Advanced steel and new vehicle rescue evolutions


CarolinaFireJournal - Ron Moore
Ron Moore
01/11/2010 -

Rescuers across this country are becoming increasingly aware that automakers are integrating new, tougher and stronger steel into their newest model vehicles so they can meet new government crash standards. The industry term ‘Boron’ is becoming more and more familiar to vehicle rescue personnel as well as our rescue tool vendors. Boron is just one of the various types of a new alloy steel family that are called ‘advanced steels.’ Boron, Martensite, Dual Phase, and TRIP steel are all examples of this new generation of steel that is challenging rescue personnel. It is 25 percent lighter in weight and eight times stronger than the steel we are currently used to in vehicles.

image

BThis cross-section of a B-pillar from a Chrysler vehicle shows the outer layers of high-strength steel. The Cshaped inner layer is hot-stamped Boron steel and is what will resist your cutting efforts.

Over the past several years, advanced steels have been integrated into structural areas of vehicles as all US automakers begin phasing in compliance with the two tougher government crash standards that become official with the 2012 model year. One requires a tougher, more crashworthy side of the vehicle. The other requires a stronger roof. Together, these standards will result in a better and safer vehicle for those occupants during a collision. We have already seen this result over the past few years when we encounter crashes with advanced steel vehicles involved. Vehicles with Boron structural areas are holding up well in collisions; better than what we would normally expect.

A short ram pushing off the center tunnel may be able to move a crushed B-pillar out and away from your patient.

The problem is that even a vehicle with advanced steel roof pillars, roof rails and rocker area can be involved in a collision that is severe enough that even this new steel bends, folds and crumples. This is when advanced steel will challenge the unprepared rescuer. Without a practically brand new hydraulic power cutter, the rescuer might find that they will be unable to cut through any of the areas where the advanced steel is located. Unless your power cutter is new, or within one or two years old, you might not be able to cut the roof off for example or even lay a B-pillar down after a T-bone collision. Older generation power cutters most likely won’t be able to cut this stuff! Your air chisel bits will all break before the Boron steel will even make a dent. The teeth on your best demolition quality reciprocating saw blade will quickly be worn off without so much as even scratching the advanced steel.

What do you do? Well, one solution, now that you know you have a problem, is to buy a new model power cutter from a manufacturer that you can be assured has designed the tool to cut through these new advanced steels. The blades will probably be thicker than your old cutter and the body of the tool may even be bigger. One manufacturer has even designed an addition to their simo-pump to increase the fluid flow to the tool. To be successful, it’s almost like the cutter blades have to just slam through this stuff without hesitation. The metal in a roof pillar made of advanced steel actually cuts only partially. As the blades of an advanced steel-capable cutter close, the bulk of the advanced steel will actually fracture. You might even hear a sound similar to breaking glass and see a significant pop action when the cut is completed.

What’s confusing about advanced steel is where it is located. In the design of a roof pillar as an example, the entire pillar is not made of advanced steel; just an inner layer of steel. The rest of the pillar and everything you can see as you look at it at a crash scene is just plain steel. The tough stuff is always a layer hidden inside the hollow of the pillar or roof rail.

If you did not have the capability of cutting through a B-pillar constructed with advanced steels, a pie cut into the roof rail may be sufficient enough to allow you to pull the top of the B-pillar free.

So until you and the department can figure out how you’ re going to afford to meet the challenge of purchasing a new power cutter and possibly even a better, higher flow power plant, what do you do? The solution might be in expanding your list of skills that you and your rescue team can perform. In other words, instead of hopelessly trying to cut through steel that is tougher than any cutting tool you have in your rescue inventory, let’s look at working around it.

The following is an overview of options you might employ at a crash scene when advanced steel essentially has you shut down. Some of these evolutions are old ones; some are new. The point is that you need options when you encounter an advanced steel extrication. Whether your solution to freeing your trapped patient is through a good old reliable technique that you might not have thought about for years, or a brand new one that you’ ve just been made aware of, the patient doesn’t care. They just want out. Let’s look at some advanced steel rescue evolutions that should be in your mental ‘toolbox’ as you roll up to the scene.

Ram the Pillars

A longer ram as shown here may be able to push against both B-pillars and spread the width of the vehicle back to normal so you can free your trapped patient.

