reason: Expanding "WB" and "ROH" to full forms so everyone can figure out what you're saying. Thanks for the info!
|