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Load crashes off truck going downhill.
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Previously:
https://www.homemadetools.net/forum/...6158#post83176
https://www.homemadetools.net/forum/...434#post110539
The first thing I noticed as coon as the vid started was they didn't have the load properly secured. Not a single chain from the widest parts of the load to the trailer.
Those GoldHofer style modular platform trailers are horrible to try and chain to because they done have good places to attach a chain along the lower parts of the outside rails.
The chains they had on the load were running at the wrong angles you always want to have chains pulling down from the widest points possible and straight across from each other running them diagonal to each other is fine but not in 2 planes at the same time. the hauling company needs to stick to hauling square boxes if they can't secure a load any better than that.
Another thing is why were there no apparent brakes on the trailer the truck wheels could be seen sliding due to braking but the trailer should have been doing the majority of the braking.
The real problem was they had more weight on the trailer than the two trucks could stop going down the hill. Should have had much heavier and larger fore and aft trucks capable of stopping the loaded trailer, especially at the aft end.
First thing I noticed was they were going way to fast!
Jon, Looks like the Three Gorges Dam on the Yangtze River in China. HUGE project, HUGE dam! Was just there for a tour and a lift down on their 'ship lift' vertical elevator. As Frank says, these guys don't understand basic tie down or braking requirements for such a load...I'll bet they did not help in the dam build! Cheers
Jim
It looks to me as if the drag tractor got off line in the first few seconds of the video. It appears the front end splays off toward the camera just as it is cresting the rise.
This isn't too surprising at all. I lived in China for 5.5 years, and it was pretty common to see heavy equipment on a flatbed truck with no chains, and rolling good speed down the highway. If the flatbed was empty, they'd just throw whatever wood blocking on loose, and for the most part it'd stay on.
In this video, it also looks like there's a truck/trailer right at the bottom of the hill, which is probably why the lead truck slammed on his brakes to stop. Once those brakes locked, and the wheels started to skid, it was all over. Sliding friction is much lower than rolling friction, so once it started sliding, it was able to keep moving.
As Frank mentioned, lack of tie downs, too much weight on the trailer vs the trucks.
Another thing I noticed about the trucks and trailers in general in China was that their condition is usually quite poor. They run them very hard, extremely overloaded with poor tires. Most of the lights don't work, shields and guards are gone or baling wire to hold them on, poor welds on any repairs.... so its quite possible that the brakes on that trailer just don't work.
Preventative maintenance on trucks is just not part of their thinking. I can't count the number of times I saw a heavy truck on the side of the road with the driveshaft end on the ground because the u-joint in the driveshaft blew. Rather than fixing it before it blew apart, they'd wait until it broke completely, then a small white repair van would show up, and fix it on the side of a busy highway.
I've also seen an engine being overhauled on the side of the highway, and transmissions as well.
We'd always be driving on vendor visits to manufacturing places, so I'd see a lot of highway time. Unfortunately I wouldn't always be able to get my camera ready in time.
I made several trips to China as well. mostly to trade fairs then to inspect the factories where the items we were thinking of ordering. W always found it best to hire our transportation through the hotels where we were staying or take their excellent metro system.
And Yes just as Kent described there are some poorly maintained vehicles especially in the more remote areas. Around the larger cities not quite as bad.
I would say someone forgot to hook up the trailer brakes. :sweating:
The driver should have used the trailer brake only. The sliding rear end of the tractor turned the congear towards the edge of the road. Trucks are equipped with a hand valve in the cab for trailer brake only. Been a truck driver for 40 years retired now.
The lead truck was turning to the right the load kept going straight because of no properly tied down and no brakes on the trailer.
Ralph
Right Ralph. I figured someone forgot to hook up the air line. How dumb. Also, the operator may have panicked and locked up the tractor brakes thus unable to steer out of it since the front wheels weren't turning. I've seen that happen hundreds of time on the race track by new drivers. You can usually steer out of a skid if you can be gentle with the brake peddle. Not to say that I wouldn't have panicked too.
I'm no expert but they ,in my opinion needed much more power and weight at the rear so the rear ones can hold back the load as we used to do when towing vehicles with cables or chains. The brakes on the trailer/lowloader looked to me as they were working but the load was pushing the tow vehicle as in a jack-knife.
Good thing that white post barrier was in place... it prevented the load from going over the edge. :rimshot:
I looked at the video full screen and it looks to me like all the wheels on the trailer were locked up also which would mean that the road surface needed to be blacktop or concrete to provide much greater grip for the tyres. A driver who understood braking may have been able to save this by using less braking as locked up wheels have far less grip than slowly rotating tyres - and that is the whole reason for anti-skid brakingQuote:
Originally Posted by Frank S