Typically, when a vehicle is struck broadside and the B-pillar crushes in on the occupant, we generally open and remove a door and probably cut the B-pillar near the roof line and lay the B-pillar down out of the way. Well, with advanced steel, you might not be able to cut that pillar. So, what do you do? If you can’t cut it; move it. Remember that if the pillar crushed in on your patient then why don’t you consider just pushing it back towards its normal position. A short ram off the center floorboard tunnel might just move the pillar outward enough to get your patient free. A longer ram with a good spread might just be the ticket to actually widening the vehicle from pillar to pillar.

Pie Cut

In another scenario, let’s say that you can’t cut through the B-pillar. As you attempt to cut it, the blades of your power tool just stall out without making any cuts. The best advice is to keep probing around with your cutter. Maybe it is only the B-pillar itself that is Boron. Maybe the roof rails are just high-strength steel; something that you can cut.  The good old ‘pie cut’ evolution, where you make cuts into the roof rail in front of and just behind the B-pillar might allow you to get the B-pillar free enough to move it out of the way if you find that the roof rail is ‘soft.’

Lift the Pillar Up

It is also possible that the manufacturer designed the roof rail and most of the B-pillar to have advanced steel inside but the very bottom of the pillar and all of the rocker might again be high strength or even mild steel. So do you see the plan? If I can’t cut the top of the B-pillar and lay it down, why don’t I cut the bottom of the B-pillar and lift it up? Yes, that might just be a good option; especially if you encounter a Dodge, Chrysler or Jeep vehicle with advanced steel. This is exactly how their B-pillar is designed; Boron from top to just below the bottom door hinge. The very bottom of the pillar and the entire rocker are regular steel.

In this simulation, the rescue team doesn’t have a cutter on scene that is capable of cutting the Boron B-pillar. By cutting the pillar at the rocker, the team found high-strength steel but not Boron. This low cut will allow the pillar to be lifted up instead of bent down.

Ram the Roof Off

In this scenario, you encounter a new model advanced steel structure vehicle with all of the roof rail, all of the B-pillar and all of the rocker having Boron or Martensite steel inside. What now? Well, think about taking a ram and ramming the roof off. With cribbing beneath the rocker to support the tool, a power ram might be able to actually tear the spot welds where the B-pillar joins the roof rail, freeing the post so it can be bent down and away from your patient.

Total Sunroof Evolution

If you run into an advanced steel vehicle that has the entire side structure made of tough, advanced steels, you might want to consider going vertical; total sunroof evolution. To accomplish this, you take a cutting tool such as a reciprocating saw and cut through the roof from the front windshield header all the way to the rear window. You cut along a line about six to eight inches in from the side edge of the roof itself. Once completely cut from front to back, rescuers can lift the roof panel up, completely opening the roof area above your patient. If the patient cannot come out vertically at this time, then put a spreader or ram tool inside the car and widen the body of the vehicle by pushing on the B-pillars. You can almost lay the vehicle’s sides out completely flat with enough effort and a long ram.

When there is no tool available to cut an advanced steel pillar or roof rail. An option might be to ram the roof off. A power ram, placed on the rocker with cribbing beneath, may be powerful enough to tear the spot welds and free the pillar at the roof line.

The challenge is out there. It’s up to you to work on getting a new cutter and maybe even a power plant that is proven to go through the advanced steels. Then secondly, you need to train on these advanced steel evolutions so you have plenty of choices if your patient is trapped in a late-model vehicle that is built with advanced steel.

 

Once the pillar tears off the roof in front of and behind the pillar, it may be possible to lay the pillar down or at least bend it down and away from the trapped patient.

 

 

For the total sunroof evolution, a recip saw is used to cut the roof panel from the windshield header to the back window.

 

 

With the long cut completed and smaller ‘hinge’ cuts on the opposite side, the crew can lift the entire roof panel up and away from the patient area.

 

 

In this scenario, the entire roof rail and all pillars were advanced steel and the crew did not have any capable cutting tools. The total sunroof  assignment makes a large opening and allows the sides to be widened if additional space is still needed to free the patients.

 

 

 

Ron Moore is the Training Officer for the McKinney (TX) Fire Department. He also writes the University of Extrication series published in Firehouse Magazine and is forum moderator for the University of Extrication Message Forum on the www.firehouse.com website. Moore can be contacted for further information on his advanced steel research project or to answer questions you may have on this topic. E-mail him at [email protected]
Comments & Ratings
rating
  Comments


Issue 32.4 | Fall 2018

Past Issue Archives