I was recently observing an extrication class where the group was being shown ways to stabilize a roof-resting vehicle. The salesman/instructor showed the class how to use two struts along with chain and a chain cluster to secure the rear of the vehicle.
When I do this, I run a loop of chain around the end of the vehicle and then have the struts sort of lift the loop of chain to stabilize the vehicle. Well, not this time. The salesman/instructor showed the class that they should take a chain cluster kit and use the chain 'T' attachment end. He inserted the 'T' into the hole in the frame of the vehicle and then lifted with the struts to tighten and stabilize the vehicle. Or did he?
I have never seen anyone use those frame holes for essentially lifting a vehicle. They are designed for securing a new vehicle onto a car carrier when it is being transported to the new car dealership.
What I saw with this technique was that the metal at this hole in the frame bent and actually began to show failure. If the metal at this frame opening opens up and releases the chain cluster, then the strut would fail.
I do not agree with this technique and feel it should be shutdown right here and now. A loop of chain or a complete securing of the chain to the vehicle frame will be far superior to using the frame hole in this fashion.
Here's a shot of one of the struts on one side of the roof-resting vehicle to better explain what I'm talking about. It's NOT safe. It's NOT secure. It should NOT be a technique that we use or teach!
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11-11-2012, 05:49 PM #1
Unsafe New Stabilization Technique
Last edited by rmoore; 11-11-2012 at 05:57 PM.
11-11-2012, 05:52 PM #2
A close-up view of the chain cluster with the 'T' head inserted into the hole in the vehicle's frame. Normally, a loop of chain is run under the trunk area and two struts lift that loop of chain to tighten. Not here. The strut is only secured to that hole in the frame...
11-11-2012, 05:55 PM #3
Close-up view of the chain cluster "T" head showing how it is already causing the metal of the frame around the hole to distort. If that one layer of metal fails, the chain detaches and the strut disconnects.
This is unsafe, I think. What's your take on this?
11-11-2012, 06:05 PM #4
I would consider using that attachment point to stabilize but it definitely wouldn't be my first choice to lift."Nemo Plus Voluptatis Quam Nos Habant"
The Code is more what you'd call "guidelines" than actual rules.
11-12-2012, 09:22 PM #5
- Join Date
- Apr 2006
Grade 80 chain is a minimum for overhead lifting. I have not taken this class and I was not there so I am just going by the picture that does not look like grad 80 chain. I do not believe a grade 80 chain cluster exists so this seems like a salesman trying to show off, no real useful value.
11-13-2012, 01:37 PM #6
It's been awhile! I haven't been here lately but thought I'd throw a couple of comments at this one.
You have a few issues here:
1) Some "T-Hook" holes would hold this load without any problem, and some are on cheap cars that have paper thin frames. I believe the hook itself has a 5,400 Lb. working load. Like pretty much everything we do there is no universal answer. However, running the chain under the car and grabbing it with two struts while making sure the chain can't slip out has (so far) worked every time for me, and I started using that technique around 1995.
2) This strut is side loaded. It is in contact with the side of the car with the chain pulling out of the head at an angle. Every strut manufacturer will tell you not to do this.
3) Chain... We are not performing "Overhead Lifting". That is an OSHA regulated field (similar to Confined Space rescue) which does not apply to the Fire Service except in rare situations where a FEMA or rescue team is working with civilian cranes during collapse or trench rescue. The reason there are no Grade 80 hook clusters is that the chain manufacturers do not approve of the use of Grade 80 chain around crashed cars since any exposure to battery acid requires a Grade 80 chain to be removed from service (hydrogen embrittlement). They are all Grade 43/70.
11-13-2012, 02:43 PM #7
Thanks for the input. Not only do I object to using the hole in the frame, you beat me to my next point. In order to 'lift' with the technique shown, the strut has to be extended far above the vehicle. This automatically creates the side loading condition; something that should be avoided.
So, two good reasons why the technique shown is not a safe one or an effective one; frame hole failure and strut side loading.
I'm with Tim. I'll wrap a loop of chain and do it the way I know is safe and gets the job done.
11-15-2012, 10:48 PM #8
- Join Date
- Apr 2006
If its being lifted something has to be under it right? CYA because I'm sure OSHA will have a lot to say when things do go bad!
11-16-2012, 12:02 AM #9
- Join Date
- Nov 2002
Heh, heh, I thought this was going to be about that rediculous "stabilization" they did on "Chicago Fire" the other week. (just watched that one episode to see how bad it was)
11-18-2012, 08:57 PM #10
Not agreeing with the technique shown, but let me play devil's advocate a bit...
They are not lifting with this set up. If they were to lift I am sure that a crib stack would be built in place to crib/lift an inch. Then if the T-hole fails, the load is caught.
The need to stabilize is only to remove a patient from the situation. We are not looking for a long term fix to a vehicle upside down. Is this method shown so a trunk tunnel still can be performed with the chain cradle (perfered method) being completely out of the way?
Don't think I would add this T-hole method to the play book, but if we are only looking to stabilize a car there shouldn't be that much weight placed on these attachment points to deform them. If the instructor/salesman was lifting with this method, he probably should be enlightend to your thinking.~Drew
USAR TF Rescue Specialist
12-17-2012, 11:18 AM #11
- Join Date
- May 2000
- SW MO
01-04-2013, 05:07 PM #12
- Join Date
- Jan 2013
Hey everybody, we don’t post often and had some trouble even getting our old account on here to work, so this is our first post under this username. So.. Hello! Most anything that we post from this account will be approved by a member of our engineering department at Res-Q-Jack.
As you all have pointed out, there are 2 questionable things going on in these pictures: 1. Hanging the vehicle by its tow points. 2. Side loading the struts.
For the 1st issue… We agree with Ron and Tim that this is not an ideal location to lift the car from and other means like a chain wrap would be a better solution in this scenario. However, the safety of this operation would be mostly dictated by the quality/condition of the tow points and, of course, the proper use of cribbing. Certainly some tow points are up to the task and others are not close.
On the 2nd issue. Res-Q-Jack does NOT recommend side-loading any strut as shown in the picture. In fact, in lifts where side loading may easily occur, we recommend starting out with a hand-width space between the strut and the object. Ron, you correctly pointed out that use of the high lifting point is the CAUSE of the side loading in this setup. This would be considered a beam load. The strut is not rated under that condition and it will certainly fail under less load than when being used correctly as a column.
You can see the procedure for spacing the strut out a hand-width in a couple of the scenarios in our quick reference guide:
If you have been told otherwise by a Res-Q-Jack representative, please contact our office and let us know who is recommending such loading so we may correct them.
Thanks to all of you guys who study this stuff and keep progressing the safety and skills in this field!
01-05-2013, 02:56 AM #13
- Join Date
- Feb 2008
Just to shed some light from the towing industry into the situation being presented. Now before everyone jumps on it I completely understand that this is not a towing situation however if they don't do it it makes you wonder why atleast. First the frame holes in question are not rated by the manufacturing there is no standard and everyone will be different. Second the T-Hook use the reason you are seeing the stress in the photos is because it is improper use of the T-Hook. The hook needs to be at a 90 degree angle to the frame if you catch what im saying. Without being able to illustrate it the flat side on the last picture should be riding along the frame if that condition is not met a shift in load will could cause the T-hook to twist and become unsecured. The most secure and simplest way would be to go around the axle and frame.
01-27-2013, 07:29 PM #14
Ron,another potential hook point would be to wrap a chain around the frame just ahead of the rear bumper shock stantion. Might not be possible on the car with the bumper attached but this one doesn't have one. I'd PREFER to undersling the rear deck area with a rated chain or strap.
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