Thu, 2 Sep 2010|
Dave Dalrymple takes a look at some cutting techniques for vehicle extrication, including cuts used to weaken the vehicle structure. Sponsored by Holmatro.
[MUSIC] Now that we've stabilized the vehicle, we've assessed the scene. There's no hazards, we've taken the glass out. We have our patients protected. Now we have to think about what kind of pathway we need to develop to get our patients disentangled and out of the vehicle onto the street. Now, one of the things to think about with this methodology wise today. We need to strategically cut a vehicle sometimes to help weaken the vehicle structure. Now, part of that process is a two evolution called a fender hinge or fender lift. We're going to actually severe the front crumple zone of the vehicle. Ok, to facilitate a fender evolution what we want to do. Is we wanna reach in and find that front suspension. The reason why we do that, we don't want to cut through the strut or the spring. That would be bad. Alright. The first cut, we're gonna make it vertically in line with that. Suspension. [SOUND] Once we've done that, we're gonna come in and we're gonna cut the bottom of the A post where the fender meets. Meets with the rocker panel, now we just want to the fender though, that's important, we don't want to cut too deep, we just want to sever the fender. One of the things to remember, just like any kind of extraction evolution, they don't go always as planned. A good example was this. This has got an inner fender well made out of steel which is fairly rare today, but you might find it on certain vehicles, especially high-end vehicles. With an inner fender well, that simple fender lift where you're gonna cut in line with the suspension and cut at the bottom of the A-post and fold it up isn't gonna work. You're gonna need to facilitate a simultaneous operation between cutting and spreading to move that fender away from the inner fender well. And work, work your operation that way. [NOISE] This way it'll expose our crumple zone. But you'll notice it will also expose the hinges of the door, too, which allows us to look at taking the door off right off the bat, as well. [NOISE] Now, we're ready to go. To sever our crumple zone. Basically our crumple zone is this hole area right here. The reason why, and each crumple zone will look a little different. Some might be a hole. Some might be a corrugation. Some might be dimpled into the metal. Basically that's an engineered location in that vehicle. That wants to absorb energy in a crash and that will crumple itself and absorb the energy to keep it away from the occupant. The reason why we're making that vertical cut into the crumple zone is to isolate the dash from the rest of the vehicle when we go back and move the dash whether we're gonna lift the dash or we're gonna roll the dash. That vertical cut will allow that dash to move independently of the rest of the vehicle. It also weakens the vehicle structure in that operation too. That facilitates a whole myriad of things. One, it releases some of the energy in the vehicle structure itself. But, by helping it, the structure being weakened, it will help your tool work. Down the road.